Add code to support stack spill/temp offsets that don't fit in the

immed. field.  Moved insertCallerSavingCode() to PhyRegAlloc: it is
now machine independent.  Remove all uses of PhyRegAlloc.

llvm-svn: 7391
This commit is contained in:
Vikram S. Adve 2003-07-29 19:53:21 +00:00
parent 9143f1962e
commit 2353584afc
1 changed files with 99 additions and 238 deletions
llvm/lib/Target/Sparc

View File

@ -9,13 +9,11 @@
#include "SparcRegClassInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionInfo.h"
#include "llvm/CodeGen/PhyRegAlloc.h"
#include "llvm/CodeGen/InstrSelection.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineCodeForInstruction.h"
#include "llvm/CodeGen/MachineInstrAnnot.h"
#include "llvm/CodeGen/FunctionLiveVarInfo.h" // FIXME: Remove
#include "../../CodeGen/RegAlloc/RegAllocCommon.h" // FIXME!
#include "llvm/CodeGen/LiveRangeInfo.h"
#include "llvm/iTerminators.h"
#include "llvm/iOther.h"
#include "llvm/Function.h"
@ -387,7 +385,8 @@ void UltraSparcRegInfo::suggestRegs4MethodArgs(const Function *Meth,
//---------------------------------------------------------------------------
void UltraSparcRegInfo::colorMethodArgs(const Function *Meth,
LiveRangeInfo &LRI,
AddedInstrns *FirstAI) const {
std::vector<MachineInstr*>& InstrnsBefore,
std::vector<MachineInstr*>& InstrnsAfter) const {
// check if this is a varArgs function. needed for choosing regs.
bool isVarArgs = isVarArgsFunction(Meth->getType());
@ -454,14 +453,14 @@ void UltraSparcRegInfo::colorMethodArgs(const Function *Meth,
int TmpOff = MachineFunction::get(Meth).getInfo()->pushTempValue(
getSpilledRegSize(regType));
cpReg2MemMI(FirstAI->InstrnsBefore,
cpReg2MemMI(InstrnsBefore,
UniArgReg, getFramePointer(), TmpOff, IntRegType);
cpMem2RegMI(FirstAI->InstrnsBefore,
cpMem2RegMI(InstrnsBefore,
getFramePointer(), TmpOff, UniLRReg, regType);
}
else {
cpReg2RegMI(FirstAI->InstrnsBefore, UniArgReg, UniLRReg, regType);
cpReg2RegMI(InstrnsBefore, UniArgReg, UniLRReg, regType);
}
}
else {
@ -484,7 +483,7 @@ void UltraSparcRegInfo::colorMethodArgs(const Function *Meth,
offsetFromFP += slotSize - argSize;
}
cpMem2RegMI(FirstAI->InstrnsBefore,
cpMem2RegMI(InstrnsBefore,
getFramePointer(), offsetFromFP, UniLRReg, regType);
}
@ -510,11 +509,11 @@ void UltraSparcRegInfo::colorMethodArgs(const Function *Meth,
assert(isVarArgs && regClassIDOfArgReg == IntRegClassID &&
"This should only be an Int register for an FP argument");
cpReg2MemMI(FirstAI->InstrnsBefore, UniArgReg,
cpReg2MemMI(InstrnsBefore, UniArgReg,
getFramePointer(), LR->getSpillOffFromFP(), IntRegType);
}
else {
cpReg2MemMI(FirstAI->InstrnsBefore, UniArgReg,
cpReg2MemMI(InstrnsBefore, UniArgReg,
getFramePointer(), LR->getSpillOffFromFP(), regType);
}
}
@ -736,27 +735,51 @@ UltraSparcRegInfo::cpReg2RegMI(std::vector<MachineInstr*>& mvec,
void
UltraSparcRegInfo::cpReg2MemMI(std::vector<MachineInstr*>& mvec,
unsigned SrcReg,
unsigned DestPtrReg,
unsigned PtrReg,
int Offset, int RegType,
int scratchReg) const {
MachineInstr * MI = NULL;
int OffReg = -1;
// If the Offset will not fit in the signed-immediate field, find an
// unused register to hold the offset value. This takes advantage of
// the fact that all the opcodes used below have the same size immed. field.
// Use the register allocator, PRA, to find an unused reg. at this MI.
//
if (RegType != IntCCRegType) // does not use offset below
if (! target.getInstrInfo().constantFitsInImmedField(V9::LDXi, Offset)) {
#ifdef CAN_FIND_FREE_REGISTER_TRANSPARENTLY
RegClass* RC = PRA.getRegClassByID(this->getRegClassIDOfRegType(RegType));
OffReg = PRA.getUnusedUniRegAtMI(RC, RegType, MInst, LVSetBef);
#else
// Default to using register g2 for holding large offsets
OffReg = getUnifiedRegNum(UltraSparcRegInfo::IntRegClassID,
SparcIntRegClass::g4);
#endif
assert(OffReg >= 0 && "FIXME: cpReg2MemMI cannot find an unused reg.");
mvec.push_back(BuildMI(V9::SETSW, 2).addZImm(Offset).addReg(OffReg));
}
switch (RegType) {
case IntRegType:
assert(target.getInstrInfo().constantFitsInImmedField(V9::STXi, Offset));
MI = BuildMI(V9::STXi,3).addMReg(SrcReg).addMReg(DestPtrReg)
.addSImm(Offset);
if (target.getInstrInfo().constantFitsInImmedField(V9::STXi, Offset))
MI = BuildMI(V9::STXi,3).addMReg(SrcReg).addMReg(PtrReg).addSImm(Offset);
else
MI = BuildMI(V9::STXr,3).addMReg(SrcReg).addMReg(PtrReg).addMReg(OffReg);
break;
case FPSingleRegType:
assert(target.getInstrInfo().constantFitsInImmedField(V9::STFi, Offset));
MI = BuildMI(V9::STFi, 3).addMReg(SrcReg).addMReg(DestPtrReg)
.addSImm(Offset);
if (target.getInstrInfo().constantFitsInImmedField(V9::STFi, Offset))
MI = BuildMI(V9::STFi, 3).addMReg(SrcReg).addMReg(PtrReg).addSImm(Offset);
else
MI = BuildMI(V9::STFr, 3).addMReg(SrcReg).addMReg(PtrReg).addMReg(OffReg);
break;
case FPDoubleRegType:
assert(target.getInstrInfo().constantFitsInImmedField(V9::STDFi, Offset));
MI = BuildMI(V9::STDFi,3).addMReg(SrcReg).addMReg(DestPtrReg)
.addSImm(Offset);
if (target.getInstrInfo().constantFitsInImmedField(V9::STDFi, Offset))
MI = BuildMI(V9::STDFi,3).addMReg(SrcReg).addMReg(PtrReg).addSImm(Offset);
else
MI = BuildMI(V9::STDFr,3).addMReg(SrcReg).addMReg(PtrReg).addSImm(OffReg);
break;
case IntCCRegType:
@ -768,15 +791,16 @@ UltraSparcRegInfo::cpReg2MemMI(std::vector<MachineInstr*>& mvec,
.addMReg(scratchReg, MOTy::Def));
mvec.push_back(MI);
cpReg2MemMI(mvec, scratchReg, DestPtrReg, Offset, IntRegType);
cpReg2MemMI(mvec, scratchReg, PtrReg, Offset, IntRegType);
return;
case FloatCCRegType: {
assert(target.getInstrInfo().constantFitsInImmedField(V9::STXFSRi, Offset));
unsigned fsrRegNum = getUnifiedRegNum(UltraSparcRegInfo::SpecialRegClassID,
unsigned fsrReg = getUnifiedRegNum(UltraSparcRegInfo::SpecialRegClassID,
SparcSpecialRegClass::fsr);
MI = BuildMI(V9::STXFSRi, 3)
.addMReg(fsrRegNum).addMReg(DestPtrReg).addSImm(Offset);
if (target.getInstrInfo().constantFitsInImmedField(V9::STXFSRi, Offset))
MI=BuildMI(V9::STXFSRi,3).addMReg(fsrReg).addMReg(PtrReg).addSImm(Offset);
else
MI=BuildMI(V9::STXFSRr,3).addMReg(fsrReg).addMReg(PtrReg).addMReg(OffReg);
break;
}
default:
@ -794,35 +818,65 @@ UltraSparcRegInfo::cpReg2MemMI(std::vector<MachineInstr*>& mvec,
void
UltraSparcRegInfo::cpMem2RegMI(std::vector<MachineInstr*>& mvec,
unsigned SrcPtrReg,
unsigned PtrReg,
int Offset,
unsigned DestReg,
int RegType,
int scratchReg) const {
MachineInstr * MI = NULL;
int OffReg = -1;
// If the Offset will not fit in the signed-immediate field, find an
// unused register to hold the offset value. This takes advantage of
// the fact that all the opcodes used below have the same size immed. field.
