Commit Graph

258 Commits

Author SHA1 Message Date
Alex Bennée
dbe4d53a59 fpu/softfloat: re-factor round_to_int
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.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-21 10:21:16 +00:00
Alex Bennée
d446830a3a fpu/softfloat: re-factor muladd
We can now add float16_muladd and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 muladd functions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-21 10:21:11 +00:00
Alex Bennée
cf07323d49 fpu/softfloat: re-factor div
We can now add float16_div and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 versions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-21 10:21:06 +00:00
Alex Bennée
74d707e2cc fpu/softfloat: re-factor mul
We can now add float16_mul and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 versions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-21 10:20:59 +00:00
Alex Bennée
6fff216769 fpu/softfloat: re-factor add/sub
We can now add float16_add/sub and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 add and sub functions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-02-21 10:20:53 +00:00
Alex Bennée
a90119b5a2 fpu/softfloat: define decompose structures
These structures pave the way for generic softfloat helper routines
that will operate on fully decomposed numbers.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-02-21 10:20:45 +00:00
Alex Bennée
d97544c94a fpu/softfloat: move the extract functions to the top of the file
This is pure code-motion during re-factoring as the helpers will be
needed earlier.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-21 10:20:39 +00:00
Alex Bennée
13894527f5 fpu/softfloat: improve comments on ARM NaN propagation
Mention the pseudo-code fragment from which this is based.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-02-21 10:20:37 +00:00
Alex Bennée
210cbd4910 fpu/softfloat: implement float16_squash_input_denormal
This will be required when expanding the MINMAX() macro for 16
bit/half-precision operations.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-21 10:20:14 +00:00
Laurent Vivier
0f72129281 softfloat: define floatx80_round()
Add a function to round a floatx80 to the defined precision
(floatx80_rounding_precision)

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <20170628204241.32106-5-laurent@vivier.eu>
2017-06-29 20:27:39 +02:00
Laurent Vivier
e5b0cbe8e8 softfloat: define 680x0 specific values
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170611231633.32582-2-laurent@vivier.eu>
2017-06-15 09:15:38 +02:00
Peter Maydell
d000b477f2 softfloat: Use correct type in float64_to_uint64_round_to_zero()
In float64_to_uint64_round_to_zero() a typo meant that we were
taking the uint64_t return value from float64_to_uint64() and
putting it into an int64_t variable before returning it as
uint64_t again. Use uint64_t instead of pointlessly casting it
back and forth to int64_t.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-02-28 09:03:38 +03:00
Bharata B Rao
fd425037d2 softfloat: Add float128_to_uint32_round_to_zero()
float128_to_uint32_round_to_zero() is needed by xscvqpuwz instruction
of PowerPC ISA 3.0.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-02-22 11:28:28 +11:00
Bharata B Rao
2e6d856835 softfloat: Add float128_to_uint64_round_to_zero()
Implement float128_to_uint64() and use that to implement
float128_to_uint64_round_to_zero()

This is required by xscvqpudz instruction of PowerPC ISA 3.0.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-02-22 11:28:28 +11:00
Bharata B Rao
9ee6f678f4 softfloat: Add round-to-odd rounding mode
Power ISA 3.0 introduces a few quadruple precision floating point
instructions that support round-to-odd rounding mode. The
round-to-odd mode is explained as under:

Let Z be the intermediate arithmetic result or the operand of a convert
operation. If Z can be represented exactly in the target format, the
result is Z. Otherwise the result is either Z1 or Z2 whichever is odd.
Here Z1 and Z2 are the next larger and smaller numbers representable
in the target format respectively.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-02-22 11:28:28 +11:00
Bharata B Rao
5d51eaea84 softfloat: Fix the default qNAN for target-ppc
Currently float128_default_nan() returns 0xFFFF800000000000 in the
higher double word, but it should return 0x7FFF800000000000 which
is the correct higher double word for default qNAN on PowerPC.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-01-31 10:10:14 +11:00
Richard Henderson
005fa38d86 target-hppa: Add softfloat specializations
Like the original MIPS, HPPA has the MSB of an SNaN set.
However, it has different rules for silencing an SNaN:
(1) msb is cleared and (2) msb-1 must be set if the fraction
is now zero, and (implementation defined) may be set always.
I haven't checked real hardware but chose the set always
alternative because it's easy and within spec.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-23 09:52:40 -08:00
Andrew Dutcher
d1eb8f2acb fpu: add mechanism to check for invalid long double formats
All operations that take a floatx80 as an operand need to have their
inputs checked for malformed encodings. In all of these cases, use the
function floatx80_invalid_encoding to perform the check. If an invalid
operand is found, raise an invalid operation exception, and then return
either NaN (for fp-typed results) or the integer indefinite value (the
minimum representable signed integer value, for int-typed results).

For the non-quiet comparison operations, this touches adjacent code in
order to pass style checks.

