[parser] Fix intrinsic name matching

Bug: chromium:1028669
Change-Id: I3f690508f09a98b6b6b0f3808033fac4fae40700
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1940248
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65207}

src/objects/contexts.cc

@@ -442,7 +442,11 @@ int Context::IntrinsicIndexForName(Handle<String> string) {
 #undef COMPARE_NAME
 
 #define COMPARE_NAME(index, type, name)                                      \
-  if (strncmp(string, #name, length) == 0) return index;
+  {                                                                          \
+    const int name_length = static_cast<int>(arraysize(#name)) - 1;          \
+    if ((length == name_length) && strncmp(string, #name, name_length) == 0) \
+      return index;                                                          \
+  }
 
 int Context::IntrinsicIndexForName(const unsigned char* unsigned_string,
                                    int length) {