[libc] Fix memcpy to adhere to qualified calls.

[PaulkaToast]

Summary

Switched to using the new memcpy implementation.

[gchatelet]

But wait for @abrachet and @sivachandra

[abrachet]

libc/src/string/strcpy.cpp

18

Should we wait for D77279 to use __llvm_libc::strlen?

[sivachandra]

This patch largely looks good, but I have a question inline.

libc/src/math/round_redirector.cpp

16

This comment is not quite the right thing to say. This is a redirector so the expectation is to call round from the system libc.

17

Redirected calls should not need NOLINT annotations. Calling into system libc is correct by design. What is failing without this NOLINT annotation?

libc/src/string/strcpy.cpp

18

Yes. Wait for D77279 and absorb the change here.

libc/test/src/string/CMakeLists.txt

14

Can you add a TODO (sivachandra) here and below to remove the redundant deps?

[PaulkaToast]

libc/src/math/round_redirector.cpp

17

You're right, redirectors do this by design. Removed comment and nolint.

libc/src/string/strcpy.cpp

18

Gotcha (:

libc/fuzzing/string/CMakeLists.txt

 add_libc_fuzzer(
   strcpy_fuzz
   SRCS
     strcpy_fuzz.cpp
   DEPENDS
     strcpy
+    memcpy
 )

libc/src/math/round_redirector.cpp

 //===----------------  Implementation of round redirector -----------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 // Include okay for this redirector.
 // NOLINTNEXTLINE(llvmlibc-restrict-system-libc-headers)
 #include <math.h>
 
 namespace __llvm_libc {
 
 double __round_redirector(double x) {
-  return ::round(x);
+  // Call system round since llvm-libc round is yet to be implemented.
+  return ::round(x); // LIBC-NOLINT
 }
 
 } // namespace __llvm_libc

libc/src/string/CMakeLists.txt

 add_entrypoint_object(
   strcpy
   SRCS
     strcpy.cpp
   HDRS
     strcpy.h
   DEPENDS
     string_h
+    memcpy
 )
 
 # ------------------------------------------------------------------------------
 # memcpy
 # ------------------------------------------------------------------------------
 
 # include the relevant architecture specific implementations
 if(${LIBC_TARGET_MACHINE} STREQUAL "x86_64")

libc/src/string/strcpy.cpp

 //===-------------------- Implementation of strcpy -----------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 #include "src/string/strcpy.h"
+#include "src/string/memcpy.h"
 
 #include "src/__support/common.h"
 
 namespace __llvm_libc {
 
 char *LLVM_LIBC_ENTRYPOINT(strcpy)(char *dest, const char *src) {
-  return reinterpret_cast<char *>(::memcpy(dest, src, ::strlen(src) + 1));
+  return reinterpret_cast<char *>(
+      __llvm_libc::memcpy(dest, src, ::strlen(src) + 1));
 }
 
 } // namespace __llvm_libc

libc/test/src/string/CMakeLists.txt

 add_libc_testsuite(libc_string_unittests)
 
 add_subdirectory(memory_utils)
 
 add_libc_unittest(
   strcat_test
   SUITE
     libc_string_unittests
   SRCS
     strcat_test.cpp
   DEPENDS
     strcat
     strcpy
+    memcpy
 )
 
 add_libc_unittest(
   strcpy_test
   SUITE
     libc_string_unittests
   SRCS
     strcpy_test.cpp
   DEPENDS
     strcpy
+    memcpy
 )
 
 # Tests all implementations of memcpy that can run on the host.
 get_property(memcpy_implementations GLOBAL PROPERTY memcpy_implementations)
 foreach(memcpy_config_name IN LISTS memcpy_implementations)
   get_target_property(require_cpu_features ${memcpy_config_name} REQUIRE_CPU_FEATURES)
   host_supports(can_run "${require_cpu_features}")
   if(can_run)