Allow the target to specify 'expand' if they just require the amount to

be subtracted from the stack pointer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25331 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2006-01-15 08:54:32 +00:00
parent bce8887cee
commit 903d278a9b

View File

@ -847,22 +847,32 @@ SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) {
switch (TLI.getOperationAction(Node->getOpcode(),
Node->getValueType(0))) {
default: assert(0 && "This action is not supported yet!");
case TargetLowering::Custom: {
case TargetLowering::Expand: {
unsigned SPReg = TLI.getStackPointerRegisterToSaveRestore();
assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
" not tell us which reg is the stack pointer!");
SDOperand Chain = Tmp1.getOperand(0);
SDOperand Size = Tmp2.getOperand(1);
SDOperand SP = DAG.getCopyFromReg(Chain, SPReg, Node->getValueType(0));
Tmp1 = DAG.getNode(ISD::SUB, Node->getValueType(0), SP, Size); // Value
Tmp2 = DAG.getCopyToReg(SP.getValue(1), SPReg, Tmp1); // Output chain
break;
}
case TargetLowering::Custom:
Tmp3 = TLI.LowerOperation(Tmp1, DAG);
if (Tmp3.Val) {
Tmp1 = LegalizeOp(Tmp3);
Tmp2 = LegalizeOp(Tmp3.getValue(1));
}
// FALLTHROUGH if the target thinks it is legal.
}
break;
case TargetLowering::Legal:
// Since this op produce two values, make sure to remember that we
// legalized both of them.
AddLegalizedOperand(SDOperand(Node, 0), Tmp1);
AddLegalizedOperand(SDOperand(Node, 1), Tmp2);
return Op.ResNo ? Tmp2 : Tmp1;
break;
}
assert(0 && "Unreachable");
// Since this op produce two values, make sure to remember that we
// legalized both of them.
AddLegalizedOperand(SDOperand(Node, 0), Tmp1);
AddLegalizedOperand(SDOperand(Node, 1), Tmp2);
return Op.ResNo ? Tmp2 : Tmp1;
}
case ISD::TAILCALL:
case ISD::CALL: {