Add support for varargs functions for msp430.

Patch by Job Noorman!

llvm-svn: 168440
This commit is contained in:
Anton Korobeynikov 2012-11-21 17:28:27 +00:00
parent 3414872fc8
commit 568afebcb2
4 changed files with 86 additions and 2 deletions

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@ -164,6 +164,12 @@ MSP430TargetLowering::MSP430TargetLowering(MSP430TargetMachine &tm) :
setOperationAction(ISD::SDIVREM, MVT::i16, Expand);
setOperationAction(ISD::SREM, MVT::i16, Expand);
// varargs support
setOperationAction(ISD::VASTART, MVT::Other, Custom);
setOperationAction(ISD::VAARG, MVT::Other, Expand);
setOperationAction(ISD::VAEND, MVT::Other, Expand);
setOperationAction(ISD::VACOPY, MVT::Other, Expand);
// Libcalls names.
if (HWMultMode == HWMultIntr) {
setLibcallName(RTLIB::MUL_I8, "__mulqi3hw");
@ -192,6 +198,7 @@ SDValue MSP430TargetLowering::LowerOperation(SDValue Op,
case ISD::SIGN_EXTEND: return LowerSIGN_EXTEND(Op, DAG);
case ISD::RETURNADDR: return LowerRETURNADDR(Op, DAG);
case ISD::FRAMEADDR: return LowerFRAMEADDR(Op, DAG);
case ISD::VASTART: return LowerVASTART(Op, DAG);
default:
llvm_unreachable("unimplemented operand");
}
@ -297,7 +304,6 @@ MSP430TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
/// LowerCCCArguments - transform physical registers into virtual registers and
/// generate load operations for arguments places on the stack.
// FIXME: struct return stuff
// FIXME: varargs
SDValue
MSP430TargetLowering::LowerCCCArguments(SDValue Chain,
CallingConv::ID CallConv,
@ -311,6 +317,7 @@ MSP430TargetLowering::LowerCCCArguments(SDValue Chain,
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineRegisterInfo &RegInfo = MF.getRegInfo();
MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
// Assign locations to all of the incoming arguments.
SmallVector<CCValAssign, 16> ArgLocs;
@ -318,7 +325,11 @@ MSP430TargetLowering::LowerCCCArguments(SDValue Chain,
getTargetMachine(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeFormalArguments(Ins, CC_MSP430);
assert(!isVarArg && "Varargs not supported yet");
// Create frame index for the start of the first vararg value
if (isVarArg) {
unsigned Offset = CCInfo.getNextStackOffset();
FuncInfo->setVarArgsFrameIndex(MFI->CreateFixedObject(1, Offset, true));
}
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
@ -957,6 +968,22 @@ SDValue MSP430TargetLowering::LowerFRAMEADDR(SDValue Op,
return FrameAddr;
}
SDValue MSP430TargetLowering::LowerVASTART(SDValue Op,
SelectionDAG &DAG) const {
MachineFunction &MF = DAG.getMachineFunction();
MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
// Frame index of first vararg argument
SDValue FrameIndex = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
getPointerTy());
const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
// Create a store of the frame index to the location operand
return DAG.getStore(Op.getOperand(0), Op.getDebugLoc(), FrameIndex,
Op.getOperand(1), MachinePointerInfo(SV),
false, false, 0);
}
/// getPostIndexedAddressParts - returns true by value, base pointer and
/// offset pointer and addressing mode by reference if this node can be
/// combined with a load / store to form a post-indexed load / store.

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@ -92,6 +92,7 @@ namespace llvm {
SDValue LowerSIGN_EXTEND(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
SDValue getReturnAddressFrameIndex(SelectionDAG &DAG) const;
TargetLowering::ConstraintType

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@ -30,6 +30,9 @@ class MSP430MachineFunctionInfo : public MachineFunctionInfo {
/// ReturnAddrIndex - FrameIndex for return slot.
int ReturnAddrIndex;
/// VarArgsFrameIndex - FrameIndex for start of varargs area.
int VarArgsFrameIndex;
public:
MSP430MachineFunctionInfo() : CalleeSavedFrameSize(0) {}
@ -41,6 +44,9 @@ public:
int getRAIndex() const { return ReturnAddrIndex; }
void setRAIndex(int Index) { ReturnAddrIndex = Index; }
int getVarArgsFrameIndex() const { return VarArgsFrameIndex;}
void setVarArgsFrameIndex(int Index) { VarArgsFrameIndex = Index; }
};
} // End llvm namespace

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@ -0,0 +1,50 @@
; RUN: llc < %s | FileCheck %s
target datalayout = "e-p:16:16:16-i8:8:8-i16:16:16-i32:16:32-n8:16"
target triple = "msp430---elf"
declare void @llvm.va_start(i8*) nounwind
declare void @llvm.va_end(i8*) nounwind
declare void @llvm.va_copy(i8*, i8*) nounwind
define void @va_start(i16 %a, ...) nounwind {
entry:
; CHECK: va_start:
; CHECK: sub.w #2, r1
%vl = alloca i8*, align 2
%vl1 = bitcast i8** %vl to i8*
; CHECK-NEXT: mov.w r1, [[REG:r[0-9]+]]
; CHECK-NEXT: add.w #6, [[REG]]
; CHECK-NEXT: mov.w [[REG]], 0(r1)
call void @llvm.va_start(i8* %vl1)
call void @llvm.va_end(i8* %vl1)
ret void
}
define i16 @va_arg(i8* %vl) nounwind {
entry:
; CHECK: va_arg:
%vl.addr = alloca i8*, align 2
; CHECK: mov.w r15, 0(r1)
store i8* %vl, i8** %vl.addr, align 2
; CHECK: mov.w r15, [[REG:r[0-9]+]]
; CHECK-NEXT: add.w #2, [[REG]]
; CHECK-NEXT: mov.w [[REG]], 0(r1)
%0 = va_arg i8** %vl.addr, i16
; CHECK-NEXT: mov.w 0(r15), r15
ret i16 %0
}
define void @va_copy(i8* %vl) nounwind {
entry:
; CHECK: va_copy:
%vl.addr = alloca i8*, align 2
%vl2 = alloca i8*, align 2
; CHECK: mov.w r15, 2(r1)
store i8* %vl, i8** %vl.addr, align 2
%0 = bitcast i8** %vl2 to i8*
%1 = bitcast i8** %vl.addr to i8*
; CHECK-NEXT: mov.w r15, 0(r1)
call void @llvm.va_copy(i8* %0, i8* %1)
ret void
}