We already require gcc 4.1 or newer (for the atomic
support), so the fallback codepaths for older gcc
versions than that are now dead code and we can
just delete them.
NB: clang reports itself as gcc 4.2 (regardless of
clang version), so clang won't be using the fallbacks
either.
Backports commit fa54abb8c298f892639ffc4bc2f61448ac3be4a1 from qemu
The C store helper functions take the address argument as a
target_ulong type; if this is 32 bit but the host is 64 bit
then the SPARC calling convention requires that the caller
must zero extend the value. We weren't doing this, which
meant we could pass values to the caller with high bits set
and QEMU would crash if it was compiled with optimizations.
In particular, the i386 BIOS would not start.
Backports commit 5c32be5baf41aec4f4675d2bf24f9948756abf3c from qemu
The C store helper functions take the data argument as a uint8_t,
uint16_t, etc depending on the store size. The SPARC calling
convention requires that data types smaller than the register
size must be extended by the caller. We weren't doing this,
which meant that if QEMU was compiled with optimizations enabled
we could end up storing incorrect values to guest memory.
(In particular the i386 guest BIOS would crash on startup.)
Add code to the trampolines that call the store helpers to
do the zero extension as required.
Backports commit 709a340d679d95a0c6cbb9b5f654498f04345b50 from qemu
To fix the following warnings:
In file included from /users/pranith/qemu/tcg/tcg.c:255:
/users/pranith/qemu/tcg/aarch64/tcg-target.inc.c:879:24: warning: implicit conversion from enumeration type 'TCGMemOp' (aka 'enum TCGMemOp') to different enumeration type 'TCGType' (aka 'enum TCGType')
[-Wenum-conversion]
tcg_out_cmp(s, ext, a, b, b_const);
~~~~~~~~~~~ ^~~
/users/pranith/qemu/tcg/aarch64/tcg-target.inc.c:893:36: warning: implicit conversion from enumeration type 'TCGMemOp' (aka 'enum TCGMemOp') to different enumeration type 'TCGType' (aka 'enum TCGType')
[-Wenum-conversion]
tcg_out_insn(s, 3201, CBZ, ext, a, offset);
~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
/users/pranith/qemu/tcg/aarch64/tcg-target.inc.c:389:65: note: expanded from macro 'tcg_out_insn'
glue(tcg_out_insn_,FMT)(S, glue(glue(glue(I,FMT),_),OP), ## __VA_ARGS__)
^
/users/pranith/qemu/tcg/aarch64/tcg-target.inc.c:895:37: warning: implicit conversion from enumeration type 'TCGMemOp' (aka 'enum TCGMemOp') to different enumeration type 'TCGType' (aka 'enum TCGType')
[-Wenum-conversion]
tcg_out_insn(s, 3201, CBNZ, ext, a, offset);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
/users/pranith/qemu/tcg/aarch64/tcg-target.inc.c:389:65: note: expanded from macro 'tcg_out_insn'
glue(tcg_out_insn_,FMT)(S, glue(glue(glue(I,FMT),_),OP), ## __VA_ARGS__)
^
/users/pranith/qemu/tcg/aarch64/tcg-target.inc.c:1610:27: warning: implicit conversion from enumeration type 'TCGType' (aka 'enum TCGType') to different enumeration type 'TCGMemOp' (aka 'enum TCGMemOp')
[-Wenum-conversion]
tcg_out_brcond(s, ext, a2, a0, a1, const_args[1], arg_label(args[3]));
~~~~~~~~~~~~~~ ^~~
backports commit dc1eccd661ada3b746ca4438e444993c36a0f04f from qemu
This enables the multi-threaded system emulation by default for ARMv7
and ARMv8 guests using the x86_64 TCG backend. This is because on the
guest side:
- The ARM translate.c/translate-64.c have been converted to
- use MTTCG safe atomic primitives
- emit the appropriate barrier ops
- The ARM machine has been updated to
- hold the BQL when modifying shared cross-vCPU state
- defer powerctl changes to async safe work
All the host backends support the barrier and atomic primitives but
need to provide same-or-better support for normal load/store
operations.
Backports commit ca759f9e387db87e1719911f019bc60c74be9ed8 from qemu
We know there will be cases where MTTCG won't work until additional work
is done in the front/back ends to support. It will however be useful to
be able to turn it on.
As a result MTTCG will default to off unless the combination is
supported. However the user can turn it on for the sake of testing.
Backports commit 8d4e9146b3568022ea5730d92841345d41275d66 from qemu
We'll be using the memory ordering definitions to define values for
both the host and guest. To avoid fighting with circular header
dependencies just move these types into their own minimal header.
Backports commit 20937143145b8f5a4194e5c407731ba38797864e from qemu
Particularly when andc is also available, this is two insns
shorter than using clz to compute ctz.
Backports commit 14e99210f6c6cede461a54b2e0f9b4cd55175f00 from qemu
The number of actual invocations of ctpop itself does not warrent
an opcode, but it is very helpful for POWER7 to use in generating
an expansion for ctz.
Backports commit a768e4e99247911f00c5c0267c12d4e207d5f6cc from qemu
The number of actual invocations does not warrent an opcode,
and the backends generating it. But at least we can eliminate
redundant helpers.
Backports commit 086920c2c8008f125fd38781072fa25c3ad158ea from qemu
Previously we could not have different constraints for different ISA levels,
which prevented us from eliding the matching constraint for shifts.
We do now have to make sure that the operands match for constant shifts.
We can also handle some small left shifts via lea.
Backports commit 6a5aed4bdc7078838a8098336588d56c9ce09d1d from qemu
Use a switch instead of searching a table. Share constraints between
32-bit and 64-bit, when at all possible.
Backports commit cd26449a505f808e479af4fdd539e05767e09c06 from qemu
This allows an output operand to match an input operand
only when the input operand needs a register.
Backports commit 17280ff4a5f264e01e55ae514ee6d3586f9577b2 from qemu
This will let us choose how to interpret a given constraint
depending on whether the opcode is 32- or 64-bit. Which will
let us share more constraint combinations between opcodes.
At the same time, change the interface to return the advanced
pointer instead of passing it in/out by reference.
Backports commit 069ea736b50b75fdec99c9b8cc603b97bd98419e from qemu
This will allow the target to tailor the constraints to the
auto-detected ISA extensions.
