[libc-commits] [libc] [libc] Add fuzzers for `memcpy` and `memset` (PR #90591)

[Guillaume Chatelet via libc-commits]

gchatelet wrote:

The last presubmit run is indeed running the tests
```
...
[4131/4223] Running unit test libc.test.src.string.memcpy_x86_64_opt_sw_prefetch_avx_test.__unit__
[ RUN      ] LlvmLibcMemcpyTest.SizeSweep
[       OK ] LlvmLibcMemcpyTest.SizeSweep (took 157 us)
[ RUN      ] LlvmLibcMemcpyTest.CheckAccess
[       OK ] LlvmLibcMemcpyTest.CheckAccess (took 98 us)
Ran 2 tests.  PASS: 2  FAIL: 0
...
```

https://github.com/llvm/llvm-project/pull/90591