unicorn/qemu/target/i386/fpu_helper.c

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2015-08-21 07:04:50 +00:00
/*
* x86 FPU, MMX/3DNow!/SSE/SSE2/SSE3/SSSE3/SSE4/PNI helpers
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
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#include <math.h>
#include "cpu.h"
#include "exec/helper-proto.h"
#include "qemu/host-utils.h"
#include "exec/exec-all.h"
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#include "exec/cpu_ldst.h"
#include "fpu/softfloat.h"
target/i386: reimplement f2xm1 using floatx80 operations The x87 f2xm1 emulation is currently based around conversion to double. This is inherently unsuitable for a good emulation of any floatx80 operation, even before considering that it is a particularly naive implementation using double (computing with pow and then subtracting 1 rather than attempting a better emulation using expm1). Reimplement using the soft-float operations, including additions and multiplications with higher precision where appropriate to limit accumulation of errors. I considered reusing some of the m68k code for transcendental operations, but the instructions don't generally correspond exactly to x87 operations (for example, m68k has 2^x and e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors from applying multiple such operations each rounding to floatx80 precision, I wrote a direct implementation of 2^x - 1 instead. It would be possible in principle to make the implementation more efficient by doing the intermediate operations directly with significands, signs and exponents and not packing / unpacking floatx80 format for each operation, but that would make it significantly more complicated and it's not clear that's worthwhile; the m68k emulation doesn't try to do that. A test is included with many randomly generated inputs. The assumption of the test is that the result in round-to-nearest mode should always be one of the two closest floating-point numbers to the mathematical value of 2^x - 1; the implementation aims to do somewhat better than that (about 70 correct bits before rounding). I haven't investigated how accurate hardware is. Backports commit eca30647fc078f4d9ed1b455bd67960f99dbeb7a from qemu
2021-02-25 18:22:50 +00:00
#include "fpu/softfloat-macros.h"
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#define FPU_RC_MASK 0xc00
#define FPU_RC_NEAR 0x000
#define FPU_RC_DOWN 0x400
#define FPU_RC_UP 0x800
#define FPU_RC_CHOP 0xc00
#define MAXTAN 9223372036854775808.0
/* the following deal with x86 long double-precision numbers */
#define MAXEXPD 0x7fff
#define EXPBIAS 16383
#define EXPD(fp) (fp.l.upper & 0x7fff)
#define SIGND(fp) ((fp.l.upper) & 0x8000)
#define MANTD(fp) (fp.l.lower)
#define BIASEXPONENT(fp) fp.l.upper = (fp.l.upper & ~(0x7fff)) | EXPBIAS
#define FPUS_IE (1 << 0)
#define FPUS_DE (1 << 1)
#define FPUS_ZE (1 << 2)
#define FPUS_OE (1 << 3)
#define FPUS_UE (1 << 4)
#define FPUS_PE (1 << 5)
#define FPUS_SF (1 << 6)
#define FPUS_SE (1 << 7)
#define FPUS_B (1 << 15)
#define FPUC_EM 0x3f
#define floatx80_lg2 make_floatx80(0x3ffd, 0x9a209a84fbcff799LL)
#define floatx80_lg2_d make_floatx80(0x3ffd, 0x9a209a84fbcff798LL)
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#define floatx80_l2e make_floatx80(0x3fff, 0xb8aa3b295c17f0bcLL)
#define floatx80_l2e_d make_floatx80(0x3fff, 0xb8aa3b295c17f0bbLL)
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#define floatx80_l2t make_floatx80(0x4000, 0xd49a784bcd1b8afeLL)
#define floatx80_l2t_u make_floatx80(0x4000, 0xd49a784bcd1b8affLL)
#define floatx80_ln2_d make_floatx80(0x3ffe, 0xb17217f7d1cf79abLL)
#define floatx80_pi_d make_floatx80(0x4000, 0xc90fdaa22168c234LL)
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static inline void fpush(CPUX86State *env)
{
env->fpstt = (env->fpstt - 1) & 7;
env->fptags[env->fpstt] = 0; /* validate stack entry */
}
static inline void fpop(CPUX86State *env)
{
env->fptags[env->fpstt] = 1; /* invalidate stack entry */
env->fpstt = (env->fpstt + 1) & 7;
}
static inline floatx80 helper_fldt(CPUX86State *env, target_ulong ptr,
uintptr_t retaddr)
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{
CPU_LDoubleU temp;
temp.l.lower = cpu_ldq_data_ra(env, ptr, retaddr);
temp.l.upper = cpu_lduw_data_ra(env, ptr + 8, retaddr);
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return temp.d;
}
static inline void helper_fstt(CPUX86State *env, floatx80 f, target_ulong ptr,
uintptr_t retaddr)
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{
CPU_LDoubleU temp;
temp.d = f;
cpu_stq_data_ra(env, ptr, temp.l.lower, retaddr);
cpu_stw_data_ra(env, ptr + 8, temp.l.upper, retaddr);
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}
/* x87 FPU helpers */
static inline double floatx80_to_double(CPUX86State *env, floatx80 a)
{
union {
float64 f64;
double d;
} u;
u.f64 = floatx80_to_float64(a, &env->fp_status);
return u.d;
}
static inline floatx80 double_to_floatx80(CPUX86State *env, double a)
{
union {
float64 f64;
double d;
} u;
u.d = a;
return float64_to_floatx80(u.f64, &env->fp_status);
}
static void fpu_set_exception(CPUX86State *env, int mask)
{
env->fpus |= mask;
if (env->fpus & (~env->fpuc & FPUC_EM)) {
env->fpus |= FPUS_SE | FPUS_B;
}
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
static inline uint8_t save_exception_flags(CPUX86State *env)
{
uint8_t old_flags = get_float_exception_flags(&env->fp_status);
set_float_exception_flags(0, &env->fp_status);
return old_flags;
}
static void merge_exception_flags(CPUX86State *env, uint8_t old_flags)
{
uint8_t new_flags = get_float_exception_flags(&env->fp_status);
float_raise(old_flags, &env->fp_status);
fpu_set_exception(env,
((new_flags & float_flag_invalid ? FPUS_IE : 0) |
(new_flags & float_flag_divbyzero ? FPUS_ZE : 0) |
(new_flags & float_flag_overflow ? FPUS_OE : 0) |
(new_flags & float_flag_underflow ? FPUS_UE : 0) |
(new_flags & float_flag_inexact ? FPUS_PE : 0) |
(new_flags & float_flag_input_denormal ? FPUS_DE : 0)));
}
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static inline floatx80 helper_fdiv(CPUX86State *env, floatx80 a, floatx80 b)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
floatx80 ret = floatx80_div(a, b, &env->fp_status);
merge_exception_flags(env, old_flags);
return ret;
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}
static void fpu_raise_exception(CPUX86State *env, uintptr_t retaddr)
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{
if (env->cr[0] & CR0_NE_MASK) {
raise_exception_ra(env, EXCP10_COPR, retaddr);
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}
#if !defined(CONFIG_USER_ONLY)
else {
cpu_set_ferr(env);
}
#endif
}
void helper_flds_FT0(CPUX86State *env, uint32_t val)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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union {
float32 f;
uint32_t i;
} u;
u.i = val;
FT0 = float32_to_floatx80(u.f, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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merge_exception_flags(env, old_flags);
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}
void helper_fldl_FT0(CPUX86State *env, uint64_t val)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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union {
float64 f;
uint64_t i;
} u;
u.i = val;
FT0 = float64_to_floatx80(u.f, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fildl_FT0(CPUX86State *env, int32_t val)
{
FT0 = int32_to_floatx80(val, &env->fp_status);
}
void helper_flds_ST0(CPUX86State *env, uint32_t val)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int new_fpstt;
union {
float32 f;
uint32_t i;
} u;
new_fpstt = (env->fpstt - 1) & 7;
u.i = val;
env->fpregs[new_fpstt].d = float32_to_floatx80(u.f, &env->fp_status);
env->fpstt = new_fpstt;
env->fptags[new_fpstt] = 0; /* validate stack entry */
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fldl_ST0(CPUX86State *env, uint64_t val)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int new_fpstt;
union {
float64 f;
uint64_t i;
} u;
new_fpstt = (env->fpstt - 1) & 7;
u.i = val;
env->fpregs[new_fpstt].d = float64_to_floatx80(u.f, &env->fp_status);
env->fpstt = new_fpstt;
env->fptags[new_fpstt] = 0; /* validate stack entry */
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fildl_ST0(CPUX86State *env, int32_t val)
{
int new_fpstt;
new_fpstt = (env->fpstt - 1) & 7;
env->fpregs[new_fpstt].d = int32_to_floatx80(val, &env->fp_status);
env->fpstt = new_fpstt;
env->fptags[new_fpstt] = 0; /* validate stack entry */
}
void helper_fildll_ST0(CPUX86State *env, int64_t val)
{
int new_fpstt;
new_fpstt = (env->fpstt - 1) & 7;
env->fpregs[new_fpstt].d = int64_to_floatx80(val, &env->fp_status);
env->fpstt = new_fpstt;
env->fptags[new_fpstt] = 0; /* validate stack entry */
}
uint32_t helper_fsts_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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union {
float32 f;
uint32_t i;
} u;
u.f = floatx80_to_float32(ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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return u.i;
}
uint64_t helper_fstl_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
2015-08-21 07:04:50 +00:00
union {
float64 f;
uint64_t i;
} u;
u.f = floatx80_to_float64(ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
2015-08-21 07:04:50 +00:00
return u.i;
}
int32_t helper_fist_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
2015-08-21 07:04:50 +00:00
int32_t val;
val = floatx80_to_int32(ST0, &env->fp_status);
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if (val != (int16_t)val) {
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
set_float_exception_flags(float_flag_invalid, &env->fp_status);
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val = -32768;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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return val;
}
int32_t helper_fistl_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
target/i386: reimplement f2xm1 using floatx80 operations The x87 f2xm1 emulation is currently based around conversion to double. This is inherently unsuitable for a good emulation of any floatx80 operation, even before considering that it is a particularly naive implementation using double (computing with pow and then subtracting 1 rather than attempting a better emulation using expm1). Reimplement using the soft-float operations, including additions and multiplications with higher precision where appropriate to limit accumulation of errors. I considered reusing some of the m68k code for transcendental operations, but the instructions don't generally correspond exactly to x87 operations (for example, m68k has 2^x and e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors from applying multiple such operations each rounding to floatx80 precision, I wrote a direct implementation of 2^x - 1 instead. It would be possible in principle to make the implementation more efficient by doing the intermediate operations directly with significands, signs and exponents and not packing / unpacking floatx80 format for each operation, but that would make it significantly more complicated and it's not clear that's worthwhile; the m68k emulation doesn't try to do that. A test is included with many randomly generated inputs. The assumption of the test is that the result in round-to-nearest mode should always be one of the two closest floating-point numbers to the mathematical value of 2^x - 1; the implementation aims to do somewhat better than that (about 70 correct bits before rounding). I haven't investigated how accurate hardware is. Backports commit eca30647fc078f4d9ed1b455bd67960f99dbeb7a from qemu
2021-02-25 18:22:50 +00:00
int32_t val;
set_float_exception_flags(0, &env->fp_status);
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val = floatx80_to_int32(ST0, &env->fp_status);
if (get_float_exception_flags(&env->fp_status) & float_flag_invalid) {
val = 0x80000000;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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return val;
}
int64_t helper_fistll_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int64_t val;
val = floatx80_to_int64(ST0, &env->fp_status);
if (get_float_exception_flags(&env->fp_status) & float_flag_invalid) {
val = 0x8000000000000000ULL;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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return val;
}
int32_t helper_fistt_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int32_t val;
val = floatx80_to_int32_round_to_zero(ST0, &env->fp_status);
if (val != (int16_t)val) {
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
set_float_exception_flags(float_flag_invalid, &env->fp_status);
