dolysis
/
snappy
mirror of https://github.com/google/snappy.git
3
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Move the comment about non-overlap requirement from the implementation to the 

contract of `MemCopy64()`, and clarify that it applies to `size`, not to 64.

PiperOrigin-RevId: 453920284
This commit is contained in:
Marcin Kowalczyk 2022-06-09 14:28:22 +00:00 committed by Victor Costan
parent d261d2766f
commit 44caf79086
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
snappy.cc
View File

@ -985,7 +985,8 @@ inline bool Copy64BytesWithPatternExtension(ptrdiff_t dst, size_t offset) {
// Copies between size bytes and 64 bytes from src to dest. size cannot exceed
// 64. More than size bytes, but never exceeding 64, might be copied if doing
// so gives better performance.
// so gives better performance. [src, src + size) must not overlap with
// [dst, dst + size), but [src, src + 64) may overlap with [dst, dst + 64).
void MemCopy64(char* dst, const void* src, size_t size) {
// Always copy this many bytes, test if we need to copy more.
constexpr int kShortMemCopy = 32;
@ -994,7 +995,6 @@ void MemCopy64(char* dst, const void* src, size_t size) {
constexpr int kLongMemCopy = 64;
assert(size <= kLongMemCopy);
// [src, src + size) must not overlap with [dst, dst + size)
assert(std::less_equal<const void*>()(static_cast<const char*>(src) + size,
dst) ||
std::less_equal<const void*>()(dst + size, src));