[libc-commits] [libc] [libc] Change the GPU to use builtin memory functions (PR #68003)

[Guillaume Chatelet via libc-commits]

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@@ -0,0 +1,57 @@
+//===-- Trivial builtin implementations  ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_GENERIC_BUILTIN_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_GENERIC_BUILTIN_H
+
+#include "src/__support/macros/config.h"       // LIBC_INLINE
+#include "src/__support/macros/optimization.h" // LIBC_LOOP_NOUNROLL
+#include "src/string/memory_utils/utils.h"     // Ptr, CPtr
+
+#include <stddef.h> // size_t
+
+namespace LIBC_NAMESPACE {
+
+static_assert(LIBC_HAS_BUILTIN(__builtin_memcpy), "Builtin not defined");
+static_assert(LIBC_HAS_BUILTIN(__builtin_memset), "Builtin not defined");
+static_assert(LIBC_HAS_BUILTIN(__builtin_memmove), "Builtin not defined");
+static_assert(LIBC_HAS_BUILTIN(__builtin_bcmp), "Builtin not defined");
+
+[[maybe_unused]] LIBC_INLINE void
+inline_memcpy_builtin(Ptr dst, CPtr src, size_t count, size_t offset = 0) {
+  __builtin_memcpy(dst + offset, src + offset, count);
+}
+
+[[maybe_unused]] LIBC_INLINE void inline_memmove_builtin(Ptr dst, CPtr src,
+                                                         size_t count) {
+  __builtin_memmove(dst, src, count);
+}
+
+[[maybe_unused]] LIBC_INLINE static void
+inline_memset_builtin(Ptr dst, uint8_t value, size_t count, size_t offset = 0) {
+  __builtin_memset(dst + offset, value, count);
+}
+
+[[maybe_unused]] LIBC_INLINE BcmpReturnType
+inline_bcmp_builtin(CPtr p1, CPtr p2, size_t count, size_t offset = 0) {
+  return __builtin_bcmp(p1 + offset, p2 + offset, count)
+             ? BcmpReturnType::NONZERO()
----------------
gchatelet wrote:

We can trust `__builtin_bcmp` to return the correct value here no need for the ternary operator.

https://github.com/llvm/llvm-project/pull/68003