From 4fd9a1ec5077daac14eeee05df931d658ec0b7b8 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Thu, 19 Nov 2020 11:40:19 -0800 Subject: Export of internal Abseil changes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit -- 03700706d80f0939e2b5b8c02a326f045b643730 by Abseil Team : Reduced latency and code-size of some InlinedVector methods: 1. Simpler fast path for push_back/emplace_back. 2. Do not inline slow path of push-back/emplace_back. 3. Simplify resize implementation. Performance: A simple benchmark that does the following per iteration: ``` push_back on an InlinedVector push_back on an InlinedVector ``` Sees iteration time go from 4.3ns to 2.8ns and code size shrink from 1129 bytes to 175 bytes. PiperOrigin-RevId: 343335635 -- 16f74277a9e8bf228c164b053da8b8098f76de62 by Derek Mauro : Internal change PiperOrigin-RevId: 343332753 -- 886b6d5d0244783d309e34f03c21710f411e3cb3 by Abseil Team : Optimize `Status::Status`: When creating a status, we currently create an empty struct first, then assign fields. This is suboptimal: https://screenshot.googleplex.com/5HqDuFBKUEqrVgy. Relevant Benchmarks: ``` BM_StatusCopyError_Deep/threads:1 26.9ns ±13% 21.2ns ±16% -21.46% (p=0.000 n=15+15) BM_StatusCopyError_Deep/threads:2 32.0ns ±30% 25.6ns ±37% -20.17% (p=0.004 n=15+14) BM_StatusCopyError_Deep/threads:4 37.4ns ±84% 30.6ns ±58% -18.26% (p=0.029 n=15+15) BM_StatusCopyError_Deep/threads:8 47.2ns ±33% 33.5ns ±56% -28.91% (p=0.000 n=15+14) ``` PiperOrigin-RevId: 343303312 -- 2f9d945654292e8e52cad410fa41dae794cff42c by Abseil Team : Set SOVERSION for the installed libraries PiperOrigin-RevId: 343287682 -- 600bbfffe91cfbdc60b43cdad5619258298d0b0d by Abseil Team : Fix a typo in a comment (than -> that) PiperOrigin-RevId: 343187724 -- 310c82cd97b3f1f0d1ee93a0ee2b0aee828b2a93 by Abseil Team : Simplify unaligned memory access functions. The #ifdef to produce calls to __sanitizer_unaligned_load16 etc were needed in past versions of this code, when we were lying to the compiler about the alignment of the loads/stores, by using a reinterpret_cast. However, a year ago, absl switched to simply use memcpy. Sanitizers support this correctly by default, nothing extra is required. PiperOrigin-RevId: 343159883 -- bdf6fcf99180c371fda6ba8af82fd44656e372fa by Gennadiy Rozental : Migrate usage flags to global variables instead of modeling them as Abseil Flags. Also introduce new semantic for --help=substring command line argument. PiperOrigin-RevId: 343019883 GitOrigin-RevId: 03700706d80f0939e2b5b8c02a326f045b643730 Change-Id: I4ad40dfa9606f8b8bfb2d91fd09e327105311bfb --- absl/base/internal/unaligned_access.h | 66 ----------------------------------- 1 file changed, 66 deletions(-) (limited to 'absl/base/internal/unaligned_access.h') diff --git a/absl/base/internal/unaligned_access.h b/absl/base/internal/unaligned_access.h index 080c197c..093dd9b4 100644 --- a/absl/base/internal/unaligned_access.h +++ b/absl/base/internal/unaligned_access.h @@ -31,70 +31,6 @@ // The unaligned API is C++ only. The declarations use C++ features // (namespaces, inline) which are absent or incompatible in C. #if defined(__cplusplus) - -#if defined(ABSL_HAVE_ADDRESS_SANITIZER) || \ - defined(ABSL_HAVE_THREAD_SANITIZER) || defined(ABSL_HAVE_MEMORY_SANITIZER) -// Consider we have an unaligned load/store of 4 bytes from address 0x...05. -// AddressSanitizer will treat it as a 3-byte access to the range 05:07 and -// will miss a bug if 08 is the first unaddressable byte. -// ThreadSanitizer will also treat this as a 3-byte access to 05:07 and will -// miss a race between this access and some other accesses to 08. -// MemorySanitizer will correctly propagate the shadow on unaligned stores -// and correctly report bugs on unaligned loads, but it may not properly -// update and report the origin of the uninitialized memory. -// For all three tools, replacing an unaligned access with a tool-specific -// callback solves the problem. - -#include - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace base_internal { - -inline uint16_t UnalignedLoad16(const void *p) { - return __sanitizer_unaligned_load16(p); -} - -inline uint32_t UnalignedLoad32(const void *p) { - return __sanitizer_unaligned_load32(p); -} - -inline uint64_t UnalignedLoad64(const void *p) { - return __sanitizer_unaligned_load64(p); -} - -inline void UnalignedStore16(void *p, uint16_t v) { - __sanitizer_unaligned_store16(p, v); -} - -inline void UnalignedStore32(void *p, uint32_t v) { - __sanitizer_unaligned_store32(p, v); -} - -inline void UnalignedStore64(void *p, uint64_t v) { - __sanitizer_unaligned_store64(p, v); -} - -} // namespace base_internal -ABSL_NAMESPACE_END -} // namespace absl - -#define ABSL_INTERNAL_UNALIGNED_LOAD16(_p) \ - (absl::base_internal::UnalignedLoad16(_p)) -#define ABSL_INTERNAL_UNALIGNED_LOAD32(_p) \ - (absl::base_internal::UnalignedLoad32(_p)) -#define ABSL_INTERNAL_UNALIGNED_LOAD64(_p) \ - (absl::base_internal::UnalignedLoad64(_p)) - -#define ABSL_INTERNAL_UNALIGNED_STORE16(_p, _val) \ - (absl::base_internal::UnalignedStore16(_p, _val)) -#define ABSL_INTERNAL_UNALIGNED_STORE32(_p, _val) \ - (absl::base_internal::UnalignedStore32(_p, _val)) -#define ABSL_INTERNAL_UNALIGNED_STORE64(_p, _val) \ - (absl::base_internal::UnalignedStore64(_p, _val)) - -#else - namespace absl { ABSL_NAMESPACE_BEGIN namespace base_internal { @@ -141,8 +77,6 @@ ABSL_NAMESPACE_END #define ABSL_INTERNAL_UNALIGNED_STORE64(_p, _val) \ (absl::base_internal::UnalignedStore64(_p, _val)) -#endif - #endif // defined(__cplusplus), end of unaligned API #endif // ABSL_BASE_INTERNAL_UNALIGNED_ACCESS_H_ -- cgit v1.2.3