Fix fallout in CodeGenPrepare from 56526. Will likely need more work.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56546 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eric Christopher 2008-09-24 05:32:41 +00:00
parent 2a5196fe67
commit 692bf6b85e

View File

@ -35,7 +35,7 @@
#include "llvm/Support/GetElementPtrTypeIterator.h"
using namespace llvm;
namespace {
namespace {
class VISIBILITY_HIDDEN CodeGenPrepare : public FunctionPass {
/// TLI - Keep a pointer of a TargetLowering to consult for determining
/// transformation profitability.
@ -45,7 +45,7 @@ namespace {
explicit CodeGenPrepare(const TargetLowering *tli = 0)
: FunctionPass(&ID), TLI(tli) {}
bool runOnFunction(Function &F);
private:
bool EliminateMostlyEmptyBlocks(Function &F);
bool CanMergeBlocks(const BasicBlock *BB, const BasicBlock *DestBB) const;
@ -71,11 +71,11 @@ FunctionPass *llvm::createCodeGenPreparePass(const TargetLowering *TLI) {
bool CodeGenPrepare::runOnFunction(Function &F) {
bool EverMadeChange = false;
// First pass, eliminate blocks that contain only PHI nodes and an
// unconditional branch.
EverMadeChange |= EliminateMostlyEmptyBlocks(F);
bool MadeChange = true;
while (MadeChange) {
MadeChange = false;
@ -87,7 +87,7 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
}
/// EliminateMostlyEmptyBlocks - eliminate blocks that contain only PHI nodes
/// and an unconditional branch. Passes before isel (e.g. LSR/loopsimplify)
/// and an unconditional branch. Passes before isel (e.g. LSR/loopsimplify)
/// often split edges in ways that are non-optimal for isel. Start by
/// eliminating these blocks so we can split them the way we want them.
bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) {
@ -100,7 +100,7 @@ bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) {
BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator());
if (!BI || !BI->isUnconditional())
continue;
// If the instruction before the branch isn't a phi node, then other stuff
// is happening here.
BasicBlock::iterator BBI = BI;
@ -108,15 +108,15 @@ bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) {
--BBI;
if (!isa<PHINode>(BBI)) continue;
}
// Do not break infinite loops.
BasicBlock *DestBB = BI->getSuccessor(0);
if (DestBB == BB)
continue;
if (!CanMergeBlocks(BB, DestBB))
continue;
EliminateMostlyEmptyBlock(BB);
MadeChange = true;
}
@ -138,8 +138,8 @@ bool CodeGenPrepare::CanMergeBlocks(const BasicBlock *BB,
const Instruction *User = cast<Instruction>(*UI);
if (User->getParent() != DestBB || !isa<PHINode>(User))
return false;
// If User is inside DestBB block and it is a PHINode then check
// incoming value. If incoming value is not from BB then this is
// If User is inside DestBB block and it is a PHINode then check
// incoming value. If incoming value is not from BB then this is
// a complex condition (e.g. preheaders) we want to avoid here.
if (User->getParent() == DestBB) {
if (const PHINode *UPN = dyn_cast<PHINode>(User))
@ -152,13 +152,13 @@ bool CodeGenPrepare::CanMergeBlocks(const BasicBlock *BB,
}
}
}
// If BB and DestBB contain any common predecessors, then the phi nodes in BB
// and DestBB may have conflicting incoming values for the block. If so, we
// can't merge the block.
const PHINode *DestBBPN = dyn_cast<PHINode>(DestBB->begin());
if (!DestBBPN) return true; // no conflict.
// Collect the preds of BB.
SmallPtrSet<const BasicBlock*, 16> BBPreds;
if (const PHINode *BBPN = dyn_cast<PHINode>(BB->begin())) {
@ -168,7 +168,7 @@ bool CodeGenPrepare::CanMergeBlocks(const BasicBlock *BB,
} else {
BBPreds.insert(pred_begin(BB), pred_end(BB));
}
// Walk the preds of DestBB.
for (unsigned i = 0, e = DestBBPN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *Pred = DestBBPN->getIncomingBlock(i);
@ -177,12 +177,12 @@ bool CodeGenPrepare::CanMergeBlocks(const BasicBlock *BB,
while (const PHINode *PN = dyn_cast<PHINode>(BBI++)) {
const Value *V1 = PN->getIncomingValueForBlock(Pred);
const Value *V2 = PN->getIncomingValueForBlock(BB);
// If V2 is a phi node in BB, look up what the mapped value will be.
