[turbofan] Generalize constant propagation.

testing/gmock-support.h

Index: testing/gmock-support.h
diff --git a/testing/gmock-support.h b/testing/gmock-support.h
index ad39e9269bb24404a7a9c52fd39f2479c2567f64..012775b5cbffbf6b33de4fb3bb67c6ae04583ef3 100644
--- a/testing/gmock-support.h
+++ b/testing/gmock-support.h
@@ -5,6 +5,7 @@
 #ifndef V8_TESTING_GMOCK_SUPPORT_H_
 #define V8_TESTING_GMOCK_SUPPORT_H_
 
+#include <cmath>
 #include <cstring>
 
 #include "testing/gmock/include/gmock/gmock.h"
@@ -96,6 +97,12 @@ inline Matcher<T> CaptureEq(Capture<T>* capture) {
   return MakeMatcher(new internal::CaptureEqMatcher<T>(capture));
 }
 
+
+// Creates a polymorphic matcher that matches any floating point NaN value.
+MATCHER(IsNaN, std::string(negation ? "isn't" : "is") + " not a number") {
+  return std::isnan(arg);
+}
+
 }  // namespace testing
 
 #endif  // V8_TESTING_GMOCK_SUPPORT_H_