// Use the register allocator, PRA, to find an unused reg. at this MI.
//
if (RegType != IntCCRegType) // does not use offset below
if (! target.getInstrInfo().constantFitsInImmedField(V9::LDXi, Offset)) {
#ifdef CAN_FIND_FREE_REGISTER_TRANSPARENTLY
RegClass* RC = PRA.getRegClassByID(this->getRegClassIDOfRegType(RegType));
OffReg = PRA.getUnusedUniRegAtMI(RC, RegType, MInst, LVSetBef);
#else
// Default to using register g2 for holding large offsets
OffReg = getUnifiedRegNum(UltraSparcRegInfo::IntRegClassID,
SparcIntRegClass::g4);
#endif
assert(OffReg >= 0 && "FIXME: cpReg2MemMI cannot find an unused reg.");
mvec.push_back(BuildMI(V9::SETSW, 2).addZImm(Offset).addReg(OffReg));
}
switch (RegType) {
case IntRegType:
assert(target.getInstrInfo().constantFitsInImmedField(V9::LDXi, Offset));
MI = BuildMI(V9::LDXi, 3).addMReg(SrcPtrReg).addSImm(Offset)
.addMReg(DestReg, MOTy::Def);
if (target.getInstrInfo().constantFitsInImmedField(V9::LDXi, Offset))
MI = BuildMI(V9::LDXi, 3).addMReg(PtrReg).addSImm(Offset).addMReg(DestReg,
MOTy::Def);
else
MI = BuildMI(V9::LDXr, 3).addMReg(PtrReg).addMReg(OffReg).addMReg(DestReg,
MOTy::Def);
break;
case FPSingleRegType:
assert(target.getInstrInfo().constantFitsInImmedField(V9::LDFi, Offset));
MI = BuildMI(V9::LDFi, 3).addMReg(SrcPtrReg).addSImm(Offset)
.addMReg(DestReg, MOTy::Def);
if (target.getInstrInfo().constantFitsInImmedField(V9::LDFi, Offset))
MI = BuildMI(V9::LDFi, 3).addMReg(PtrReg).addSImm(Offset).addMReg(DestReg,
MOTy::Def);
else
MI = BuildMI(V9::LDFr, 3).addMReg(PtrReg).addMReg(OffReg).addMReg(DestReg,
MOTy::Def);
break;
case FPDoubleRegType:
assert(target.getInstrInfo().constantFitsInImmedField(V9::LDDFi, Offset));
MI = BuildMI(V9::LDDFi, 3).addMReg(SrcPtrReg).addSImm(Offset)
.addMReg(DestReg, MOTy::Def);
if (target.getInstrInfo().constantFitsInImmedField(V9::LDDFi, Offset))
MI= BuildMI(V9::LDDFi, 3).addMReg(PtrReg).addSImm(Offset).addMReg(DestReg,
MOTy::Def);
else
MI= BuildMI(V9::LDDFr, 3).addMReg(PtrReg).addMReg(OffReg).addMReg(DestReg,
MOTy::Def);
break;
case IntCCRegType:
assert(scratchReg >= 0 && "Need scratch reg to load %ccr from memory");
assert(getRegType(scratchReg) ==IntRegType && "Invalid scratch reg");
cpMem2RegMI(mvec, SrcPtrReg, Offset, scratchReg, IntRegType);
cpMem2RegMI(mvec, PtrReg, Offset, scratchReg, IntRegType);
MI = (BuildMI(V9::WRCCRr, 3)
.addMReg(scratchReg)
.addMReg(SparcIntRegClass::g0)
@ -831,10 +885,13 @@ UltraSparcRegInfo::cpMem2RegMI(std::vector<MachineInstr*>& mvec,
break;
case FloatCCRegType: {
assert(target.getInstrInfo().constantFitsInImmedField(V9::LDXFSRi, Offset));
unsigned fsrRegNum = getUnifiedRegNum(UltraSparcRegInfo::SpecialRegClassID,
SparcSpecialRegClass::fsr);
MI = BuildMI(V9::LDXFSRi, 3).addMReg(SrcPtrReg).addSImm(Offset)
if (target.getInstrInfo().constantFitsInImmedField(V9::LDXFSRi, Offset))
MI = BuildMI(V9::LDXFSRi, 3).addMReg(PtrReg).addSImm(Offset)
.addMReg(fsrRegNum, MOTy::UseAndDef);
else
MI = BuildMI(V9::LDXFSRr, 3).addMReg(PtrReg).addMReg(OffReg)
.addMReg(fsrRegNum, MOTy::UseAndDef);
break;
}
@ -877,202 +934,6 @@ UltraSparcRegInfo::cpValue2Value(Value *Src, Value *Dest,
//----------------------------------------------------------------------------
