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2025-10-05[libc][math] Refactor exp2 implementation to header-only in ↵Muhammad Bassiouni
src/__support/math folder. (#161297) Part of #147386 in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450
2025-03-11[libc] Provide more fine-grained control of FMA instruction for ARM targets. ↵lntue
(#130700)
2025-03-05[libc][math] Add skip accurate pass option for exp*, log*, and powf ↵lntue
functions. (#129831)
2024-10-26[libc][math] Add tests and fix some issues with FTZ/DAZ modes. (#113744)lntue
2024-07-12[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98597)Petr Hosek
This is a part of #97655.
2024-07-12Revert "[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace ↵Mehdi Amini
declaration" (#98593) Reverts llvm/llvm-project#98075 bots are broken
2024-07-11[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98075)Petr Hosek
This is a part of #97655.
2024-03-20[libc][NFC] Move `Sign` type to separate header (#85930)Guillaume Chatelet
2024-02-16[reland][libc][NFC] Use user defined literals to build 128 and 256 bit ↵Guillaume Chatelet
constants (#81998) - #81835 - Fix for platforms where uint64_t is not available
2024-02-15Revert "[reland][libc][NFC] Use user defined literals to build 128 and 256 ↵Guillaume Chatelet
bit constants" (#81882) Reverts llvm/llvm-project#81835 This is breaking arm32 which does not support 64 bit types.
2024-02-15[reland][libc][NFC] Use user defined literals to build 128 and 256 bit ↵Guillaume Chatelet
constants (#81835) This is a reland of #81746
2024-02-14Revert "[libc][NFC] Use user defined literals to build 128 and 256 bit ↵Guillaume Chatelet
constants." (#81771) Reverts llvm/llvm-project#81746
2024-02-14[libc][NFC] Use user defined literals to build 128 and 256 bit constants. ↵Guillaume Chatelet
(#81746)
2024-01-30[libc][NFC] Rename `FPBits` nan functions (#79998)Guillaume Chatelet
- [libc][NFC] Rename FPBits nan functions - rename build_signaling_nan in signaling_nan - rename build_quiet_nan to quiet_nan
2024-01-23[reland][libc] Remove unnecessary `FPBits` functions and properties (#79128)Guillaume Chatelet
- reland #79113 - Fix aarch64 RISC-V build
2024-01-23Revert "[libc] Remove unnecessary `FPBits` functions and properties" (#79118)Guillaume Chatelet
Reverts llvm/llvm-project#79113 It broke aarch64 build bot machines.
2024-01-23[libc] Remove unnecessary `FPBits` functions and properties (#79113)Guillaume Chatelet
This patch reduces the surface of `FPBits`.
2024-01-18[libc][NFC] Use the Sign type for DyadicFloat (#78577)Guillaume Chatelet
2024-01-18[libc][NFC] Introduce a Sign type for FPBits (#78500)Guillaume Chatelet
Another patch is needed to cover `DyadicFloat` and `NormalFloat` constructors.
2024-01-04[libc][NFC] Simplify `FPBits` (#76835)Guillaume Chatelet
This patch reduces the scope of `FPBits` exported variables and functions. It also moves storage up into `FPRep` and tries to make the default and specialized versions of `FPBits` more uniform. The next step is to move the specialization from `FPBits` to `FPRep` so we can manipulate floating point representations through `FPType` alone - that is - independently from the host architecture.
2023-12-15[libc][NFC] Rename `MANTISSA_WIDTH` in `FRACTION_LEN` (#75489)Guillaume Chatelet
This one might be a bit controversial since the terminology has been introduced from the start but I think `FRACTION_LEN` is a better name here. AFAICT it really is "the number of bits after the decimal dot when the number is in normal form." `MANTISSA_WIDTH` is less precise as it's unclear whether we take the leading bit into account. This patch also renames most of the properties to use the `_LEN` suffix and fixes useless casts or variables.
2023-12-13Revert "[libc][NFC] Implement `FPBits` in terms of `FloatProperties` to ↵Guillaume Chatelet
reduce clutter" (#75304) Reverts llvm/llvm-project#75196 GCC complains about change of meaning for `FPBits` ``` /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-gcc-fullbuild-dbg/llvm-project/libc/src/__support/FPUtil/generic/FMod.h:188:9: error: declaration of ‘using FPBits = struct __llvm_libc_18_0_0_git::fputil::FPBits<T>’ changes meaning of ‘FPBits’ [-fpermissive] 188 | using FPBits = FPBits<T>; | ^~~~~~ ``` I'll reland with a different name.
