From 868cf82c683dac3ceaf02ad6039daf5e6d71c1a3 Mon Sep 17 00:00:00 2001 From: Ruchira Sasanka Date: Fri, 9 Nov 2001 23:49:14 +0000 Subject: [PATCH] Added code for correct reordering of call arguments git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1234 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/SparcV9/SparcV9Internals.h | 4 + lib/Target/SparcV9/SparcV9RegInfo.cpp | 239 +++++++++++++++++++++++++- 2 files changed, 240 insertions(+), 3 deletions(-) diff --git a/lib/Target/SparcV9/SparcV9Internals.h b/lib/Target/SparcV9/SparcV9Internals.h index f8707c2d521..ad04eb3ee73 100644 --- a/lib/Target/SparcV9/SparcV9Internals.h +++ b/lib/Target/SparcV9/SparcV9Internals.h @@ -284,6 +284,10 @@ class UltraSparcRegInfo : public MachineRegInfo MachineInstr * cpCCR2IntMI(const unsigned IntReg) const; MachineInstr * cpInt2CCRMI(const unsigned IntReg) const; + void OrderAddedInstrns( vector &UnordVec, + vector &OrdVec) const; + + public: diff --git a/lib/Target/SparcV9/SparcV9RegInfo.cpp b/lib/Target/SparcV9/SparcV9RegInfo.cpp index 4d581f7914f..fed83a90051 100644 --- a/lib/Target/SparcV9/SparcV9RegInfo.cpp +++ b/lib/Target/SparcV9/SparcV9RegInfo.cpp @@ -590,6 +590,8 @@ void UltraSparcRegInfo::colorCallArgs(const MachineInstr *const CallMI, // Now color all args of the call instruction + vector AddedInstrnsBefore; + unsigned NumOfCallArgs = getCallInstNumArgs( CallMI ); for(unsigned argNo=0, i=0; i < NumOfCallArgs; ++i, ++argNo ) { @@ -666,7 +668,7 @@ void UltraSparcRegInfo::colorCallArgs(const MachineInstr *const CallMI, AdMI = cpReg2MemMI(UniLRReg, getStackPointer(), argOffset, RegType ); } - CallAI->InstrnsBefore.push_back( AdMI ); // Now add the instruction + AddedInstrnsBefore.push_back( AdMI ); // Now add the instruction } else { // LR is not colored (i.e., spilled) @@ -681,7 +683,7 @@ void UltraSparcRegInfo::colorCallArgs(const MachineInstr *const CallMI, AdMI = cpMem2RegMI(getFramePointer(), LR->getSpillOffFromFP(), UniArgReg, RegType ); - CallAI->InstrnsBefore.push_back( AdMI ); // Now add the instruction + AddedInstrnsBefore.push_back( AdMI ); // Now add the instruction } else { @@ -696,6 +698,7 @@ void UltraSparcRegInfo::colorCallArgs(const MachineInstr *const CallMI, // above method since we cannot find LVSetBefore without the BB int TReg = PRA.getRegNotUsedByThisInst( LR->getRegClass(), CallMI ); + int TmpOff = PRA.mcInfo.pushTempValue(target, target.findOptimalStorageSize(LR->getType())); // getStackOffsets().getNewTmpPosOffFromFP(); @@ -715,19 +718,51 @@ void UltraSparcRegInfo::colorCallArgs(const MachineInstr *const CallMI, TReg, RegType ); Ad3 = cpReg2MemMI(TReg, getStackPointer(), argOffset, RegType ); Ad4 = cpMem2RegMI(getFramePointer(), TmpOff, TReg, RegType ); + + // We directly add to CallAI->InstrnsBefore instead of adding to + // AddedInstrnsBefore since these instructions must not be + // reordered. CallAI->InstrnsBefore.push_back( Ad1 ); CallAI->InstrnsBefore.push_back( Ad2 ); CallAI->InstrnsBefore.push_back( Ad3 ); CallAI->InstrnsBefore.push_back( Ad4 ); + + cerr << "\n Caution: Call arg moved from stack to stack"; } } } // for each parameter in call instruction + + // if we added any instruction before the call instruction, verify + // that they are in the proper order and if not, reorder them + + if( ! AddedInstrnsBefore.empty() ) { + + if( DEBUG_RA) { + cerr << "\nCalling reorder with instrns: \n"; + for(unsigned i=0; i < AddedInstrnsBefore.size(); i++) + cerr << *(AddedInstrnsBefore[i]); + } + + vector TmpVec; + OrderAddedInstrns(AddedInstrnsBefore, TmpVec); + + if( DEBUG_RA) { + cerr << "\nAfter reordering instrns: \n"; + for(unsigned i=0; i < TmpVec.size(); i++) + cerr << *(TmpVec[i]); + } + + // copy the results back from TmpVec to InstrnsBefore + for(unsigned i=0; i < TmpVec.size(); i++) + CallAI->InstrnsBefore.push_back( TmpVec[i] ); + } + + // Reset optional args area again to be safe - // PRA.mcInfo.resetOptionalArgs(target); @@ -1265,3 +1300,201 @@ void UltraSparcRegInfo::printReg(const LiveRange *const LR) { cerr << "]" << endl; } } + +//--------------------------------------------------------------------------- +// This method examines instructions inserted by RegAlloc code before a +// machine instruction to detect invalid orders that destroy values before +// they are used. If it detects such conditions, it reorders the instructions. +// +// The unordered instructions come in the UnordVec. These instructions are +// instructions inserted by RegAlloc. All suhc instruction MUST have +// their USES BEFORE THE DEFS. + +// The UnordVec & OrdVec must be DISTINCT. The OrdVec must be empty when +// this method is called. + +// This method uses two vectors for efficiency in accessing + +//--------------------------------------------------------------------------- +void UltraSparcRegInfo::OrderAddedInstrns( vector &UnordVec, + vector &OrdVec) const{ + + /* + Problem: We can have instructions inserted by RegAlloc like + 1. add %ox %g0 %oy + 2. add %oy %g0 %oz, where z!