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val = -32768;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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return val;
}
int32_t helper_fisttl_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
int32_t val;
val = floatx80_to_int32_round_to_zero(ST0, &env->fp_status);
if (get_float_exception_flags(&env->fp_status) & float_flag_invalid) {
val = 0x80000000;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
return val;
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}
int64_t helper_fisttll_ST0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
int64_t val;
val = floatx80_to_int64_round_to_zero(ST0, &env->fp_status);
if (get_float_exception_flags(&env->fp_status) & float_flag_invalid) {
val = 0x8000000000000000ULL;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
return val;
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}
void helper_fldt_ST0(CPUX86State *env, target_ulong ptr)
{
int new_fpstt;
new_fpstt = (env->fpstt - 1) & 7;
env->fpregs[new_fpstt].d = helper_fldt(env, ptr, GETPC());
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env->fpstt = new_fpstt;
env->fptags[new_fpstt] = 0; /* validate stack entry */
}
void helper_fstt_ST0(CPUX86State *env, target_ulong ptr)
{
helper_fstt(env, ST0, ptr, GETPC());
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}
void helper_fpush(CPUX86State *env)
{
fpush(env);
}
void helper_fpop(CPUX86State *env)
{
fpop(env);
}
void helper_fdecstp(CPUX86State *env)
{
env->fpstt = (env->fpstt - 1) & 7;
env->fpus &= ~0x4700;
}
void helper_fincstp(CPUX86State *env)
{
env->fpstt = (env->fpstt + 1) & 7;
env->fpus &= ~0x4700;
}
/* FPU move */
void helper_ffree_STN(CPUX86State *env, int st_index)
{
env->fptags[(env->fpstt + st_index) & 7] = 1;
}
void helper_fmov_ST0_FT0(CPUX86State *env)
{
ST0 = FT0;
}
void helper_fmov_FT0_STN(CPUX86State *env, int st_index)
{
FT0 = ST(st_index);
}
void helper_fmov_ST0_STN(CPUX86State *env, int st_index)
{
ST0 = ST(st_index);
}
void helper_fmov_STN_ST0(CPUX86State *env, int st_index)
{
ST(st_index) = ST0;
}
void helper_fxchg_ST0_STN(CPUX86State *env, int st_index)
{
floatx80 tmp;
tmp = ST(st_index);
ST(st_index) = ST0;
ST0 = tmp;
}
/* FPU operations */
static const int fcom_ccval[4] = {0x0100, 0x4000, 0x0000, 0x4500};
void helper_fcom_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
FloatRelation ret;
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ret = floatx80_compare(ST0, FT0, &env->fp_status);
env->fpus = (env->fpus & ~0x4500) | fcom_ccval[ret + 1];
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fucom_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
FloatRelation ret;
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ret = floatx80_compare_quiet(ST0, FT0, &env->fp_status);
env->fpus = (env->fpus & ~0x4500) | fcom_ccval[ret + 1];
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
static const int fcomi_ccval[4] = {CC_C, CC_Z, 0, CC_Z | CC_P | CC_C};
void helper_fcomi_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int eflags;
FloatRelation ret;
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ret = floatx80_compare(ST0, FT0, &env->fp_status);
eflags = cpu_cc_compute_all(env, CC_OP);
eflags = (eflags & ~(CC_Z | CC_P | CC_C)) | fcomi_ccval[ret + 1];
CC_SRC = eflags;
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fucomi_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int eflags;
FloatRelation ret;
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ret = floatx80_compare_quiet(ST0, FT0, &env->fp_status);
eflags = cpu_cc_compute_all(env, CC_OP);
eflags = (eflags & ~(CC_Z | CC_P | CC_C)) | fcomi_ccval[ret + 1];
CC_SRC = eflags;
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fadd_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST0 = floatx80_add(ST0, FT0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fmul_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST0 = floatx80_mul(ST0, FT0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fsub_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST0 = floatx80_sub(ST0, FT0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fsubr_ST0_FT0(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST0 = floatx80_sub(FT0, ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fdiv_ST0_FT0(CPUX86State *env)
{
ST0 = helper_fdiv(env, ST0, FT0);
}
void helper_fdivr_ST0_FT0(CPUX86State *env)
{
ST0 = helper_fdiv(env, FT0, ST0);
}
/* fp operations between STN and ST0 */
void helper_fadd_STN_ST0(CPUX86State *env, int st_index)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST(st_index) = floatx80_add(ST(st_index), ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fmul_STN_ST0(CPUX86State *env, int st_index)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST(st_index) = floatx80_mul(ST(st_index), ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fsub_STN_ST0(CPUX86State *env, int st_index)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST(st_index) = floatx80_sub(ST(st_index), ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fsubr_STN_ST0(CPUX86State *env, int st_index)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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ST(st_index) = floatx80_sub(ST0, ST(st_index), &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fdiv_STN_ST0(CPUX86State *env, int st_index)
{
floatx80 *p;
p = &ST(st_index);
*p = helper_fdiv(env, *p, ST0);
}
void helper_fdivr_STN_ST0(CPUX86State *env, int st_index)
{
floatx80 *p;
p = &ST(st_index);
*p = helper_fdiv(env, ST0, *p);
}
/* misc FPU operations */
void helper_fchs_ST0(CPUX86State *env)
{
ST0 = floatx80_chs(ST0);
}
void helper_fabs_ST0(CPUX86State *env)
{
ST0 = floatx80_abs(ST0);
}
void helper_fld1_ST0(CPUX86State *env)
{
ST0 = floatx80_one;
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}
void helper_fldl2t_ST0(CPUX86State *env)
{
switch (env->fpuc & FPU_RC_MASK) {
case FPU_RC_UP:
ST0 = floatx80_l2t_u;
break;
default:
ST0 = floatx80_l2t;
break;
}
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}
void helper_fldl2e_ST0(CPUX86State *env)
{
switch (env->fpuc & FPU_RC_MASK) {
case FPU_RC_DOWN:
case FPU_RC_CHOP:
ST0 = floatx80_l2e_d;
break;
default:
ST0 = floatx80_l2e;
break;
}
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}
void helper_fldpi_ST0(CPUX86State *env)
{
switch (env->fpuc & FPU_RC_MASK) {
case FPU_RC_DOWN:
case FPU_RC_CHOP:
ST0 = floatx80_pi_d;
break;
default:
ST0 = floatx80_pi;
break;
}
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}
void helper_fldlg2_ST0(CPUX86State *env)
{
switch (env->fpuc & FPU_RC_MASK) {
case FPU_RC_DOWN:
case FPU_RC_CHOP:
ST0 = floatx80_lg2_d;
break;
default:
ST0 = floatx80_lg2;
break;
}
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}
void helper_fldln2_ST0(CPUX86State *env)
{
switch (env->fpuc & FPU_RC_MASK) {
case FPU_RC_DOWN:
case FPU_RC_CHOP:
ST0 = floatx80_ln2_d;
break;
default:
ST0 = floatx80_ln2;
break;
}
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}
void helper_fldz_ST0(CPUX86State *env)
{
ST0 = floatx80_zero;
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}
void helper_fldz_FT0(CPUX86State *env)
{
FT0 = floatx80_zero;
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}
uint32_t helper_fnstsw(CPUX86State *env)
{
return (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
}
uint32_t helper_fnstcw(CPUX86State *env)
{
return env->fpuc;
}
void update_fp_status(CPUX86State *env)
{
int rnd_type;
/* set rounding mode */
switch (env->fpuc & FPU_RC_MASK) {
default:
case FPU_RC_NEAR:
rnd_type = float_round_nearest_even;
break;
case FPU_RC_DOWN:
rnd_type = float_round_down;
break;
case FPU_RC_UP:
rnd_type = float_round_up;
break;
case FPU_RC_CHOP:
rnd_type = float_round_to_zero;
break;
}
set_float_rounding_mode(rnd_type, &env->fp_status);
switch ((env->fpuc >> 8) & 3) {
case 0:
rnd_type = 32;
break;
case 2:
rnd_type = 64;
break;
case 3:
default:
rnd_type = 80;
break;
}
set_floatx80_rounding_precision(rnd_type, &env->fp_status);
}
void helper_fldcw(CPUX86State *env, uint32_t val)
{
cpu_set_fpuc(env, val);
}
void helper_fclex(CPUX86State *env)
{
env->fpus &= 0x7f00;
}
void helper_fwait(CPUX86State *env)
{
if (env->fpus & FPUS_SE) {
fpu_raise_exception(env, GETPC());
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}
}
void helper_fninit(CPUX86State *env)
{
env->fpus = 0;
env->fpstt = 0;
cpu_set_fpuc(env, 0x37f);
env->fptags[0] = 1;
env->fptags[1] = 1;
env->fptags[2] = 1;
env->fptags[3] = 1;
env->fptags[4] = 1;
env->fptags[5] = 1;
env->fptags[6] = 1;
env->fptags[7] = 1;
}
/* BCD ops */
void helper_fbld_ST0(CPUX86State *env, target_ulong ptr)
{
floatx80 tmp;
uint64_t val;
unsigned int v;
int i;
val = 0;
for (i = 8; i >= 0; i--) {
v = cpu_ldub_data_ra(env, ptr + i, GETPC());
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val = (val * 100) + ((v >> 4) * 10) + (v & 0xf);
}
tmp = int64_to_floatx80(val, &env->fp_status);
if (cpu_ldub_data_ra(env, ptr + 9, GETPC()) & 0x80) {
tmp = floatx80_chs(tmp);
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}
fpush(env);
ST0 = tmp;
}
void helper_fbst_ST0(CPUX86State *env, target_ulong ptr)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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int v;
target_ulong mem_ref, mem_end;
int64_t val;
CPU_LDoubleU temp;
temp.d = ST0;
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val = floatx80_to_int64(ST0, &env->fp_status);
mem_ref = ptr;
if (val >= 1000000000000000000LL || val <= -1000000000000000000LL) {
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
set_float_exception_flags(float_flag_invalid, &env->fp_status);
while (mem_ref < ptr + 7) {
cpu_stb_data_ra(env, mem_ref++, 0, GETPC());
}
cpu_stb_data_ra(env, mem_ref++, 0xc0, GETPC());
cpu_stb_data_ra(env, mem_ref++, 0xff, GETPC());
cpu_stb_data_ra(env, mem_ref++, 0xff, GETPC());
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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merge_exception_flags(env, old_flags);
return;
}
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mem_end = mem_ref + 9;
if (SIGND(temp)) {
cpu_stb_data_ra(env, mem_end, 0x80, GETPC());
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val = -val;
} else {
cpu_stb_data_ra(env, mem_end, 0x00, GETPC());
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}
while (mem_ref < mem_end) {
if (val == 0) {
break;
}
v = val % 100;
val = val / 100;
v = ((v / 10) << 4) | (v % 10);
cpu_stb_data_ra(env, mem_ref++, v, GETPC());
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}
while (mem_ref < mem_end) {
cpu_stb_data_ra(env, mem_ref++, 0, GETPC());
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}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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merge_exception_flags(env, old_flags);
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}
target/i386: reimplement f2xm1 using floatx80 operations The x87 f2xm1 emulation is currently based around conversion to double. This is inherently unsuitable for a good emulation of any floatx80 operation, even before considering that it is a particularly naive implementation using double (computing with pow and then subtracting 1 rather than attempting a better emulation using expm1). Reimplement using the soft-float operations, including additions and multiplications with higher precision where appropriate to limit accumulation of errors. I considered reusing some of the m68k code for transcendental operations, but the instructions don't generally correspond exactly to x87 operations (for example, m68k has 2^x and e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors from applying multiple such operations each rounding to floatx80 precision, I wrote a direct implementation of 2^x - 1 instead. It would be possible in principle to make the implementation more efficient by doing the intermediate operations directly with significands, signs and exponents and not packing / unpacking floatx80 format for each operation, but that would make it significantly more complicated and it's not clear that's worthwhile; the m68k emulation doesn't try to do that. A test is included with many randomly generated inputs. The assumption of the test is that the result in round-to-nearest mode should always be one of the two closest floating-point numbers to the mathematical value of 2^x - 1; the implementation aims to do somewhat better than that (about 70 correct bits before rounding). I haven't investigated how accurate hardware is. Backports commit eca30647fc078f4d9ed1b455bd67960f99dbeb7a from qemu
2021-02-25 18:22:50 +00:00
/* 128-bit significand of log(2). */
#define ln2_sig_high 0xb17217f7d1cf79abULL
#define ln2_sig_low 0xc9e3b39803f2f6afULL
/*
* Polynomial coefficients for an approximation to (2^x - 1) / x, on
* the interval [-1/64, 1/64].
