[turbofan] Add Float32(Max|Min) machine operators.

test/cctest/compiler/value-helper.h

Index: test/cctest/compiler/value-helper.h
diff --git a/test/cctest/compiler/value-helper.h b/test/cctest/compiler/value-helper.h
index cdc7e658cb068fcf903f102dd65250176f361146..297bccb05bac604b77f240178f96145ba60c3478 100644
--- a/test/cctest/compiler/value-helper.h
+++ b/test/cctest/compiler/value-helper.h
@@ -332,6 +332,7 @@ static inline void CheckFloatEq(volatile float x, volatile float y) {
     CHECK(std::isnan(y));
   } else {
     CHECK_EQ(x, y);
+    CHECK_EQ(std::signbit(x), std::signbit(y));
   }
 }
 
@@ -346,6 +347,7 @@ static inline void CheckDoubleEq(volatile double x, volatile double y) {
     CHECK(std::isnan(y));
   } else {
     CHECK_EQ(x, y);
+    CHECK_EQ(std::signbit(x), std::signbit(y));
   }
 }