6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-06-13 22:24:07 +00:00
Code Issues Projects Releases Wiki Activity

Make PPC call lowering more aggressive, making the isel matching code simple

Browse Source 
enough to be autogenerated.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28354 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner
2006-05-17 19:00:46 +00:00
parent 7e399c14ab
commit c703a8fbf8
4 changed files with 98 additions and 84 deletions
Download Patch File Download Diff File Expand all files Collapse all files

83
lib/Target/PowerPC/PPCISelLowering.cpp
View File

@ -276,6 +276,8 @@ const char *PPCTargetLowering::getTargetNodeName(unsigned Opcode) const {
case PPCISD::EXTSW_32: return "PPCISD::EXTSW_32";
case PPCISD::STD_32: return "PPCISD::STD_32";
case PPCISD::CALL: return "PPCISD::CALL";
case PPCISD::MTCTR: return "PPCISD::MTCTR";
case PPCISD::BCTRL: return "PPCISD::BCTRL";
case PPCISD::RET_FLAG: return "PPCISD::RET_FLAG";
case PPCISD::MFCR: return "PPCISD::MFCR";
case PPCISD::VCMP: return "PPCISD::VCMP";
@ -877,6 +879,21 @@ static SDOperand LowerFORMAL_ARGUMENTS(SDOperand Op, SelectionDAG &DAG,
return DAG.getNode(ISD::MERGE_VALUES, RetVT, ArgValues);
}
/// isCallCompatibleAddress - Return the immediate to use if the specified
/// 32-bit value is representable in the immediate field of a BxA instruction.
static SDNode *isBLACompatibleAddress(SDOperand Op, SelectionDAG &DAG) {
ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op);
if (!C) return 0;
int Addr = C->getValue();
if ((Addr & 3) != 0 || // Low 2 bits are implicitly zero.
(Addr << 6 >> 6) != Addr)
return 0; // Top 6 bits have to be sext of immediate.
return DAG.getConstant((int)C->getValue() >> 2, MVT::i32).Val;
}
static SDOperand LowerCALL(SDOperand Op, SelectionDAG &DAG) {
SDOperand Chain = Op.getOperand(0);
unsigned CallingConv= cast<ConstantSDNode>(Op.getOperand(1))->getValue();
@ -1026,22 +1043,59 @@ static SDOperand LowerCALL(SDOperand Op, SelectionDAG &DAG) {
InFlag = Chain.getValue(1);
}
// If the callee is a GlobalAddress node (quite common, every direct call is)
// turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
std::vector<MVT::ValueType> NodeTys;
// If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
// direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
// node so that legalize doesn't hack it.
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), Callee.getValueType());
else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee))
Callee = DAG.getTargetExternalSymbol(S->getSymbol(), Callee.getValueType());
else if (SDNode *Dest = isBLACompatibleAddress(Callee, DAG))
// If this is an absolute destination address, use the munged value.
Callee = SDOperand(Dest, 0);
else {
// Otherwise, this is an indirect call. We have to use a MTCTR/BCTRL pair
// to do the call, we can't use PPCISD::CALL.
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
NodeTys.push_back(MVT::Other);
NodeTys.push_back(MVT::Flag);
if (InFlag.Val)
Ops.push_back(InFlag);
Chain = DAG.getNode(PPCISD::MTCTR, NodeTys, Ops);
InFlag = Chain.getValue(1);
// Copy the callee address into R12 on darwin.
Chain = DAG.getCopyToReg(Chain, PPC::R12, Callee, InFlag);
InFlag = Chain.getValue(1);
NodeTys.clear();
NodeTys.push_back(MVT::Other);
NodeTys.push_back(MVT::Flag);
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(InFlag);
Chain = DAG.getNode(PPCISD::BCTRL, NodeTys, Ops);
InFlag = Chain.getValue(1);
Callee.Val = 0;
}
// Create the PPCISD::CALL node itself.
std::vector<MVT::ValueType> NodeTys;
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
if (InFlag.Val)
Ops.push_back(InFlag);
Chain = DAG.getNode(PPCISD::CALL, NodeTys, Ops);
InFlag = Chain.getValue(1);
if (Callee.Val) {
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
if (InFlag.Val)
Ops.push_back(InFlag);
Chain = DAG.getNode(PPCISD::CALL, NodeTys, Ops);
InFlag = Chain.getValue(1);
}
std::vector<SDOperand> ResultVals;
NodeTys.clear();
@ -1086,6 +1140,11 @@ static SDOperand LowerCALL(SDOperand Op, SelectionDAG &DAG) {
DAG.getConstant(NumBytes, MVT::i32));
NodeTys.push_back(MVT::Other);
// If the function returns void, just return the chain.
if (ResultVals.empty())
return Chain;
// Otherwise, merge everything together with a MERGE_VALUES node.
ResultVals.push_back(Chain);
SDOperand Res = DAG.getNode(ISD::MERGE_VALUES, NodeTys, ResultVals);
return Res.getValue(Op.ResNo);