*/
#define f2xm1_coeff_0 make_floatx80(0x3ffe, 0xb17217f7d1cf79acULL)
#define f2xm1_coeff_0_low make_floatx80(0xbfbc, 0xd87edabf495b3762ULL)
#define f2xm1_coeff_1 make_floatx80(0x3ffc, 0xf5fdeffc162c7543ULL)
#define f2xm1_coeff_2 make_floatx80(0x3ffa, 0xe35846b82505fcc7ULL)
#define f2xm1_coeff_3 make_floatx80(0x3ff8, 0x9d955b7dd273b899ULL)
#define f2xm1_coeff_4 make_floatx80(0x3ff5, 0xaec3ff3c4ef4ac0cULL)
#define f2xm1_coeff_5 make_floatx80(0x3ff2, 0xa184897c3a7f0de9ULL)
#define f2xm1_coeff_6 make_floatx80(0x3fee, 0xffe634d0ec30d504ULL)
#define f2xm1_coeff_7 make_floatx80(0x3feb, 0xb160111d2db515e4ULL)
struct f2xm1_data {
/*
* A value very close to a multiple of 1/32, such that 2^t and 2^t - 1
* are very close to exact floatx80 values.
*/
floatx80 t;
/* The value of 2^t. */
floatx80 exp2;
/* The value of 2^t - 1. */
floatx80 exp2m1;
};
static const struct f2xm1_data f2xm1_table[65] = {
{ make_floatx80(0xbfff, 0x8000000000000000ULL),
make_floatx80(0x3ffe, 0x8000000000000000ULL),
make_floatx80(0xbffe, 0x8000000000000000ULL) },
{ make_floatx80(0xbffe, 0xf800000000002e7eULL),
make_floatx80(0x3ffe, 0x82cd8698ac2b9160ULL),
make_floatx80(0xbffd, 0xfa64f2cea7a8dd40ULL) },
{ make_floatx80(0xbffe, 0xefffffffffffe960ULL),
make_floatx80(0x3ffe, 0x85aac367cc488345ULL),
make_floatx80(0xbffd, 0xf4aa7930676ef976ULL) },
{ make_floatx80(0xbffe, 0xe800000000006f10ULL),
make_floatx80(0x3ffe, 0x88980e8092da5c14ULL),
make_floatx80(0xbffd, 0xeecfe2feda4b47d8ULL) },
{ make_floatx80(0xbffe, 0xe000000000008a45ULL),
make_floatx80(0x3ffe, 0x8b95c1e3ea8ba2a5ULL),
make_floatx80(0xbffd, 0xe8d47c382ae8bab6ULL) },
{ make_floatx80(0xbffe, 0xd7ffffffffff8a9eULL),
make_floatx80(0x3ffe, 0x8ea4398b45cd8116ULL),
make_floatx80(0xbffd, 0xe2b78ce97464fdd4ULL) },
{ make_floatx80(0xbffe, 0xd0000000000019a0ULL),
make_floatx80(0x3ffe, 0x91c3d373ab11b919ULL),
make_floatx80(0xbffd, 0xdc785918a9dc8dceULL) },
{ make_floatx80(0xbffe, 0xc7ffffffffff14dfULL),
make_floatx80(0x3ffe, 0x94f4efa8fef76836ULL),
make_floatx80(0xbffd, 0xd61620ae02112f94ULL) },
{ make_floatx80(0xbffe, 0xc000000000006530ULL),
make_floatx80(0x3ffe, 0x9837f0518db87fbbULL),
make_floatx80(0xbffd, 0xcf901f5ce48f008aULL) },
{ make_floatx80(0xbffe, 0xb7ffffffffff1723ULL),
make_floatx80(0x3ffe, 0x9b8d39b9d54eb74cULL),
make_floatx80(0xbffd, 0xc8e58c8c55629168ULL) },
{ make_floatx80(0xbffe, 0xb00000000000b5e1ULL),
make_floatx80(0x3ffe, 0x9ef5326091a0c366ULL),
make_floatx80(0xbffd, 0xc2159b3edcbe7934ULL) },
{ make_floatx80(0xbffe, 0xa800000000006f8aULL),
make_floatx80(0x3ffe, 0xa27043030c49370aULL),
make_floatx80(0xbffd, 0xbb1f79f9e76d91ecULL) },
{ make_floatx80(0xbffe, 0x9fffffffffff816aULL),
make_floatx80(0x3ffe, 0xa5fed6a9b15171cfULL),
make_floatx80(0xbffd, 0xb40252ac9d5d1c62ULL) },
{ make_floatx80(0xbffe, 0x97ffffffffffb621ULL),
make_floatx80(0x3ffe, 0xa9a15ab4ea7c30e6ULL),
make_floatx80(0xbffd, 0xacbd4a962b079e34ULL) },
{ make_floatx80(0xbffe, 0x8fffffffffff162bULL),
make_floatx80(0x3ffe, 0xad583eea42a1b886ULL),
make_floatx80(0xbffd, 0xa54f822b7abc8ef4ULL) },
{ make_floatx80(0xbffe, 0x87ffffffffff4d34ULL),
make_floatx80(0x3ffe, 0xb123f581d2ac7b51ULL),
make_floatx80(0xbffd, 0x9db814fc5aa7095eULL) },
{ make_floatx80(0xbffe, 0x800000000000227dULL),
make_floatx80(0x3ffe, 0xb504f333f9de539dULL),
make_floatx80(0xbffd, 0x95f619980c4358c6ULL) },
{ make_floatx80(0xbffd, 0xefffffffffff3978ULL),
make_floatx80(0x3ffe, 0xb8fbaf4762fbd0a1ULL),
make_floatx80(0xbffd, 0x8e08a1713a085ebeULL) },
{ make_floatx80(0xbffd, 0xe00000000000df81ULL),
make_floatx80(0x3ffe, 0xbd08a39f580bfd8cULL),
make_floatx80(0xbffd, 0x85eeb8c14fe804e8ULL) },
{ make_floatx80(0xbffd, 0xd00000000000bccfULL),
make_floatx80(0x3ffe, 0xc12c4cca667062f6ULL),
make_floatx80(0xbffc, 0xfb4eccd6663e7428ULL) },
{ make_floatx80(0xbffd, 0xc00000000000eff0ULL),
make_floatx80(0x3ffe, 0xc5672a1155069abeULL),
make_floatx80(0xbffc, 0xea6357baabe59508ULL) },
{ make_floatx80(0xbffd, 0xb000000000000fe6ULL),
make_floatx80(0x3ffe, 0xc9b9bd866e2f234bULL),
make_floatx80(0xbffc, 0xd91909e6474372d4ULL) },
{ make_floatx80(0xbffd, 0x9fffffffffff2172ULL),
make_floatx80(0x3ffe, 0xce248c151f84bf00ULL),
make_floatx80(0xbffc, 0xc76dcfab81ed0400ULL) },
{ make_floatx80(0xbffd, 0x8fffffffffffafffULL),
make_floatx80(0x3ffe, 0xd2a81d91f12afb2bULL),
make_floatx80(0xbffc, 0xb55f89b83b541354ULL) },
{ make_floatx80(0xbffc, 0xffffffffffff81a3ULL),
make_floatx80(0x3ffe, 0xd744fccad69d7d5eULL),
make_floatx80(0xbffc, 0xa2ec0cd4a58a0a88ULL) },
{ make_floatx80(0xbffc, 0xdfffffffffff1568ULL),
make_floatx80(0x3ffe, 0xdbfbb797daf25a44ULL),
make_floatx80(0xbffc, 0x901121a0943696f0ULL) },
{ make_floatx80(0xbffc, 0xbfffffffffff68daULL),
make_floatx80(0x3ffe, 0xe0ccdeec2a94f811ULL),
make_floatx80(0xbffb, 0xf999089eab583f78ULL) },
{ make_floatx80(0xbffc, 0x9fffffffffff4690ULL),
make_floatx80(0x3ffe, 0xe5b906e77c83657eULL),
make_floatx80(0xbffb, 0xd237c8c41be4d410ULL) },
{ make_floatx80(0xbffb, 0xffffffffffff8aeeULL),
make_floatx80(0x3ffe, 0xeac0c6e7dd24427cULL),
make_floatx80(0xbffb, 0xa9f9c8c116ddec20ULL) },
{ make_floatx80(0xbffb, 0xbfffffffffff2d18ULL),
make_floatx80(0x3ffe, 0xefe4b99bdcdb06ebULL),
make_floatx80(0xbffb, 0x80da33211927c8a8ULL) },
{ make_floatx80(0xbffa, 0xffffffffffff8ccbULL),
make_floatx80(0x3ffe, 0xf5257d152486d0f4ULL),
make_floatx80(0xbffa, 0xada82eadb792f0c0ULL) },
{ make_floatx80(0xbff9, 0xffffffffffff11feULL),
make_floatx80(0x3ffe, 0xfa83b2db722a0846ULL),
make_floatx80(0xbff9, 0xaf89a491babef740ULL) },
{ floatx80_zero,
make_floatx80(0x3fff, 0x8000000000000000ULL),
floatx80_zero },
{ make_floatx80(0x3ff9, 0xffffffffffff2680ULL),
make_floatx80(0x3fff, 0x82cd8698ac2b9f6fULL),
make_floatx80(0x3ff9, 0xb361a62b0ae7dbc0ULL) },
{ make_floatx80(0x3ffb, 0x800000000000b500ULL),
make_floatx80(0x3fff, 0x85aac367cc488345ULL),
make_floatx80(0x3ffa, 0xb5586cf9891068a0ULL) },
{ make_floatx80(0x3ffb, 0xbfffffffffff4b67ULL),
make_floatx80(0x3fff, 0x88980e8092da7cceULL),
make_floatx80(0x3ffb, 0x8980e8092da7cce0ULL) },
{ make_floatx80(0x3ffb, 0xffffffffffffff57ULL),
make_floatx80(0x3fff, 0x8b95c1e3ea8bd6dfULL),
make_floatx80(0x3ffb, 0xb95c1e3ea8bd6df0ULL) },
{ make_floatx80(0x3ffc, 0x9fffffffffff811fULL),
make_floatx80(0x3fff, 0x8ea4398b45cd4780ULL),
make_floatx80(0x3ffb, 0xea4398b45cd47800ULL) },
{ make_floatx80(0x3ffc, 0xbfffffffffff9980ULL),
make_floatx80(0x3fff, 0x91c3d373ab11b919ULL),
make_floatx80(0x3ffc, 0x8e1e9b9d588dc8c8ULL) },
{ make_floatx80(0x3ffc, 0xdffffffffffff631ULL),
make_floatx80(0x3fff, 0x94f4efa8fef70864ULL),