2023-12-13[libc][NFC] Implement `FPBits` in terms of `FloatProperties` to reduce ↵Guillaume Chatelet
clutter (#75196) Also make type naming consistent: - `UIntType` instead of `intU_t` - `FPBits` instead of `FPBits_t`, `FPB`
2023-12-08[libc][NFC] Clean up conversion warnings in math function implementations. ↵lntue
(#74697)
2023-09-26[libc] Mass replace enclosing namespace (#67032)Guillaume Chatelet
This is step 4 of https://discourse.llvm.org/t/rfc-customizable-namespace-to-allow-testing-the-libc-when-the-system-libc-is-also-llvms-libc/73079
2023-05-23[libc][math] Implement double precision log2 function correctly rounded to ↵Tue Ly
all rounding modes. Implement double precision log2 function correctly rounded to all rounding modes. See https://reviews.llvm.org/D150014 for a more detail description of the algorithm. **Performance** - For `0.5 <= x <= 2`, the fast pass hitting rate is about 99.91%. - Reciprocal throughput from CORE-MATH's perf tool on Ryzen 5900X: ``` $ ./perf.sh log2 GNU libc version: 2.35 GNU libc release: stable -- CORE-MATH reciprocal throughput -- with FMA [####################] 100 % Ntrial = 20 ; Min = 15.458 + 0.204 clc/call; Median-Min = 0.224 clc/call; Max = 15.867 clc/call; -- CORE-MATH reciprocal throughput -- without FMA (-march=x86-64-v2) [####################] 100 % Ntrial = 20 ; Min = 23.711 + 0.524 clc/call; Median-Min = 0.443 clc/call; Max = 25.307 clc/call; -- System LIBC reciprocal throughput -- [####################] 100 % Ntrial = 20 ; Min = 14.807 + 0.199 clc/call; Median-Min = 0.211 clc/call; Max = 15.137 clc/call; -- LIBC reciprocal throughput -- with FMA [####################] 100 % Ntrial = 20 ; Min = 17.666 + 0.274 clc/call; Median-Min = 0.298 clc/call; Max = 18.531 clc/call; -- LIBC reciprocal throughput -- without FMA [####################] 100 % Ntrial = 20 ; Min = 26.534 + 0.418 clc/call; Median-Min = 0.462 clc/call; Max = 27.327 clc/call; ``` - Latency from CORE-MATH's perf tool on Ryzen 5900X: ``` $ ./perf.sh log2 --latency GNU libc version: 2.35 GNU libc release: stable -- CORE-MATH latency -- with FMA [####################] 100 % Ntrial = 20 ; Min = 46.048 + 1.643 clc/call; Median-Min = 1.694 clc/call; Max = 48.018 clc/call; -- CORE-MATH latency -- without FMA (-march=x86-64-v2) [####################] 100 % Ntrial = 20 ; Min = 62.333 + 0.138 clc/call; Median-Min = 0.119 clc/call; Max = 62.583 clc/call; -- System LIBC latency -- [####################] 100 % Ntrial = 20 ; Min = 45.206 + 1.503 clc/call; Median-Min = 1.467 clc/call; Max = 47.229 clc/call; -- LIBC latency -- with FMA [####################] 100 % Ntrial = 20 ; Min = 43.042 + 0.454 clc/call; Median-Min = 0.484 clc/call; Max = 43.912 clc/call; -- LIBC latency -- without FMA [####################] 100 % Ntrial = 20 ; Min = 57.016 + 1.636 clc/call; Median-Min = 1.655 clc/call; Max = 58.816 clc/call; ``` - Accurate pass latency: ``` $ ./perf.sh log2 --latency --simple_stat GNU libc version: 2.35 GNU libc release: stable -- CORE-MATH latency -- with FMA 177.632 -- CORE-MATH latency -- without FMA (-march=x86-64-v2) 231.332 -- LIBC latency -- with FMA 459.751 -- LIBC latency -- without FMA 463.850 ``` Reviewed By: zimmermann6 Differential Revision: https://reviews.llvm.org/D150374
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