Backports commit f69d277ece43c42c7ab0144c2ff05ba740f6706b from qemu
Since we can no longer use matching constraints, this does
mean we must handle that data movement by hand.
Backports commit 752b1be94757de906b9c24ebc8f5e6aa54b96b23 from qemu
This lets us expose facilities to TCG_TARGET_HAS_* defines
directly, rather than hiding behind function calls.
Backports commit b2c98d9d392c87c9b9e975d30f79924719d9cbbe from qemu
This allows us to use this detection within the TCG_TARGET_HAS_*
macros, instead of requiring a function call into tcg-target.inc.c.
Backports commit 40b2ccb156534f5d5f1d110a6ce008d87ee10af1 from qemu
While we don't require a new opcode, it is handy to have an expander
that knows the first source is zero.
Backports commit 07cc68d52852bf47dea7c402b46ddd28248d4212 from qemu
Adds tcg_gen_extract_* and tcg_gen_sextract_* for extraction of
fixed position bitfields, much like we already have for deposit.
Backports commit 7ec8bab3deae643b1ce579c2d65a244f30708330 from qemu
tcg_out_ldst: using a generic ALIAS_PADD to avoid ifdefs
tcg_out_ld: generates LD or LW
tcg_out_st: generates SD or SW
Backports commit 32b69707df3365aadaad1d058044a7704397ec62 from qemu
tcg_out_mov: using OPC_OR as most mips assemblers do;
tcg_out_movi: extended to 64-bit immediate.
Backports commit 2294d05dab503d11664e73712c7f250fd0bf9e3b from qemu
Without the mips32r2 instructions to perform swapping, bswap is quite large,
dominating the size of each reverse-endian qemu_ld/qemu_st operation.
Create two subroutines in the prologue block. The subroutines require extra
reserved registers (TCG_TMP[2, 3]). Using these within qemu_ld means that
we need not place additional restrictions on the qemu_ld outputs.
Backports commit 7f54eaa3b78d71cb57e45a719980f9b5ff06d21c from qemu
Bulk patch adding 64-bit opcodes into tcg_out_op. Note that
mips64 is as yet neither complete nor enabled.
Backports commit 0119b1927d531f3fac22b9b4da01dafc23644973 from qemu
Since the mips manual tables are in octal, reorg all of the opcodes
into that format for clarity. Note that the 64-bit opcodes are as
yet unused.
Backports commit 57a701fc2b34902310d4dbd1411088055616938a from qemu
Without the mips32r2 instructions to perform swapping, bswap is quite large,
dominating the size of each reverse-endian qemu_ld/qemu_st operation.
Create a subroutine in the prologue block. The subroutine requires extra
reserved registers (TCG_TMP[2, 3]). Using these within qemu_ld means that
we need not place additional restrictions on the qemu_ld outputs.
Backports commit bb08afe9f0aee1a3f5c23508e2511b882ca31e1b from qemu
Update helper to set the throwing location in case of div-by-0.
Cleanup divX.w and add quad word variants of divX.l.
Backports commit 0ccb9c1d8128a020720d5c6abf99a470742a1b94 from qemu
We can't use LOAD AND TEST for unsigned data and then expect to
extract the result with ADD LOGICAL WITH CARRY. Fall through to
using COMPARE LOGICAL IMMEDIATE instead.
Backports commit 65839b56b9a740e6b898b5d81afc160502bd2935 from qemu
There were some patterns, like 0x0000_ffff_ffff_00ff, for which we
would select to begin a multi-insn sequence with MOVN, but would
fail to set the 0x0000 lane back from 0xffff.
Backports commit 50b468d42107a2c646b1c566ed17d9ec362c51c4 from qemu
When al == xzr, we cannot use addi/subi because that encodes xsp.
Force a zero into the temp register for that (rare) case.
Backports commit 028fbea47713f909d6ea761a457779a82b276247 from qemu
The version of tcg_gen_ld8s_i64 for 32-bit systems does a load into
the low part of the return value - then attempts a sign extension into
the high part, but wrongly sets the high part to a sign extension of
itself rather than of the low part. This results in TCG internal
errors from the use of the uninitialized high part (in some GCC tests
of AArch64 NEON shift intrinsics, in particular). This patch corrects
the sign-extension logic, making it match other functions such as
tcg_gen_ld16s_i64.
Backports commit 3ff91d7e85176f8b4b131163d7fd801757a2c949 from qemu
The typedefs we use for the TCGv_i32, TCGv_i64 and TCGv_ptr
types are somewhat confusing, because we define them as
pointers to structs, but the structs themselves are never
defined. Explain in the comments a bit more clearly why
this is OK and what is going on under the hood.
Backports commit a40d4701bc9f6e6a3bbfb7b4fbe756a5b72b5df1 from qemu
This multiply has one signed input and one unsigned input,
producing the full double-width result.
Backports commit 5087abfb7dfd1d368ae6939420057036b4d8e509 from qemu
softmmu requires more functions to be thread-safe, because translation
blocks can be invalidated from e.g. notdirty callbacks. Probably the
same holds for user-mode emulation, it's just that no one has ever
tried to produce a coherent locking there.
This patch will guide the introduction of more tb_lock and tb_unlock
calls for system emulation.
Note that after this patch some (most) of the mentioned functions are
still called outside tb_lock/tb_unlock. The next one will rectify this.
Backports commit 7d7500d99895f888f97397ef32bb536bb0df3b74 from qemu
Allow qemu to build on 32-bit hosts without 64-bit atomic ops.
Even if we only allow 32-bit hosts to multi-thread emulate 32-bit
guests, we still need some way to handle the 32-bit guest using a
64-bit atomic operation. Do so by dropping back to single-step.
Backports commit df79b996a7b21c6ea7847f7927a2e1a294b86c72 from qemu
Force the use of cmpxchg16b on x86_64.
Wikipedia suggests that only very old AMD64 (circa 2004) did not have
this instruction. Further, it's required by Windows 8 so no new cpus
will ever omit it.
If we truely care about these, then we could check this at startup time
and then avoid executing paths that use it.
Backports commit 7ebee43ee3e2fcd7b5063058b7ef74bc43216733 from qemu
Add all of cmpxchg, op_fetch, fetch_op, and xchg.
Handle both endian-ness, and sizes up to 8.
Handle expanding non-atomically, when emulating in serial.