Signed-off-by: Andrew Dutcher <andrew@andrewdutcher.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1471392895-17324-1-git-send-email-andrew@andrewdutcher.com
[PMM: changed "1 << 63" to "1ULL << 63" to fix compile errors]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-09-15 12:43:18 +01:00
Pranith Kumar
dfd6076710 softfloat: Fix warn about implicit conversion from int to int8_t
Change the flag type to 'uint8_t' to fix the implicit conversion error.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Message-id: 20160810185502.32015-1-bobby.prani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-08-15 16:15:38 +01:00
Aleksandar Markovic
c27644f0e9 softfloat: Handle snan_bit_is_one == 0 in MIPS pickNaNMulAdd()
Only for Mips platform, and only for cases when snan_bit_is_one is 0,
correct the order of argument comparisons in pickNaNMulAdd().

For more info, see [1], page 53, section "3.5.3 NaN Propagation".

[1] "MIPS Architecture for Programmers Volume IV-j:
    The MIPS32 SIMD Architecture Module",
    Imagination Technologies LTD, Revision 1.12, February 3, 2016

Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[leon.alrae@imgtec.com:
 * reworded the subject of the patch
 * swapped if/else code blocks to match the commit description]
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2016-06-24 13:41:32 +01:00
Aleksandar Markovic
a7c04d545a softfloat: For Mips only, correct default NaN values
Only for Mips platform, and only for cases when snan_bit_is_one is 0,
correct default NaN values (in their 16-, 32-, and 64-bit flavors).

For more info, see [1], page 84, Table 6.3 "Value Supplied When a New
Quiet NaN Is Created", and [2], page 52, Table 3.7 "Default NaN
Encodings".

[1] "MIPS Architecture For Programmers Volume II-A:
    The MIPS64 Instruction Set Reference Manual",
    Imagination Technologies LTD, Revision 6.04, November 13, 2015

[2] "MIPS Architecture for Programmers Volume IV-j:
    The MIPS32 SIMD Architecture Module",
    Imagination Technologies LTD, Revision 1.12, February 3, 2016

Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2016-06-24 13:41:31 +01:00
Aleksandar Markovic
a59eaea646 softfloat: Clean code format in fpu/softfloat-specialize.h
fpu/softfloat-specialize.h is the most critical file in SoftFloat
library, since it handles numerous differences between platforms in
relation to floating point arithmetics. This patch makes the code
in this file more consistent format-wise, and hopefully easier to
debug and maintain.

Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2016-06-24 13:41:30 +01:00
Aleksandar Markovic
af39bc8c49 softfloat: Implement run-time-configurable meaning of signaling NaN bit
This patch modifies SoftFloat library so that it can be configured in
run-time in relation to the meaning of signaling NaN bit, while, at the
same time, strictly preserving its behavior on all existing platforms.

Background:

In floating-point calculations, there is a need for denoting undefined or
unrepresentable values. This is achieved by defining certain floating-point
numerical values to be NaNs (which stands for "not a number"). For additional
reasons, virtually all modern floating-point unit implementations use two
kinds of NaNs: quiet and signaling. The binary representations of these two
kinds of NaNs, as a rule, differ only in one bit (that bit is, traditionally,
the first bit of mantissa).

Up to 2008, standards for floating-point did not specify all details about
binary representation of NaNs. More specifically, the meaning of the bit
that is used for distinguishing between signaling and quiet NaNs was not
strictly prescribed. (IEEE 754-2008 was the first floating-point standard
that defined that meaning clearly, see [1], p. 35) As a result, different
platforms took different approaches, and that presented considerable
challenge for multi-platform emulators like QEMU.

Mips platform represents the most complex case among QEMU-supported
platforms regarding signaling NaN bit. Up to the Release 6 of Mips
architecture, "1" in signaling NaN bit denoted signaling NaN, which is
opposite to IEEE 754-2008 standard. From Release 6 on, Mips architecture
adopted IEEE standard prescription, and "0" denotes signaling NaN. On top of
that, Mips architecture for SIMD (also known as MSA, or vector instructions)
also specifies signaling bit in accordance to IEEE standard. MSA unit can be
implemented with both pre-Release 6 and Release 6 main processor units.

QEMU uses SoftFloat library to implement various floating-point-related
instructions on all platforms. The current QEMU implementation allows for
defining meaning of signaling NaN bit during build time, and is implemented
via preprocessor macro called SNAN_BIT_IS_ONE.

On the other hand, the change in this patch enables SoftFloat library to be
configured in run-time. This configuration is meant to occur during CPU
initialization, at the moment when it is definitely known what desired
behavior for particular CPU (or any additional FPUs) is.

The change is implemented so that it is consistent with existing
implementation of similar cases. This means that structure float_status is
used for passing the information about desired signaling NaN bit on each
invocation of SoftFloat functions. The additional field in float_status is
called snan_bit_is_one, which supersedes macro SNAN_BIT_IS_ONE.

IMPORTANT:

This change is not meant to create any change in emulator behavior or
functionality on any platform. It just provides the means for SoftFloat
library to be used in a more flexible way - in other words, it will just
prepare SoftFloat library for usage related to Mips platform and its
specifics regarding signaling bit meaning, which is done in some of
subsequent patches from this series.

Further break down of changes:

  1) Added field snan_bit_is_one to the structure float_status, and
     correspondent setter function set_snan_bit_is_one().

  2) Constants <float16|float32|float64|floatx80|float128>_default_nan
     (used both internally and externally) converted to functions
     <float16|float32|float64|floatx80|float128>_default_nan(float_status*).
     This is necessary since they are dependent on signaling bit meaning.
     At the same time, for the sake of code cleanup and simplicity, constants
     <floatx80|float128>_default_nan_<low|high> (used only internally within
     SoftFloat library) are removed, as not needed.

