Pass float_status structure pointer to the pickNaN so that
machine-specific settings are available to NaN selection code.
Add use_first_nan property to float_status and use it in Xtensa-specific
pickNaN.
Backports commit 913602e3ffe6bf50b869a14028a55cb267645ba3
target/xtensa, the only user of NO_SIGNALING_NANS macro has FPU
implementations with and without the corresponding property. With
NO_SIGNALING_NANS being a macro they cannot be a part of the same QEMU
executable.
Replace macro with new property in float_status to allow cores with
different FPU implementations coexist.
Backports cc43c6925113c5bc8f1a0205375931d2e4807c99
Quoting ISO C99 6.7.8p4, "All the expressions in an initializer for an
object that has static storage duration shall be constant expressions or
string literals".
The compound literal produced by the make_floatx80() macro is not such a
constant expression, per 6.6p7-9. (An implementation may accept it,
according to 6.6p10, but is not required to.)
Therefore using "floatx80_zero" and make_floatx80() for initializing
"f2xm1_table" and "fpatan_table" is not portable. And gcc-4.8 in RHEL-7.6
actually chokes on them:
> target/i386/fpu_helper.c:871:5: error: initializer element is not constant
> { make_floatx80(0xbfff, 0x8000000000000000ULL),
> ^
We've had the make_floatx80_init() macro for this purpose since commit
3bf7e40ab914 ("softfloat: fix for C99", 2012-03-17), so let's use that
macro again.
Fixes: eca30647fc0 ("target/i386: reimplement f2xm1 using floatx80 operations")
Fixes: ff57bb7b632 ("target/i386: reimplement fpatan using floatx80 operations")
Backports commit 163b3d1af2552845a60967979aca8d78a6b1b088 from qemu
According to the comment, this definition of invalid encoding is given
by intel developer's manual, and doesn't comply with 680x0 FPU.
With m68k, the explicit integer bit can be zero in the case of:
- zeros (exp == 0, mantissa == 0)
- denormalized numbers (exp == 0, mantissa != 0)
- unnormalized numbers (exp != 0, exp < 0x7FFF)
- infinities (exp == 0x7FFF, mantissa == 0)
- not-a-numbers (exp == 0x7FFF, mantissa != 0)
For infinities and NaNs, the explicit integer bit can be either one or
zero.
The IEEE 754 standard does not define a zero integer bit. Such a number
is an unnormalized number. Hardware does not directly support
denormalized and unnormalized numbers, but implicitly supports them by
trapping them as unimplemented data types, allowing efficient conversion
in software.
See "M68000 FAMILY PROGRAMMER’S REFERENCE MANUAL",
"1.6 FLOATING-POINT DATA TYPES"
We will implement in the m68k TCG emulator the FP_UNIMP exception to
trap into the kernel to normalize the number. In case of linux-user,
the number will be normalized by QEMU.
Backports commit d159dd058c7dc48a9291fde92eaae52a9f26a4d1 from qemu
Both x87 and m68k need the low parts of the quotient for their
remainder operations. Arrange for floatx80_modrem to track those bits
and return them via a pointer.
The architectures using float32_rem and float64_rem do not appear to
need this information, so the *_rem interface is left unchanged and
the information returned only from floatx80_modrem. The logic used to
determine the low 7 bits of the quotient for m68k
(target/m68k/fpu_helper.c:make_quotient) appears completely bogus (it
looks at the result of converting the remainder to integer, the
quotient having been discarded by that point); this patch does not
change that, but the m68k maintainers may wish to do so.
Backports commit 445810ec915687d37b8ae0ef8d7340ab4a153efa from qemu
The m68k-specific softfloat code includes a function floatx80_mod that
is extremely similar to floatx80_rem, but computing the remainder
based on truncating the quotient toward zero rather than rounding it
to nearest integer. This is also useful for emulating the x87 fprem
and fprem1 instructions. Change the floatx80_rem implementation into
floatx80_modrem that can perform either operation, with both
floatx80_rem and floatx80_mod as thin wrappers available for all
targets.
There does not appear to be any use for the _mod operation for other
floating-point formats in QEMU (the only other architectures using
_rem at all are linux-user/arm/nwfpe, for FPA emulation, and openrisc,
for instructions that have been removed in the latest version of the
architecture), so no change is made to the code for other formats.
Backports commit 6b8b0136ab3018e4b552b485f808bf66bcf19ead from qemu
Replace the floatx80 compare specializations with inline functions
that call the standard floatx80_compare{,_quiet} functions.
Use bool as the return type.
Backports commit c6baf65000f826a713e8d9b5b35e617b0ca9ab5d from qemu
Replace the float128 compare specializations with inline functions
that call the standard float128_compare{,_quiet} functions.
Use bool as the return type.
Backports commit b7b1ac684fea49c6bfe1ad8b706aed7b09116d15 from qemu
Replace the float64 compare specializations with inline functions
that call the standard float64_compare{,_quiet} functions.
Use bool as the return type.
Backports commit 0673ecdf6cb2b1445a85283db8cbacb251c46516 from qemu
Replace the float32 compare specializations with inline functions
that call the standard float32_compare{,_quiet} functions.
Use bool as the return type.
Backports commit 5da2d2d8e53d80e92a61720ea995c86b33cbf25d from qemu
Give the previously unnamed enum a typedef name. Use it in the
prototypes of compare functions. Use it to hold the results
of the compare functions.
Backports commit 71bfd65c5fcd72f8af2735905415c7ce4220f6dc from qemu
Give the previously unnamed enum a typedef name. Use the packed
attribute so that we do not affect the layout of the float_status
struct. Use it in the prototypes of relevant functions.
Adjust switch statements as necessary to avoid compiler warnings.
