Increase the implementation of __memcpy_chk assembly

Use __memcpy_chk assembly to replace the implementation of c functions, which can reduce the use of instructions

Test: llvm-objdump

Change-Id: I5d75601626dc997626f6173d53af301183a64004
Signed-off-by: caowencheng <caowencheng@eswincomputing.com>
diff --git a/libc/bionic/fortify.cpp b/libc/bionic/fortify.cpp
index 73cf973..7dee5e3 100644
--- a/libc/bionic/fortify.cpp
+++ b/libc/bionic/fortify.cpp
@@ -489,9 +489,9 @@
   return strcpy(dst, src);
 }
 
-#if !defined(__arm__) && !defined(__aarch64__)
+#if !defined(__arm__) && !defined(__aarch64__) && !defined(__riscv)
 // Runtime implementation of __memcpy_chk (used directly by compiler, not in headers).
-// arm32 and arm64 have assembler implementations, and don't need this C fallback.
+// arm32,arm64,riscv have assembler implementations, and don't need this C fallback.
 extern "C" void* __memcpy_chk(void* dst, const void* src, size_t count, size_t dst_len) {
   __check_count("memcpy", "count", count);
   __check_buffer_access("memcpy", "write into", count, dst_len);