  3) Added a float_status* argument to SoftFloat library functions
     XXX_is_quiet_nan(XXX a_), XXX_is_signaling_nan(XXX a_),
     XXX_maybe_silence_nan(XXX a_). This argument must be present in
     order to enable correct invocation of new version of functions
     XXX_default_nan(). (XXX is <float16|float32|float64|floatx80|float128>
     here)

  4) Updated code for all platforms to reflect changes in SoftFloat library.
     This change is twofolds: it includes modifications of SoftFloat library
     functions invocations, and an addition of invocation of function
     set_snan_bit_is_one() during CPU initialization, with arguments that
     are appropriate for each particular platform. It was established that
     all platforms zero their main CPU data structures, so snan_bit_is_one(0)
     in appropriate places is not added, as it is not needed.

[1] "IEEE Standard for Floating-Point Arithmetic",
    IEEE Computer Society, August 29, 2008.

Signed-off-by: Thomas Schwinge <thomas@codesourcery.com>
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Tested-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Tested-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[leon.alrae@imgtec.com:
 * cherry-picked 2 chunks from patch #2 to fix compilation warnings]
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2016-06-24 13:40:37 +01:00
Bastian Koppelmann
996a729f9b target-tricore: Add FPU infrastructure
This patch adds a file for all the FPU related helpers with all the includes,
useful defines, and a function to update the status bits. Additionally it adds
a mask for the rounding mode bits of PSW as well as all the opcodes for the
FPU instructions.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Message-Id: <1457708597-3025-2-git-send-email-kbastian@mail.uni-paderborn.de>
2016-03-23 09:22:48 +01:00
Peter Maydell
0c48262d47 fpu: Use plain 'int' rather than 'int_fast16_t' for exponents
Use the plain 'int' type rather than 'int_fast16_t' for handling
exponents. Exponents don't need to be exactly 16 bits, so using int16_t
for them would confuse more than it clarified.

This should be a safe change because int_fast16_t semantics
permit use of 'int' (and on 32-bit glibc that is what you get).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Message-id: 1453807806-32698-4-git-send-email-peter.maydell@linaro.org
2016-02-19 16:27:22 +00:00
Peter Maydell
07d792d2b0 fpu: Use plain 'int' rather than 'int_fast16_t' for shift counts
Use the plain 'int' type rather than 'int_fast16_t' for shift counts
in the various shift related functions, since we don't actually care
about the size of the integer at all here, and using int16_t would
be confusing.

This should be a safe change because int_fast16_t semantics
permit use of 'int' (and on 32-bit glibc that is what you get).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Message-id: 1453807806-32698-3-git-send-email-peter.maydell@linaro.org
2016-02-19 16:27:22 +00:00
Peter Maydell
0bb721d721 fpu: Remove use of int_fast16_t in conversions to int16
Make the functions which convert floating point to 16 bit integer
return int16_t rather than int_fast16_t, and correspondingly use
int_fast16_t in their internal implementations where appropriate.

(These functions are used only by the ARM target.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Message-id: 1453807806-32698-2-git-send-email-peter.maydell@linaro.org
2016-02-19 16:27:21 +00:00
Peter Maydell
d38ea87ac5 all: Clean up includes
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.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1454089805-5470-16-git-send-email-peter.maydell@linaro.org
2016-02-04 17:41:30 +00:00
Aurelien Jarno
7ceac86f49 softfloat: fix return type of roundAndPackFloat16
The roundAndPackFloat16 function should return a float16 value, not a
float32 one. Fix that.

Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1452700993-6570-1-git-send-email-aurelien@aurel32.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-01-22 15:09:21 +00:00
Peter Maydell
8f506c709a fpu: Replace int8 typedef with int8_t
Replace the int8 softfloat-specific typedef with int8_t.
This change was made with

find include hw fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\bint8\b/int8_t/g'

together with manual removal of the typedef definition, and
manual undoing of various mis-hits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Message-id: 1452603315-27030-6-git-send-email-peter.maydell@linaro.org
2016-01-22 15:09:21 +00:00
Peter Maydell
3a87d00910 fpu: Replace uint32 typedef with uint32_t
Replace the uint32 softfloat-specific typedef with uint32_t.
This change was made with

find include hw fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\buint32\b/uint32_t/g'

together with manual removal of the typedef definition,
manual undoing of various mis-hits, and another couple of
fixes found via test compilation.

All the uses in hw/ were using the wrong type by mistake.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Message-id: 1452603315-27030-5-git-send-email-peter.maydell@linaro.org
2016-01-22 15:09:21 +00:00
Peter Maydell
f4014512cd fpu: Replace int32 typedef with int32_t
Replace the int32 softfloat-specific typedef with int32_t.
This change was made with

find hw include fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\bint32\b/int32_t/g'

together with manual removal of the typedef definition, and
manual undoing of some mis-hits where macro arguments were
being used for token pasting rather than as a type.

