[turbofan] Make Float32Neg and Float64Neg mandatory operators.

src/compiler/mips64/instruction-selector-mips64.cc

Index: src/compiler/mips64/instruction-selector-mips64.cc
diff --git a/src/compiler/mips64/instruction-selector-mips64.cc b/src/compiler/mips64/instruction-selector-mips64.cc
index b2771fc4f644531576e375d70c4d03db5c83bce6..471e50d1dd37faf5eed40a655f248f032c41ce36 100644
--- a/src/compiler/mips64/instruction-selector-mips64.cc
+++ b/src/compiler/mips64/instruction-selector-mips64.cc
@@ -1300,9 +1300,13 @@ void InstructionSelector::VisitFloat64RoundTiesEven(Node* node) {
   VisitRR(this, kMips64Float64RoundTiesEven, node);
 }
 
-void InstructionSelector::VisitFloat32Neg(Node* node) { UNREACHABLE(); }
+void InstructionSelector::VisitFloat32Neg(Node* node) {
+  VisitRR(this, kMips64NegS, node);
+}
 
-void InstructionSelector::VisitFloat64Neg(Node* node) { UNREACHABLE(); }
+void InstructionSelector::VisitFloat64Neg(Node* node) {
+  VisitRR(this, kMips64NegD, node);
+}
 
 void InstructionSelector::VisitFloat64Ieee754Binop(Node* node,
                                                    InstructionCode opcode) {