[builtins] Introduce proper base::ieee754::log.

src/crankshaft/x64/lithium-x64.cc

Index: src/crankshaft/x64/lithium-x64.cc
diff --git a/src/crankshaft/x64/lithium-x64.cc b/src/crankshaft/x64/lithium-x64.cc
index 7a29d9930478d44fec747c7600f6e65d4220de98..22d8ac5b7733a2026fcca17acdacc8ffefb15e19 100644
--- a/src/crankshaft/x64/lithium-x64.cc
+++ b/src/crankshaft/x64/lithium-x64.cc
@@ -1155,8 +1155,9 @@ LInstruction* LChunkBuilder::DoMathAbs(HUnaryMathOperation* instr) {
 LInstruction* LChunkBuilder::DoMathLog(HUnaryMathOperation* instr) {
   DCHECK(instr->representation().IsDouble());
   DCHECK(instr->value()->representation().IsDouble());
-  LOperand* input = UseRegisterAtStart(instr->value());
-  return MarkAsCall(DefineSameAsFirst(new(zone()) LMathLog(input)), instr);
+  LOperand* input = UseFixedDouble(instr->value(), xmm0);
+  return MarkAsCall(DefineFixedDouble(new (zone()) LMathLog(input), xmm0),
+                    instr);
 }