The uses in hw/ipmi/ should not have been using this type at all.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Message-id: 1452603315-27030-4-git-send-email-peter.maydell@linaro.org
2016-01-22 15:09:21 +00:00
Peter Maydell
182f42fdc2 fpu: Replace uint64 typedef with uint64_t
Replace the uint64 softfloat-specific typedef with uint64_t.
This change was made with

find include fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\buint64\b/uint64_t/g'

together with manual removal of the typedef definition, and
manual undoing of some mis-hits where macro arguments were
being used for token pasting rather than as a type.

Note that the target-mips/kvm.c and target-s390x/kvm.c changes are fixing
code that should not have been using the uint64 type in the first place.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Message-id: 1452603315-27030-3-git-send-email-peter.maydell@linaro.org
2016-01-22 15:09:20 +00:00
Peter Maydell
f42c222482 fpu: Replace int64 typedef with int64_t
Replace the int64 softfloat-specific typedef with int64_t.
This change was made with

find include fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\bint64\b/int64_t/g'

together with manual removal of the typedef definition, and
manual undoing of some mis-hits where macro arguments were
being used for token pasting rather than as a type.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Message-id: 1452603315-27030-2-git-send-email-peter.maydell@linaro.org
2016-01-22 15:09:20 +00:00
Aurelien Jarno
2daea9c16f target-s390x: define default NaN values
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-06-05 01:37:58 +02:00
Peter Maydell
a2f2d288b5 softfloat: expand out STATUS macro
Expand out and remove the STATUS macro.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2015-02-06 16:11:38 +00:00
Peter Maydell
ff32e16e86 softfloat: expand out STATUS_VAR
Expand out and remove the STATUS_VAR macro.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2015-02-06 16:11:38 +00:00
Peter Maydell
e5a41ffa87 softfloat: Expand out the STATUS_PARAM macro
Expand out STATUS_PARAM wherever it is used and delete the definition.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2015-02-06 16:11:38 +00:00
Peter Maydell
16017c4854 softfloat: Clarify license status
The code in the softfloat source files is under a mixture of
licenses: the original code and many changes from QEMU contributors
are under the base SoftFloat-2a license; changes from Stefan Weil
and RedHat employees are GPLv2-or-later; changes from Fabrice Bellard
are under the BSD license. Clarify this in the comments at the
top of each affected source file, including a statement about
the assumed licensing for future contributions, so we don't need
to remember to ask patch submitters explicitly to pick a license.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Andreas Färber <afaerber@suse.de>
Acked-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Avi Kivity <avi.kivity@gmail.com>
Acked-by: Ben Taylor <bentaylor.solx86@gmail.com>
Acked-by: Blue Swirl <blauwirbel@gmail.com>
Acked-by: Christophe Lyon <christophe.lyon@st.com>
Acked-by: Fabrice Bellard <fabrice@bellard.org>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Juan Quintela <quintela@redhat.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Paul Brook <paul@codesourcery.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Richard Henderson <rth@twiddle.net>
Acked-by: Richard Sandiford <rdsandiford@googlemail.com>
Acked-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-5-git-send-email-peter.maydell@linaro.org
2015-01-29 16:45:45 +00:00
Peter Maydell
332d584970 softfloat: Revert and reimplement remaining parts of b645bb4885 and 5a6932d51d
Revert the parts of commits b645bb4885 and 5a6932d51d which are still
in the codebase and under a SoftFloat-2b license.

Reimplement support for architectures where the most significant bit
in the mantissa is 1 for a signaling NaN rather than a quiet NaN,
by adding handling for SNAN_BIT_IS_ONE being set to the functions
which test values for NaN-ness.

This includes restoring the bugfixes lost in the reversion where
some of the float*_is_quiet_nan() functions were returning true
for both signaling and quiet NaNs.

[This is a mechanical squashing together of two separate "revert"
and "reimplement" patches.]

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-4-git-send-email-peter.maydell@linaro.org
2015-01-29 16:45:33 +00:00
Peter Maydell
6bb8e0f130 softfloat: Revert and reimplement remaining portions of 75d62a5856 and 3430b0be36
Revert the remaining portions of commits 75d62a5856 and 3430b0be36
which are under a SoftFloat-2b license, ie the functions
uint64_to_float32() and uint64_to_float64(). (The float64_to_uint64()
and float64_to_uint64_round_to_zero() functions were completely
rewritten in commits fb3ea83aa and 0a87a3107d so can stay.)

Reimplement from scratch the uint64_to_float64() and uint64_to_float32()
conversion functions.

[This is a mechanical squashing together of two separate "revert"
and "reimplement" patches.]

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-3-git-send-email-peter.maydell@linaro.org
2015-01-29 15:05:28 +00:00
Peter Maydell
a7d1ac78e0 softfloat: Apply patch corresponding to rebasing to softfloat-2a
This commit applies the changes to master which correspond to
replacing commit 158142c2c2 with a set of changes made by:
 * taking the SoftFloat-2a release
 * mechanically transforming the block comment style
 * reapplying Fabrice's original changes from 158142c2c2

This commit was created by:
 diff -u 158142c2c2 import-sf-2a
 patch  -p1 --fuzz 10 <../relicense-patch.txt
(where import-sf-2a is the branch resulting from the changes above).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-2-git-send-email-peter.maydell@linaro.org
2015-01-29 15:05:28 +00:00
Leon Alrae
2d31e0607d softfloat: add functions corresponding to IEEE-2008 min/maxNumMag
Add abs argument to the existing softfloat minmax() function and define
new float{32,64}_{min,max}nummag functions.

minnummag(x,y) returns x if |x| < |y|,
               returns y if |y| < |x|,
               otherwise minnum(x,y)

maxnummag(x,y) returns x if |x| > |y|,
               returns y if |y| > |x|,
               otherwise maxnum(x,y)

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
2014-10-14 13:28:51 +01:00
Luiz Capitulino
a49db98d1f fpu: softfloat: drop INLINE macro
This commit expands all uses of the INLINE macro and drop it.

