[turbofan] Remove Float32 truncation.

R=jarin@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2407153007
Cr-Commit-Position: refs/heads/master@{#40266}

src/compiler/representation-change.cc

@@ -24,8 +24,6 @@ const char* Truncation::description() const {
       return "truncate-to-word32";
     case TruncationKind::kWord64:
       return "truncate-to-word64";
-    case TruncationKind::kFloat32:
-      return "truncate-to-float32";
     case TruncationKind::kFloat64:
       return "truncate-to-float64";
     case TruncationKind::kAny:
@@ -42,15 +40,15 @@ const char* Truncation::description() const {
 //     ^            ^
 //     \            |
 //      \         kFloat64  <--+
-//       \        ^    ^       |
-//        \       /    |       |
-//         kWord32  kFloat32  kBool
-//               ^     ^      ^
-//               \     |      /
-//                \    |     /
-//                 \   |    /
-//                  \  |   /
-//                   \ |  /
+//       \        ^            |
+//        \       /            |
+//         kWord32           kBool
+//               ^            ^
+//               \            /
+//                \          /
+//                 \        /
+//                  \      /
+//                   \    /
 //                   kNone
 
 // static
@@ -87,9 +85,6 @@ bool Truncation::LessGeneral(TruncationKind rep1, TruncationKind rep2) {
              rep2 == TruncationKind::kFloat64 || rep2 == TruncationKind::kAny;
     case TruncationKind::kWord64:
       return rep2 == TruncationKind::kWord64;
-    case TruncationKind::kFloat32:
-      return rep2 == TruncationKind::kFloat32 ||
-             rep2 == TruncationKind::kFloat64 || rep2 == TruncationKind::kAny;
     case TruncationKind::kFloat64:
       return rep2 == TruncationKind::kFloat64 || rep2 == TruncationKind::kAny;
     case TruncationKind::kAny:

src/compiler/representation-change.h

@@ -19,7 +19,6 @@ class Truncation final {
   static Truncation Bool() { return Truncation(TruncationKind::kBool); }
   static Truncation Word32() { return Truncation(TruncationKind::kWord32); }
   static Truncation Word64() { return Truncation(TruncationKind::kWord64); }
-  static Truncation Float32() { return Truncation(TruncationKind::kFloat32); }
   static Truncation Float64() { return Truncation(TruncationKind::kFloat64); }
   static Truncation Any() { return Truncation(TruncationKind::kAny); }
 
@@ -63,7 +62,6 @@ class Truncation final {
     kBool,
     kWord32,
     kWord64,
-    kFloat32,
     kFloat64,
     kAny
   };
@@ -134,8 +132,8 @@ class UseInfo {
   static UseInfo Bool() {
     return UseInfo(MachineRepresentation::kBit, Truncation::Bool());
   }
-  static UseInfo TruncatingFloat32() {
-    return UseInfo(MachineRepresentation::kFloat32, Truncation::Float32());
+  static UseInfo Float32() {
+    return UseInfo(MachineRepresentation::kFloat32, Truncation::Any());
   }
   static UseInfo TruncatingFloat64() {
     return UseInfo(MachineRepresentation::kFloat64, Truncation::Float64());

src/compiler/simplified-lowering.cc

@@ -129,7 +129,7 @@ UseInfo TruncatingUseInfoFromRepresentation(MachineRepresentation rep) {
     case MachineRepresentation::kFloat64:
       return UseInfo::TruncatingFloat64();
     case MachineRepresentation::kFloat32:
-      return UseInfo::TruncatingFloat32();
+      return UseInfo::Float32();
     case MachineRepresentation::kWord64:
       return UseInfo::TruncatingWord64();
     case MachineRepresentation::kWord8: