llvm-project.git/libc/src/math/generic/exp2f.cpp, branch main

[libc][math] Refactor exp2f implementation to header-only in src/__support/math folder. (#161992)

2025-10-06T18:23:44+00:00

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

[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98597)

2024-07-12T16:28:41+00:00

This is a part of #97655.

Revert "[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration" (#98593)

2024-07-12T07:12:13+00:00

Reverts llvm/llvm-project#98075

bots are broken

[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98075)

2024-07-11T19:35:22+00:00

This is a part of #97655.

[libc][math] Implement powf function correctly rounded to all rounding modes. (#71188)

2023-11-06T21:54:25+00:00

We compute `pow(x, y)` using the formula
```
  pow(x, y) = x^y = 2^(y * log2(x))
```
We follow similar steps as in `log2f(x)` and `exp2f(x)`, by breaking
down into `hi + mid + lo` parts, in which `hi` parts are computed using
the exponent field directly, `mid` parts will use look-up tables, and
`lo` parts are approximated by polynomials.

We add some speedup for common use-cases:
```
  pow(2, y) = exp2(y)
  pow(10, y) = exp10(y)
  pow(x, 2) = x * x
  pow(x, 1/2) = sqrt(x)
  pow(x, -1/2) = rsqrt(x) - to be added
```

[libc] Mass replace enclosing namespace (#67032)

2023-09-26T09:45:04+00:00

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

[libc] Fix final conversion warnings

2023-08-09T17:24:03+00:00

This patch fixes the floating point conversion warnings found with
`-Wconversion` and `-Wno-sign-conversion`. These were the last warnings
I found, meaning that once this lands https://reviews.llvm.org/D156630
should be unblocked.

Reviewed By: mcgrathr, lntue

Differential Revision: https://reviews.llvm.org/D157449

[libc][math] Improve exp2f performance.

2023-06-20T13:34:20+00:00

Re-organize special cases and add a special case when `|x| < 2^-5`.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153134

[libc] Add platform independent floating point rounding mode checks.

2023-06-12T13:36:41+00:00

Many math functions need to check for floating point rounding modes to
return correct values.  Currently most of them use the internal implementation
of `fegetround`, which is platform-dependent and blocking math functions to be
enabled on platforms with unimplemented `fegetround`.  In this change, we add
platform independent rounding mode checks and switching math functions to use
them instead. https://github.com/llvm/llvm-project/issues/63016

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152280

[libc] Fix undefined behavior of left shifting signed integer in exp2f.cpp.

2023-06-07T05:15:18+00:00

Fix undefined behavior of left shifting signed integer in exp2f.cpp.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152336