diff --git a/llvm/utils/extract_symbols.py b/llvm/utils/extract_symbols.py
index 0cbfd2e2910e1..3829f5b64bb4d 100755
--- a/llvm/utils/extract_symbols.py
+++ b/llvm/utils/extract_symbols.py
@@ -113,6 +113,9 @@ def should_keep_microsoft_symbol(symbol, calling_convention_decoration):
         and (symbol.startswith("?Head@") or symbol.startswith("?Tail@"))
     ):
         return symbol
+    # Skip symbols added by the compiler with -fprofile-generate.
+    elif symbol.startswith("__prof"):
+        return None
     # Keep mangled llvm:: and clang:: function symbols. How we detect these is a
     # bit of a mess and imprecise, but that avoids having to completely demangle
     # the symbol name. The outermost namespace is at the end of the identifier
@@ -131,7 +134,7 @@ def should_keep_microsoft_symbol(symbol, calling_convention_decoration):
     #                 ::= .+@ (list of types)
     #                 ::= .*Z (list of types, varargs)
     # <throw-spec> ::= exceptions are not allowed
-    elif re.search(r"(llvm|clang)@@[A-Z][A-Z0-9_]*[A-JQ].+(X|.+@|.*Z)$", symbol):
+    elif re.search(r"(llvm|clang)@@[A-DG-LO-UW-Z][A-Z0-9_]*[A-JQ].+(X|.+@|.*Z)$", symbol):
         return symbol
     return None