[libc] clean up string_utils memory functions

The string_utils.h file previously included both memcpy and bzero. There
were no uses of bzero, and only one use of memcpy which was replaced
with __builtin_memcpy.

Author: michaelrj-google

libc/src/string/CMakeLists.txt

@@ -15,10 +15,7 @@ add_header_library(
   HDRS
     string_utils.h
   DEPENDS
-    .memory_utils.inline_bzero
-    .memory_utils.inline_memcpy
     libc.hdr.types.size_t
-    libc.include.stdlib
     libc.src.__support.CPP.bitset
     libc.src.__support.CPP.type_traits
     libc.src.__support.common

libc/src/string/string_utils.h

@@ -19,8 +19,6 @@
 #include "src/__support/CPP/type_traits.h" // cpp::is_same_v
 #include "src/__support/macros/config.h"
 #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
-#include "src/string/memory_utils/inline_bzero.h"
-#include "src/string/memory_utils/inline_memcpy.h"
 
 namespace LIBC_NAMESPACE_DECL {
 namespace internal {
@@ -220,7 +218,7 @@ LIBC_INLINE size_t strlcpy(char *__restrict dst, const char *__restrict src,
   if (!size)
     return len;
   size_t n = len < size - 1 ? len : size - 1;
-  inline_memcpy(dst, src, n);
+  __builtin_memcpy(dst, src, n);
   dst[n] = '\0';
   return len;
 }

utils/bazel/llvm-project-overlay/libc/BUILD.bazel

@@ -4190,7 +4190,6 @@ libc_support_library(
         ":__support_cpp_bitset",
         ":__support_macros_optimization",
         ":llvm_libc_types_size_t",
-        ":string_memory_utils",
         ":types_size_t",
     ],
 )