Backports commit c482cb117cc418115ca9c6d21a7a2315414c0a40 from qemu
This comes from free from unifying tcg_reg_alloc_mov and
tcg_reg_alloc_movi's handling of TEMP_VAL_CONST. It triggers
often on moves to cc_dst, such as the following translation
of "sub $0x3c,%esp":
before: after:
subl $0x3c,%ebp subl $0x3c,%ebp
movl %ebp,0x10(%r14) movl %ebp,0x10(%r14)
movl $0x3c,%ebx movl $0x3c,0x2c(%r14)
movl %ebx,0x2c(%r14)
Backports commit 0fe4fca4e1a5e06a270127dd80bb753d4dda61c6 from qemu
This is to appease sanitizer builds which complain that:
"error: control reaches end of non-void function"
Backports commit 550276ae0a88851edda2cb7fcdd64256dbb8e314 from qemu
TARGET_PAGE_MASK, as defined, has type "int". We need to extend
that to the proper target width before oring in an "unsigned".
Backports commit ebb90a005da67147245cd38fb04a965a87a961b7 from qemu
This commit optimizes fence instructions. Two optimizations are
currently implemented: (1) unnecessary duplicate fence instructions,
and (2) merging weaker fences into a stronger fence.
[rth: Merge tcg_optimize_mb back into tcg_optimize, so that we only
loop over the opcode stream once. Merge "unrelated" weaker barriers
into one stronger barrier.]
Backports commit 34f939218ce78163171addd63750e1e0300376ab from qemu
Generate a 'lock orl $0,0(%esp)' instruction for ordering instead of
mfence which has similar ordering semantics.
Backports commit a7d00d4effb58889ac6df64f98ac50c9d1594149 from qemu
This commit introduces the TCGOpcode for memory barrier instruction.
This opcode takes an argument which is the type of memory barrier
which should be generated.
Backports commit f65e19bc2c9e8358e634d309606144ac2a3c2936 from qemu
Previously we allowed fully unaligned operations, but not operations
that are aligned but with less alignment than the operation size.
In addition, arm32, ia64, mips, and sparc had been omitted from the
previous overalignment patch, which would have led to that alignment
being enforced.
Backports commit 85aa80813dd9f5c1f581c743e45678a3bee220f8 from qemu
Unused function declarations were found using a simple gcc plugin and
manually verified by grepping the sources.
Backports commit d4b84d564ee3eb7a58e4585d671fb3c220b6c3b9 from qemu
Rather than rely on recursion during the middle of register allocation,
lower indirect registers to loads and stores off the indirect base into
plain temps.
For an x86_64 host, with sufficient registers, this results in identical
code, modulo the actual register assignments.
For an i686 host, with insufficient registers, this means that temps can
be (temporarily) spilled to the stack in order to satisfy an allocation.
This as opposed to the possibility of not being able to spill, to allocate
a register for the indirect base, in order to perform a spill.
Backports commit 5a18407f55ade924aa6397c9a043a9ffd59645fe from qemu
We only need two bits per temporary. Fold the two bytes into one,
and reduce the memory and cachelines required during compilation.
Backports commit c70fbf0a9938baf3b4f843355a77c17a7e945b98 from qemu
Reduce the size of other bitfields to make room.
This reduces the cache footprint of compilation.
Backports commit bee158cb4dde35c41632a3a129c869f14a32f8f0 from qemu
Instead of using -1 as end of chain, use 0, and link through the 0
entry as a fully circular double-linked list.
Backports commit dcb8e75870e2de199db853697f8839cb603beefe from qemu
This reduces both memory usage and per-insn cacheline usage
during code generation.
Backports commit a1b3c48d2b23d6eaeb4529d3e1183d2648731bf8 from qemu
Assertions help both Coverity and the clang static analyzer avoid
false positives, but on the other hand both are confused when
the condition is compiled as (void)(x != FOO). Always expand
assertion macros when using Coverity or clang, through a new
QEMU_STATIC_ANALYSIS preprocessor symbol.
This fixes a couple false positives in TCG.
Backports commit 8bff06a0bbf257a2083223534c1607bf87d913e6 from qemu
Knowing the value of %asi at translation time means that we
can handle the common settings without a function call.
The steady state appears to be %asi == ASI_P, so that sparcv9
code can use offset forms of lda/sta. The %asi register gets
pushed and popped on entry to certain functions, but it rarely
takes on values other than ASI_P or ASI_AIUP. Therefore we're
unlikely to be expanding the set of TBs created.
Backports commit a6d567e523ed7e928861f3caa5d49368af3f330d from qemu
The global is only ever read for one insn; we can just as well
use a load from env instead and generate the same code. This
also allows us to indicate the the associated helpers do not
touch TCG globals.
Backports commit e86ceb0d652baa5738e05a59ee0e7989dafbeaa1 from qemu
These use guard symbols like TCG_TARGET_$target.
scripts/clean-header-guards.pl doesn't like them because they don't
match their file name (they should, to make guard collisions less
likely).
Clean them up: use guard symbol $target_TCG_TARGET_H for
tcg/$target/tcg-target.h.
Backports commit 14e54f8ecfe9c5e17348f456781344737ed10b3b from qemu
Some architectures (e.g. ARMv8) need the address which is aligned
to a size more than the size of the memory access.
To support such check it's enough the current costless alignment
check implementation in QEMU, but we need to support
an alignment size specifying.
Backports commit 1f00b27f17518a1bcb4cedca49eaec96a4d560bd from qemu
While we can store constants via constrants on INDEX_op_st_i32 et al,
we weren't able to spill constants to backing store.
Add a new backend interface, tcg_out_sti, which may store the constant
(and is allowed to fail). Rearrange the temp_* helpers so that we only
attempt to directly store a constant when the temp is becoming dead/free.
Backports commit 59d7c14eeff8d2ad7f61aed86ce5a176113bc153 from qemu
Information is tracked inside the TCGContext structure, and later used
by tracing events with the 'tcg' and 'vcpu' properties.
The 'cpu' field is used to check tracing of translation-time
events ("*_trans"). The 'tcg_env' field is used to pass it to
execution-time events ("*_exec").
Backports commit 7c2550432abe62f53e6df878ceba6ceaf71f0e7e from qemu
exec-all.h contains TCG-specific definitions. It is not needed outside
TCG-specific files such as translate.c, exec.c or *helper.c.
One generic function had snuck into include/exec/exec-all.h; move it to
include/qom/cpu.h.