The reason for this is to avoid clashes with external libraries with
bad name conventions and also because renaming keywords is not a good
practice.

PS: I'm fine with this change to be licensed under softfloat-2a or
softfloat-2b.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-23 11:00:12 -04:00
Tom Musta
a13d448968 softfloat: Introduce float32_to_uint64_round_to_zero
This change adds the float32_to_uint64_round_to_zero function to the softfloat
library.  This function fills out the complement of float32 to INT round-to-zero
conversion rountines, where INT is {int32_t, uint32_t, int64_t, uint64_t}.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Tested-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-04-08 11:20:00 +02:00
Alex Bennée
7baeabce1d softfloat: export squash_input_denormal functions
I need these available outside of softfloat for some of the reciprocal
processing in aarch64 helper functions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1394822294-14837-20-git-send-email-peter.maydell@linaro.org
2014-03-17 16:31:51 +00:00
Peter Maydell
67d43538ae softfloat: Support halving the result of muladd operation
The ARMv8 instruction set includes a fused floating point
reciprocal square root step instruction which demands an
"(x * y + z) / 2" fused operation. Support this by adding
a flag to the softfloat muladd operations which requests
that the result is halved before rounding.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-02-20 10:35:50 +00:00
Peter Maydell
f9288a76f1 softfloat: Add support for ties-away rounding
IEEE754-2008 specifies a new rounding mode:

"roundTiesToAway: the floating-point number nearest to the infinitely
precise result shall be delivered; if the two nearest floating-point
numbers bracketing an unrepresentable infinitely precise result are
equally near, the one with larger magnitude shall be delivered."

Implement this new mode (it is needed for ARM). The general principle
is that the required code is exactly like the ties-to-even code,
except that we do not need to do the "in case of exact tie clear LSB
to round-to-even", because the rounding operation naturally causes
the exact tie to round up in magnitude.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
dc355b764d softfloat: Refactor code handling various rounding modes
Refactor the code in various functions which calculates rounding
increments given the current rounding mode, so that instead of a
set of nested if statements we have a simple switch statement.
This will give us a clean place to add the case for the new
tiesAway rounding mode.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
14c9a07eb9 softfloat: Add float16 <=> float64 conversion functions
Add the conversion functions float16_to_float64() and
float64_to_float16(), which will be needed for the ARM
A64 instruction set.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
c4a1c5e7e2 softfloat: Factor out RoundAndPackFloat16 and NormalizeFloat16Subnormal
In preparation for adding conversions between float16 and float64,
factor out code currently done inline in the float16<=>float32
conversion functions into functions RoundAndPackFloat16 and
NormalizeFloat16Subnormal along the lines of the existing versions
for the other float types.

Note that we change the handling of zExp from the inline code
to match the API of the other RoundAndPackFloat functions; however
we leave the positioning of the binary point between bits 22 and 23
rather than shifting it up to the high end of the word.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
879d096b37 softfloat: Provide complete set of accessors for fp state
Tidy up the get/set accessors for the fp state to add missing ones
and make them all inline in softfloat.h rather than some inline and
some not.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Tom Musta
fd728f2f94 softfloat: Fix float64_to_uint32_round_to_zero
The float64_to_uint32_round_to_zero routine is incorrect.

For example, the following test pattern:

    425F81378DC0CD1F / 0x1.f81378dc0cd1fp+38

will erroneously set the inexact flag.

This patch re-implements the routine to use the float64_to_uint64_round_to_zero
routine.  If saturation occurs we ignore any flags set by the
conversion function and raise only Invalid.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Message-id: 1387397961-4894-6-git-send-email-tommusta@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Tom Musta
5e7f654fa1 softfloat: Fix float64_to_uint32
The float64_to_uint32 has several flaws:

 - for numbers between 2**32 and 2**64, the inexact exception flag
   may get incorrectly set.  In this case, only the invalid flag
   should be set.

       test pattern: 425F81378DC0CD1F / 0x1.f81378dc0cd1fp+38

 - for numbers between 2**63 and 2**64, incorrect results may
   be produced:

       test pattern: 43EAAF73F1F0B8BD / 0x1.aaf73f1f0b8bdp+63

This patch re-implements float64_to_uint32 to re-use the
float64_to_uint64 routine (instead of float64_to_int64).  For the
saturation case, we ignore any flags which the conversion routine
has set and raise only the invalid flag.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Message-id: 1387397961-4894-5-git-send-email-tommusta@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Tom Musta
0a87a3107d softfloat: Fix float64_to_uint64_round_to_zero
The float64_to_uint64_round_to_zero routine is incorrect.

