[Turbofan] Simplify operand canonicalization on archs with simple FP aliasing.

src/compiler/instruction.h

Index: src/compiler/instruction.h
diff --git a/src/compiler/instruction.h b/src/compiler/instruction.h
index af7e592e5f93c4a0596c3c6d7b280c3160faca15..7130c3d53f3b9ea07a97aa9bf811506465037622 100644
--- a/src/compiler/instruction.h
+++ b/src/compiler/instruction.h
@@ -606,10 +606,17 @@ bool InstructionOperand::IsSimd128StackSlot() const {
 uint64_t InstructionOperand::GetCanonicalizedValue() const {
   if (IsAllocated() || IsExplicit()) {
     MachineRepresentation rep = LocationOperand::cast(this)->representation();
-    // Preserve FP representation so we can check for interference on
-    // architectures with complex register aliasing.
-    MachineRepresentation canonical =
-        IsFPRegister() ? rep : MachineRepresentation::kNone;
+    MachineRepresentation canonical = MachineRepresentation::kNone;
+    if (IsFloatingPoint(rep)) {
+      if (kSimpleFPAliasing) {
+        // Archs with simple aliasing can treat all FP operands the same.
+        canonical = MachineRepresentation::kFloat64;
+      } else {
+        // We need to distinguish FP operands of different reps when FP
+        // aliasing is not simple (e.g. ARM).
+        canonical = rep;
+      }
+    }
     return InstructionOperand::KindField::update(
         LocationOperand::RepresentationField::update(this->value_, canonical),
         LocationOperand::EXPLICIT);
@@ -617,7 +624,6 @@ uint64_t InstructionOperand::GetCanonicalizedValue() const {
   return this->value_;
 }
 
-
 // Required for maps that don't care about machine type.
 struct CompareOperandModuloType {
   bool operator()(const InstructionOperand& a,