Backports commit 63c915526d6a54a95919ebece83fa9ca631b2508 from qemu
TCG backends do not need most of exec-all.h; extract what they actually
need to a separate file or move it directly to tcg.h. The next patch
will stop including exec-all.h from everywhere.
Backports commit 00f6da6a1a5d1ce085334eccbb50ec899ceed513 from qemu
The value returned from tcg_qemu_tb_exec() is the value passed to the
corresponding tcg_gen_exit_tb() at translation time of the last TB
attempted to execute. It is a little confusing to store it in a variable
named 'next_tb'. In fact, it is a combination of 4-byte aligned pointer
and additional information in its two least significant bits. Break it
down right away into two variables named 'last_tb' and 'tb_exit' which
are a pointer to the last TB attempted to execute and the TB exit
reason, correspondingly. This simplifies the code and improves its
readability.
Correct a misleading documentation comment for tcg_qemu_tb_exec() and
fix logging in cpu_tb_exec(). Also rename a misleading 'next_tb' in
another couple of places.
Backports commit 819af24b9c1e95e6576f1cefd32f4d6bf56dfa56 from qemu
In user mode, there's only a static address translation, TBs are always
invalidated properly and direct jumps are reset when mapping change.
Thus the destination address is always valid for direct jumps and
there's no need to restrict it to the pages the TB resides in.
Backports commit 90aa39a1cc4837360889f0e033ca25cc82100308 from qemu
We don't take care of direct jumps when address mapping changes. Thus we
must be sure to generate direct jumps so that they always keep valid
even if address mapping changes. Luckily, we can only allow to execute a
TB if it was generated from the pages which match with current mapping.
Document tcg_gen_goto_tb() declaration and note the reason for
destination PC limitations.
Some targets with variable length instructions allow TB to straddle a
page boundary. However, we make sure that both of TB pages match the
current address mapping when looking up TBs. So it is safe to do direct
jumps into the both pages. Correct the checks for some of those targets.
Given that, we can safely patch a TB which spans two pages. Remove the
unnecessary check in cpu_exec() and allow such TBs to be patched.
Backports commit 5b053a4a28278bca606eeff7d1c0730df1b047e9 from qemu
Briefly describe in a comment how direct block chaining is done. It
should help in understanding of the following data fields.
Rename some fields in TranslationBlock and TCGContext structures to
better reflect their purpose (dropping excessive 'tb_' prefix in
TranslationBlock but keeping it in TCGContext):
tb_next_offset => jmp_reset_offset
tb_jmp_offset => jmp_insn_offset
tb_next => jmp_target_addr
jmp_next => jmp_list_next
jmp_first => jmp_list_first
Avoid using a magic constant as an invalid offset which is used to
indicate that there's no n-th jump generated.
Backports commit f309101c26b59641fc1aa8fb2a98a5441cdaea03 from qemu
Ensure direct jump patching in MIPS is atomic by using
atomic_read()/atomic_set() for code patching.
Backports commit c82460a560176ef69c2f0662bd280612e274db96 from qemu
Ensure direct jump patching in SPARC is atomic by using
atomic_read()/atomic_set() for code patching.
Backports commit 84f79fb7c6e857edc807e4a251338243ce0cbac3 from qemu
Ensure direct jump patching in AArch64 is atomic by using
atomic_read()/atomic_set() for code patching.
Backports commit 9e269112953be4d670cb0d25042bd6546fcf3e45 from qemu
Ensure direct jump patching in ARM is atomic by using
atomic_read()/atomic_set() for code patching.
Backports commit 7d14e0e2d661479985197203589c38840e1066df from qemu
Ensure direct jump patching in s390 is atomic by:
* naturally aligning a location of direct jump address;
* using atomic_read()/atomic_set() for code patching.
Backports commit ed3d51ecd7fe248d3959e469d53890ac9ffe0cd2 from qemu
Ensure direct jump patching in i386 is atomic by:
* naturally aligning a location of direct jump address;
* using atomic_read()/atomic_set() for code patching.
Backports commit 0d07abf05e98903c7faf204a9a90f7d45b7554dc from qemu
Add tcg_set_insn_param as a mechanism to modify an insn
parameter after emiting the insn. This is useful for icount
and also for embedding fault information for a specific insn.
Backports commit 1d41478fd428e01f057d3248292e4cdcdb048523 from qemu
The TCG code is quite performance sensitive, but at the same time can
also be quite tricky. That is why asserts that can be enabled with the
--enable-debug-tcg configure option.
This used to work the following way:
| #include "config.h"
|
| ...
|
| #if !defined(CONFIG_DEBUG_TCG) && !defined(NDEBUG)
| /* define it to suppress various consistency checks (faster) */
| #define NDEBUG
| #endif
|
| ...
|
| #include <assert.h>
Since commit 757e725b (tcg: Clean up includes) "config.h" as been
replaced by "qemu/osdep.h" which itself includes <assert.h>. As a
consequence the assertions are always enabled, even when using
--disable-debug-tcg, causing a performance regression, especially on
targets with many registers. For instance on qemu-system-ppc the
speed difference is about 15%.
tcg_debug_assert is controlled directly by CONFIG_DEBUG_TCG and already
uses in some places. This patch replaces all the calls to assert into
calss to tcg_debug_assert.
Backports commit eabb7b91b36b202b4dac2df2d59d698e3aff197a from qemu
The MIPS TCG backend is the only one to have
tcg_target_reg_alloc_order[] elements of type TCGReg rather than int.
This resulted in commit 91478cefaaf2 ("tcg: Allocate indirect_base
temporaries in a different order") breaking the build on MIPS since the
type differed from indirect_reg_alloc_order[]:
tcg/tcg.c:1725:44: error: pointer type mismatch in conditional expression [-Werror]
order = rev ? indirect_reg_alloc_order : tcg_target_reg_alloc_order;
^
Make it an array of ints to fix the build and match other architectures.
Backports commit 2dc7553d0c0a3915c649e1a91b0f0be70b4674b3 from qemu
qemu-log: dfilter-ise exec, out_asm, op and opt_op
This ensures the code generation debug code will honour -dfilter if set.
For the "exec" tracing I've added a new inline macro for efficiency's
sake.
Backports commit d977e1c2dbc9e63454b2000f91954d02543bf43b from qemu
My later debugging patches need access to the origin PC which is held in
the TranslationBlock structure. Pass down the whole structure as it also
holds the information about the code start point.
Backports commit 5bd2ec3d7b47b2252745882795d79aef36380fb7 from qemu
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)
Backports commit f348b6d1a53e5271cf1c9f9acc4646b4b98c1771 from qemu
The target-dependant type TCGv must be defined in "tcg/tcg.h" before
including the tracing helper wrappers in "tcg/tcg-op.h".
It also makes more sense to define it here, where other TCG types are
defined too.
Backports commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 from qemu
Adds the 'TCGv_env' type for pointers to 'CPUArchState' objects. The
tracing infrastructure later needs to differentiate between regular
pointers and pointers to vCPUs.
Also changes all targets to use the new 'TCGv_env' type instead of the
generic 'TCGv_ptr'. As of now, the change is merely cosmetic ('TCGv_env'
translates into 'TCGv_ptr'), but that could change in the future to
enforce the difference.
Note that a 'TCGv_env' type (for 'CPUState') is not added, since all
helpers currently receive the architecture-specific
pointer ('CPUArchState').
Backports commit 1bcea73e13b2b059d0cb3301aeaca43e5656ef57 from qemu
Commit 757e725b58c57d added a number of #include "qemu/osdep.h"
files to the tcg-target.c files (as they were named at the time).
These are unnecessary because these files are not standalone C
files, and the tcg/tcg.c file which includes them will have
already included osdep.h on their behalf. Remove the unneeded
include directives.
Backports commit c3b7f66800fbf9f47fddbcf2e2cd30ea932e0aae from qemu
Rename the per-architecture tcg-target.c files to tcg-target.inc.c.
This makes it clearer that they are not intended to be standalone
C files, but are instead #included into another source file.
Backports commit ce151109813e2770fd3cee2f37bfa2cdd01a12b9 from qemu
Since we've not got liveness analysis for indirect bases,
placing them at the end of the call-saved registers makes
it more likely that it'll stay live.
Backports commit 91478cefaaf2fa678e56df8635b34957f4d5d565 from qemu
That is, global_mem registers whose base is another global_mem
register, rather than a fixed register.
Backports commit b3915dbbdcdb2e04753f3d34a1b0865eea005069 from qemu
A previous patch patch changed the type of REG from int
to enum TCGReg, which provokes the following bug in clang:
https://llvm.org/bugs/show_bug.cgi?id=16154
Backports commit 869938ae2a284fe730cb6f807ea0f9e324e0f87c from qemu
All references to cpu_T are done with a constant index. It aids
readability to decompose the array into two scalar variables.
Backports commit 1d1cc4d0f481b2939c7e9f6606e571b2fc81971a from qemu
Having segs[].base as a register significantly improves code
generation for real and protected modes, particularly for TBs
that have multiple memory references where the segment base
can be held in a hard register through the TB.
Backports commit 3558f8055f37a34762b7a2a0f02687e6eeab893d from qemu
A subsequent patch patch will change the type of REG from int
to enum TCGReg, which provokes the following bug in clang:
https://llvm.org/bugs/show_bug.cgi?id=16154
Backports commit c8074023204e8e8a213399961ab56e2814aa6116 from qemu
In particular, make sure the memory is memset before use.
Continues the increased use of TCGTemp pointers instead of
integer indices where appropriate.
Backports commit 7ca4b752feaab647b0c1a147bd3815fcdb479a59 from qemu
Undo the workaround at b17a6d3390f87620735f7efb03bb1c96682ff449.
If there are lots of memory operations in a TB, the slow path code
can exceed the highwater reservation. Add a check within the loop.
Backports commit 23dceda62a3643f734b7aa474fa6052593ae1a70 from qemu
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Backports commit 757e725b58c57d3ebb66a31fd2210df977a12154 from qemu
A simple typo in the variable to use when comparing vs the highwater mark.
Reports are that qemu can in fact segfault occasionally due to this mistake.
Backports commit 644da9b39e477caa80bab69d2847dfcb468f0d33 from qemu
Extend MIPS movcond implementation to support the SELNEZ/SELEQZ
instructions introduced in MIPS r6 (where MOVN/MOVZ have been removed).
Whereas the "MOVN/MOVZ rd, rs, rt" instructions have the following
semantics:
rd = [!]rt ? rs : rd
The "SELNEZ/SELEQZ rd, rs, rt" instructions are slightly different:
rd = [!]rt ? rs : 0
First we ensure that if one of the movcond input values is zero that it
comes last (we can swap the input arguments if we invert the condition).
This is so that it can exactly match one of the SELNEZ/SELEQZ
instructions and avoid the need to emit the other one.
Otherwise we emit the opposite instruction first into a temporary
register, and OR that into the result:
SELNEZ/SELEQZ TMP1, v2, c1
SELEQZ/SELNEZ ret, v1, c1
OR ret, ret, TMP1
Which does the following:
ret = cond ? v1 : v2
Backports commit 137d63902faf4960081856db9242cbaf234a23af from qemu
MIPSr6 adds several new integer multiply, divide, and modulo
instructions, and removes several pre-r6 encodings, along with the HI/LO
registers which were the implicit operands of some of those
instructions. Update TCG to use the new instructions when built for r6.
The new instructions actually map much more directly to the TCG ops, as
they only provide a single 32-bit half of the result and in a normal
general purpose register instead of HI or LO.
The mulu2_i32 and muls2_i32 operations are no longer appropriate for r6,
so they are removed from the TCG opcode table. This is because they
would need to emit two separate host instructions anyway (for the high
and low half of the result), which TCG can arrange automatically for us
in the absense of mulu2_i32/muls2_i32 by splitting it into mul_i32 and
mul*h_i32 TCG ops.
Backports commit bc6d0c22b09a72897d9db4482076f89e7de97400 from qemu
MIPSr6 encodes JR as JALR with zero as the link register, and the pre-r6
JR encoding is removed. Update TCG to use the new encoding when built
for r6.
We still use the old encoding for pre-r6, so as not to confuse return
prediction stack hardware which may detect only particular encodings of
the return instruction.
Backports commit 6e0d096989be52c2b945fc83a9bd15d887bbdb47 from qemu
Add definition use_mips32r6_instructions to the MIPS TCG backend which
is constant 1 when built for MIPS release 6. This will be used to decide
between pre-R6 and R6 instruction encodings.