// This method inserts caller saving/restoring instructons before/after
// a call machine instruction. The caller saving/restoring instructions are
// inserted like:
//
// ** caller saving instructions
// other instructions inserted for the call by ColorCallArg
// CALL instruction
// other instructions inserted for the call ColorCallArg
// ** caller restoring instructions
//
//----------------------------------------------------------------------------
void
UltraSparcRegInfo::insertCallerSavingCode
(std::vector<MachineInstr*> &instrnsBefore,
std::vector<MachineInstr*> &instrnsAfter,
MachineInstr *CallMI,
const BasicBlock *BB,
PhyRegAlloc &PRA) const
{
assert(target.getInstrInfo().isCall(CallMI->getOpCode()));
// has set to record which registers were saved/restored
//
hash_set<unsigned> PushedRegSet;
CallArgsDescriptor* argDesc = CallArgsDescriptor::get(CallMI);
// if the call is to a instrumentation function, do not insert save and
// restore instructions the instrumentation function takes care of save
// restore for volatile regs.
//
// FIXME: this should be made general, not specific to the reoptimizer!
//
const Function *Callee = argDesc->getCallInst()->getCalledFunction();
bool isLLVMFirstTrigger = Callee && Callee->getName() == "llvm_first_trigger";
// Now check if the call has a return value (using argDesc) and if so,
// find the LR of the TmpInstruction representing the return value register.
// (using the last or second-last *implicit operand* of the call MI).
// Insert it to to the PushedRegSet since we must not save that register
// and restore it after the call.
// We do this because, we look at the LV set *after* the instruction
// to determine, which LRs must be saved across calls. The return value
// of the call is live in this set - but we must not save/restore it.
//
if (const Value *origRetVal = argDesc->getReturnValue()) {
unsigned retValRefNum = (CallMI->getNumImplicitRefs() -
(argDesc->getIndirectFuncPtr()? 1 : 2));
const TmpInstruction* tmpRetVal =
cast<TmpInstruction>(CallMI->getImplicitRef(retValRefNum));
assert(tmpRetVal->getOperand(0) == origRetVal &&
tmpRetVal->getType() == origRetVal->getType() &&
"Wrong implicit ref?");
LiveRange *RetValLR = PRA.LRI.getLiveRangeForValue( tmpRetVal );
assert(RetValLR && "No LR for RetValue of call");
if (! RetValLR->isMarkedForSpill())
PushedRegSet.insert(getUnifiedRegNum(RetValLR->getRegClassID(),
RetValLR->getColor()));
}
const ValueSet &LVSetAft = PRA.LVI->getLiveVarSetAfterMInst(CallMI, BB);
ValueSet::const_iterator LIt = LVSetAft.begin();
// for each live var in live variable set after machine inst
for( ; LIt != LVSetAft.end(); ++LIt) {
// get the live range corresponding to live var
LiveRange *const LR = PRA.LRI.getLiveRangeForValue(*LIt );
// LR can be null if it is a const since a const
// doesn't have a dominating def - see Assumptions above
if( LR ) {
if(! LR->isMarkedForSpill()) {
assert(LR->hasColor() && "LR is neither spilled nor colored?");
unsigned RCID = LR->getRegClassID();
unsigned Color = LR->getColor();
if ( isRegVolatile(RCID, Color) ) {
//if the function is special LLVM function,
//And the register is not modified by call, don't save and restore
if(isLLVMFirstTrigger && !modifiedByCall(RCID, Color))
