Subzero: Use a setcc sequence for better icmp lowering.

src/IceTargetLoweringX8632.h

Index: src/IceTargetLoweringX8632.h
diff --git a/src/IceTargetLoweringX8632.h b/src/IceTargetLoweringX8632.h
index 34f187c61735736b92248e119fd3aeae1a0a38f3..8a3c36ecaa29c5e53a0ad21024fbde8fe464b43a 100644
--- a/src/IceTargetLoweringX8632.h
+++ b/src/IceTargetLoweringX8632.h
@@ -415,6 +415,9 @@ protected:
   void _sbb(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Sbb::create(Func, Dest, Src0));
   }
+  void _setcc(Variable *Dest, CondX86::BrCond Condition) {
+    Context.insert(InstX8632Setcc::create(Func, Dest, Condition));
+  }
   void _shl(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Shl::create(Func, Dest, Src0));
   }