Backports commit ce14bd4d469f3a14f6cbfceb6360aee066a60d72 from qemu
We already have a TLADDR_ARGS definition, so rearrange the order
slightly and use it in the definition of insn_start, instead of
having an #ifdef.
Backports commit c0e40dbdcc291c85faa289a53be60b7b1b7c7598 from qemu
Restrict the size of code_gen_buffer to 2GB on ppc64, which
lets us assert that everything is reachable with addis+addi
from tb_ret_addr. This lets us use a max of 4 insns for goto_tb
instead of 7.
Emit the indirect branch portion of goto_tb up front, which
means we only have to update two insns to update any link.
With a 64-bit store, we can update the link atomically, which
may be required in future.
Backports commit 5bfd75a35c11dd3aa61c73d0d2cd88137c31519c from qemu
Changing the prologue to the beginning of the code_gen_buffer
changes the direction of the "return" branch. Need to change
the logic to match.
Backports commit 70f897bdc4ce4101ec008317d43090f532bfb07d from qemu
We currently pre-compute an worst case code size for any TB, which
works out to be 122kB. Since the average TB size is near 1kB, this
wastes quite a lot of storage.
Instead, check for overflow in between generating code for each opcode.
The overhead of the check isn't measurable and wastage is minimized.
Backports commit b125f9dc7bd68cd4c57189db4da83b0620b28a72 from qemu
By putting the prologue at the end, we risk overwriting the
prologue should our estimate of maximum TB size. Given the
two different placements of the call to tcg_prologue_init,
move the high water mark computation into tcg_prologue_init.
Backports commit 8163b74938d8b7d12e70597c4553dd0dc49443d5 from qemu
It is no longer used, so tidy up everything reached by it.
This includes the gen_opc_* arrays, the search_pc parameter
and the inline gen_intermediate_code_internal functions.
Backports commit 4e5e1215156662b2b153255c49d4640d82c5568b from qemu
The gen_opc_* arrays are already redundant with the data stored in
the insn_start arguments. Transition restore_state_to_opc to use
data from the latter.
Backports commit bad729e272387de7dbfa3ec4319036552fc6c107 from qemu
Since jump_pc[1] is always npc + 4, we can infer after incrementing
that jump_pc[1] == pc + 4. Because of that, we can encode the branch
destination into a single word, and store that in npc.
Backports commit 6c42444f9a53b6af39d46008cb9f650b11e96cb9 from qemu
Instead of computing mem_index and s_bits in both tcg_out_qemu_ld and
tcg_out_qemu_st function and passing them to tcg_out_tlb_load, directly
pass oi to the tcg_out_tlb_load function and compute mem_index and
s_bits there.
Backports commit 81dfaf1a8f7f95259801da9732472f879023ef77 from qemu
tcg_op_defs (and the _max) are both needed by the TCI disassembler. For
multi-arch, tcg.c will be multiple-compiled (arch-obj) with its symbols
hidden from common code. So split the definition off to new file,
tcg-common.c which will remain a regular obj-y for use by both the TCI
disas as well as the multiple tcg.c's.
Backports commit 7d8f787d9d261d6880b69e35ed682241e3f9242f from qemu
This patch introduces several helpers to pass return address
which points to the TB. Correct return address allows correct
restoring of the guest PC and icount. These functions should be used when
helpers embedded into TB invoke memory operations.
Backports commit 282dffc8a4bfe8724548cabb8a26698bde0a6e18 from qemu
Softmmu unaligned load/stores currently goes through through the slow
path for two reasons:
- to support unaligned access on host with strict alignement
- to correctly handle accesses crossing pages
x86 is only concerned by the second reason. Unaligned accesses are
avoided by compilers, but are not uncommon. We therefore would like
to see them going through the fast path, if they don't cross pages.
For that we can use the fact that two adjacent TLB entries can't contain
the same page. Therefore accessing the TLB entry corresponding to the
first byte, but comparing its content to page address of the last byte
ensures that we don't cross pages. We can do this check without adding
more instructions in the TLB code (but increasing its length by one
byte) by using the LEA instruction to combine the existing move with the
size addition.
On an x86-64 host, this gives a 3% boot time improvement for a powerpc
guest and 4% for an x86-64 guest.
Backports commit 8cc580f6a0d8c0e2f590c1472cf5cd8e51761760 from qemu
The MIPS TCG backend implements qemu_ld with 64-bit targets using the v0
register (base) as a temporary to load the upper half of the QEMU TLB
comparator (see line 5 below), however this happens before the input
address is used (line 8 to mask off the low bits for the TLB
comparison, and line 12 to add the host-guest offset). If the input
address (addrl) also happens to have been placed in v0 (as in the second
column below), it gets clobbered before it is used.
addrl in t2 addrl in v0
1 srl a0,t2,0x7 srl a0,v0,0x7
2 andi a0,a0,0x1fe0 andi a0,a0,0x1fe0
3 addu a0,a0,s0 addu a0,a0,s0
4 lw at,9136(a0) lw at,9136(a0) set TCG_TMP0 (at)
5 lw v0,9140(a0) lw v0,9140(a0) set base (v0)
6 li t9,-4093 li t9,-4093
7 lw a0,9160(a0) lw a0,9160(a0) set addend (a0)
8 and t9,t9,t2 and t9,t9,v0 use addrl
9 bne at,t9,0x836d8c8 bne at,t9,0x836d838 use TCG_TMP0
10 nop nop
11 bne v0,t8,0x836d8c8 bne v0,a1,0x836d838 use base
12 addu v0,a0,t2 addu v0,a0,v0 use addrl, addend
13 lw t0,0(v0) lw t0,0(v0)
Fix by using TCG_TMP0 (at) as the temporary instead of v0 (base),
pushing the load on line 5 forward into the delay slot of the low
comparison (line 10). The early load of the addend on line 7 also needs
pushing even further for 64-bit targets, or it will clobber a0 before
we're done with it. The output for 32-bit targets is unaffected.
srl a0,v0,0x7
andi a0,a0,0x1fe0
addu a0,a0,s0
lw at,9136(a0)
-lw v0,9140(a0) load high comparator
li t9,-4093
-lw a0,9160(a0) load addend
and t9,t9,v0
bne at,t9,0x836d838
- nop
+ lw at,9140(a0) load high comparator
+lw a0,9160(a0) load addend
-bne v0,a1,0x836d838
+bne at,a1,0x836d838
addu v0,a0,v0
lw t0,0(v0)
Backports commit 33fca8589cf2aa7bf91564e6a8f26b3ba0910541 from qemu
The add2 code in the tcg_out_addsub2 function doesn't take into account
the case where rl == al == bl. In that case we can't compute the carry
after the addition. As it corresponds to a multiplication by 2, the
carry bit is the bit 31.
