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2023-09-16fpu: Handle m68k extended precision denormals properlyRichard Henderson
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>
2023-09-16fpu: Add conversions between bfloat16 and [u]int8LIU Zhiwei
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>
2023-07-01fpu: Add float64_to_int{32,64}_moduloRichard Henderson
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>
2023-06-26softfloat: use QEMU_FLATTEN to avoid mistaken isra inliningAlex Bennée
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>
2023-05-05softfloat: Fix the incorrect computation in float32_exp2Shivaprasad G Bhat
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>
2022-08-31fpu: Add rebias bool, value and operationLucas Mateus Castro (alqotel)
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>
2022-04-26softfloat: Use FloatRelation for fracN_cmpRichard Henderson
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>
2022-04-26softfloat: Fix declaration of partsN_compareRichard Henderson
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>
2022-04-20softfloat: add float128_to_int128Matheus Ferst
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>
2022-04-20softfloat: add float128_to_uint128Matheus Ferst
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>
2022-04-20softfloat: add int128_to_float128Matheus Ferst
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>
2022-04-20softfloat: add uint128_to_float128Matheus Ferst
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>
2021-12-17softfloat: Add float64r32 arithmetic routinesRichard Henderson
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>
2021-12-17softfloat: Add flag specific to signaling nansRichard Henderson
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>
2021-10-29softfloat: add APIs to handle alternative sNaN propagation for fmax/fminChih-Min Chao
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>
2021-06-15softfloat: Use _Generic instead of QEMU_GENERICRichard Henderson
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>
2021-06-13softfloat: Fix tp init in float32_exp2Richard Henderson
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>
2021-06-03softfloat: Use hard-float for {u}int64_to_float{32,64}Richard Henderson
For the normal case of no additional scaling, this reduces the profile contribution of int64_to_float64 to the testcase in the linked issue from 0.81% to 0.04%. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/134 Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert modrem operations to FloatPartsRichard Henderson
Rename to parts$N_modrem. This was the last use of a lot of the legacy infrastructure, so remove it as required. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move floatN_log2 to softfloat-parts.c.incRichard Henderson
Rename to parts$N_log2. Though this is partly a ruse, since I do not believe the code will succeed for float128 without work. Which is ok for now, because we do not need this for more than float32 and float64. Since berkeley-testfloat-3 doesn't support log2, compare float64_log2 vs the system log2. Fix the errors for inputs near 1.0: test: 3ff00000000000b0 +0x1.00000000000b0p+0 sf: 3d2fa00000000000 +0x1.fa00000000000p-45 libm: 3d2fbd422b1bd36f +0x1.fbd422b1bd36fp-45 Error in fraction: 32170028290927 ulp test: 3feec24f6770b100 +0x1.ec24f6770b100p-1 sf: bfad3740d13c9ec0 -0x1.d3740d13c9ec0p-5 libm: bfad3740d13c9e98 -0x1.d3740d13c9e98p-5 Error in fraction: 40 ulp Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert float32_exp2 to FloatPartsRichard Henderson
Keep the intermediate results in FloatParts instead of converting back and forth between float64. Use muladd instead of separate mul+add. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80 compare to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_scalbn to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80 to integer to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80 float conversions to FloatPartsRichard Henderson
This is the last use of commonNaNT and all of the routines that use it, so remove all of them for Werror. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert integer to floatx80 to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_round_to_int to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_round to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_sqrt to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_div to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_mul to FloatPartsRichard Henderson
Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Convert floatx80_add/sub to FloatPartsRichard Henderson
Since this is the first such, this includes all of the packing and unpacking routines as well. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Introduce Floatx80RoundPrecRichard Henderson
Use an enumeration instead of raw 32/64/80 values. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Reduce FloatFmtRichard Henderson
Remove frac_lsb, frac_lsbm1, roundeven_mask. Compute these from round_mask in parts$N_uncanon_normal. With floatx80, round_mask will not be tied to frac_shift. Everything else is easily computable. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Split out parts_uncanon_normalRichard Henderson
We will need to treat the non-normal cases of floatx80 specially, so split out the normal case that we can reuse. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move sqrt_float to softfloat-parts.c.incRichard Henderson
Rename to parts$N_sqrt. Reimplement float128_sqrt with FloatParts128. Reimplement with the inverse sqrt newton-raphson algorithm from musl. This is significantly faster than even the berkeley sqrt n-r algorithm, because it does not use division instructions, only multiplication. Ordinarily, changing algorithms at the same time as migrating code is a bad idea, but this is the only way I found that didn't break one of the routines at the same time. Tested-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move scalbn_decomposed to softfloat-parts.c.incRichard Henderson
Rename to parts$N_scalbn. Reimplement float128_scalbn with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move compare_floats to softfloat-parts.c.incRichard Henderson
Rename to parts$N_compare. Rename all of the intermediate functions to ftype_do_compare. Rename the hard-float functions to ftype_hs_compare. Convert float128 to FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Implement float128_(min|minnum|minnummag|max|maxnum|maxnummag)David Hildenbrand
The float128 implementation is straight-forward. Unfortuantely, we don't have any tests we can simply adjust/unlock. Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210517142739.38597-24-david@redhat.com> [rth: Update for changed parts_minmax return value] Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move minmax_flags to softfloat-parts.c.incRichard Henderson
Rename to parts$N_minmax. Combine 3 bool arguments to a bitmask. Introduce ftype_minmax functions as a common optimization point. Fold bfloat16 expansions into the same macro as the other types. Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move uint_to_float to softfloat-parts.c.incRichard Henderson
Rename to parts$N_uint_to_float. Reimplement uint64_to_float128 with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move int_to_float to softfloat-parts.c.incRichard Henderson
Rename to parts$N_sint_to_float. Reimplement int{32,64}_to_float128 with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03softfloat: Move round_to_uint_and_pack to softfloat-parts.c.incRichard Henderson
Rename to parts$N_float_to_uint. Reimplement float128_to_uint{32,64}{_round_to_zero} with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Move round_to_int_and_pack to softfloat-parts.c.incRichard Henderson
Rename to parts$N_float_to_sint. Reimplement float128_to_int{32,64}{_round_to_zero} with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Move round_to_int to softfloat-parts.c.incRichard Henderson
At the same time, convert to pointers, split out parts$N_round_to_int_normal, define a macro for parts_round_to_int using QEMU_GENERIC. This necessarily meant some rearrangement to the rount_to_{,u}int_and_pack routines, so go ahead and convert to parts_round_to_int_normal, which in turn allows cleaning up of the raised exception handling. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Convert float-to-float conversions with float128Richard Henderson
Introduce parts_float_to_float_widen and parts_float_to_float_narrow. Use them for float128_to_float{32,64} and float{32,64}_to_float128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Split float_to_floatRichard Henderson
Split out parts_float_to_ahp and parts_float_to_float. Convert to pointers. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Move div_floats to softfloat-parts.c.incRichard Henderson
Rename to parts$N_div. Implement float128_div with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Introduce sh[lr]_double primitivesRichard Henderson
Have x86_64 assembly for them, with a fallback. This avoids shuffling values through %cl in the x86 case. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16softfloat: Move muladd_floats to softfloat-parts.c.incRichard Henderson
Rename to parts$N_muladd. Implement float128_muladd with FloatParts128. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-22 13:46:34 +0000