Commit Graph

180 Commits

Author SHA1 Message Date
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