Backports commit 3dede407cc61b64997f0c30f6dbf4df09949abc9 from qemu
Slightly tidies the usage within softfloat.c and the
representation in float_status.
Backports commit a828b373bdabc7e53d1e218e3fc76f85b6674688 from qemu
The macros use the "flags" type and to be consistent if anyone just
needs the macros we should bring in the header we need. There is an
outstanding TODO to audit the use of "flags" and replace with bool at
which point this include could be dropped.
Backports commit 5937fb63a92d54cc4e5270256e4387c4d3a70091 from qemu
There are a bunch of users of the inline helpers who do not need
access to the entire softfloat API. Move those inline helpers into a
new header file which can be included without bringing in the rest of
the world.
Backports commit e34c47ea3fb5f324b58db117b3c010a494c8d6ca from qemu
In our quest to eliminate the home rolled LIT64 macro we fixup usage
inside the softfloat code. While we are at it we remove some of the
extraneous spaces to closer fit the house style.
Backports commit e932112420f063776f2b9d9e5512830cd6890a7a from qemu
Handling it just like float128_to_uint32_round_to_zero, that hopefully
is free of bugs :)
Documentation basically copied from float128_to_uint64
Backports commit e45de9922e43c1ce4f4739b62142314a13029d5c from qemu
Needed on s390x, to test for the data class of a number. So it will
gain soon a user.
A number is considered normal if the exponent is neither 0 nor all 1's.
That can be checked by adding 1 to the exponent, and comparing against
>= 2 after dropping an eventual overflow into the sign bit.
While at it, convert the other floatXX_is_normal functions to use a
similar, less error prone calculation, as suggested by Richard H.
Backports commit 47393181604d507f4fe2a15a65b1eede0f974d6a from qemu
It has not had users since f83311e476 ("target-m68k: use floatx80
internally", 2017-06-21).
Note that no other bit-width has floatX_trunc_to_int.
Backports commit c953da8f0be5e026d1c9128660736d72294feb3e from qemu
Only MIPS requires snan_bit_is_one to be variable. While we are
specializing softfloat behaviour, allow other targets to eliminate
this runtime check.
Backports commit 03385dfdaaa2dc31bbd07d13244a6b037bfab4cc from qemu
This allows us to delete a lot of additional boilerplate
code which is no longer needed.
Backports commit 6fed16b265a4fcc810895bbca4d67e1ae7a89f07 from qemu
Solaris 9 was released in 2002, its successor Solaris 10 was
released in 2005, and Solaris 9 was end-of-lifed in 2014.
Nobody has stepped forward to express interest in supporting
Solaris of any flavour, so removing support for the ancient
versions seems uncontroversial.
In particular, this allows us to remove a use of 'uname'
in configure that won't work if you're cross-compiling.
Backports commit 91939262ffcd3c85ea6a4793d3029326eea1d649 from qemu
Since f3218a8 ("softfloat: add floatx80 constants")
floatx80_infinity is defined but never used.
This patch updates floatx80 functions to use
this definition.
This allows to define a different default Infinity
value on m68k: the m68k FPU defines infinity with
all bits set to zero in the mantissa.
Backports commit 0f605c889ca3fe9744166ad4149d0dff6dacb696 from qemu
Move fpu/softfloat-macros.h to include/fpu/
Export floatx80 functions to be used by target floatx80
specific implementations.
Exports:
propagateFloatx80NaN(), extractFloatx80Frac(),
extractFloatx80Exp(), extractFloatx80Sign(),
normalizeFloatx80Subnormal(), packFloatx80(),
roundAndPackFloatx80(), normalizeRoundAndPackFloatx80()
Also exports packFloat32() that will be used to implement
m68k fsinh, fcos, fsin, ftan operations.
Backports commit 88857aca93f6ec8f372fb9c8201394b0e5582034 from qemu
As some of the constants here will also be needed
elsewhere (specifically for the upcoming SVE support) we move them out
to softfloat.h.
Backports commit 026e2d6ef74000afb9049f46add4b94f594c8fb3 from qemu
Backports commit 2deb992b767d28035fac3b374c7730494ff0b43d from qemu
Also backports the fp16 changes introduced in commit f566c0474a9b9bbd9ed248607e4007e24d3358c0
This is a little bit of a departure from softfloat's original approach
as we skip the estimate step in favour of a straight iteration. There
is a minor optimisation to avoid calculating more bits of precision
than we need however this still brings a performance drop, especially
for float64 operations.
Backports commit c13bb2da9eedfbc5886c8048df1bc1114b285fb0 from qemu
The compare function was already expanded from a macro. I keep the
macro expansion but move most of the logic into a compare_decomposed.
Backports commit 0c4c90929143a530730e2879204a55a30bf63758 from qemu
Let's do the same re-factor treatment for minmax functions. I still
use the MACRO trick to expand but now all the checking code is common.
Backports commit 89360067071b1844bf745682e18db7dde74cdb8d from qemu
This is one of the simpler manipulations you could make to a floating
point number.
Backports commit 0bfc9f195209593e91a98cf2233753f56a2e5c02 from qemu
These are considerably simpler as the lower order integers can just
use the higher order conversion function. As the decomposed fractional
part is a full 64 bit rounding and inexact handling comes from the
pack functions.
Backports commit c02e1fb80b553d47420f7492de4bc590c2461a86 from qemu
We share the common int64/uint64_pack_decomposed function across all
the helpers and simply limit the final result depending on the final
size.
Backports commit ab52f973a504f8de0c5df64631ba4caea70a7d9e from qemu
We can now add float16_round_to_int and use the common round_decomposed and
canonicalize functions to have a single implementation for
float16/32/64 round_to_int functions.
Backports commit dbe4d53a590f5689772b683984588b3cf6df163e from qemu