For example, the following test pattern:

    46697351FF4AEC29 / 0x1.97351ff4aec29p+103

currently produces 8000000000000000 instead of FFFFFFFFFFFFFFFF.

This patch re-implements the routine to temporarily force the
rounding mode and use the float64_to_uint64 routine.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Message-id: 1387397961-4894-4-git-send-email-tommusta@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Tom Musta
2f18bbf984 softfloat: Add float32_to_uint64()
This patch adds the float32_to_uint64() routine, which converts a
32-bit floating point number to an unsigned 64 bit number.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: removed harmless but silly int64_t casts]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
3c85c37f25 softfloat: Fix factor 2 error for scalbn on denormal inputs
If the input to float*_scalbn() is denormal then it represents
a number 0.[mantissabits] * 2^(1-exponentbias) (and the actual
exponent field is all zeroes). This means that when we convert
it to our unpacked encoding the unpacked exponent must be one
greater than for a normal number, which represents
1.[mantissabits] * 2^(e-exponentbias) for an exponent field e.

This meant we were giving answers too small by a factor of 2 for
all denormal inputs.

Note that the float-to-int routines also have this behaviour
of not adjusting the exponent for denormals; however there it is
harmless because denormals will all convert to integer zero anyway.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
34e1c27bc3 softfloat: Only raise Invalid when conversions to int are out of range
We implement a number of float-to-integer conversions using conversion
to an integer type with a wider range and then a check against the
narrower range we are actually converting to. If we find the result to
be out of range we correctly raise the Invalid exception, but we must
also suppress other exceptions which might have been raised by the
conversion function we called.

This won't throw away exceptions we should have preserved, because for
the 'core' exception flags the IEEE spec mandates that the only valid
combinations of exception that can be raised by a single operation are
Inexact + Overflow and Inexact + Underflow. For the non-IEEE softfloat
flag for input denormals, we can guarantee that that flag won't have
been set for out of range float-to-int conversions because a squashed
denormal by definition goes to plus or minus zero, which is always in
range after conversion to integer zero.

This bug has been fixed for some of the float-to-int conversion routines
by previous patches; fix it for the remaining functions as well, so
that they all restore the pre-conversion status flags prior to raising
Invalid.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Tom Musta
fb3ea83aa5 softfloat: Fix float64_to_uint64
The comment preceding the float64_to_uint64 routine suggests that
the implementation is broken.  And this is, indeed, the case.

This patch properly implements the conversion of a 64-bit floating
point number to an unsigned, 64 bit integer.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
c4850f9e1b softfloat: Make the int-to-float functions take exact-width types
Currently the int-to-float functions take types which are specified
as "at least X bits wide", rather than "exactly X bits wide". This is
confusing and unhelpful since it means that the callers have to include
an explicit cast to [u]intXX_t to ensure the correct behaviour. Fix
them all to take the exactly-X-bits-wide types instead.

Note that this doesn't change behaviour at all since at the moment
we happen to define the 'int32' and 'uint32' types as exactly 32 bits
wide, and the 'int64' and 'uint64' types as exactly 64 bits wide.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Will Newton
f581bf5474 softfloat: Add float to 16bit integer conversions.
ARMv8 requires support for converting 32 and 64bit floating point
values to signed and unsigned 16bit integers.

Signed-off-by: Will Newton <will.newton@linaro.org>
[PMM: updated not to incorrectly set Inexact for Invalid inputs]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Peter Maydell
38970efafd softfloat: Fix exception flag handling for float32_to_float16()
Our float32 to float16 conversion routine was generating the correct
numerical answers, but not always setting the right set of exception
flags. Fix this, mostly by rearranging the code to more closely
resemble RoundAndPackFloat*, and in particular:
 * non-IEEE halfprec always raises Invalid for input NaNs
 * we need to check for the overflow case before underflow
 * we weren't getting the tininess-detected-after-rounding
   case correct (somewhat academic since only ARM uses halfprec
   and it is always tininess-detected-before-rounding)
 * non-IEEE halfprec overflow raises only Invalid, not
   Invalid + Inexact
 * we weren't setting Inexact when we should

Also add some clarifying comments about what the code is doing.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08 19:07:22 +00:00
Will Newton
e17ab310e9 softfloat: Add minNum() and maxNum() functions to softfloat.
Add floatnn_minnum() and floatnn_maxnum() functions which are equivalent
to the minNum() and maxNum() functions from IEEE 754-2008. They are
similar to min() and max() but differ in the handling of QNaN arguments.

Signed-off-by: Will Newton <will.newton@linaro.org>
Message-id: 1386158099-9239-5-git-send-email-will.newton@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2013-12-10 13:28:50 +00:00
Will Newton
e70614eaa0 softfloat: Remove unused argument from MINMAX macro.
The nan_exp argument is not used, so remove it.

