Arithmetic instructions don't set EFLAGS bits OF and CF bits
the same say the "test" instruction does in overflow cases,
so eliminating the test is only safe when those bits aren't
needed, as is the case for COND_E and COND_NE, or if it
can be proven that no overflow will occur. For now, just
restrict the optimization to COND_E and COND_NE and don't
do any overflow analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66318 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 5d3f287..6666b45 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -661,12 +661,13 @@
unsigned cmovOpc) const;
/// Emit nodes that will be selected as "test Op0,Op0", or something
- /// equivalent.
- SDValue EmitTest(SDValue Op0, SelectionDAG &DAG);
+ /// equivalent, for use with the given x86 condition code.
+ SDValue EmitTest(SDValue Op0, unsigned X86CC, SelectionDAG &DAG);
/// Emit nodes that will be selected as "cmp Op0,Op1", or something
- /// equivalent.
- SDValue EmitCmp(SDValue Op0, SDValue Op1, SelectionDAG &DAG);
+ /// equivalent, for use with the given x86 condition code.
+ SDValue EmitCmp(SDValue Op0, SDValue Op1, unsigned X86CC,
+ SelectionDAG &DAG);
};
namespace X86 {