Fix a bug which caused us to never be able to use signed comparisons for

equality comparisons of a constant.  This allows us to codegen the 'sintzero'
loop in PR1288 as:

LBB1_1: ;cond_next
        li r4, 0
        addi r2, r2, 1
        stw r4, 0(r3)
        addi r3, r3, 4
        cmpwi cr0, r2, -1
        bne cr0, LBB1_1 ;cond_next

instead of:

LBB1_1: ;cond_next
        addi r2, r2, 1
        li r4, 0
        xoris r5, r2, 65535
        stw r4, 0(r3)
        addi r3, r3, 4
        cmplwi cr0, r5, 65535
        bne cr0, LBB1_1 ;cond_next

This implements CodeGen/PowerPC/compare-simm.ll, and also cuts 74
instructions out of kc++.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35590 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index c8a7738372b7f09c8ba4dcba7d3fbd3da3336c63..7a4b29fefbc52f89896df627048a0c97e8f50680 100644 (file)
--- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -508,7 +508,7 @@ SDOperand PPCDAGToDAGISel::SelectCC(SDOperand LHS, SDOperand RHS,
           return SDOperand(CurDAG->getTargetNode(PPC::CMPLWI, MVT::i32, LHS,
                                                  getI32Imm(Imm & 0xFFFF)), 0);
         // If this is a 16-bit signed immediate, fold it.
-        if (isInt16(Imm))
+        if (isInt16((int)Imm))
           return SDOperand(CurDAG->getTargetNode(PPC::CMPWI, MVT::i32, LHS,
                                                  getI32Imm(Imm & 0xFFFF)), 0);