Changed stack allocation On LowerFORMAL_ARGUMENTS.

Added comments about new stack allocation.
Expand SelectCC for i32 results


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41527 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bruno Cardoso Lopes 2007-08-28 05:08:16 +00:00
parent dc0c04c0ed
commit a2b1bb5296

View File

@ -15,12 +15,12 @@
#define DEBUG_TYPE "mips-lower"
#include "MipsISelLowering.h"
#include "MipsMachineFunction.h"
#include "MipsTargetMachine.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Intrinsics.h"
#include "llvm/CallingConv.h"
#include "llvm/ADT/VectorExtras.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
@ -76,8 +76,9 @@ MipsTargetLowering(MipsTargetMachine &TM): TargetLowering(TM)
setOperationAction(ISD::BR_JT, MVT::Other, Expand);
setOperationAction(ISD::BR_CC, MVT::Other, Expand);
setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
setOperationAction(ISD::SELECT_CC, MVT::i32, Expand);
setOperationAction(ISD::SELECT, MVT::i32, Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
setOperationAction(ISD::SELECT, MVT::i32, Expand);
// Mips not supported intrinsics.
setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
@ -224,7 +225,7 @@ LowerCCCCallTo(SDOperand Op, SelectionDAG &DAG, unsigned CC)
// To meet ABI, Mips must always allocate 16 bytes on
// the stack (even if less than 4 are used as arguments)
int VTsize = MVT::getSizeInBits(MVT::i32)/8;
MFI->CreateFixedObject(VTsize, -(VTsize*3));
MFI->CreateFixedObject(VTsize, (VTsize*3));
CCInfo.AnalyzeCallOperands(Op.Val, CC_Mips);
@ -272,10 +273,10 @@ LowerCCCCallTo(SDOperand Op, SelectionDAG &DAG, unsigned CC)
StackPtr = DAG.getRegister(StackReg, getPointerTy());
// Create the frame index object for this incoming parameter
// This guarantees that when allocating Local Area our room
// will not be overwritten.
// This guarantees that when allocating Local Area the firsts
// 16 bytes which are alwayes reserved won't be overwritten.
int FI = MFI->CreateFixedObject(MVT::getSizeInBits(VA.getValVT())/8,
-(16 + VA.getLocMemOffset()) );
(16 + VA.getLocMemOffset()));
SDOperand PtrOff = DAG.getFrameIndex(FI,getPointerTy());
@ -364,10 +365,6 @@ LowerCallResult(SDOperand Chain, SDOperand InFlag, SDNode *TheCall,
CCInfo.AnalyzeCallResult(TheCall, RetCC_Mips);
SmallVector<SDOperand, 8> ResultVals;
// Returns void
//if (!RVLocs.size())
// return Chain.Val;
// Copy all of the result registers out of their specified physreg.
for (unsigned i = 0; i != RVLocs.size(); ++i) {
Chain = DAG.getCopyFromReg(Chain, RVLocs[i].getLocReg(),
@ -410,6 +407,7 @@ LowerCCCArguments(SDOperand Op, SelectionDAG &DAG)
SDOperand Root = Op.getOperand(0);
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
bool isVarArg = cast<ConstantSDNode>(Op.getOperand(2))->getValue() != 0;
unsigned CC = DAG.getMachineFunction().getFunction()->getCallingConv();
@ -437,7 +435,6 @@ LowerCCCArguments(SDOperand Op, SelectionDAG &DAG)
RC = Mips::CPURegsRegisterClass;
else
assert(0 && "support only Mips::CPURegsRegisterClass");
// Transform the arguments stored on
// physical registers into virtual ones
@ -460,17 +457,22 @@ LowerCCCArguments(SDOperand Op, SelectionDAG &DAG)
ArgValues.push_back(ArgValue);
// To meet ABI, when VARARGS are passed on registers, the registers
// containt must be written to the their always reserved home location
// on the stack.
// must have their values written to the caller stack frame.
if (isVarArg) {
if (StackPtr.Val == 0)
StackPtr = DAG.getRegister(StackReg, getPointerTy());
// Create the frame index object for this incoming parameter
// The first 16 bytes are reserved.
int FI = MFI->CreateFixedObject(MVT::getSizeInBits(VA.getValVT())/8,
i*4);
// The stack pointer offset is relative to the caller stack frame.
// Since the real stack size is unknown here, a negative SPOffset
// is used so there's a way to adjust these offsets when the stack
// size get known (on EliminateFrameIndex). A dummy SPOffset is
// used instead of a direct negative address (which is recorded to
// be used on emitPrologue) to avoid mis-calc of the first stack
// offset on PEI::calculateFrameObjectOffsets.
// Arguments are always 32-bit.
int FI = MFI->CreateFixedObject(4, 0);
MipsFI->recordStoreVarArgsFI(FI, -(4+(i*4)));
SDOperand PtrOff = DAG.getFrameIndex(FI, getPointerTy());
// emit ISD::STORE whichs stores the
@ -482,9 +484,16 @@ LowerCCCArguments(SDOperand Op, SelectionDAG &DAG)
// sanity check
assert(VA.isMemLoc());
// Create the frame index object for this incoming parameter...
int FI = MFI->CreateFixedObject(MVT::getSizeInBits(VA.getValVT())/8,
(16 + VA.getLocMemOffset()));
// The stack pointer offset is relative to the caller stack frame.
// Since the real stack size is unknown here, a negative SPOffset
// is used so there's a way to adjust these offsets when the stack
// size get known (on EliminateFrameIndex). A dummy SPOffset is
// used instead of a direct negative address (which is recorded to
// be used on emitPrologue) to avoid mis-calc of the first stack
// offset on PEI::calculateFrameObjectOffsets.
// Arguments are always 32-bit.
int FI = MFI->CreateFixedObject(4, 0);
MipsFI->recordLoadArgsFI(FI, -(4+(16+VA.getLocMemOffset())));
// Create load nodes to retrieve arguments from the stack
SDOperand FIN = DAG.getFrameIndex(FI, getPointerTy());