MIPS: Faster implementation of Math.exp()

src/mips/lithium-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 279 matching lines @@
   stream->Add("#%d / ", arity());
 }
 
 
 void LUnaryMathOperation::PrintDataTo(StringStream* stream) {
   stream->Add("/%s ", hydrogen()->OpName());
   value()->PrintTo(stream);
 }
 
 
+void LMathExp::PrintDataTo(StringStream* stream) {
+  value()->PrintTo(stream);
+}
+
+
 void LLoadContextSlot::PrintDataTo(StringStream* stream) {
   context()->PrintTo(stream);
   stream->Add("[%d]", slot_index());
 }
 
 
 void LStoreContextSlot::PrintDataTo(StringStream* stream) {
   context()->PrintTo(stream);
   stream->Add("[%d] <- ", slot_index());
   value()->PrintTo(stream);
@@ skipping 723 matching lines @@
   return MarkAsCall(DefineFixed(result, v0), instr, CANNOT_DEOPTIMIZE_EAGERLY);
 }
 
 
 LInstruction* LChunkBuilder::DoUnaryMathOperation(HUnaryMathOperation* instr) {
   BuiltinFunctionId op = instr->op();
   if (op == kMathLog || op == kMathSin || op == kMathCos || op == kMathTan) {
     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.
     LOperand* input = UseFixedDouble(instr->value(), f8);
     LOperand* temp = FixedTemp(f6);
     LUnaryMathOperation* result = new(zone()) LUnaryMathOperation(input, temp);
     return DefineFixedDouble(result, f4);
   } else {
     LOperand* input = UseRegisterAtStart(instr->value());
     LOperand* temp = (op == kMathFloor) ? TempRegister() : NULL;
@@ skipping 1174 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseRegister(instr->index());
   return DefineAsRegister(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal