fpu: Handle m68k extended precision denormals properly

Motorola treats denormals with explicit integer bit set as
having unbiased exponent 0, unlike Intel which treats it as
having unbiased exponent

fpu: Handle m68k extended precision denormals properly

Motorola treats denormals with explicit integer bit set as
having unbiased exponent 0, unlike Intel which treats it as
having unbiased exponent 1 (more like all other IEEE formats
that have no explicit integer bit).

Add a flag on FloatFmt to differentiate the behaviour.

Reported-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

fpu: Add conversions between bfloat16 and [u]int8

We missed these functions when upstreaming the bfloat16 support.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <202305310654

fpu: Add conversions between bfloat16 and [u]int8

We missed these functions when upstreaming the bfloat16 support.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <20230531065458.2082-1-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

fpu: Handle m68k extended precision denormals properly

Motorola treats denormals with explicit integer bit set as
having unbiased exponent 0, unlike Intel which treats it as
having unbiased exponent

fpu: Handle m68k extended precision denormals properly

Motorola treats denormals with explicit integer bit set as
having unbiased exponent 0, unlike Intel which treats it as
having unbiased exponent 1 (more like all other IEEE formats
that have no explicit integer bit).

Add a flag on FloatFmt to differentiate the behaviour.

Reported-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

fpu: Add conversions between bfloat16 and [u]int8

We missed these functions when upstreaming the bfloat16 support.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <202305310654

fpu: Add conversions between bfloat16 and [u]int8

We missed these functions when upstreaming the bfloat16 support.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <20230531065458.2082-1-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

fpu: Add float64_to_int{32,64}_modulo

Add versions of float64_to_int* which do not saturate the result.

Reviewed-by: Christoph Muellner <christoph.muellner@vrull.eu>
Tested-by: Christoph Muellner <

fpu: Add float64_to_int{32,64}_modulo

Add versions of float64_to_int* which do not saturate the result.

Reviewed-by: Christoph Muellner <christoph.muellner@vrull.eu>
Tested-by: Christoph Muellner <christoph.muellner@vrull.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230527141910.1885950-2-richard.henderson@linaro.org>

show more ...

softfloat: use QEMU_FLATTEN to avoid mistaken isra inlining

Balton discovered that asserts for the extract/deposit calls had a
significant impact on a lame benchmark on qemu-ppc. Replicating with:

softfloat: use QEMU_FLATTEN to avoid mistaken isra inlining

Balton discovered that asserts for the extract/deposit calls had a
significant impact on a lame benchmark on qemu-ppc. Replicating with:

./qemu-ppc64 ~/lsrc/tests/lame.git-svn/builds/ppc64/frontend/lame \
-h pts-trondheim-3.wav pts-trondheim-3.mp3

showed up the pack/unpack routines not eliding the assert checks as it
should have done causing them to prominently figure in the profile:

 11.44%  qemu-ppc64  qemu-ppc64               [.] unpack_raw64.isra.0
 11.03%  qemu-ppc64  qemu-ppc64               [.] parts64_uncanon_normal
  8.26%  qemu-ppc64  qemu-ppc64               [.] helper_compute_fprf_float64
  6.75%  qemu-ppc64  qemu-ppc64               [.] do_float_check_status
  5.34%  qemu-ppc64  qemu-ppc64               [.] parts64_muladd
  4.75%  qemu-ppc64  qemu-ppc64               [.] pack_raw64.isra.0
  4.38%  qemu-ppc64  qemu-ppc64               [.] parts64_canonicalize
  3.62%  qemu-ppc64  qemu-ppc64               [.] float64r32_round_pack_canonical

After this patch the same test runs 31 seconds faster with a profile
where the generated code dominates more:

+ 14.12% 0.00% qemu-ppc64 [unknown] [.] 0x0000004000619420
+ 13.30% 0.00% qemu-ppc64 [unknown] [.] 0x0000004000616850
+ 12.58% 12.19% qemu-ppc64 qemu-ppc64 [.] parts64_uncanon_normal
+ 10.62% 0.00% qemu-ppc64 [unknown] [.] 0x000000400061bf70
+ 9.91% 9.73% qemu-ppc64 qemu-ppc64 [.] helper_compute_fprf_float64
+ 7.84% 7.82% qemu-ppc64 qemu-ppc64 [.] do_float_check_status
+ 6.47% 5.78% qemu-ppc64 qemu-ppc64 [.] parts64_canonicalize.constprop.0
+ 6.46% 0.00% qemu-ppc64 [unknown] [.] 0x0000004000620130
+ 6.42% 0.00% qemu-ppc64 [unknown] [.] 0x0000004000619400
+ 6.17% 6.04% qemu-ppc64 qemu-ppc64 [.] parts64_muladd
+ 5.85% 0.00% qemu-ppc64 [unknown] [.] 0x00000040006167e0
+ 5.74% 0.00% qemu-ppc64 [unknown] [.] 0x0000b693fcffffd3
+ 5.45% 4.78% qemu-ppc64 qemu-ppc64 [.] float64r32_round_pack_canonical

