Implement LowerCall_64 for the SPARC v9 64-bit ABI.

There is still no support for byval arguments (which I don't think are
needed) and varargs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178993 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen
2013-04-07 19:10:57 +00:00
parent 0f08eb1359
commit 18fdb398ea
3 changed files with 375 additions and 3 deletions

View File

@ -594,6 +594,15 @@ LowerFormalArguments_64(SDValue Chain,
SDValue
SparcTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const {
if (Subtarget->is64Bit())
return LowerCall_64(CLI, InVals);
return LowerCall_32(CLI, InVals);
}
// Lower a call for the 32-bit ABI.
SDValue
SparcTargetLowering::LowerCall_32(TargetLowering::CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const {
SelectionDAG &DAG = CLI.DAG;
DebugLoc &dl = CLI.DL;
SmallVector<ISD::OutputArg, 32> &Outs = CLI.Outs;
@ -887,6 +896,221 @@ SparcTargetLowering::getSRetArgSize(SelectionDAG &DAG, SDValue Callee) const
return getDataLayout()->getTypeAllocSize(ElementTy);
}
// Lower a call for the 64-bit ABI.
SDValue
SparcTargetLowering::LowerCall_64(TargetLowering::CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const {
SelectionDAG &DAG = CLI.DAG;
DebugLoc DL = CLI.DL;
SDValue Chain = CLI.Chain;
// Analyze operands of the call, assigning locations to each operand.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CLI.CallConv, CLI.IsVarArg, DAG.getMachineFunction(),
DAG.getTarget(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeCallOperands(CLI.Outs, CC_Sparc64);
// Get the size of the outgoing arguments stack space requirement.
// The stack offset computed by CC_Sparc64 includes all arguments.
// We always allocate space for 6 arguments in the prolog.
unsigned ArgsSize = std::max(6*8u, CCInfo.getNextStackOffset()) - 6*8u;
// Keep stack frames 16-byte aligned.
ArgsSize = RoundUpToAlignment(ArgsSize, 16);
// Adjust the stack pointer to make room for the arguments.
// FIXME: Use hasReservedCallFrame to avoid %sp adjustments around all calls
// with more than 6 arguments.
Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(ArgsSize, true));
// Collect the set of registers to pass to the function and their values.
// This will be emitted as a sequence of CopyToReg nodes glued to the call
// instruction.
SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
// Collect chains from all the memory opeations that copy arguments to the
// stack. They must follow the stack pointer adjustment above and precede the
// call instruction itself.
SmallVector<SDValue, 8> MemOpChains;
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
const CCValAssign &VA = ArgLocs[i];
SDValue Arg = CLI.OutVals[i];
// Promote the value if needed.
switch (VA.getLocInfo()) {
default:
llvm_unreachable("Unknown location info!");
case CCValAssign::Full:
break;
case CCValAssign::SExt:
Arg = DAG.getNode(ISD::SIGN_EXTEND, DL, VA.getLocVT(), Arg);
break;
case CCValAssign::ZExt:
Arg = DAG.getNode(ISD::ZERO_EXTEND, DL, VA.getLocVT(), Arg);
break;
case CCValAssign::AExt:
Arg = DAG.getNode(ISD::ANY_EXTEND, DL, VA.getLocVT(), Arg);
break;
case CCValAssign::BCvt:
Arg = DAG.getNode(ISD::BITCAST, DL, VA.getLocVT(), Arg);
break;
}
if (VA.isRegLoc()) {
// The custom bit on an i32 return value indicates that it should be
// passed in the high bits of the register.
if (VA.getValVT() == MVT::i32 && VA.needsCustom()) {
Arg = DAG.getNode(ISD::SHL, DL, MVT::i64, Arg,
DAG.getConstant(32, MVT::i32));
// The next value may go in the low bits of the same register.
// Handle both at once.
if (i+1 < ArgLocs.size() && ArgLocs[i+1].isRegLoc() &&
ArgLocs[i+1].getLocReg() == VA.getLocReg()) {
SDValue NV = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i64,
CLI.OutVals[i+1]);
Arg = DAG.getNode(ISD::OR, DL, MVT::i64, Arg, NV);
// Skip the next value, it's already done.
++i;
}
}
// The argument registers are described in term of the callee's register
// window, so translate I0-I7 -> O0-O7.
unsigned Reg = VA.getLocReg();
if (Reg >= SP::I0 && Reg <= SP::I7)
Reg = Reg - SP::I0 + SP::O0;
RegsToPass.push_back(std::make_pair(Reg, Arg));
continue;
}
assert(VA.isMemLoc());
// Create a store off the stack pointer for this argument.
SDValue StackPtr = DAG.getRegister(SP::O6, getPointerTy());
