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2016-09-15fpu: add mechanism to check for invalid long double formatsAndrew Dutcher1-0/+15
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>
2016-08-15softfloat: Fix warn about implicit conversion from int to int8_tPranith Kumar1-2/+2
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>
2016-07-12Clean up decorations and whitespace around header guardsMarkus Armbruster1-1/+1
Cleaned up with scripts/clean-header-guards.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-06-24softfloat: Implement run-time-configurable meaning of signaling NaN bitAleksandar Markovic1-20/+25
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>
2016-02-23include: Clean up includesPeter Maydell1-3/+0
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. NB: If this commit breaks compilation for your out-of-tree patchseries or fork, then you need to make sure you add #include "qemu/osdep.h" to any new .c files that you have. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-19fpu: Remove use of int_fast16_t in conversions to int16Peter Maydell1-8/+8
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
2016-01-22fpu: Replace uint8 typedef with uint8_tPeter Maydell1-9/+4
Replace the uint8 softfloat-specific typedef with uint8_t. This change was made with find include hw fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\buint8\b/uint8_t/g' together with manual removal of the typedef definition and manual fixing of more erroneous uses found via test compilation. It turns out that the only code using this type is an accidental use where uint8_t was intended anyway... 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: 1452603315-27030-7-git-send-email-peter.maydell@linaro.org
2016-01-22fpu: Replace int8 typedef with int8_tPeter Maydell1-2/+1
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
2016-01-22fpu: Replace uint32 typedef with uint32_tPeter Maydell1-6/+4
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
2016-01-22fpu: Replace int32 typedef with int32_tPeter Maydell1-9/+9
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
2016-01-22fpu: Replace uint64 typedef with uint64_tPeter Maydell1-5/+4
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
2016-01-22fpu: Replace int64 typedef with int64_tPeter Maydell1-9/+8
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
2015-02-06softfloat: expand out STATUS macroPeter Maydell1-16/+14
Expand out and remove the STATUS macro. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2015-02-06softfloat: expand out STATUS_VARPeter Maydell1-5/+4
Expand out and remove the STATUS_VAR macro. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2015-02-06softfloat: Expand out the STATUS_PARAM macroPeter Maydell1-166/+166
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>
2015-01-29softfloat: Clarify license statusPeter Maydell1-1/+47
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
2015-01-29softfloat: Revert and reimplement remaining portions of 75d62a5856 and ↵Peter Maydell1-2/+2
3430b0be36f Revert the remaining portions of commits 75d62a5856 and 3430b0be36f 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
2015-01-29softfloat: Apply patch corresponding to rebasing to softfloat-2aPeter Maydell1-17/+15
This commit applies the changes to master which correspond to replacing commit 158142c2c2df with a set of changes made by: * taking the SoftFloat-2a release * mechanically transforming the block comment style * reapplying Fabrice's original changes from 158142c2c2df This commit was created by: diff -u 158142c2c2df 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
2014-10-14softfloat: add functions corresponding to IEEE-2008 min/maxNumMagLeon Alrae1-0/+4
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>
2014-06-23fpu: softfloat: drop INLINE macroLuiz Capitulino1-50/+49
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>
2014-04-08softfloat: Introduce float32_to_uint64_round_to_zeroTom Musta1-0/+1
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>
2014-03-17softfloat: export squash_input_denormal functionsAlex Bennée1-0/+7
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
2014-02-20softfloat: Support halving the result of muladd operationPeter Maydell1-0/+3
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>
2014-01-08softfloat: Add support for ties-away roundingPeter Maydell1-1/+2
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>
2014-01-08softfloat: Add float16 <=> float64 conversion functionsPeter Maydell1-0/+2
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>
2014-01-08softfloat: Provide complete set of accessors for fp statePeter Maydell1-3/+36
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>
2014-01-08softfloat: Add float32_to_uint64()Tom Musta1-0/+1
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>
2014-01-08softfloat: Make the int-to-float functions take exact-width typesPeter Maydell1-13/+13
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>
2014-01-08softfloat: Add 16 bit integer to float conversionsPeter Maydell1-0/+21
Add the float to 16 bit integer conversion routines. These can be trivially implemented in terms of the int32_to_float* routines, but providing them makes our API more symmetrical and can simplify callers. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-01-08softfloat: Add float to 16bit integer conversions.Will Newton1-0/+4
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>
2013-12-10softfloat: Add minNum() and maxNum() functions to softfloat.Will Newton1-0/+4
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>
2013-01-05softfloat: Implement uint64_to_float128Richard Henderson1-0/+3
Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-12-19fpu: move public header file to include/fpuPaolo Bonzini1-0/+638
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>