llvm-project.git/libc/fuzzing/__support, branch main

[libc] add an SVE implementation of strlen (#167259)

2025-11-11T00:15:34+00:00

This PR creates an SVE-based implementation for strlen by translating
from the AOR code in tree. Microbenchmark shows improvements against
NEON when N>=64. Although both implementations fall behind glibc by a
large margin,
this may be a good start point to explore SVE implementations.

Together with the PR:

1. Added two more tests of strlen with special nul symbols.
2. Added strlen's fuzzer and fix a typo in previous heap fuzzer.

```
=== strlen(16 bytes) ===
libc: 1.56115 ns/call, 9.54499 GiB/s
neon: 1.59393 ns/call, 9.34867 GiB/s
sve: 1.66097 ns/call, 8.97134 GiB/s

=== strlen(64 bytes) ===
libc: 2.06967 ns/call, 28.7991 GiB/s
neon: 2.59914 ns/call, 22.9325 GiB/s
sve: 2.58628 ns/call, 23.0465 GiB/s

=== strlen(256 bytes) ===
libc: 3.74165 ns/call, 63.7202 GiB/s
neon: 8.98243 ns/call, 26.5428 GiB/s
sve: 7.36426 ns/call, 32.3751 GiB/s

=== strlen(1024 bytes) ===
libc: 10.5327 ns/call, 90.5438 GiB/s
neon: 34.363 ns/call, 27.7529 GiB/s
sve: 26.9329 ns/call, 35.4092 GiB/s

=== strlen(4096 bytes) ===
libc: 37.7304 ns/call, 101.104 GiB/s
neon: 145.911 ns/call, 26.144 GiB/s
sve: 103.208 ns/call, 36.9612 GiB/s

=== strlen(1048576 bytes) ===
libc: 9623.4 ns/call, 101.478 GiB/s
neon: 36138.2 ns/call, 27.023 GiB/s
sve: 26605.6 ns/call, 36.7051 GiB/s
```

[libc] Add proxy header for ENTRY type. (#139746)

2025-05-13T18:07:21+00:00

https://github.com/llvm/llvm-project/issues/139561

[libc] Fix warnings for freelist_heap_test/fuzz (#136634)

2025-04-22T18:11:31+00:00

Fixes #122367

[libc][NFC] Strip all training whitespace and missing newlines (#124163)

2025-01-23T18:02:54+00:00

[libc] Exclude FreeListHeap test and fuzzer on GPU (#120137)

2024-12-16T21:28:42+00:00

FreeListHeap uses the _end symbol which conflicts with the _end symbol
defined by GPU start.cpp files so for now we exclude the test and the
fuzzer on GPU.

[libc] Breakup freelist_malloc into separate files (#119806)

2024-12-16T18:30:27+00:00

This better matches the structure we use for the rest of libc.

Reapply "[libc] Use best-fit binary trie to make malloc logarithmic (#117065)"

2024-11-21T23:26:24+00:00

This reverts commit 93b83642ee34d0092b94776728dad0117c2b72a1.

 - Correct riscv32 assumption about alignment (bit of a hack).
 - Fix test case where the largest_small and smallest sizes are the
   same.

Revert "[libc] Use best-fit binary trie to make malloc logarithmic (#117065)"

2024-11-21T19:56:05+00:00

This reverts commit b05600d96f46697e21f6b1b7ad901391326243a8.
riscv32 unit test still broken

Reapply "[libc] Use best-fit binary trie to make malloc logarithmic" (#117065)

2024-11-21T19:30:51+00:00

 - Fix assertion expressions.
 - Fix incorrect small size in freestore_test.
 - There may only be one small size for high alignment and small
   pointers (riscv32).
 - Don't rely on stack alignment in FreeList test.

Revert "[libc] Use best-fit binary trie to make malloc logarithmic" (#117065)

2024-11-20T22:00:07+00:00

Reverts llvm/llvm-project#106259

Unit tests break on AArch64.