// The argument area starts at %fp+BIAS+128 in the callee frame,
// %sp+BIAS+128 in ours.
SDValue PtrOff = DAG.getIntPtrConstant(VA.getLocMemOffset() +
Subtarget->getStackPointerBias() +
128);
PtrOff = DAG.getNode(ISD::ADD, DL, getPointerTy(), StackPtr, PtrOff);
MemOpChains.push_back(DAG.getStore(Chain, DL, Arg, PtrOff,
MachinePointerInfo(),
false, false, 0));
}
// Emit all stores, make sure they occur before the call.
if (!MemOpChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
&MemOpChains[0], MemOpChains.size());
// Build a sequence of CopyToReg nodes glued together with token chain and
// glue operands which copy the outgoing args into registers. The InGlue is
// necessary since all emitted instructions must be stuck together in order
// to pass the live physical registers.
SDValue InGlue;
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
Chain = DAG.getCopyToReg(Chain, DL,
RegsToPass[i].first, RegsToPass[i].second, InGlue);
InGlue = 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.
// Likewise ExternalSymbol -> TargetExternalSymbol.
SDValue Callee = CLI.Callee;
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL, getPointerTy());
else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
Callee = DAG.getTargetExternalSymbol(E->getSymbol(), getPointerTy());
// Build the operands for the call instruction itself.
SmallVector<SDValue, 8> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
Ops.push_back(DAG.getRegister(RegsToPass[i].first,
RegsToPass[i].second.getValueType()));
// Make sure the CopyToReg nodes are glued to the call instruction which
// consumes the registers.
if (InGlue.getNode())
Ops.push_back(InGlue);
// Now the call itself.
SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
Chain = DAG.getNode(SPISD::CALL, DL, NodeTys, &Ops[0], Ops.size());
InGlue = Chain.getValue(1);
// Revert the stack pointer immediately after the call.
Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(ArgsSize, true),
DAG.getIntPtrConstant(0, true), InGlue);
InGlue = Chain.getValue(1);
// Now extract the return values. This is more or less the same as
// LowerFormalArguments_64.
// Assign locations to each value returned by this call.
SmallVector<CCValAssign, 16> RVLocs;
CCState RVInfo(CLI.CallConv, CLI.IsVarArg, DAG.getMachineFunction(),
DAG.getTarget(), RVLocs, *DAG.getContext());
RVInfo.AnalyzeCallResult(CLI.Ins, CC_Sparc64);
// Copy all of the result registers out of their specified physreg.
for (unsigned i = 0; i != RVLocs.size(); ++i) {
CCValAssign &VA = RVLocs[i];
unsigned Reg = VA.getLocReg();
// Remap I0-I7 -> O0-O7.
if (Reg >= SP::I0 && Reg <= SP::I7)
Reg = Reg - SP::I0 + SP::O0;
// When returning 'inreg {i32, i32 }', two consecutive i32 arguments can
// reside in the same register in the high and low bits. Reuse the
// CopyFromReg previous node to avoid duplicate copies.
SDValue RV;
if (RegisterSDNode *SrcReg = dyn_cast<RegisterSDNode>(Chain.getOperand(1)))
if (SrcReg->getReg() == Reg && Chain->getOpcode() == ISD::CopyFromReg)
RV = Chain.getValue(0);
// But usually we'll create a new CopyFromReg for a different register.
if (!RV.getNode()) {
RV = DAG.getCopyFromReg(Chain, DL, Reg, RVLocs[i].getLocVT(), InGlue);
Chain = RV.getValue(1);
InGlue = Chain.getValue(2);
}
// Get the high bits for i32 struct elements.
if (VA.getValVT() == MVT::i32 && VA.needsCustom())
RV = DAG.getNode(ISD::SRL, DL, VA.getLocVT(), RV,
DAG.getConstant(32, MVT::i32));
// The callee promoted the return value, so insert an Assert?ext SDNode so
// we won't promote the value again in this function.
switch (VA.getLocInfo()) {
case CCValAssign::SExt:
RV = DAG.getNode(ISD::AssertSext, DL, VA.getLocVT(), RV,
DAG.getValueType(VA.getValVT()));
break;
case CCValAssign::ZExt:
RV = DAG.getNode(ISD::AssertZext, DL, VA.getLocVT(), RV,
DAG.getValueType(VA.getValVT()));
break;
default:
break;
}
// Truncate the register down to the return value type.
if (VA.isExtInLoc())
RV = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), RV);
InVals.push_back(RV);
}
return Chain;
}
//===----------------------------------------------------------------------===//
// TargetLowering Implementation
//===----------------------------------------------------------------------===//