[libFuzzer] reimplement the way we do -only_ascii to allow more 'const' in function declarations. Add a test for -only_ascii. NFC intended

llvm-svn: 270900

1 files changed, 5 insertions, 3 deletions

diff --git a/llvm/lib/Fuzzer/FuzzerUtil.cpp b/llvm/lib/Fuzzer/FuzzerUtil.cpp
index ec592e03f23..420f05d05c4 100644
--- a/llvm/lib/Fuzzer/FuzzerUtil.cpp
+++ b/llvm/lib/Fuzzer/FuzzerUtil.cpp
@@ -164,9 +164,11 @@ bool ToASCII(uint8_t *Data, size_t Size) {
   return Changed;
 }
 
-bool IsASCII(const Unit &U) {
-  for (auto X : U)
-    if (!(isprint(X) || isspace(X))) return false;
+bool IsASCII(const Unit &U) { return IsASCII(U.data(), U.size()); }
+
+bool IsASCII(const uint8_t *Data, size_t Size) {
+  for (size_t i = 0; i < Size; i++)
+    if (!(isprint(Data[i]) || isspace(Data[i]))) return false;
   return true;
 }