Signed-off-by: Will Newton <will.newton@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1386158099-9239-4-git-send-email-will.newton@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2013-12-10 13:28:50 +00:00
Peter Maydell
4039736e6f softfloat: Fix shift128Right for shift counts 64..127
shift128Right would give the wrong result for a shift count
between 64 and 127. This was never noticed because all of
our uses of this function are guaranteed not to use shift
counts in this range.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1370186269-24353-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-10 11:36:12 -05:00
Peter Maydell
e3d142d073 fpu: Correct edgecase in float64_muladd
In handling float64_muladd, if we end up doing a subtraction of the
product and c, and the 128 bit result of this subtraction happens to
have its most significant bit in bit 63, we weren't handling this
correctly when attempting to normalize to put the most significant
bit into bit 126.  We would end up doing a right shift by a negative
number (undefined behaviour in C) so at best we would return an
incorrect result to the guest.  MSB in bit 63 has to be handled as a
special case separately from MSB in 0..62 and MSB in 63..126.  (MSB
in 127 is not possible.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2013-04-15 16:06:15 +02:00
Richard Sandiford
a6e7c18476 softfloat: Handle float_muladd_negate_c when product is zero
Honour float_muladd_negate_c in the case where the product is zero and
c is nonzero.  Previously we would fail to negate c.

Seen in (and tested against) the gfortran testsuite on MIPS.

Signed-off-by: Richard Sandiford <rdsandiford@googlemail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-01-26 13:22:09 +00:00
Richard Henderson
1e397eadf1 softfloat: Implement uint64_to_float128
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-01-05 10:12:50 +00:00
Richard Henderson
17ed229379 softfloat: Fix uint64_to_float64
The interface to normalizeRoundAndPackFloat64 requires that the
high bit be clear.  Perform one shift-right-and-jam if needed.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-01-05 10:12:49 +00:00
Paolo Bonzini
6b4c305cbd fpu: move public header file to include/fpu
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:46 +01:00
Paolo Bonzini
1de7afc984 misc: move include files to include/qemu/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:39 +01:00
Aurelien Jarno
bbc1dedef6 softfloat: implement fused multiply-add NaN propagation for MIPS
Add a pickNaNMulAdd function for MIPS, implementing NaN propagation
rules for MIPS fused multiply-add instructions.

Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2012-10-31 22:20:45 +01:00
Peter Maydell
e744c06fca fpu/softfloat.c: Return correctly signed values from uint64_to_float32
The uint64_to_float32() conversion function was incorrectly always
returning numbers with the sign bit set (ie negative numbers). Correct
this so we return positive numbers instead.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2012-10-01 22:06:39 +02:00
Peter Maydell
4be8eeacb9 fpu/softfloat.c: Remove pointless shift of always-zero value
In float16_to_float32, when returning an infinity, just pass zero
as the mantissa argument to packFloat32(), rather than shifting
a value which we know must be zero.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2012-10-01 22:06:39 +02:00
Max Filippov
b81fe822da target-xtensa: specialize softfloat NaN rules
NaN propagation rule: leftmost NaN in the expression gets propagated to
the result.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-09-22 17:59:12 +00:00
Max Filippov
213ff4e6df softfloat: add NO_SIGNALING_NANS
Architectures that don't have signaling NaNs can define
NO_SIGNALING_NANS, it will make float*_is_quiet_nan return 1 for any NaN
and float*_is_signaling_nan always return 0.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-09-22 17:59:12 +00:00
Max Filippov
6617680296 softfloat: make float_muladd_negate_* flags independent
Flags passed into float{32,64}_muladd are treated as bits; assign
independent bits to float_muladd_negate_* to allow precise control over
what gets negated in float{32,64}_muladd.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-09-22 17:59:12 +00:00
Andreas Färber
94a49d86c5 softfloat: Replace int16 type with int_fast16_t
Based on the following Coccinelle patch:

@@
typedef int16, int_fast16_t;
@@
-int16
+int_fast16_t

Avoids a workaround for AIX.

Add typedef for pre-10 Solaris.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Cc: malc <av1474@comtv.ru>
Cc: Ben Taylor <bentaylor.solx86@gmail.com>
Tested-by: Bernhard Walle <bernhard@bwalle.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-04-28 09:13:26 +00:00
Andreas Färber
5aea4c589a softfloat: Replace uint16 type with uint_fast16_t
Based on the following Coccinelle patch:

@@
typedef uint16, uint_fast16_t;
@@
-uint16
+uint_fast16_t

Fixes the build of the Cocoa frontend on Mac OS X and avoids a
workaround for AIX.

For pre-10 Solaris include osdep.h.

Reported-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
Reported-by: Rui Carmo <rui.carmo@gmail.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Cc: Juan Pineda <juan@logician.com>
Cc: malc <av1474@comtv.ru>
Cc: Ben Taylor <bentaylor.solx86@gmail.com>
Tested-by: Bernhard Walle <bernhard@bwalle.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-04-28 09:13:09 +00:00
Andreas Färber
c9696547d4 softfloat: Fix mixups of int and int16
normalizeFloat{32,64}Subnormal() expect the exponent as int16, not int.
This went unnoticed since int16 and uint16 were both typedef'ed to int.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Bernhard Walle <bernhard@bwalle.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-04-28 09:12:24 +00:00
Juan Quintela
0eb4fc817f softfloat: make USE_SOFTFLOAT_STRUCT_TYPES compile
This change makes it compile and return the same value than the #undef one.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-04-21 13:26:47 +00:00
Peter Maydell
760e141613 softfloat: roundAndPackInt{32, 64}: Don't assume int32 is 32 bits
Fix code in roundAndPackInt32 that assumed that int32 was only
32 bits, by simply using int32_t instead. Fix the parallel bug
in roundAndPackInt64 as well, although that one is only theoretical
since it's unlikely that int64 will ever be more than 64 bits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-04-07 11:15:55 +00:00
Peter Maydell
b3a6a2e041 softfloat: float*_to_int32_round_to_zero: don't assume int32 is 32 bits
Code in the float64_to_int32_round_to_zero() function was assuming
that int32 would not be wider than 32 bits; this meant it might
not correctly detect the overflow case. We take the simple approach
of using int32_t. Also fix equivalent issues in the functions
for other float sizes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-04-07 11:15:44 +00:00
Avi Kivity
3bf7e40ab9 softfloat: fix for C99
C99 appears to consider compound literals as non-constants, and complains
when they are used in static initializers.  Switch to ordinary initializer
syntax.