While this is a corner case, this prevents x86-64 guests to boot on a
MIPS host.
Backports commit c99d69694af4ed15b33e3f7c2e3ef6972c14358d from qemu
Commit 2b7ec66f fixed TCGMemOp masking following the MO_AMASK addition,
but two cases were forgotten in the TCG S390 backend.
Backports commit 3c8691f568f49bf623dcb2850464d4156d95e61b from qemu
Commit 2b7ec66f fixed TCGMemOp masking following the MO_AMASK addition,
but two cases were forgotten in the TCG MIPS backend.
Backports commit 4214a8cb7c15ec43d4b2a43ebf248b273a0f4d45 from qemu
For 32-bit guest, we load a 32-bit address from the TLB, so there is no
need to compensate for the low or high part. This fixes 32-bit guests on
big-endian hosts.
Backports commit e72c4fb81db52be881c9356f1c60e0a7817d2d32 from qemu
Make sure to not modify the branch target. This ensure that the
branch target is not corrupted during partial retranslation.
Backports commit cd3b29b745b0ff393b2d37317837bc726b8dacc8 from qemu
The usages of this define are pure TCG and there is no architecture
specific variation of the value. Localise it to the TCG engine to
remove another architecture agnostic piece from cpu-defs.h.
This follows on from a28177820a868eafda8fab007561cc19f41941f4 where
temp_buf was moved out of the CPU_COMMON obsoleting the need for
the super early definition.
Backports commit 6e0b07306d1793e8402dd218d2e38a7377b5fc27 from qemu
This will be used to size the TLB when more than 8 MMU modes are
used by the target. Limitations come from the limited size of
the immediate fields (which sometimes, as in the case of Aarch64,
extend to instructions that shift the immediate).
Backports commit 006f8638c62bca2b0caf609485f47fa5e14d8a3c from qemu
No code uses the cpu_pc_from_tb() function. Delete from tricore and
arm which each provide an unused implementation. Update the comment
in tcg.h to reflect that this is obsoleted by synchronize_from_tb.
Backports commit fee068e4f190a36ef3bda9aa7c802f90434ef8e5 from qemu
With an eye toward having this data replace the gen_opc_* arrays
that each target collects in order to enable restore_state_from_tb.
Backports commit 9aef40ed1f6e2bd794bbb3ba8c8b773e506334c9 from qemu
In ffc6372851d8631a9f9fa56ec613b3244dc635b9, we swapped the guest
base to the address base register from the address index register.
Except that 31 in the base slot is SP not XZR, so we need to be
more intelligent about which reg gets placed in which slot.
Backports commit 352bcb0a2b816ff9ab9d75d0f2384650d9e9ab19 from qemu
Rather than allow arbitrary shift+trunc, only concern ourselves
with low and high parts. This is all that was being used anyway.
Backports commit 609ad70562793937257c89d07bf7c1370b9fc9aa from qemu
They behave the same as ext32s_i64 and ext32u_i64 from the constant
folding and zero propagation point of view, except that they can't
be replaced by a mov, so we don't compute the affected value.
Backports commit 8bcb5c8f34f9215d4f88f388c7ff14c9bd5cecd3 from qemu
Implement real ext_i32_i64 and extu_i32_i64 ops. They ensure that a
32-bit value is always converted to a 64-bit value and not propagated
through the register allocator or the optimizer.
Backports commit 4f2331e5b67af8172419eb1c8db510b497b30a7b from qemu
The op is sometimes named trunc_shr_i32 and sometimes trunc_shr_i64_i32,
and the name in the README doesn't match the name offered to the
frontends.
Always use the long name to make it clear it is a size changing op.
Backports commit 0632e555fc4d281d69cb08d98d500d96185b041f from qemu
Instead of using an enum which could be either a copy or a const, track
them separately. This will be used in the next patch.
Constants are tracked through a bool. Copies are tracked by initializing
temp's next_copy and prev_copy to itself, allowing to simplify the code
a bit.
Backports commit b41059dd9deec367a4ccd296659f0bc5de2dc705 from qemu
Add two accessor functions temp_is_const and temp_is_copy, to make the
code more readable and make code change easier.
Backports commit d9c769c60948815ee03b2684b1c1c68ee4375149 from qemu
The tcg_temp_info structure uses 24 bytes per temp. Now that we emulate
vector registers on most guests, it's not uncommon to have more than 100
used temps. This means we have initialize more than 2kB at least twice
per TB, often more when there is a few goto_tb.
Instead used a TCGTempSet bit array to track which temps are in used in
the current basic block. This means there are only around 16 bytes to
initialize.
This improves the boot time of a MIPS guest on an x86-64 host by around
7% and moves out tcg_optimize from the the top of the profiler list.
Backports commit 1208d7dd5fddc1fbd98de800d17429b4e5578848 from qemu
By convention, on a 64-bit host TCG internally stores 32-bit constants
as sign-extended. This is not the case in the optimizer when a 32-bit
constant is folded.
