MIPS: Faster implementation of Math.exp()

src/mips/lithium-mips.cc

Index: src/mips/lithium-mips.cc
diff --git a/src/mips/lithium-mips.cc b/src/mips/lithium-mips.cc
index 2d2a413e897869a7ef97851785c6a817aed9a003..1c548fcdfac104588a4d39dd31516fa6a5f6dc99 100644
--- a/src/mips/lithium-mips.cc
+++ b/src/mips/lithium-mips.cc
@@ -297,6 +297,11 @@ void LUnaryMathOperation::PrintDataTo(StringStream* stream) {
 }
 
 
+void LMathExp::PrintDataTo(StringStream* stream) {
+  value()->PrintTo(stream);
+}
+
+
 void LLoadContextSlot::PrintDataTo(StringStream* stream) {
   context()->PrintTo(stream);
   stream->Add("[%d]", slot_index());
@@ -1040,6 +1045,15 @@ LInstruction* LChunkBuilder::DoUnaryMathOperation(HUnaryMathOperation* instr) {
     LOperand* input = UseFixedDouble(instr->value(), f4);
     LUnaryMathOperation* result = new(zone()) LUnaryMathOperation(input, NULL);
     return MarkAsCall(DefineFixedDouble(result, f4), instr);
+  } else if (op == kMathExp) {
+    ASSERT(instr->representation().IsDouble());
+    ASSERT(instr->value()->representation().IsDouble());
+    LOperand* input = UseTempRegister(instr->value());
+    LOperand* temp1 = TempRegister();
+    LOperand* temp2 = TempRegister();
+    LOperand* double_temp = FixedTemp(f6);  // Chosen by fair dice roll.
+    LMathExp* result = new(zone()) LMathExp(input, double_temp, temp1, temp2);
+    return DefineAsRegister(result);
   } else if (op == kMathPowHalf) {
     // Input cannot be the same as the result.
     // See lithium-codegen-mips.cc::DoMathPowHalf.