Fix a bug in getARMCMP (which translate CondCode to ARM specific CC) when the RHS is a constant.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33775 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2007-02-02 01:53:26 +00:00
parent b0636156ef
commit 9a2ef9509e

View File

@ -859,7 +859,7 @@ static bool isFloatingPointZero(SDOperand Op) {
return false;
}
static bool isLegalCmpImmediate(int C, bool isThumb) {
static bool isLegalCmpImmediate(unsigned C, bool isThumb) {
return ( isThumb && (C & ~255U) == 0) ||
(!isThumb && ARM_AM::getSOImmVal(C) != -1);
}
@ -869,38 +869,36 @@ static bool isLegalCmpImmediate(int C, bool isThumb) {
static SDOperand getARMCmp(SDOperand LHS, SDOperand RHS, ISD::CondCode CC,
SDOperand &ARMCC, SelectionDAG &DAG, bool isThumb) {
if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS.Val)) {
int C = (int)RHSC->getValue();
unsigned C = RHSC->getValue();
if (!isLegalCmpImmediate(C, isThumb)) {
// Constant does not fit, try adjusting it by one?
switch (CC) {
default: break;
case ISD::SETLT:
case ISD::SETULT:
case ISD::SETGE:
case ISD::SETUGE:
if (isLegalCmpImmediate(C-1, isThumb)) {
switch (CC) {
default: break;
case ISD::SETLT: CC = ISD::SETLE; break;
case ISD::SETULT: CC = ISD::SETULE; break;
case ISD::SETGE: CC = ISD::SETGT; break;
case ISD::SETUGE: CC = ISD::SETUGT; break;
}
CC = (CC == ISD::SETLT) ? ISD::SETLE : ISD::SETGT;
RHS = DAG.getConstant(C-1, MVT::i32);
}
break;
case ISD::SETULT:
case ISD::SETUGE:
if (C > 0 && isLegalCmpImmediate(C-1, isThumb)) {
CC = (CC == ISD::SETULT) ? ISD::SETULE : ISD::SETUGT;
RHS = DAG.getConstant(C-1, MVT::i32);
}
break;
case ISD::SETLE:
case ISD::SETULE:
case ISD::SETGT:
case ISD::SETUGT:
if (isLegalCmpImmediate(C+1, isThumb)) {
switch (CC) {
default: break;
case ISD::SETLE: CC = ISD::SETLT; break;
case ISD::SETULE: CC = ISD::SETULT; break;
case ISD::SETGT: CC = ISD::SETGE; break;
case ISD::SETUGT: CC = ISD::SETUGE; break;
}
CC = (CC == ISD::SETLE) ? ISD::SETLT : ISD::SETGE;
RHS = DAG.getConstant(C+1, MVT::i32);
}
break;
case ISD::SETULE:
case ISD::SETUGT:
if (C < 0xffffffff && isLegalCmpImmediate(C+1, isThumb)) {
CC = (CC == ISD::SETULE) ? ISD::SETULT : ISD::SETUGE;
RHS = DAG.getConstant(C+1, MVT::i32);
}
break;