This doesn't seem to have more consequences than suboptimal code
generation. For instance the x86 backend assumes sign-extended constants,
and in some rare cases uses a 32-bit unsigned immediate 0xffffffff
instead of a 8-bit signed immediate 0xff for the constant -1. This is
with a ppc guest:
before
------
---- 0x9f29cc
movi_i32 tmp1,$0xffffffff
movi_i32 tmp2,$0x0
add2_i32 tmp0,CA,CA,tmp2,r6,tmp2
add2_i32 tmp0,CA,tmp0,CA,tmp1,tmp2
mov_i32 r10,tmp0
0x7fd8c7dfe90c: xor %ebp,%ebp
0x7fd8c7dfe90e: mov %ebp,%r11d
0x7fd8c7dfe911: mov 0x18(%r14),%r9d
0x7fd8c7dfe915: add %r9d,%r10d
0x7fd8c7dfe918: adc %ebp,%r11d
0x7fd8c7dfe91b: add $0xffffffff,%r10d
0x7fd8c7dfe922: adc %ebp,%r11d
0x7fd8c7dfe925: mov %r11d,0x134(%r14)
0x7fd8c7dfe92c: mov %r10d,0x28(%r14)
after
-----
---- 0x9f29cc
movi_i32 tmp1,$0xffffffffffffffff
movi_i32 tmp2,$0x0
add2_i32 tmp0,CA,CA,tmp2,r6,tmp2
add2_i32 tmp0,CA,tmp0,CA,tmp1,tmp2
mov_i32 r10,tmp0
0x7f37010d490c: xor %ebp,%ebp
0x7f37010d490e: mov %ebp,%r11d
0x7f37010d4911: mov 0x18(%r14),%r9d
0x7f37010d4915: add %r9d,%r10d
0x7f37010d4918: adc %ebp,%r11d
0x7f37010d491b: add $0xffffffffffffffff,%r10d
0x7f37010d491f: adc %ebp,%r11d
0x7f37010d4922: mov %r11d,0x134(%r14)
0x7f37010d4929: mov %r10d,0x28(%r14)
Backports commit 29f3ff8d6cbc28f79933aeaa25805408d0984a8f from qemu
Due to a copy&paste, the new op value is tested against mov_i32 instead
of movi_i32. The test is therefore always false. Fix that.
Backports commit 961521261a3d600b0695b2e6d2b0f490076f7e90 from qemu
The tcg_constant_folding folding ends up doing all the optimizations
(which is a good thing to avoid looping on all ops multiple time), so
make it clear and just rename it tcg_optimize.
Backports commit 36e60ef6ac5d8a262d0fbeedfdb2b588514cb1ea from qemu
Most of the calls to tcg_opt_gen_mov are preceeded by a test to check if
the source temp is a constant. Fold that into the tcg_opt_gen_mov
function.
Backports commit 97a79eb70dd35a24fda87d86196afba5e6f21c5d from qemu
Each call to tcg_opt_gen_mov is preceeded by a test to check if the
source and destination temps are copies. Fold that into the
tcg_opt_gen_mov function.
Backports commit 5365718a9afeeabde3784d82a542f8ad909b18cf from qemu
We can get the opcode using the TCGOp pointer. It needs to be
dereferenced, but it's anyway done a few lines below to write
the new value.
Backports commit 8d6a91602ea824ef4435ea38fd475387eecc098c from qemu
We can get the opcode using the TCGOp pointer. It needs to be
dereferenced, but it's anyway done a few lines below to write
the new value.
Backports commit ebd27391b00cdafc81e0541a940686137b3b48df from qemu
Similar to the same fix for user-mode, except this instance
occurs on the softmmu path. Again, the tlb addend must be
the base register, while the guest address is the index.
Backports commit 80adb8fcad4778376a11d394a9e01516819e2327 from qemu
Thanks to the previous patch, it is now easy for tcg_out_qemu_ld and
tcg_out_qemu_st to use a 32-bit zero extended offset. However, the
guest base register x28 must be the base and addr_reg must be the
index.
Backports commit ffc6372851d8631a9f9fa56ec613b3244dc635b9 from qemu
The new argument lets you pick uxtw or uxtx mode for the offset
register. For now, all callers pass TCG_TYPE_I64 so that uxtx
is generated. The bits for uxtx are removed from I3312_TO_I3310.
Backports commit 6c0f0c0f124718650a8d682ba275044fc02f6fe2 from qemu
The addition of MO_AMASK means that places that used inverted masks
need to be changed to use positive masks, and places that failed to
mask the intended bits need updating.
Backports commit 2b7ec66f025263a5331f37d5ad78a625496fd7bd from qemu
These modifiers control, on a per-memory-op basis, whether
unaligned memory accesses are allowed. The default setting
reflects the target's definition of ALIGNED_ONLY.
Backports commit dfb36305626636e2e07e0c5acd3a002a5419399e from qemu
The extra information is not yet used but it is now available.
This requires minor changes through all of the tcg backends.
Backports commit 3972ef6f830d65e9bacbd31257abedc055fd6dc8 from qemu
At the tcg opcode level, not at the tcg-op.h generator level.
This requires minor changes through all of the tcg backends,
but none of the cpu translators.
Backports commit 59227d5d45bb3c31dc2118011691c35b3c00879c from qemu
This is less about improved type checking than enabling a
subsequent change to the representation of labels.
Backports commit bec1631100323fac0900aea71043d5c4e22fc2fa from qemu
This is improved type checking for the translators -- it's no longer
possible to accidentally swap arguments to the branch functions.
Note that the code generating backends still manipulate labels as int.
With notable exceptions, the scope of the change is just a few lines
for each target, so it's not worth building extra machinery to do this
change in per-target increments.
Backports commit 42a268c241183877192c376d03bd9b6d527407c7 from qemu
We no longer need INDEX_op_end to terminate the list, nor do we
need 5 forms of nop, since we just remove the TCGOp instead.
Backports commit 15fc7daa770764cc795158cbb525569f156f3659 from qemu
Rather reserving space in the op stream for optimization,
let the optimizer add ops as necessary.
Backports commit a4ce099a7a4b4734c372f6bf28f3362e370f23c1 from qemu
With the linked list scheme we need not leave nops in the stream
that we need to process later.
Backports commit 0c627cdca20155753a536c51385abb73941a59a0 from qemu
The method by which we count the number of ops emitted
is going to change. Abstract that away into some inlines.
Backports commit fe700adb3db5b028b504423b946d4ee5200a8f2f from qemu.
Almost completely eliminates the ifdefs in this file, improving
confidence in the lesser used 32-bit builds.
Backports commit 3a13c3f34ce2058e0c2decc3b0f9f56be24c9400 from qemu
Some of these functions are really quite large. We have a number of
things that ought to be circularly dependent, but we duplicated code
to break that chain for the inlines.
This saved 25% of the code size of one of the translators I examined.
Chain the temporaries together via pointers intstead of indices.
The mem_reg value is now mem_base->reg. This will be important later.
This does require that the frame pointer have a global temporary
allocated for it. This is simple bar the existing reserved_regs check.
Backports commit b3a62939561e07bc34493444fa926b6137cba4e8 from qemu
Thus, use cpu_env as the parameter, not TCG_AREG0 directly.
Update all uses in the translators.
Backports commit e1ccc05444676b92c63708096e36582be27fbee1 from qemu
