Insert ANY_EXTEND node instead of invalid truncate during DAG Combining (X & 1),

when needed. This fixes PR7001

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102838 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Anton Korobeynikov 2010-05-01 12:52:34 +00:00
parent 1b17614a72
commit 17458a786e
2 changed files with 33 additions and 1 deletions

View File

@ -1882,10 +1882,15 @@ TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1,
isa<ConstantSDNode>(Op0.getOperand(1)) &&
cast<ConstantSDNode>(Op0.getOperand(1))->getAPIntValue() == 1) {
// If this is (X&1) == / != 1, normalize it to (X&1) != / == 0.
if (Op0.getValueType() != VT)
if (Op0.getValueType().bitsGT(VT))
Op0 = DAG.getNode(ISD::AND, dl, VT,
DAG.getNode(ISD::TRUNCATE, dl, VT, Op0.getOperand(0)),
DAG.getConstant(1, VT));
else if (Op0.getValueType().bitsLT(VT))
Op0 = DAG.getNode(ISD::AND, dl, VT,
DAG.getNode(ISD::ANY_EXTEND, dl, VT, Op0.getOperand(0)),
DAG.getConstant(1, VT));
return DAG.getSetCC(dl, VT, Op0,
DAG.getConstant(0, Op0.getValueType()),
Cond == ISD::SETEQ ? ISD::SETNE : ISD::SETEQ);

View File

@ -0,0 +1,27 @@
; RUN: llc < %s
; PR7001
target datalayout = "e-p:16:16:16-i8:8:8-i16:16:16-i32:16:32-n8:16"
target triple = "msp430-elf"
define i16 @main() nounwind {
entry:
br label %while.cond
while.cond: ; preds = %while.body, %entry
br i1 undef, label %land.rhs, label %land.end
land.rhs: ; preds = %while.cond
br label %land.end
land.end: ; preds = %land.rhs, %while.cond
%0 = phi i1 [ false, %while.cond ], [ undef, %land.rhs ] ; <i1> [#uses=1]
br i1 %0, label %while.body, label %while.end
while.body: ; preds = %land.end
%tmp4 = load i16* undef ; <i16> [#uses=0]
br label %while.cond
while.end: ; preds = %land.end
ret i16 undef
}