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| author | bors <bors@rust-lang.org> | 2021-10-04 12:49:57 +0000 |
|---|---|---|
| committer | bors <bors@rust-lang.org> | 2021-10-04 12:49:57 +0000 |
| commit | 175b8db73bfd078b4bcd3c28c8d6f51d5895ebf3 (patch) | |
| tree | be5ea44b10f6f928aa881c468aa6a602a2c192ab /compiler/rustc_codegen_llvm/src/llvm_util.rs | |
| parent | a4797664ba9c7d71e586122853858eeb6c153bb9 (diff) | |
| parent | 5e1428e18be47b48c5c94d6e067d24f44074cd32 (diff) | |
| download | rust-175b8db73bfd078b4bcd3c28c8d6f51d5895ebf3.tar.gz rust-175b8db73bfd078b4bcd3c28c8d6f51d5895ebf3.zip | |
Auto merge of #88834 - the8472:char-count, r=joshtriplett
optimize str::from_utf8() validation when slice contains multibyte chars and str.chars().count() in all cases The change shows small but consistent improvements across several x86 target feature levels. I also tried to optimize counting with `slice.as_chunks` but that yielded more inconsistent results, bigger improvements for some optimization levels, lesser ones in others. ``` old, -O2, x86-64 test str::str_char_count_emoji ... bench: 1,924 ns/iter (+/- 26) test str::str_char_count_lorem ... bench: 879 ns/iter (+/- 12) test str::str_char_count_lorem_short ... bench: 5 ns/iter (+/- 0) new, -O2, x86-64 test str::str_char_count_emoji ... bench: 1,878 ns/iter (+/- 21) test str::str_char_count_lorem ... bench: 851 ns/iter (+/- 11) test str::str_char_count_lorem_short ... bench: 4 ns/iter (+/- 0) old, -O2, x86-64-v2 test str::str_char_count_emoji ... bench: 1,477 ns/iter (+/- 46) test str::str_char_count_lorem ... bench: 675 ns/iter (+/- 15) test str::str_char_count_lorem_short ... bench: 5 ns/iter (+/- 0) new, -O2, x86-64-v2 test str::str_char_count_emoji ... bench: 1,323 ns/iter (+/- 39) test str::str_char_count_lorem ... bench: 593 ns/iter (+/- 18) test str::str_char_count_lorem_short ... bench: 4 ns/iter (+/- 0) old, -O2, x86-64-v3 test str::str_char_count_emoji ... bench: 748 ns/iter (+/- 7) test str::str_char_count_lorem ... bench: 348 ns/iter (+/- 2) test str::str_char_count_lorem_short ... bench: 5 ns/iter (+/- 0) new, -O2, x86-64-v3 test str::str_char_count_emoji ... bench: 650 ns/iter (+/- 4) test str::str_char_count_lorem ... bench: 301 ns/iter (+/- 1) test str::str_char_count_lorem_short ... bench: 5 ns/iter (+/- 0) ``` and for the multibyte-char string validation: ``` old, -O2, x86-64 test str::str_validate_emoji ... bench: 4,606 ns/iter (+/- 64) new, -O2, x86-64 test str::str_validate_emoji ... bench: 3,837 ns/iter (+/- 60) ```
Diffstat (limited to 'compiler/rustc_codegen_llvm/src/llvm_util.rs')
0 files changed, 0 insertions, 0 deletions