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <ec9cfe5a-d5f2-466d-34dc-c35817e7e010@linaro.org>
[AJB: Patchified rth's suggestion]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: BALATON Zoltan <balaton@eik.bme.hu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-Id: <20230523131107.3680641-1-alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expecte

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expected output would be {1.071773, 4.000000, 4.000000, 0.500000}.
Instead, the function is computing {1.119102, 3.382044, 3.382044, -0.191022}

Looking at the code, the float32_exp2() attempts to do this

2 3 4 5 n
x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

But because of the typo it ends up doing

x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

This is because instead of the xnp which holds the numerator, parts_muladd
is using the xp which is just 'x'. Commit '572c4d862ff2' refactored this
function, and mistakenly used xp instead of xnp.

Cc: qemu-stable@nongnu.org
Fixes: 572c4d862ff2 "softfloat: Convert float32_exp2 to FloatParts"
Partially-Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1623
Reported-By: Luca Barbato (https://gitlab.com/lu-zero)
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Message-Id: <168304110865.537992.13059030916325018670.stgit@localhost.localdomain>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expecte

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expected output would be {1.071773, 4.000000, 4.000000, 0.500000}.
Instead, the function is computing {1.119102, 3.382044, 3.382044, -0.191022}

Looking at the code, the float32_exp2() attempts to do this

2 3 4 5 n
x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

But because of the typo it ends up doing

x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

This is because instead of the xnp which holds the numerator, parts_muladd
is using the xp which is just 'x'. Commit '572c4d862ff2' refactored this
function, and mistakenly used xp instead of xnp.

Cc: qemu-stable@nongnu.org
Fixes: 572c4d862ff2 "softfloat: Convert float32_exp2 to FloatParts"
Partially-Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1623
Reported-By: Luca Barbato (https://gitlab.com/lu-zero)
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Message-Id: <168304110865.537992.13059030916325018670.stgit@localhost.localdomain>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expecte

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expected output would be {1.071773, 4.000000, 4.000000, 0.500000}.
Instead, the function is computing {1.119102, 3.382044, 3.382044, -0.191022}

Looking at the code, the float32_exp2() attempts to do this

2 3 4 5 n
x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

But because of the typo it ends up doing

x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

This is because instead of the xnp which holds the numerator, parts_muladd
is using the xp which is just 'x'. Commit '572c4d862ff2' refactored this
function, and mistakenly used xp instead of xnp.

Cc: qemu-stable@nongnu.org
Fixes: 572c4d862ff2 "softfloat: Convert float32_exp2 to FloatParts"
Partially-Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1623
Reported-By: Luca Barbato (https://gitlab.com/lu-zero)
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Message-Id: <168304110865.537992.13059030916325018670.stgit@localhost.localdomain>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expecte

softfloat: Fix the incorrect computation in float32_exp2

The float32_exp2 function is computing wrong exponent of 2.

For example, with the following set of values {0.1, 2.0, 2.0, -1.0},
the expected output would be {1.071773, 4.000000, 4.000000, 0.500000}.
Instead, the function is computing {1.119102, 3.382044, 3.382044, -0.191022}

Looking at the code, the float32_exp2() attempts to do this

2 3 4 5 n
x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

But because of the typo it ends up doing

x x x x x x x
e = 1 + --- + --- + --- + --- + --- + ... + --- + ...
1! 2! 3! 4! 5! n!

This is because instead of the xnp which holds the numerator, parts_muladd
is using the xp which is just 'x'. Commit '572c4d862ff2' refactored this
function, and mistakenly used xp instead of xnp.

Cc: qemu-stable@nongnu.org
Fixes: 572c4d862ff2 "softfloat: Convert float32_exp2 to FloatParts"
Partially-Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1623
Reported-By: Luca Barbato (https://gitlab.com/lu-zero)
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Message-Id: <168304110865.537992.13059030916325018670.stgit@localhost.localdomain>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

fpu: Add rebias bool, value and operation

Added the possibility of recalculating a result if it overflows or
underflows, if the result overflow and the rebias bool is true then the
intermediate resu

fpu: Add rebias bool, value and operation

Added the possibility of recalculating a result if it overflows or
underflows, if the result overflow and the rebias bool is true then the
intermediate result should have 3/4 of the total range subtracted from
the exponent. The same for underflow but it should be added to the
exponent of the intermediate number instead.

Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220805141522.412864-2-lucas.araujo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

fpu: Add rebias bool, value and operation

Added the possibility of recalculating a result if it overflows or
underflows, if the result overflow and the rebias bool is true then the
intermediate resu

fpu: Add rebias bool, value and operation

Added the possibility of recalculating a result if it overflows or
underflows, if the result overflow and the rebias bool is true then the
intermediate result should have 3/4 of the total range subtracted from
the exponent. The same for underflow but it should be added to the
exponent of the intermediate number instead.

Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220805141522.412864-2-lucas.araujo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

fpu: Add rebias bool, value and operation

Added the possibility of recalculating a result if it overflows or
underflows, if the result overflow and the rebias bool is true then the
intermediate resu

fpu: Add rebias bool, value and operation

Added the possibility of recalculating a result if it overflows or
underflows, if the result overflow and the rebias bool is true then the
intermediate result should have 3/4 of the total range subtracted from
the exponent. The same for underflow but it should be added to the
exponent of the intermediate number instead.

Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220805141522.412864-2-lucas.araujo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

softfloat: Use FloatRelation for fracN_cmp

Since the caller, partsN_compare, is now exclusively
using FloatRelation, it's clearer to use it here too.

Signed-off-by: Richard Henderson <richard.hende

softfloat: Use FloatRelation for fracN_cmp

Since the caller, partsN_compare, is now exclusively
using FloatRelation, it's clearer to use it here too.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220401132240.79730-4-richard.henderson@linaro.org>

show more ...

softfloat: Fix declaration of partsN_compare

The declaration used 'int', while the definition used 'FloatRelation'.
This should have resulted in a compiler error, but mysteriously didn't.

Signed-of

softfloat: Fix declaration of partsN_compare

The declaration used 'int', while the definition used 'FloatRelation'.
This should have resulted in a compiler error, but mysteriously didn't.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220401132240.79730-2-richard.henderson@linaro.org>

show more ...

softfloat: add float128_to_int128

Implements float128_to_int128 based on parts_float_to_int logic.

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richa

softfloat: add float128_to_int128

Implements float128_to_int128 based on parts_float_to_int logic.

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220330175932.6995-7-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

softfloat: add float128_to_uint128

Implements float128_to_uint128 based on parts_float_to_uint logic.

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <ri

softfloat: add float128_to_uint128

Implements float128_to_uint128 based on parts_float_to_uint logic.

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220330175932.6995-6-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

softfloat: add int128_to_float128

Based on parts_sint_to_float, implements int128_to_float128 to convert a
signed 128-bit value received through an Int128 argument.

Signed-off-by: Matheus Ferst <ma

softfloat: add int128_to_float128

Based on parts_sint_to_float, implements int128_to_float128 to convert a
signed 128-bit value received through an Int128 argument.

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20220330175932.6995-5-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

softfloat: add uint128_to_float128

Based on parts_uint_to_float, implements uint128_to_float128 to convert
an unsigned 128-bit value received through an Int128 argument.

Signed-off-by: Matheus Fers

softfloat: add uint128_to_float128

Based on parts_uint_to_float, implements uint128_to_float128 to convert
an unsigned 128-bit value received through an Int128 argument.

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220330175932.6995-4-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

show more ...

softfloat: Add float64r32 arithmetic routines

These variants take a float64 as input, compute the result to
infinite precision (as we do with FloatParts), round the result
to the precision and dynam

softfloat: Add float64r32 arithmetic routines

These variants take a float64 as input, compute the result to
infinite precision (as we do with FloatParts), round the result
to the precision and dynamic range of float32, and then return
the result in the format of float64.

This is the operation PowerPC requires for its float32 operations.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-28-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

show more ...

softfloat: Add flag specific to signaling nans

PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message

softfloat: Add flag specific to signaling nans

PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-8-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

show more ...

softfloat: add APIs to handle alternative sNaN propagation for fmax/fmin

For "fmax/fmin ft0, ft1, ft2" and if one of the inputs is sNaN,

The original logic:
Return NaN and set invalid flag if

softfloat: add APIs to handle alternative sNaN propagation for fmax/fmin

For "fmax/fmin ft0, ft1, ft2" and if one of the inputs is sNaN,

The original logic:
Return NaN and set invalid flag if ft1 == sNaN || ft2 == sNan.

The alternative path:
Set invalid flag if ft1 == sNaN || ft2 == sNaN.
Return NaN only if ft1 == NaN && ft2 == NaN.

The IEEE 754 spec allows both implementation and some architecture such
as riscv choose different defintions in two spec versions.
(riscv-spec-v2.2 use original version, riscv-spec-20191213 changes to
alternative)

Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211021160847.2748577-2-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

show more ...

softfloat: Use _Generic instead of QEMU_GENERIC

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redh

softfloat: Use _Generic instead of QEMU_GENERIC

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210614233143.1221879-3-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

show more ...

softfloat: Use _Generic instead of QEMU_GENERIC

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@lina

softfloat: Use _Generic instead of QEMU_GENERIC

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210614233143.1221879-3-richard.henderson@linaro.org>

show more ...

softfloat: Fix tp init in float32_exp2

Typo in the conversion to FloatParts64.

Fixes: 572c4d862ff2
Fixes: Coverity CID 1457457
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Review

softfloat: Fix tp init in float32_exp2

Typo in the conversion to FloatParts64.

Fixes: 572c4d862ff2
Fixes: Coverity CID 1457457
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210607223812.110596-1-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...