make_floatx80(0x3ffc, 0xa7a77d47f7b84320ULL) },
{ make_floatx80(0x3ffc, 0xffffffffffff2499ULL),
make_floatx80(0x3fff, 0x9837f0518db892d4ULL),
make_floatx80(0x3ffc, 0xc1bf828c6dc496a0ULL) },
{ make_floatx80(0x3ffd, 0x8fffffffffff80fbULL),
make_floatx80(0x3fff, 0x9b8d39b9d54e3a79ULL),
make_floatx80(0x3ffc, 0xdc69cdceaa71d3c8ULL) },
{ make_floatx80(0x3ffd, 0x9fffffffffffbc23ULL),
make_floatx80(0x3fff, 0x9ef5326091a10313ULL),
make_floatx80(0x3ffc, 0xf7a993048d081898ULL) },
{ make_floatx80(0x3ffd, 0xafffffffffff20ecULL),
make_floatx80(0x3fff, 0xa27043030c49370aULL),
make_floatx80(0x3ffd, 0x89c10c0c3124dc28ULL) },
{ make_floatx80(0x3ffd, 0xc00000000000fd2cULL),
make_floatx80(0x3fff, 0xa5fed6a9b15171cfULL),
make_floatx80(0x3ffd, 0x97fb5aa6c545c73cULL) },
{ make_floatx80(0x3ffd, 0xd0000000000093beULL),
make_floatx80(0x3fff, 0xa9a15ab4ea7c30e6ULL),
make_floatx80(0x3ffd, 0xa6856ad3a9f0c398ULL) },
{ make_floatx80(0x3ffd, 0xe00000000000c2aeULL),
make_floatx80(0x3fff, 0xad583eea42a17876ULL),
make_floatx80(0x3ffd, 0xb560fba90a85e1d8ULL) },
{ make_floatx80(0x3ffd, 0xefffffffffff1e3fULL),
make_floatx80(0x3fff, 0xb123f581d2abef6cULL),
make_floatx80(0x3ffd, 0xc48fd6074aafbdb0ULL) },
{ make_floatx80(0x3ffd, 0xffffffffffff1c23ULL),
make_floatx80(0x3fff, 0xb504f333f9de2cadULL),
make_floatx80(0x3ffd, 0xd413cccfe778b2b4ULL) },
{ make_floatx80(0x3ffe, 0x8800000000006344ULL),
make_floatx80(0x3fff, 0xb8fbaf4762fbd0a1ULL),
make_floatx80(0x3ffd, 0xe3eebd1d8bef4284ULL) },
{ make_floatx80(0x3ffe, 0x9000000000005d67ULL),
make_floatx80(0x3fff, 0xbd08a39f580c668dULL),
make_floatx80(0x3ffd, 0xf4228e7d60319a34ULL) },
{ make_floatx80(0x3ffe, 0x9800000000009127ULL),
make_floatx80(0x3fff, 0xc12c4cca6670e042ULL),
make_floatx80(0x3ffe, 0x82589994cce1c084ULL) },
{ make_floatx80(0x3ffe, 0x9fffffffffff06f9ULL),
make_floatx80(0x3fff, 0xc5672a11550655c3ULL),
make_floatx80(0x3ffe, 0x8ace5422aa0cab86ULL) },
{ make_floatx80(0x3ffe, 0xa7fffffffffff80dULL),
make_floatx80(0x3fff, 0xc9b9bd866e2f234bULL),
make_floatx80(0x3ffe, 0x93737b0cdc5e4696ULL) },
{ make_floatx80(0x3ffe, 0xafffffffffff1470ULL),
make_floatx80(0x3fff, 0xce248c151f83fd69ULL),
make_floatx80(0x3ffe, 0x9c49182a3f07fad2ULL) },
{ make_floatx80(0x3ffe, 0xb800000000000e0aULL),
make_floatx80(0x3fff, 0xd2a81d91f12aec5cULL),
make_floatx80(0x3ffe, 0xa5503b23e255d8b8ULL) },
{ make_floatx80(0x3ffe, 0xc00000000000b7faULL),
make_floatx80(0x3fff, 0xd744fccad69dd630ULL),
make_floatx80(0x3ffe, 0xae89f995ad3bac60ULL) },
{ make_floatx80(0x3ffe, 0xc800000000003aa6ULL),
make_floatx80(0x3fff, 0xdbfbb797daf25a44ULL),
make_floatx80(0x3ffe, 0xb7f76f2fb5e4b488ULL) },
{ make_floatx80(0x3ffe, 0xd00000000000a6aeULL),
make_floatx80(0x3fff, 0xe0ccdeec2a954685ULL),
make_floatx80(0x3ffe, 0xc199bdd8552a8d0aULL) },
{ make_floatx80(0x3ffe, 0xd800000000004165ULL),
make_floatx80(0x3fff, 0xe5b906e77c837155ULL),
make_floatx80(0x3ffe, 0xcb720dcef906e2aaULL) },
{ make_floatx80(0x3ffe, 0xe00000000000582cULL),
make_floatx80(0x3fff, 0xeac0c6e7dd24713aULL),
make_floatx80(0x3ffe, 0xd5818dcfba48e274ULL) },
{ make_floatx80(0x3ffe, 0xe800000000001a5dULL),
make_floatx80(0x3fff, 0xefe4b99bdcdb06ebULL),
make_floatx80(0x3ffe, 0xdfc97337b9b60dd6ULL) },
{ make_floatx80(0x3ffe, 0xefffffffffffc1efULL),
make_floatx80(0x3fff, 0xf5257d152486a2faULL),
make_floatx80(0x3ffe, 0xea4afa2a490d45f4ULL) },
{ make_floatx80(0x3ffe, 0xf800000000001069ULL),
make_floatx80(0x3fff, 0xfa83b2db722a0e5cULL),
make_floatx80(0x3ffe, 0xf50765b6e4541cb8ULL) },
{ make_floatx80(0x3fff, 0x8000000000000000ULL),
make_floatx80(0x4000, 0x8000000000000000ULL),
make_floatx80(0x3fff, 0x8000000000000000ULL) },
};
2015-08-21 07:04:50 +00:00
void helper_f2xm1(CPUX86State *env)
{
target/i386: reimplement f2xm1 using floatx80 operations The x87 f2xm1 emulation is currently based around conversion to double. This is inherently unsuitable for a good emulation of any floatx80 operation, even before considering that it is a particularly naive implementation using double (computing with pow and then subtracting 1 rather than attempting a better emulation using expm1). Reimplement using the soft-float operations, including additions and multiplications with higher precision where appropriate to limit accumulation of errors. I considered reusing some of the m68k code for transcendental operations, but the instructions don't generally correspond exactly to x87 operations (for example, m68k has 2^x and e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors from applying multiple such operations each rounding to floatx80 precision, I wrote a direct implementation of 2^x - 1 instead. It would be possible in principle to make the implementation more efficient by doing the intermediate operations directly with significands, signs and exponents and not packing / unpacking floatx80 format for each operation, but that would make it significantly more complicated and it's not clear that's worthwhile; the m68k emulation doesn't try to do that. A test is included with many randomly generated inputs. The assumption of the test is that the result in round-to-nearest mode should always be one of the two closest floating-point numbers to the mathematical value of 2^x - 1; the implementation aims to do somewhat better than that (about 70 correct bits before rounding). I haven't investigated how accurate hardware is. Backports commit eca30647fc078f4d9ed1b455bd67960f99dbeb7a from qemu
2021-02-25 18:22:50 +00:00
uint8_t old_flags = save_exception_flags(env);
uint64_t sig = extractFloatx80Frac(ST0);
int32_t exp = extractFloatx80Exp(ST0);
bool sign = extractFloatx80Sign(ST0);
if (floatx80_invalid_encoding(ST0)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_default_nan(&env->fp_status);
} else if (floatx80_is_any_nan(ST0)) {
if (floatx80_is_signaling_nan(ST0, &env->fp_status)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_silence_nan(ST0, &env->fp_status);
}
} else if (exp > 0x3fff ||
(exp == 0x3fff && sig != (0x8000000000000000ULL))) {
/* Out of range for the instruction, treat as invalid. */
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_default_nan(&env->fp_status);
} else if (exp == 0x3fff) {
/* Argument 1 or -1, exact result 1 or -0.5. */
if (sign) {
ST0 = make_floatx80(0xbffe, 0x8000000000000000ULL);
}
} else if (exp < 0x3fb0) {
if (!floatx80_is_zero(ST0)) {
/*
* Multiplying the argument by an extra-precision version
* of log(2) is sufficiently precise. Zero arguments are
* returned unchanged.