if (const PHINode *V2PN = dyn_cast<PHINode>(V2))
if (V2PN->getParent() == BB)
V2 = V2PN->getIncomingValueForBlock(Pred);
// If there is a conflict, bail out.
if (V1 != V2) return false;
}
@ -198,9 +198,9 @@ bool CodeGenPrepare::CanMergeBlocks(const BasicBlock *BB,
void CodeGenPrepare::EliminateMostlyEmptyBlock(BasicBlock *BB) {
BranchInst *BI = cast<BranchInst>(BB->getTerminator());
BasicBlock *DestBB = BI->getSuccessor(0);
DOUT << "MERGING MOSTLY EMPTY BLOCKS - BEFORE:\n" << *BB << *DestBB;
// If the destination block has a single pred, then this is a trivial edge,
// just collapse it.
if (DestBB->getSinglePredecessor()) {
@ -209,21 +209,21 @@ void CodeGenPrepare::EliminateMostlyEmptyBlock(BasicBlock *BB) {
PN->replaceAllUsesWith(PN->getIncomingValue(0));
PN->eraseFromParent();
}
// Splice all the PHI nodes from BB over to DestBB.
DestBB->getInstList().splice(DestBB->begin(), BB->getInstList(),
BB->begin(), BI);
// Anything that branched to BB now branches to DestBB.
BB->replaceAllUsesWith(DestBB);
// Nuke BB.
BB->eraseFromParent();
DOUT << "AFTER:\n" << *DestBB << "\n\n\n";
return;
}
// Otherwise, we have multiple predecessors of BB. Update the PHIs in DestBB
// to handle the new incoming edges it is about to have.
PHINode *PN;
@ -231,7 +231,7 @@ void CodeGenPrepare::EliminateMostlyEmptyBlock(BasicBlock *BB) {
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
// Remove the incoming value for BB, and remember it.
Value *InVal = PN->removeIncomingValue(BB, false);
// Two options: either the InVal is a phi node defined in BB or it is some
// value that dominates BB.
PHINode *InValPhi = dyn_cast<PHINode>(InVal);
@ -252,12 +252,12 @@ void CodeGenPrepare::EliminateMostlyEmptyBlock(BasicBlock *BB) {
}
}
}
// The PHIs are now updated, change everything that refers to BB to use
// DestBB and remove BB.
BB->replaceAllUsesWith(DestBB);
BB->eraseFromParent();
DOUT << "AFTER:\n" << *DestBB << "\n\n\n";
}
@ -272,17 +272,17 @@ static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
BasicBlock *Dest = TI->getSuccessor(SuccNum);
assert(isa<PHINode>(Dest->begin()) &&
"This should only be called if Dest has a PHI!");
// As a hack, never split backedges of loops. Even though the copy for any
// PHIs inserted on the backedge would be dead for exits from the loop, we
// assume that the cost of *splitting* the backedge would be too high.
if (Dest == TIBB)
return;
/// TIPHIValues - This array is lazily computed to determine the values of
/// PHIs in Dest that TI would provide.
SmallVector<Value*, 32> TIPHIValues;
// Check to see if Dest has any blocks that can be used as a split edge for
// this terminator.
for (pred_iterator PI = pred_begin(Dest), E = pred_end(Dest); PI != E; ++PI) {
@ -295,7 +295,7 @@ static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
// Cannot be the entry block; its label does not get emitted.
Pred == &(Dest->getParent()->getEntryBlock()))
continue;
// Finally, since we know that Dest has phi nodes in it, we have to make
// sure that jumping to Pred will have the same affect as going to Dest in
// terms of PHI values.