=x or z==x + + This is wrong since %oy used by 2 is overwritten by 1 + */ + + /* Algorithm: + + Round 1: + For each instruction 'Inst' in UnordVec, starting from UnordVec.begin, + let Def be the destination reg of instr. + For each use 'Use' of the following instruction + If Def==Use continue + If no use is found, push back 'Inst' to OrdVec + + If no inst is left in UnordVec by the end of Round1, return + + Round 2: + For each inst 'Inst' left in UnordVec + For each use 'Use' in Inst + If threre is NO Def for this Use in an inst in OrdVec + push back Inst + Else + push_front a stack save instr mem location "Loc" + push_back a restore inst to load to Use from Loc + discard Inst (assert that one operand is %g0) + + */ + + bool CouldMoveAll = true; + + + vector::iterator DefIt = UnordVec.begin(); + + for( ; DefIt != UnordVec.end(); ++DefIt ) { + + // for each instruction in the UnordVec do ... + + MachineInstr *DefInst = *DefIt; + + // cerr << "\nDefInst = " << *DefInst; + + for(unsigned OpNumD=0; OpNumD < DefInst->getNumOperands(); ++OpNumD) { + + MachineOperand& DefOp = DefInst->getOperand(OpNumD); + + if( DefOp.opIsDef() && + DefOp.getOperandType() == MachineOperand::MO_MachineRegister) { + + // If the operand in DefInst is a def ... + + bool DefEqUse = false; + + vector::iterator UseIt = DefIt; + UseIt++; + + for( ; UseIt != UnordVec.end(); ++UseIt ) { + + // for each inst (UseInst) that is below the DefInst do ... + + MachineInstr *UseInst = *UseIt; + + for(unsigned OpNumU=0; OpNumU < UseInst->getNumOperands(); ++OpNumU){ + + MachineOperand& UseOp = UseInst->getOperand(OpNumU); + + if( ! UseOp.opIsDef() && + UseOp.getOperandType() == MachineOperand::MO_MachineRegister) { + + // if use is a register ... + + if( DefOp.getMachineRegNum() == UseOp.getMachineRegNum() ) { + + // if Def and this use are the same, it means that this use + // is destroyed by a def before it is used + + DefEqUse = true; + CouldMoveAll = false; + + cerr << "\nReordered Ins (Moved up): " << *UseInst; + break; + + } // if two registers are equal + + } // if use is a register + + } // for all uses + + }// for all use instructions + + if( ! DefEqUse ) { + // cerr << "\nMoved Inst = " << *DefInst; + OrdVec.push_back(DefInst); + *DefIt = NULL; + } + else + break; // exit the loop since we can't move DefInst + + } // if Def is a machine register + + } // for all Defs in DefInst (there should be only 1) + + } // for all instructions in the UnordVec + + + if( CouldMoveAll ) { + assert( (UnordVec.size() == OrdVec.size()) && + "Different Vec Sizes after reordering"); + return; + } + + + // We are here because there were two instructions like: + // 1. add %ox %g0 %oy + // 2. add %oy %g0 %oz, where z!=x or z==x + // and hence we could not move 1 to the OrdVec + + // cerr << "\nCaution: Added instructions will be RE-ORDERED !@!@!"; + + vector< MachineInstr *>::iterator UnordIt = UnordVec.begin(); + + for( ; UnordIt != UnordVec.end(); ++UnordIt ) { + + MachineInstr *UnordInst = *UnordIt; + if( UnordInst == NULL ) continue; + + for(unsigned OpNumU=0; OpNumU < UnordInst->getNumOperands(); ++OpNumU) { + + MachineOperand& UseOp = UnordInst->getOperand(OpNumU); + + if( ! UseOp.opIsDef() && + UseOp.getOperandType() == MachineOperand::MO_MachineRegister) { + + if( UseOp.getMachineRegNum() == getZeroRegNum() ) + continue; + + // for all uses of UnordInst + bool DefEqUse = false; + + vector::iterator OrdIt = OrdVec.begin(); + + for( ; OrdIt != OrdVec.end(); ++OrdIt ) { + + MachineInstr *OrdInst = *OrdIt ; + + for(unsigned OpNumO=0; OpNumO < OrdInst->getNumOperands(); ++OpNumO){ + + MachineOperand& DefOp = OrdInst->getOperand(OpNumO); + + if( DefOp.opIsDef() && + DefOp.getOperandType() == MachineOperand::MO_MachineRegister) { + + if( DefOp.getMachineRegNum() == UseOp.getMachineRegNum() ) { + + DefEqUse = true; + assert(0 && "Insert save/restre code for reordering"); + + } // if two registers are equal + + } // if Def is a register + + } // for all defs + + } // for each instr in OrdVec + + if( !DefEqUse ) { + OrdVec.push_back( UnordInst ); + cerr << "\nReordered instr (Moved Down): " << *UnordInst; + } + + } // if the operand in UnordInst is a use + + } // for each use in the UnordInst + + } // for each UnordInst in UnordVec + +} -- 2.34.1