*/
uint64_t sig0, sig1, sig2;
if (exp == 0) {
normalizeFloatx80Subnormal(sig, &exp, &sig);
}
mul128By64To192(ln2_sig_high, ln2_sig_low, sig, &sig0, &sig1,
&sig2);
/* This result is inexact. */
sig1 |= 1;
ST0 = normalizeRoundAndPackFloatx80(80, sign, exp, sig0, sig1,
&env->fp_status);
}
} else {
floatx80 tmp, y, accum;
bool asign, bsign;
int32_t n, aexp, bexp;
uint64_t asig0, asig1, asig2, bsig0, bsig1;
FloatRoundMode save_mode = env->fp_status.float_rounding_mode;
signed char save_prec = env->fp_status.floatx80_rounding_precision;
env->fp_status.float_rounding_mode = float_round_nearest_even;
env->fp_status.floatx80_rounding_precision = 80;
/* Find the nearest multiple of 1/32 to the argument. */
tmp = floatx80_scalbn(ST0, 5, &env->fp_status);
n = 32 + floatx80_to_int32(tmp, &env->fp_status);
y = floatx80_sub(ST0, f2xm1_table[n].t, &env->fp_status);
if (floatx80_is_zero(y)) {
/*
* Use the value of 2^t - 1 from the table, to avoid
* needing to special-case zero as a result of
* multiplication below.
*/
ST0 = f2xm1_table[n].t;
set_float_exception_flags(float_flag_inexact, &env->fp_status);
env->fp_status.float_rounding_mode = save_mode;
} else {
/*
* Compute the lower parts of a polynomial expansion for
* (2^y - 1) / y.
*/
accum = floatx80_mul(f2xm1_coeff_7, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_6, accum, &env->fp_status);
accum = floatx80_mul(accum, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_5, accum, &env->fp_status);
accum = floatx80_mul(accum, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_4, accum, &env->fp_status);
accum = floatx80_mul(accum, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_3, accum, &env->fp_status);
accum = floatx80_mul(accum, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_2, accum, &env->fp_status);
accum = floatx80_mul(accum, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_1, accum, &env->fp_status);
accum = floatx80_mul(accum, y, &env->fp_status);
accum = floatx80_add(f2xm1_coeff_0_low, accum, &env->fp_status);
/*
* The full polynomial expansion is f2xm1_coeff_0 + accum
* (where accum has much lower magnitude, and so, in
* particular, carry out of the addition is not possible).
* (This expansion is only accurate to about 70 bits, not
* 128 bits.)
*/
aexp = extractFloatx80Exp(f2xm1_coeff_0);
asign = extractFloatx80Sign(f2xm1_coeff_0);
shift128RightJamming(extractFloatx80Frac(accum), 0,
aexp - extractFloatx80Exp(accum),
&asig0, &asig1);
bsig0 = extractFloatx80Frac(f2xm1_coeff_0);
bsig1 = 0;
if (asign == extractFloatx80Sign(accum)) {
add128(bsig0, bsig1, asig0, asig1, &asig0, &asig1);
} else {
sub128(bsig0, bsig1, asig0, asig1, &asig0, &asig1);
}
/* And thus compute an approximation to 2^y - 1. */
mul128By64To192(asig0, asig1, extractFloatx80Frac(y),
&asig0, &asig1, &asig2);
aexp += extractFloatx80Exp(y) - 0x3ffe;
asign ^= extractFloatx80Sign(y);
if (n != 32) {
/*
* Multiply this by the precomputed value of 2^t and
* add that of 2^t - 1.
*/
mul128By64To192(asig0, asig1,
extractFloatx80Frac(f2xm1_table[n].exp2),
&asig0, &asig1, &asig2);
aexp += extractFloatx80Exp(f2xm1_table[n].exp2) - 0x3ffe;
bexp = extractFloatx80Exp(f2xm1_table[n].exp2m1);
bsig0 = extractFloatx80Frac(f2xm1_table[n].exp2m1);
bsig1 = 0;
if (bexp < aexp) {
shift128RightJamming(bsig0, bsig1, aexp - bexp,
&bsig0, &bsig1);
} else if (aexp < bexp) {
shift128RightJamming(asig0, asig1, bexp - aexp,
&asig0, &asig1);
aexp = bexp;
}
/* The sign of 2^t - 1 is always that of the result. */
bsign = extractFloatx80Sign(f2xm1_table[n].exp2m1);
if (asign == bsign) {
/* Avoid possible carry out of the addition. */
shift128RightJamming(asig0, asig1, 1,
&asig0, &asig1);
shift128RightJamming(bsig0, bsig1, 1,
&bsig0, &bsig1);
++aexp;
add128(asig0, asig1, bsig0, bsig1, &asig0, &asig1);
} else {
sub128(bsig0, bsig1, asig0, asig1, &asig0, &asig1);
asign = bsign;
}
}
env->fp_status.float_rounding_mode = save_mode;
/* This result is inexact. */
asig1 |= 1;
ST0 = normalizeRoundAndPackFloatx80(80, asign, aexp, asig0, asig1,
&env->fp_status);
}
2015-08-21 07:04:50 +00:00
target/i386: reimplement f2xm1 using floatx80 operations The x87 f2xm1 emulation is currently based around conversion to double. This is inherently unsuitable for a good emulation of any floatx80 operation, even before considering that it is a particularly naive implementation using double (computing with pow and then subtracting 1 rather than attempting a better emulation using expm1). Reimplement using the soft-float operations, including additions and multiplications with higher precision where appropriate to limit accumulation of errors. I considered reusing some of the m68k code for transcendental operations, but the instructions don't generally correspond exactly to x87 operations (for example, m68k has 2^x and e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors from applying multiple such operations each rounding to floatx80 precision, I wrote a direct implementation of 2^x - 1 instead. It would be possible in principle to make the implementation more efficient by doing the intermediate operations directly with significands, signs and exponents and not packing / unpacking floatx80 format for each operation, but that would make it significantly more complicated and it's not clear that's worthwhile; the m68k emulation doesn't try to do that. A test is included with many randomly generated inputs. The assumption of the test is that the result in round-to-nearest mode should always be one of the two closest floating-point numbers to the mathematical value of 2^x - 1; the implementation aims to do somewhat better than that (about 70 correct bits before rounding). I haven't investigated how accurate hardware is. Backports commit eca30647fc078f4d9ed1b455bd67960f99dbeb7a from qemu
2021-02-25 18:22:50 +00:00
env->fp_status.floatx80_rounding_precision = save_prec;
}
merge_exception_flags(env, old_flags);
2015-08-21 07:04:50 +00:00
}
void helper_fyl2x(CPUX86State *env)
{
double fptemp = floatx80_to_double(env, ST0);
if (fptemp > 0.0) {
fptemp = log(fptemp) / log(2.0); /* log2(ST) */
fptemp *= floatx80_to_double(env, ST1);
ST1 = double_to_floatx80(env, fptemp);
fpop(env);
} else {
env->fpus &= ~0x4700;
env->fpus |= 0x400;
}
}
void helper_fptan(CPUX86State *env)
{
double fptemp = floatx80_to_double(env, ST0);
if ((fptemp > MAXTAN) || (fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
fptemp = tan(fptemp);
2015-08-21 07:04:50 +00:00
ST0 = double_to_floatx80(env, fptemp);
fpush(env);
ST0 = floatx80_one;
2015-08-21 07:04:50 +00:00
env->fpus &= ~0x400; /* C2 <-- 0 */
/* the above code is for |arg| < 2**52 only */
}
}
void helper_fpatan(CPUX86State *env)
{
double fptemp, fpsrcop;
fpsrcop = floatx80_to_double(env, ST1);
fptemp = floatx80_to_double(env, ST0);
ST1 = double_to_floatx80(env, atan2(fpsrcop, fptemp));
fpop(env);
}
void helper_fxtract(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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CPU_LDoubleU temp;
temp.d = ST0;
if (floatx80_is_zero(ST0)) {
/* Easy way to generate -inf and raising division by 0 exception */
ST0 = floatx80_div(floatx80_chs(floatx80_one), floatx80_zero,
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&env->fp_status);
fpush(env);
ST0 = temp.d;
} else if (floatx80_invalid_encoding(ST0)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_default_nan(&env->fp_status);
fpush(env);
ST0 = ST1;
} else if (floatx80_is_any_nan(ST0)) {
if (floatx80_is_signaling_nan(ST0, &env->fp_status)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_silence_nan(ST0, &env->fp_status);
}
fpush(env);
ST0 = ST1;
} else if (floatx80_is_infinity(ST0)) {
fpush(env);
ST0 = ST1;
ST1 = floatx80_infinity;
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} else {
int expdif;
if (EXPD(temp) == 0) {
int shift = clz64(temp.l.lower);
temp.l.lower <<= shift;
expdif = 1 - EXPBIAS - shift;
float_raise(float_flag_input_denormal, &env->fp_status);
} else {
expdif = EXPD(temp) - EXPBIAS;
}
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/* DP exponent bias */
ST0 = int32_to_floatx80(expdif, &env->fp_status);
fpush(env);
BIASEXPONENT(temp);
ST0 = temp.d;
}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
merge_exception_flags(env, old_flags);
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}
void helper_fprem1(CPUX86State *env)
{
double st0, st1, dblq, fpsrcop, fptemp;
CPU_LDoubleU fpsrcop1, fptemp1;
int expdif;
signed long long int q;
st0 = floatx80_to_double(env, ST0);
st1 = floatx80_to_double(env, ST1);
if (isinf(st0) || isnan(st0) || isnan(st1) || (st1 == 0.0)) {
ST0 = double_to_floatx80(env, 0.0 / 0.0); /* NaN */
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env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
return;
}
fpsrcop = st0;
fptemp = st1;
fpsrcop1.d = ST0;
fptemp1.d = ST1;
expdif = EXPD(fpsrcop1) - EXPD(fptemp1);
if (expdif < 0) {
/* optimisation? taken from the AMD docs */
env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
/* ST0 is unchanged */
return;
}
if (expdif < 53) {
dblq = fpsrcop / fptemp;
/* round dblq towards nearest integer */
dblq = rint(dblq);
st0 = fpsrcop - fptemp * dblq;
/* convert dblq to q by truncating towards zero */
if (dblq < 0.0) {
q = (signed long long int)(-dblq);
} else {
q = (signed long long int)dblq;
}
env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
/* (C0,C3,C1) <-- (q2,q1,q0) */
env->fpus |= (q & 0x4) << (8 - 2); /* (C0) <-- q2 */
env->fpus |= (q & 0x2) << (14 - 1); /* (C3) <-- q1 */
env->fpus |= (q & 0x1) << (9 - 0); /* (C1) <-- q0 */
} else {
env->fpus |= 0x400; /* C2 <-- 1 */
fptemp = pow(2.0, expdif - 50);
fpsrcop = (st0 / st1) / fptemp;
/* fpsrcop = integer obtained by chopping */
fpsrcop = (fpsrcop < 0.0) ?
-(floor(fabs(fpsrcop))) : floor(fpsrcop);
st0 -= (st1 * fpsrcop * fptemp);
}
ST0 = double_to_floatx80(env, st0);
}
void helper_fprem(CPUX86State *env)
{
double st0, st1, dblq, fpsrcop, fptemp;
CPU_LDoubleU fpsrcop1, fptemp1;
int expdif;
signed long long int q;
st0 = floatx80_to_double(env, ST0);
st1 = floatx80_to_double(env, ST1);
if (isinf(st0) || isnan(st0) || isnan(st1) || (st1 == 0.0)) {
ST0 = double_to_floatx80(env, 0.0 / 0.0); /* NaN */
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env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
return;
}
fpsrcop = st0;
fptemp = st1;
fpsrcop1.d = ST0;
fptemp1.d = ST1;
expdif = EXPD(fpsrcop1) - EXPD(fptemp1);
if (expdif < 0) {
/* optimisation? taken from the AMD docs */
env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
/* ST0 is unchanged */
return;
}
if (expdif < 53) {
dblq = fpsrcop / fptemp; /* ST0 / ST1 */
/* round dblq towards zero */
dblq = (dblq < 0.0) ? ceil(dblq) : floor(dblq);
st0 = fpsrcop - fptemp * dblq; /* fpsrcop is ST0 */
/* convert dblq to q by truncating towards zero */
if (dblq < 0.0) {
q = (signed long long int)(-dblq);
} else {
q = (signed long long int)dblq;
}
env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
/* (C0,C3,C1) <-- (q2,q1,q0) */
env->fpus |= (q & 0x4) << (8 - 2); /* (C0) <-- q2 */
env->fpus |= (q & 0x2) << (14 - 1); /* (C3) <-- q1 */
env->fpus |= (q & 0x1) << (9 - 0); /* (C1) <-- q0 */
} else {
int N = 32 + (expdif % 32); /* as per AMD docs */
env->fpus |= 0x400; /* C2 <-- 1 */
fptemp = pow(2.0, (double)(expdif - N));
fpsrcop = (st0 / st1) / fptemp;
/* fpsrcop = integer obtained by chopping */
fpsrcop = (fpsrcop < 0.0) ?
-(floor(fabs(fpsrcop))) : floor(fpsrcop);
st0 -= (st1 * fpsrcop * fptemp);
}
ST0 = double_to_floatx80(env, st0);
}
void helper_fyl2xp1(CPUX86State *env)
{
double fptemp = floatx80_to_double(env, ST0);
if ((fptemp + 1.0) > 0.0) {
fptemp = log(fptemp + 1.0) / log(2.0); /* log2(ST + 1.0) */
fptemp *= floatx80_to_double(env, ST1);
ST1 = double_to_floatx80(env, fptemp);
fpop(env);
} else {
env->fpus &= ~0x4700;
env->fpus |= 0x400;
}
}
void helper_fsqrt(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
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if (floatx80_is_neg(ST0)) {
env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
env->fpus |= 0x400;
}
ST0 = floatx80_sqrt(ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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merge_exception_flags(env, old_flags);
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}
void helper_fsincos(CPUX86State *env)
{
double fptemp = floatx80_to_double(env, ST0);
if ((fptemp > MAXTAN) || (fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = double_to_floatx80(env, sin(fptemp));
fpush(env);
ST0 = double_to_floatx80(env, cos(fptemp));
env->fpus &= ~0x400; /* C2 <-- 0 */
/* the above code is for |arg| < 2**63 only */
}
}
void helper_frndint(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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uint8_t old_flags = save_exception_flags(env);
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ST0 = floatx80_round_to_int(ST0, &env->fp_status);
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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merge_exception_flags(env, old_flags);
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}
void helper_fscale(CPUX86State *env)
{
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t old_flags = save_exception_flags(env);
if (floatx80_invalid_encoding(ST1) || floatx80_invalid_encoding(ST0)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_default_nan(&env->fp_status);
} else if (floatx80_is_any_nan(ST1)) {
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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if (floatx80_is_signaling_nan(ST0, &env->fp_status)) {
float_raise(float_flag_invalid, &env->fp_status);
}
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ST0 = ST1;
if (floatx80_is_signaling_nan(ST0, &env->fp_status)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_silence_nan(ST0, &env->fp_status);
}
} else if (floatx80_is_infinity(ST1) &&
!floatx80_invalid_encoding(ST0) &&
!floatx80_is_any_nan(ST0)) {
if (floatx80_is_neg(ST1)) {
if (floatx80_is_infinity(ST0)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_default_nan(&env->fp_status);
} else {
ST0 = (floatx80_is_neg(ST0) ?
floatx80_chs(floatx80_zero) :
floatx80_zero);
}
} else {
if (floatx80_is_zero(ST0)) {
float_raise(float_flag_invalid, &env->fp_status);
ST0 = floatx80_default_nan(&env->fp_status);
} else {
ST0 = (floatx80_is_neg(ST0) ?
floatx80_chs(floatx80_infinity) :
floatx80_infinity);
}
}
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} else {
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
int n;
signed char save = env->fp_status.floatx80_rounding_precision;
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
2020-06-15 17:19:25 +00:00
uint8_t save_flags = get_float_exception_flags(&env->fp_status);
set_float_exception_flags(0, &env->fp_status);
n = floatx80_to_int32_round_to_zero(ST1, &env->fp_status);
set_float_exception_flags(save_flags, &env->fp_status);
env->fp_status.floatx80_rounding_precision = 80;
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ST0 = floatx80_scalbn(ST0, n, &env->fp_status);
env->fp_status.floatx80_rounding_precision = save;
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}
target/i386: fix IEEE x87 floating-point exception raising Most x87 instruction implementations fail to raise the expected IEEE floating-point exceptions because they do nothing to convert the exception state from the softfloat machinery into the exception flags in the x87 status word. There is special-case handling of division to raise the divide-by-zero exception, but that handling is itself buggy: it raises the exception in inappropriate cases (inf / 0 and nan / 0, which should not raise any exceptions, and 0 / 0, which should raise "invalid" instead). Fix this by converting the floating-point exceptions raised during an operation by the softfloat machinery into exceptions in the x87 status word (passing through the existing fpu_set_exception function for handling related to trapping exceptions). There are special cases where some functions convert to integer internally but exceptions from that conversion are not always correct exceptions for the instruction to raise. There might be scope for some simplification if the softfloat exception state either could always be assumed to be in sync with the state in the status word, or could always be ignored at the start of each instruction and just set to 0 then; I haven't looked into that in detail, and it might run into interactions with the various ways the emulation does not yet handle trapping exceptions properly. I think the approach taken here, of saving the softfloat state, setting exceptions there to 0 and then merging the old exceptions back in after carrying out the operation, is conservatively safe Backports commit 975af797f1e04e4d1b1a12f1731141d3770fdbce from qemu
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merge_exception_flags(env, old_flags);
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}
void helper_fsin(CPUX86State *env)
{
double fptemp = floatx80_to_double(env, ST0);
if ((fptemp > MAXTAN) || (fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = double_to_floatx80(env, sin(fptemp));
env->fpus &= ~0x400; /* C2 <-- 0 */
/* the above code is for |arg| < 2**53 only */
}
}
void helper_fcos(CPUX86State *env)
{
double fptemp = floatx80_to_double(env, ST0);
if ((fptemp > MAXTAN) || (fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = double_to_floatx80(env, cos(fptemp));
env->fpus &= ~0x400; /* C2 <-- 0 */
/* the above code is for |arg| < 2**63 only */
}
}
void helper_fxam_ST0(CPUX86State *env)
{
CPU_LDoubleU temp;
int expdif;
temp.d = ST0;
env->fpus &= ~0x4700; /* (C3,C2,C1,C0) <-- 0000 */
if (SIGND(temp)) {
env->fpus |= 0x200; /* C1 <-- 1 */
}
if (env->fptags[env->fpstt]) {
env->fpus |= 0x4100; /* Empty */
return;
}
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expdif = EXPD(temp);
if (expdif == MAXEXPD) {
if (MANTD(temp) == 0x8000000000000000ULL) {
env->fpus |= 0x500; /* Infinity */
} else if (MANTD(temp) & 0x8000000000000000ULL) {
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env->fpus |= 0x100; /* NaN */
}
} else if (expdif == 0) {
if (MANTD(temp) == 0) {
env->fpus |= 0x4000; /* Zero */
} else {
env->fpus |= 0x4400; /* Denormal */
}
} else if (MANTD(temp) & 0x8000000000000000ULL) {
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env->fpus |= 0x400;
}
}
static void do_fstenv(CPUX86State *env, target_ulong ptr, int data32,
uintptr_t retaddr)
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{
int fpus, fptag, exp, i;
uint64_t mant;
CPU_LDoubleU tmp;
fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
fptag = 0;
for (i = 7; i >= 0; i--) {
fptag <<= 2;
if (env->fptags[i]) {
fptag |= 3;
} else {
tmp.d = env->fpregs[i].d;
exp = EXPD(tmp);
mant = MANTD(tmp);
if (exp == 0 && mant == 0) {
/* zero */
fptag |= 1;
} else if (exp == 0 || exp == MAXEXPD
|| (mant & (1LL << 63)) == 0) {
/* NaNs, infinity, denormal */
fptag |= 2;
}
}
}
if (data32) {
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/* 32 bit */
cpu_stl_data_ra(env, ptr, env->fpuc, retaddr);
cpu_stl_data_ra(env, ptr + 4, fpus, retaddr);
cpu_stl_data_ra(env, ptr + 8, fptag, retaddr);
cpu_stl_data_ra(env, ptr + 12, 0, retaddr); /* fpip */
cpu_stl_data_ra(env, ptr + 16, 0, retaddr); /* fpcs */
cpu_stl_data_ra(env, ptr + 20, 0, retaddr); /* fpoo */
cpu_stl_data_ra(env, ptr + 24, 0, retaddr); /* fpos */
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} else {
/* 16 bit */
cpu_stw_data_ra(env, ptr, env->fpuc, retaddr);
cpu_stw_data_ra(env, ptr + 2, fpus, retaddr);
cpu_stw_data_ra(env, ptr + 4, fptag, retaddr);
cpu_stw_data_ra(env, ptr + 6, 0, retaddr);
cpu_stw_data_ra(env, ptr + 8, 0, retaddr);
cpu_stw_data_ra(env, ptr + 10, 0, retaddr);
cpu_stw_data_ra(env, ptr + 12, 0, retaddr);
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}
}
void helper_fstenv(CPUX86State *env, target_ulong ptr, int data32)
{
do_fstenv(env, ptr, data32, GETPC());
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}
static void do_fldenv(CPUX86State *env, target_ulong ptr, int data32,
uintptr_t retaddr)
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{
int i, fpus, fptag;
if (data32) {
cpu_set_fpuc(env, cpu_lduw_data_ra(env, ptr, retaddr));
fpus = cpu_lduw_data_ra(env, ptr + 4, retaddr);
fptag = cpu_lduw_data_ra(env, ptr + 8, retaddr);
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} else {
cpu_set_fpuc(env, cpu_lduw_data_ra(env, ptr, retaddr));
fpus = cpu_lduw_data_ra(env, ptr + 2, retaddr);
fptag = cpu_lduw_data_ra(env, ptr + 4, retaddr);
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}
env->fpstt = (fpus >> 11) & 7;
env->fpus = fpus & ~0x3800;
for (i = 0; i < 8; i++) {
env->fptags[i] = ((fptag & 3) == 3);
fptag >>= 2;
}
}
void helper_fldenv(CPUX86State *env, target_ulong ptr, int data32)
{
do_fldenv(env, ptr, data32, GETPC());
}
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void helper_fsave(CPUX86State *env, target_ulong ptr, int data32)
{
floatx80 tmp;
int i;
do_fstenv(env, ptr, data32, GETPC());
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ptr += (14 << data32);
for (i = 0; i < 8; i++) {
tmp = ST(i);
helper_fstt(env, tmp, ptr, GETPC());
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ptr += 10;
}
/* fninit */
env->fpus = 0;
env->fpstt = 0;
cpu_set_fpuc(env, 0x37f);
env->fptags[0] = 1;
env->fptags[1] = 1;
env->fptags[2] = 1;
env->fptags[3] = 1;
env->fptags[4] = 1;
env->fptags[5] = 1;
env->fptags[6] = 1;
env->fptags[7] = 1;
}
void helper_frstor(CPUX86State *env, target_ulong ptr, int data32)
{
floatx80 tmp;
int i;
do_fldenv(env, ptr, data32, GETPC());
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ptr += (14 << data32);
for (i = 0; i < 8; i++) {
tmp = helper_fldt(env, ptr, GETPC());
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ST(i) = tmp;
ptr += 10;
}
}
#if defined(CONFIG_USER_ONLY)
void cpu_x86_fsave(CPUX86State *env, target_ulong ptr, int data32)
{
helper_fsave(env, ptr, data32);
}
void cpu_x86_frstor(CPUX86State *env, target_ulong ptr, int data32)
{
helper_frstor(env, ptr, data32);
}
#endif
#define XO(X) offsetof(X86XSaveArea, X)
static void do_xsave_fpu(CPUX86State *env, target_ulong ptr, uintptr_t ra)
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{
int fpus, fptag, i;
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target_ulong addr;
fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
fptag = 0;
for (i = 0; i < 8; i++) {
fptag |= (env->fptags[i] << i);
}
cpu_stw_data_ra(env, ptr + XO(legacy.fcw), env->fpuc, ra);
cpu_stw_data_ra(env, ptr + XO(legacy.fsw), fpus, ra);
cpu_stw_data_ra(env, ptr + XO(legacy.ftw), fptag ^ 0xff, ra);
/* In 32-bit mode this is eip, sel, dp, sel.
In 64-bit mode this is rip, rdp.
But in either case we don't write actual data, just zeros. */
cpu_stq_data_ra(env, ptr + XO(legacy.fpip), 0, ra); /* eip+sel; rip */
cpu_stq_data_ra(env, ptr + XO(legacy.fpdp), 0, ra); /* edp+sel; rdp */
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addr = ptr + XO(legacy.fpregs);
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for (i = 0; i < 8; i++) {
floatx80 tmp = ST(i);
helper_fstt(env, tmp, addr, ra);
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addr += 16;
}
}
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static void do_xsave_mxcsr(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
cpu_stl_data_ra(env, ptr + XO(legacy.mxcsr), env->mxcsr, ra);
cpu_stl_data_ra(env, ptr + XO(legacy.mxcsr_mask), 0x0000ffff, ra);
}
static void do_xsave_sse(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
int i, nb_xmm_regs;
target_ulong addr;
if (env->hflags & HF_CS64_MASK) {
nb_xmm_regs = 16;
} else {
nb_xmm_regs = 8;
}
addr = ptr + XO(legacy.xmm_regs);
for (i = 0; i < nb_xmm_regs; i++) {
cpu_stq_data_ra(env, addr, env->xmm_regs[i].ZMM_Q(0), ra);
cpu_stq_data_ra(env, addr + 8, env->xmm_regs[i].ZMM_Q(1), ra);
addr += 16;
}
}
static void do_xsave_bndregs(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
target_ulong addr = ptr + offsetof(XSaveBNDREG, bnd_regs);
int i;
for (i = 0; i < 4; i++, addr += 16) {
cpu_stq_data_ra(env, addr, env->bnd_regs[i].lb, ra);
cpu_stq_data_ra(env, addr + 8, env->bnd_regs[i].ub, ra);
}
}
static void do_xsave_bndcsr(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
cpu_stq_data_ra(env, ptr + offsetof(XSaveBNDCSR, bndcsr.cfgu),
env->bndcs_regs.cfgu, ra);
cpu_stq_data_ra(env, ptr + offsetof(XSaveBNDCSR, bndcsr.sts),
env->bndcs_regs.sts, ra);
}
static void do_xsave_pkru(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
cpu_stq_data_ra(env, ptr, env->pkru, ra);
}
void helper_fxsave(CPUX86State *env, target_ulong ptr)
{
uintptr_t ra = GETPC();
/* The operand must be 16 byte aligned */
if (ptr & 0xf) {
raise_exception_ra(env, EXCP0D_GPF, ra);
}
do_xsave_fpu(env, ptr, ra);
if (env->cr[4] & CR4_OSFXSR_MASK) {
do_xsave_mxcsr(env, ptr, ra);
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/* Fast FXSAVE leaves out the XMM registers */
if (!(env->efer & MSR_EFER_FFXSR)
|| (env->hflags & HF_CPL_MASK)
|| !(env->hflags & HF_LMA_MASK)) {
do_xsave_sse(env, ptr, ra);
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}
}
}
static uint64_t get_xinuse(CPUX86State *env)
{
uint64_t inuse = -1;
/* For the most part, we don't track XINUSE. We could calculate it
here for all components, but it's probably less work to simply
indicate in use. That said, the state of BNDREGS is important
enough to track in HFLAGS, so we might as well use that here. */
if ((env->hflags & HF_MPX_IU_MASK) == 0) {
inuse &= ~XSTATE_BNDREGS_MASK;
}
return inuse;
}
static void do_xsave(CPUX86State *env, target_ulong ptr, uint64_t rfbm,
uint64_t inuse, uint64_t opt, uintptr_t ra)
{
uint64_t old_bv, new_bv;
/* The OS must have enabled XSAVE. */
if (!(env->cr[4] & CR4_OSXSAVE_MASK)) {
raise_exception_ra(env, EXCP06_ILLOP, ra);
}
/* The operand must be 64 byte aligned. */
if (ptr & 63) {
raise_exception_ra(env, EXCP0D_GPF, ra);
}
/* Never save anything not enabled by XCR0. */
rfbm &= env->xcr0;
opt &= rfbm;
if (opt & XSTATE_FP_MASK) {
do_xsave_fpu(env, ptr, ra);
}
if (rfbm & XSTATE_SSE_MASK) {
/* Note that saving MXCSR is not suppressed by XSAVEOPT. */
do_xsave_mxcsr(env, ptr, ra);
}
if (opt & XSTATE_SSE_MASK) {
do_xsave_sse(env, ptr, ra);
}
if (opt & XSTATE_BNDREGS_MASK) {
do_xsave_bndregs(env, ptr + XO(bndreg_state), ra);
}
if (opt & XSTATE_BNDCSR_MASK) {
do_xsave_bndcsr(env, ptr + XO(bndcsr_state), ra);
}
if (opt & XSTATE_PKRU_MASK) {
do_xsave_pkru(env, ptr + XO(pkru_state), ra);
}
/* Update the XSTATE_BV field. */
old_bv = cpu_ldq_data_ra(env, ptr + XO(header.xstate_bv), ra);
new_bv = (old_bv & ~rfbm) | (inuse & rfbm);
cpu_stq_data_ra(env, ptr + XO(header.xstate_bv), new_bv, ra);
