[builtins] Introduce proper Float64Exp operator.

src/compiler/instruction-selector.cc

Index: src/compiler/instruction-selector.cc
diff --git a/src/compiler/instruction-selector.cc b/src/compiler/instruction-selector.cc
index 7b9b8e1e1a2e1ef3c9a8e5c84038bf0d815c80d2..048875732fa5f0a807f74cc76bfad5fa45367a10 100644
--- a/src/compiler/instruction-selector.cc
+++ b/src/compiler/instruction-selector.cc
@@ -1138,6 +1138,8 @@ void InstructionSelector::VisitNode(Node* node) {
       return MarkAsFloat64(node), VisitFloat64Atan(node);
     case IrOpcode::kFloat64Atan2:
       return MarkAsFloat64(node), VisitFloat64Atan2(node);
+    case IrOpcode::kFloat64Exp:
+      return MarkAsFloat64(node), VisitFloat64Exp(node);
     case IrOpcode::kFloat64Log:
       return MarkAsFloat64(node), VisitFloat64Log(node);
     case IrOpcode::kFloat64Log1p:
@@ -1259,6 +1261,10 @@ void InstructionSelector::VisitFloat64Atan2(Node* node) {
   VisitFloat64Ieee754Binop(node, kIeee754Float64Atan2);
 }
 
+void InstructionSelector::VisitFloat64Exp(Node* node) {
+  VisitFloat64Ieee754Unop(node, kIeee754Float64Exp);
+}
+
 void InstructionSelector::VisitFloat64Log(Node* node) {
   VisitFloat64Ieee754Unop(node, kIeee754Float64Log);
 }