@ -306,14 +306,14 @@ static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
(PN = dyn_cast<PHINode>(I)); ++I, ++PHINo) {
if (PHINo == TIPHIValues.size())
TIPHIValues.push_back(PN->getIncomingValueForBlock(TIBB));
// If the PHI entry doesn't work, we can't use this pred.
if (TIPHIValues[PHINo] != PN->getIncomingValueForBlock(Pred)) {
FoundMatch = false;
break;
}
}
// If we found a workable predecessor, change TI to branch to Succ.
if (FoundMatch) {
Dest->removePredecessor(TIBB);
@ -321,8 +321,8 @@ static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
return;
}
}
SplitCriticalEdge(TI, SuccNum, P, true);
SplitCriticalEdge(TI, SuccNum, P, true);
}
/// OptimizeNoopCopyExpression - If the specified cast instruction is a noop
@ -332,10 +332,10 @@ static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
///
/// Return true if any changes are made.
static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI){
// If this is a noop copy,
// If this is a noop copy,
MVT SrcVT = TLI.getValueType(CI->getOperand(0)->getType());
MVT DstVT = TLI.getValueType(CI->getType());
// This is an fp<->int conversion?
if (SrcVT.isInteger() != DstVT.isInteger())
return false;
@ -343,7 +343,7 @@ static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI){
// If this is an extension, it will be a zero or sign extension, which
// isn't a noop.
if (SrcVT.bitsLT(DstVT)) return false;
// If these values will be promoted, find out what they will be promoted
// to. This helps us consider truncates on PPC as noop copies when they
// are.
@ -351,22 +351,22 @@ static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI){
SrcVT = TLI.getTypeToTransformTo(SrcVT);
if (TLI.getTypeAction(DstVT) == TargetLowering::Promote)
DstVT = TLI.getTypeToTransformTo(DstVT);
// If, after promotion, these are the same types, this is a noop copy.
if (SrcVT != DstVT)
return false;
BasicBlock *DefBB = CI->getParent();
/// InsertedCasts - Only insert a cast in each block once.
DenseMap<BasicBlock*, CastInst*> InsertedCasts;
bool MadeChange = false;
for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
UI != E; ) {
Use &TheUse = UI.getUse();
Instruction *User = cast<Instruction>(*UI);
// Figure out which BB this cast is used in. For PHI's this is the
// appropriate predecessor block.
BasicBlock *UserBB = User->getParent();
@ -374,39 +374,39 @@ static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI){
unsigned OpVal = UI.getOperandNo()/2;
UserBB = PN->getIncomingBlock(OpVal);
}
// Preincrement use iterator so we don't invalidate it.
++UI;
// If this user is in the same block as the cast, don't change the cast.
if (UserBB == DefBB) continue;
// If we have already inserted a cast into this block, use it.
CastInst *&InsertedCast = InsertedCasts[UserBB];
if (!InsertedCast) {
BasicBlock::iterator InsertPt = UserBB->getFirstNonPHI();
InsertedCast =
CastInst::Create(CI->getOpcode(), CI->getOperand(0), CI->getType(), "",
InsertedCast =
CastInst::Create(CI->getOpcode(), CI->getOperand(0), CI->getType(), "",
InsertPt);
MadeChange = true;
}
// Replace a use of the cast with a use of the new cast.
TheUse = InsertedCast;
}
// If we removed all uses, nuke the cast.
if (CI->use_empty()) {
CI->eraseFromParent();
MadeChange = true;
}
return MadeChange;
}
/// OptimizeCmpExpression - sink the given CmpInst into user blocks to reduce
/// OptimizeCmpExpression - sink the given CmpInst into user blocks to reduce
/// the number of virtual registers that must be created and coalesced. This is
/// a clear win except on targets with multiple condition code registers
/// (PowerPC), where it might lose; some adjustment may be wanted there.
@ -415,49 +415,49 @@ static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI){
static bool OptimizeCmpExpression(CmpInst *CI){
BasicBlock *DefBB = CI->getParent();
/// InsertedCmp - Only insert a cmp in each block once.
DenseMap<BasicBlock*, CmpInst*> InsertedCmps;
bool MadeChange = false;
for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
UI != E; ) {
Use &TheUse = UI.getUse();
Instruction *User = cast<Instruction>(*UI);
// Preincrement use iterator so we don't invalidate it.
++UI;
// Don't bother for PHI nodes.
if (isa<PHINode>(User))
continue;
// Figure out which BB this cmp is used in.
BasicBlock *UserBB = User->getParent();
// If this user is in the same block as the cmp, don't change the cmp.
if (UserBB == DefBB) continue;
// If we have already inserted a cmp into this block, use it.
CmpInst *&InsertedCmp = InsertedCmps[UserBB];
if (!InsertedCmp) {
BasicBlock::iterator InsertPt = UserBB->getFirstNonPHI();
InsertedCmp =
CmpInst::Create(CI->getOpcode(), CI->getPredicate(), CI->getOperand(0),
InsertedCmp =
CmpInst::Create(CI->getOpcode(), CI->getPredicate(), CI->getOperand(0),
CI->getOperand(1), "", InsertPt);
MadeChange = true;
}
// Replace a use of the cmp with a use of the new cmp.
