Bug 1763163 - Part 3: Reduce temp registers for LNotV. r=iain

We can use the output register as a temp register for `testValueTruthy()`.

Depends on D142955

Differential Revision: https://phabricator.services.mozilla.com/D142956

js/src/jit/CodeGenerator.cpp

@@ -10887,12 +10887,11 @@ void CodeGenerator::visitNotV(LNotV* lir) {
 
   ValueOperand input = ToValue(lir, LNotV::InputIndex);
   Register temp1 = ToRegister(lir->temp1());
-  Register temp2 = ToRegister(lir->temp2());
   FloatRegister floatTemp = ToFloatRegister(lir->temp0());
   Register output = ToRegister(lir->output());
   const TypeDataList& observedTypes = lir->mir()->observedTypes();
 
-  testValueTruthy(input, temp1, temp2, floatTemp, observedTypes, ifTruthy,
+  testValueTruthy(input, temp1, output, floatTemp, observedTypes, ifTruthy,
                   ifFalsy, ool);
 
   Label join;

js/src/jit/LIROps.yaml

@@ -770,7 +770,7 @@
   result_type: WordSized
   operands:
     input: BoxedValue
-  num_temps: 3
+  num_temps: 2
   mir_op: Not
 
 - name: BitNotI

js/src/jit/Lowering.cpp

@@ -3495,7 +3495,7 @@ void LIRGenerator::visitNot(MNot* ins) {
       define(new (alloc()) LNotO(useRegister(op)), ins);
       break;
     case MIRType::Value: {
-      auto* lir = new (alloc()) LNotV(useBox(op), tempDouble(), temp(), temp());
+      auto* lir = new (alloc()) LNotV(useBox(op), tempDouble(), temp());
       define(lir, ins);
       break;
     }