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[libc] Fix bug with __builtin_memcpy_inline
AbandonedPublic

Authored by gchatelet on Mar 20 2020, 2:40 AM.

Reviewers

abrachet

Summary

The bug comes from constant folding of __builtin_memcpy_inline sizie argument from a template parameter.

This revision is now accepted and ready to land.Mar 20 2020, 8:26 AM

I'm not submitting this for now since it will be fixed by D76504 eventually.

Dropping this since it should fix the original error with Clang 11

Path

Size

libc/

src/

string/

memory_utils/

3 lines

	Show All 28 Lines
	namespace __llvm_libc {			namespace __llvm_libc {

	// Copies `kBlockSize` bytes from `src` to `dst`.			// Copies `kBlockSize` bytes from `src` to `dst`.
	template <size_t kBlockSize>			template <size_t kBlockSize>
	static void Copy(char __restrict dst, const char __restrict src) {			static void Copy(char __restrict dst, const char __restrict src) {
	#if defined(LLVM_LIBC_MEMCPY_MONITOR)			#if defined(LLVM_LIBC_MEMCPY_MONITOR)
	LLVM_LIBC_MEMCPY_MONITOR(dst, src, kBlockSize);			LLVM_LIBC_MEMCPY_MONITOR(dst, src, kBlockSize);
	#elif defined(USE_BUILTIN_MEMCPY_INLINE)			#elif defined(USE_BUILTIN_MEMCPY_INLINE)
	__builtin_memcpy_inline(dst, src, kBlockSize);			constexpr size_t size = kBlockSize;
				__builtin_memcpy_inline(dst, src, size);
	#elif defined(USE_BUILTIN_MEMCPY)			#elif defined(USE_BUILTIN_MEMCPY)
	__builtin_memcpy(dst, src, kBlockSize);			__builtin_memcpy(dst, src, kBlockSize);
	#else			#else
	for (size_t i = 0; i < kBlockSize; ++i)			for (size_t i = 0; i < kBlockSize; ++i)
	dst[i] = src[i];			dst[i] = src[i];
	#endif			#endif
	}			}

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