continue;
// if the value is in both LV sets (i.e., live before and after
// the call machine instruction)
unsigned Reg = getUnifiedRegNum(RCID, Color);
if( PushedRegSet.find(Reg) == PushedRegSet.end() ) {
// if we haven't already pushed that register
unsigned RegType = getRegTypeForLR(LR);
// Now get two instructions - to push on stack and pop from stack
// and add them to InstrnsBefore and InstrnsAfter of the
// call instruction
//
int StackOff =
PRA.MF.getInfo()->pushTempValue(getSpilledRegSize(RegType));
//---- Insert code for pushing the reg on stack ----------
std::vector<MachineInstr*> AdIBef, AdIAft;
// We may need a scratch register to copy the saved value
// to/from memory. This may itself have to insert code to
// free up a scratch register. Any such code should go before
// the save code. The scratch register, if any, is by default
// temporary and not "used" by the instruction unless the
// copy code itself decides to keep the value in the scratch reg.
int scratchRegType = -1;
int scratchReg = -1;
if (regTypeNeedsScratchReg(RegType, scratchRegType))
{ // Find a register not live in the LVSet before CallMI
const ValueSet &LVSetBef =
PRA.LVI->getLiveVarSetBeforeMInst(CallMI, BB);
scratchReg = PRA.getUsableUniRegAtMI(scratchRegType, &LVSetBef,
CallMI, AdIBef, AdIAft);
assert(scratchReg != getInvalidRegNum());
}
if (AdIBef.size() > 0)
instrnsBefore.insert(instrnsBefore.end(),
AdIBef.begin(), AdIBef.end());
cpReg2MemMI(instrnsBefore, Reg,getFramePointer(),StackOff,RegType,
scratchReg);
if (AdIAft.size() > 0)
instrnsBefore.insert(instrnsBefore.end(),
AdIAft.begin(), AdIAft.end());
//---- Insert code for popping the reg from the stack ----------
AdIBef.clear();
AdIAft.clear();
// We may need a scratch register to copy the saved value
// from memory. This may itself have to insert code to
// free up a scratch register. Any such code should go
// after the save code. As above, scratch is not marked "used".
//
scratchRegType = -1;
scratchReg = -1;
if (regTypeNeedsScratchReg(RegType, scratchRegType))
{ // Find a register not live in the LVSet after CallMI
scratchReg = PRA.getUsableUniRegAtMI(scratchRegType, &LVSetAft,
CallMI, AdIBef, AdIAft);
assert(scratchReg != getInvalidRegNum());
}
if (AdIBef.size() > 0)
instrnsAfter.insert(instrnsAfter.end(),
AdIBef.begin(), AdIBef.end());
cpMem2RegMI(instrnsAfter, getFramePointer(), StackOff,Reg,RegType,
scratchReg);
if (AdIAft.size() > 0)
instrnsAfter.insert(instrnsAfter.end(),
AdIAft.begin(), AdIAft.end());
PushedRegSet.insert(Reg);
if(DEBUG_RA) {
std::cerr << "\nFor call inst:" << *CallMI;
std::cerr << " -inserted caller saving instrs: Before:\n\t ";
for_each(instrnsBefore.begin(), instrnsBefore.end(),
std::mem_fun(&MachineInstr::dump));
std::cerr << " -and After:\n\t ";
for_each(instrnsAfter.begin(), instrnsAfter.end(),
std::mem_fun(&MachineInstr::dump));
}
} // if not already pushed
} // if LR has a volatile color
} // if LR has color
} // if there is a LR for Var
} // for each value in the LV set after instruction
}
//---------------------------------------------------------------------------
// Print the register assigned to a LR
//---------------------------------------------------------------------------