main

GGitHub[libc++] Optimize num_get integral functions (#121795)

2bdd1357创建于 2025年11月24日历史提交

文件	最后提交记录	最后更新时间
__nop_locale_mgmt.h	[libc++] Remove the need for uselocale() (#120158) Instead of requiring uselocale() as part of the base locale API, define __locale_guard in the few places that need it directly, without making __locale_guard part of the base API. In practice, most mainstream platforms never used __locale_guard, so they also didn't need to define uselocale(), and after this patch they actually don't define it anymore.	1 年前
__posix_l_fallback.h	[libc++] Add missing iswctype_l in posix_l_fallbacks (#122484)	1 年前
__strtonum_fallback.h	[libc++] Optimize num_get integral functions (#121795) --------------------------------------------------- Benchmark old new --------------------------------------------------- BM_num_get<bool> 86.5 ns 32.3 ns BM_num_get<long> 82.1 ns 30.3 ns BM_num_get<long long> 85.2 ns 33.4 ns BM_num_get<unsigned short> 85.3 ns 31.2 ns BM_num_get<unsigned int> 84.2 ns 31.1 ns BM_num_get<unsigned long> 83.6 ns 31.9 ns BM_num_get<unsigned long long> 87.7 ns 31.5 ns BM_num_get<float> 116 ns 114 ns BM_num_get<double> 114 ns 114 ns BM_num_get<long double> 113 ns 114 ns BM_num_get<void*> 151 ns 144 ns This patch applies multiple optimizations: - Stages two and three of do_get are merged and a custom integer parser has been implemented This avoids allocations, removes the need for strto{,u}ll and avoids __stage2_int_loop (avoiding extra writes to memory) - std::find has been replaced with __atoms_offset, which uses vector instructions to look for a character Fixes #158100 Fixes #158102	8 个月前