}
void helper_xsave(CPUX86State *env, target_ulong ptr, uint64_t rfbm)
{
do_xsave(env, ptr, rfbm, get_xinuse(env), -1, GETPC());
}
void helper_xsaveopt(CPUX86State *env, target_ulong ptr, uint64_t rfbm)
{
uint64_t inuse = get_xinuse(env);
do_xsave(env, ptr, rfbm, inuse, inuse, GETPC());
}
static void do_xrstor_fpu(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
int i, fpuc, fpus, fptag;
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target_ulong addr;
fpuc = cpu_lduw_data_ra(env, ptr + XO(legacy.fcw), ra);
fpus = cpu_lduw_data_ra(env, ptr + XO(legacy.fsw), ra);
fptag = cpu_lduw_data_ra(env, ptr + XO(legacy.ftw), ra);
cpu_set_fpuc(env, fpuc);
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env->fpstt = (fpus >> 11) & 7;
env->fpus = fpus & ~0x3800;
fptag ^= 0xff;
for (i = 0; i < 8; i++) {
env->fptags[i] = ((fptag >> i) & 1);
}
addr = ptr + XO(legacy.fpregs);
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for (i = 0; i < 8; i++) {
floatx80 tmp = helper_fldt(env, addr, ra);
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ST(i) = tmp;
addr += 16;
}
}
static void do_xrstor_mxcsr(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
cpu_set_mxcsr(env, cpu_ldl_data_ra(env, ptr + XO(legacy.mxcsr), ra));
}
static void do_xrstor_sse(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
int i, nb_xmm_regs;
target_ulong addr;
if (env->hflags & HF_CS64_MASK) {
nb_xmm_regs = 16;
} else {
nb_xmm_regs = 8;
}
addr = ptr + XO(legacy.xmm_regs);
for (i = 0; i < nb_xmm_regs; i++) {
env->xmm_regs[i].ZMM_Q(0) = cpu_ldq_data_ra(env, addr, ra);
env->xmm_regs[i].ZMM_Q(1) = cpu_ldq_data_ra(env, addr + 8, ra);
addr += 16;
}
}
static void do_xrstor_bndregs(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
target_ulong addr = ptr + offsetof(XSaveBNDREG, bnd_regs);
int i;
for (i = 0; i < 4; i++, addr += 16) {
env->bnd_regs[i].lb = cpu_ldq_data_ra(env, addr, ra);
env->bnd_regs[i].ub = cpu_ldq_data_ra(env, addr + 8, ra);
}
}
static void do_xrstor_bndcsr(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
/* FIXME: Extend highest implemented bit of linear address. */
env->bndcs_regs.cfgu
= cpu_ldq_data_ra(env, ptr + offsetof(XSaveBNDCSR, bndcsr.cfgu), ra);
env->bndcs_regs.sts
= cpu_ldq_data_ra(env, ptr + offsetof(XSaveBNDCSR, bndcsr.sts), ra);
}
static void do_xrstor_pkru(CPUX86State *env, target_ulong ptr, uintptr_t ra)
{
env->pkru = cpu_ldq_data_ra(env, ptr, ra);
}
void helper_fxrstor(CPUX86State *env, target_ulong ptr)
{
uintptr_t ra = GETPC();
/* The operand must be 16 byte aligned */
if (ptr & 0xf) {
raise_exception_ra(env, EXCP0D_GPF, ra);
}
do_xrstor_fpu(env, ptr, ra);
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if (env->cr[4] & CR4_OSFXSR_MASK) {
do_xrstor_mxcsr(env, ptr, ra);
/* Fast FXRSTOR leaves out the XMM registers */
2015-08-21 07:04:50 +00:00
if (!(env->efer & MSR_EFER_FFXSR)
|| (env->hflags & HF_CPL_MASK)
|| !(env->hflags & HF_LMA_MASK)) {
do_xrstor_sse(env, ptr, ra);
2015-08-21 07:04:50 +00:00
}
}
}
#if defined(CONFIG_USER_ONLY)
void cpu_x86_fxsave(CPUX86State *env, target_ulong ptr)
{
helper_fxsave(env, ptr);
}
void cpu_x86_fxrstor(CPUX86State *env, target_ulong ptr)
{
helper_fxrstor(env, ptr);
}
#endif
void helper_xrstor(CPUX86State *env, target_ulong ptr, uint64_t rfbm)
{
uintptr_t ra = GETPC();
uint64_t xstate_bv, xcomp_bv, reserve0;
rfbm &= env->xcr0;
/* The OS must have enabled XSAVE. */
if (!(env->cr[4] & CR4_OSXSAVE_MASK)) {
raise_exception_ra(env, EXCP06_ILLOP, ra);
}
/* The operand must be 64 byte aligned. */
if (ptr & 63) {
raise_exception_ra(env, EXCP0D_GPF, ra);
}
xstate_bv = cpu_ldq_data_ra(env, ptr + XO(header.xstate_bv), ra);
if ((int64_t)xstate_bv < 0) {
/* FIXME: Compact form. */
raise_exception_ra(env, EXCP0D_GPF, ra);
}
/* Standard form. */
/* The XSTATE_BV field must not set bits not present in XCR0. */
if (xstate_bv & ~env->xcr0) {
raise_exception_ra(env, EXCP0D_GPF, ra);
}
/* The XCOMP_BV field must be zero. Note that, as of the April 2016
revision, the description of the XSAVE Header (Vol 1, Sec 13.4.2)
describes only XCOMP_BV, but the description of the standard form
of XRSTOR (Vol 1, Sec 13.8.1) checks bytes 23:8 for zero, which
includes the next 64-bit field. */
xcomp_bv = cpu_ldq_data_ra(env, ptr + XO(header.xcomp_bv), ra);
reserve0 = cpu_ldq_data_ra(env, ptr + XO(header.reserve0), ra);
if (xcomp_bv || reserve0) {
raise_exception_ra(env, EXCP0D_GPF, ra);
}
if (rfbm & XSTATE_FP_MASK) {
if (xstate_bv & XSTATE_FP_MASK) {
do_xrstor_fpu(env, ptr, ra);
} else {
helper_fninit(env);
memset(env->fpregs, 0, sizeof(env->fpregs));
}
}
if (rfbm & XSTATE_SSE_MASK) {
/* Note that the standard form of XRSTOR loads MXCSR from memory
whether or not the XSTATE_BV bit is set. */
do_xrstor_mxcsr(env, ptr, ra);
if (xstate_bv & XSTATE_SSE_MASK) {
do_xrstor_sse(env, ptr, ra);
} else {
/* ??? When AVX is implemented, we may have to be more
selective in the clearing. */
memset(env->xmm_regs, 0, sizeof(env->xmm_regs));
}
}
if (rfbm & XSTATE_BNDREGS_MASK) {
if (xstate_bv & XSTATE_BNDREGS_MASK) {
do_xrstor_bndregs(env, ptr + XO(bndreg_state), ra);
env->hflags |= HF_MPX_IU_MASK;
} else {
memset(env->bnd_regs, 0, sizeof(env->bnd_regs));
env->hflags &= ~HF_MPX_IU_MASK;
}
}
if (rfbm & XSTATE_BNDCSR_MASK) {
if (xstate_bv & XSTATE_BNDCSR_MASK) {
do_xrstor_bndcsr(env, ptr + XO(bndcsr_state), ra);
} else {
memset(&env->bndcs_regs, 0, sizeof(env->bndcs_regs));
}
cpu_sync_bndcs_hflags(env);
}
if (rfbm & XSTATE_PKRU_MASK) {
uint64_t old_pkru = env->pkru;
if (xstate_bv & XSTATE_PKRU_MASK) {
do_xrstor_pkru(env, ptr + XO(pkru_state), ra);
} else {
env->pkru = 0;
}
if (env->pkru != old_pkru) {
CPUState *cs = env_cpu(env);
tlb_flush(cs);
}
}
}
#undef XO
uint64_t helper_xgetbv(CPUX86State *env, uint32_t ecx)
{
/* The OS must have enabled XSAVE. */
if (!(env->cr[4] & CR4_OSXSAVE_MASK)) {
raise_exception_ra(env, EXCP06_ILLOP, GETPC());
}
switch (ecx) {
case 0:
return env->xcr0;
case 1:
if (env->features[FEAT_XSAVE] & CPUID_XSAVE_XGETBV1) {
return env->xcr0 & get_xinuse(env);
}
break;
}
raise_exception_ra(env, EXCP0D_GPF, GETPC());
}
void helper_xsetbv(CPUX86State *env, uint32_t ecx, uint64_t mask)
{
uint32_t dummy, ena_lo, ena_hi;
uint64_t ena;
/* The OS must have enabled XSAVE. */
if (!(env->cr[4] & CR4_OSXSAVE_MASK)) {
raise_exception_ra(env, EXCP06_ILLOP, GETPC());
}
/* Only XCR0 is defined at present; the FPU may not be disabled. */
if (ecx != 0 || (mask & XSTATE_FP_MASK) == 0) {
goto do_gpf;
}
/* Disallow enabling unimplemented features. */
cpu_x86_cpuid(env, 0x0d, 0, &ena_lo, &dummy, &dummy, &ena_hi);
ena = ((uint64_t)ena_hi << 32) | ena_lo;
if (mask & ~ena) {
goto do_gpf;
}
/* Disallow enabling only half of MPX. */
if ((mask ^ (mask * (XSTATE_BNDCSR_MASK / XSTATE_BNDREGS_MASK)))
& XSTATE_BNDCSR_MASK) {
goto do_gpf;
}
env->xcr0 = mask;
cpu_sync_bndcs_hflags(env);
return;
do_gpf:
raise_exception_ra(env, EXCP0D_GPF, GETPC());
}
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/* MMX/SSE */
/* XXX: optimize by storing fptt and fptags in the static cpu state */
#define SSE_DAZ 0x0040
#define SSE_RC_MASK 0x6000
#define SSE_RC_NEAR 0x0000
#define SSE_RC_DOWN 0x2000
#define SSE_RC_UP 0x4000
#define SSE_RC_CHOP 0x6000
#define SSE_FZ 0x8000
void update_mxcsr_status(CPUX86State *env)
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{
uint32_t mxcsr = env->mxcsr;
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int rnd_type;
/* set rounding mode */
switch (mxcsr & SSE_RC_MASK) {
default:
case SSE_RC_NEAR:
rnd_type = float_round_nearest_even;
break;
case SSE_RC_DOWN:
rnd_type = float_round_down;
break;
case SSE_RC_UP:
rnd_type = float_round_up;
break;
case SSE_RC_CHOP:
rnd_type = float_round_to_zero;
break;
}
set_float_rounding_mode(rnd_type, &env->sse_status);
/* set denormals are zero */
set_flush_inputs_to_zero((mxcsr & SSE_DAZ) ? 1 : 0, &env->sse_status);
/* set flush to zero */
set_flush_to_zero((mxcsr & SSE_FZ) ? 1 : 0, &env->fp_status);
}
void helper_ldmxcsr(CPUX86State *env, uint32_t val)
{
cpu_set_mxcsr(env, val);
}
void helper_enter_mmx(CPUX86State *env)
{
env->fpstt = 0;
*(uint32_t *)(env->fptags) = 0;
*(uint32_t *)(env->fptags + 4) = 0;
}
void helper_emms(CPUX86State *env)
{
/* set to empty state */
*(uint32_t *)(env->fptags) = 0x01010101;
*(uint32_t *)(env->fptags + 4) = 0x01010101;
}
/* XXX: suppress */
void helper_movq(CPUX86State *env, void *d, void *s)
{
*(uint64_t *)d = *(uint64_t *)s;
}
#define SHIFT 0
#include "ops_sse.h"
#define SHIFT 1
#include "ops_sse.h"