[turbofan] Implemented the optional Float32RoundTruncate operator.

src/compiler/machine-operator.h

Index: src/compiler/machine-operator.h
diff --git a/src/compiler/machine-operator.h b/src/compiler/machine-operator.h
index 03c036bb87f4d0b1c7c0725f1b1a4d8e67f6b7be..cd0297b53dc88557c83830980ba9533f7d81eac1 100644
--- a/src/compiler/machine-operator.h
+++ b/src/compiler/machine-operator.h
@@ -120,21 +120,23 @@ class MachineOperatorBuilder final : public ZoneObject {
     kFloat64RoundDown = 1u << 5,
     kFloat32RoundUp = 1u << 6,
     kFloat64RoundUp = 1u << 7,
-    kFloat64RoundTruncate = 1u << 8,
-    kFloat64RoundTiesEven = 1u << 9,
-    kFloat64RoundTiesAway = 1u << 10,
-    kInt32DivIsSafe = 1u << 11,
-    kUint32DivIsSafe = 1u << 12,
-    kWord32ShiftIsSafe = 1u << 13,
-    kWord32Ctz = 1u << 14,
-    kWord64Ctz = 1u << 15,
-    kWord32Popcnt = 1u << 16,
-    kWord64Popcnt = 1u << 17,
+    kFloat32RoundTruncate = 1u << 8,
+    kFloat64RoundTruncate = 1u << 9,
+    kFloat64RoundTiesEven = 1u << 10,
+    kFloat64RoundTiesAway = 1u << 11,
+    kInt32DivIsSafe = 1u << 12,
+    kUint32DivIsSafe = 1u << 13,
+    kWord32ShiftIsSafe = 1u << 14,
+    kWord32Ctz = 1u << 15,
+    kWord64Ctz = 1u << 16,
+    kWord32Popcnt = 1u << 17,
+    kWord64Popcnt = 1u << 18,
     kAllOptionalOps = kFloat32Max | kFloat32Min | kFloat64Max | kFloat64Min |
                       kFloat32RoundDown | kFloat64RoundDown | kFloat32RoundUp |
-                      kFloat64RoundUp | kFloat64RoundTruncate |
-                      kFloat64RoundTiesAway | kFloat64RoundTiesEven |
-                      kWord32Ctz | kWord64Ctz | kWord32Popcnt | kWord64Popcnt
+                      kFloat64RoundUp | kFloat32RoundTruncate |
+                      kFloat64RoundTruncate | kFloat64RoundTiesAway |
+                      kFloat64RoundTiesEven | kWord32Ctz | kWord64Ctz |
+                      kWord32Popcnt | kWord64Popcnt
   };
   typedef base::Flags<Flag, unsigned> Flags;
 
@@ -274,6 +276,7 @@ class MachineOperatorBuilder final : public ZoneObject {
   const OptionalOperator Float64RoundDown();
   const OptionalOperator Float32RoundUp();
   const OptionalOperator Float64RoundUp();
+  const OptionalOperator Float32RoundTruncate();
   const OptionalOperator Float64RoundTruncate();
   const OptionalOperator Float64RoundTiesAway();
   const OptionalOperator Float64RoundTiesEven();