Implemented the ctz Turbo Fan operator for x64.

src/compiler/mips64/instruction-selector-mips64.cc

Index: src/compiler/mips64/instruction-selector-mips64.cc
diff --git a/src/compiler/mips64/instruction-selector-mips64.cc b/src/compiler/mips64/instruction-selector-mips64.cc
index 3ab119e6e2afb6bc35aacd0bb4d60f63c785c843..b0841790621b02f81e2588ea6aecbad831ffcbc4 100644
--- a/src/compiler/mips64/instruction-selector-mips64.cc
+++ b/src/compiler/mips64/instruction-selector-mips64.cc
@@ -324,6 +324,9 @@ void InstructionSelector::VisitWord32Clz(Node* node) {
 void InstructionSelector::VisitWord32Ctz(Node* node) { UNREACHABLE(); }
 
 
+void InstructionSelector::VisitWord64Ctz(Node* node) { UNREACHABLE(); }
+
+
 void InstructionSelector::VisitWord32Popcnt(Node* node) { UNREACHABLE(); }