Signed-off-by: Avi Kivity <avi@redhat.com>
Acked-by: Andreas Färber <afaerber@suse.de>
Reported-by: Andreas Färber <andreas.faerber@web.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-03-17 13:01:18 +00:00
Peter Maydell
369be8f618 softfloat: Implement fused multiply-add
Implement fused multiply-add as a softfloat primitive. This implements
"a+b*c" as a single step without any intermediate rounding; it is
specified in IEEE 754-2008 and implemented in a number of CPUs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2011-10-19 16:14:06 +00:00
Peter Maydell
2ac8bd03c5 softfloat: Reinstate accidentally disabled target-specific NaN handling
Include config.h in softfloat.c, so that the target specific ifdefs in
softfloat-specialize.h are evaluated correctly. This was accidentally
broken in commit 789ec7ce2 when config-target.h was removed from
softfloat.h, and means that most targets will have been returning the
wrong results for calculations involving NaNs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-10-01 06:19:07 +00:00
Andreas Färber
9f8d2a093f softfloat: Use uint32 consistently
Prepares for uint32 replacement.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-09-03 17:47:14 +00:00
Andreas Färber
38641f8f54 softfloat: Use uint16 consistently
Prepares for uint16 replacement.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-09-03 17:46:43 +00:00
Paolo Bonzini
789ec7ce20 softfloat: change default nan definitions to variables
Most definitions in softfloat.h are really target-independent, but the
file is not because it includes definitions of the default NaN values.
Change those to variables to allow including softfloat.h from files that
are not compiled per-target.  By making them const, the compiler is
allowed to optimize them into softfloat functions that use them.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-07-29 08:25:45 -05:00
Aurelien Jarno
587eabfafc softfloat: add float*_is_zero_or_denormal()
float*_is_zero_or_denormal() is available for float32, but not for
float64, floatx80 and float128. Fix that.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-06-03 16:07:53 +02:00
Aurelien Jarno
be22a9abc0 softfloat: always enable floatx80 and float128 support
Now that softfloat-native is gone, there is no real point on not always
enabling floatx80 and float128 support.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-06-03 16:07:51 +02:00
Aurelien Jarno
cf67c6bad5 softfloat-native: remove
Remove softfloat-native support, all targets are now using softfloat
instead.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-06-03 16:07:51 +02:00
Peter Maydell
e6afc87f80 softfloat: Add new flag for when denormal result is flushed to zero
Add a new float_flag_output_denormal which is set when the result
of a floating point operation would be denormal but is flushed to
zero because we are in flush_to_zero mode. This is necessary because
some architectures signal this condition as an underflow and others
signal it as an inexact result.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-05-23 22:39:35 +02:00
Aurelien Jarno
4cc5383f80 softfloat-native: add float*_is_any_nan() functions
Add float*_is_any_nan() functions to match the softfloat API.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:33 +02:00
Aurelien Jarno
d6882cf01f softfloat-native: fix float*_scalbn() functions
float*_scalbn() should be able to take a status parameter. Fix that.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:33 +02:00
Aurelien Jarno
326b9e98a3 softfloat: fix float*_scalnb() corner cases
float*_scalnb() were not taking into account all cases. This patch fixes
some corner cases:
- NaN values in input were not properly propagated and the invalid flag
  not correctly raised. Use propagateFloat*NaN() for that.
- NaN or infinite values in input of floatx80_scalnb() were not correctly
  detected due to a typo.
- The sum of exponent and n could overflow, leading to strange results.
  Additionally having int16 defined to int make that happening for a very
  small range of values. Fix that by saturating n to the maximum exponent
  range, and using an explicit wider type if needed.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:33 +02:00
Aurelien Jarno
f6714d365d softfloat: add floatx80_compare*() functions
Add floatx80_compare() and floatx80_compare_quiet() functions to match
the softfloat-native ones.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:32 +02:00
Aurelien Jarno
d2b1027d5f softfloat-native: add a few constant values
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:32 +02:00
Aurelien Jarno
c4b4c77a80 softfloat: add pi constants
Add a pi constant for float32, float64, floatx80. It will be used by
target-i386 and later by the trigonometric functions.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:32 +02:00
Aurelien Jarno
f3218a8df0 softfloat: add floatx80 constants
Add floatx80 constants similarly to float32 or float64.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:32 +02:00