TheUse = InsertedCmp;
}
// If we removed all uses, nuke the cmp.
if (CI->use_empty())
CI->eraseFromParent();
return MadeChange;
}
@ -465,10 +465,10 @@ static bool OptimizeCmpExpression(CmpInst *CI){
static void EraseDeadInstructions(Value *V) {
Instruction *I = dyn_cast<Instruction>(V);
if (!I || !I->use_empty()) return;
SmallPtrSet<Instruction*, 16> Insts;
Insts.insert(I);
while (!Insts.empty()) {
I = *Insts.begin();
Insts.erase(I);
@ -498,17 +498,17 @@ static std::ostream &operator<<(std::ostream &OS, const ExtAddrMode &AM) {
if (AM.BaseGV)
OS << (NeedPlus ? " + " : "")
<< "GV:%" << AM.BaseGV->getName(), NeedPlus = true;
if (AM.BaseOffs)
OS << (NeedPlus ? " + " : "") << AM.BaseOffs, NeedPlus = true;
if (AM.BaseReg)
OS << (NeedPlus ? " + " : "")
<< "Base:%" << AM.BaseReg->getName(), NeedPlus = true;
if (AM.Scale)
OS << (NeedPlus ? " + " : "")
<< AM.Scale << "*%" << AM.ScaledReg->getName(), NeedPlus = true;
return OS << "]";
}
@ -522,7 +522,7 @@ static bool TryMatchingScaledValue(Value *ScaleReg, int64_t Scale,
const Type *AccessTy, ExtAddrMode &AddrMode,
SmallVector<Instruction*, 16> &AddrModeInsts,
const TargetLowering &TLI, unsigned Depth);
/// FindMaximalLegalAddressingMode - If we can, try to merge the computation of
/// Addr into the specified addressing mode. If Addr can't be added to AddrMode
/// this returns false. This assumes that Addr is either a pointer type or
@ -532,7 +532,7 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
SmallVector<Instruction*, 16> &AddrModeInsts,
const TargetLowering &TLI,
unsigned Depth) {
// If this is a global variable, fold it into the addressing mode if possible.
if (GlobalValue *GV = dyn_cast<GlobalValue>(Addr)) {
if (AddrMode.BaseGV == 0) {
@ -549,7 +549,7 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
} else if (isa<ConstantPointerNull>(Addr)) {
return true;
}
// Look through constant exprs and instructions.
unsigned Opcode = ~0U;
User *AddrInst = 0;
@ -598,18 +598,18 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
// Restore the old addr mode info.
AddrMode = BackupAddrMode;
AddrModeInsts.resize(OldSize);
// Otherwise this was over-aggressive. Try merging in the LHS then the RHS.
if (FindMaximalLegalAddressingMode(AddrInst->getOperand(0), AccessTy,
AddrMode, AddrModeInsts, TLI, Depth+1) &&
FindMaximalLegalAddressingMode(AddrInst->getOperand(1), AccessTy,
AddrMode, AddrModeInsts, TLI, Depth+1))
return true;
// Otherwise we definitely can't merge the ADD in.
AddrMode = BackupAddrMode;
AddrModeInsts.resize(OldSize);
break;
break;
}
case Instruction::Or: {
ConstantInt *RHS = dyn_cast<ConstantInt>(AddrInst->getOperand(1));
@ -626,7 +626,7 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
int64_t Scale = RHS->getSExtValue();
if (Opcode == Instruction::Shl)
Scale = 1 << Scale;
if (TryMatchingScaledValue(AddrInst->getOperand(0), Scale, AccessTy,
AddrMode, AddrModeInsts, TLI, Depth))
return true;
@ -637,7 +637,7 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
// one variable offset.
int VariableOperand = -1;
unsigned VariableScale = 0;
int64_t ConstantOffset = 0;
const TargetData *TD = TLI.getTargetData();
gep_type_iterator GTI = gep_type_begin(AddrInst);
@ -657,7 +657,7 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
VariableOperand = -2;
break;
}
// Remember the variable index.
VariableOperand = i;
VariableScale = TypeSize;
@ -693,11 +693,11 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
AddrMode.BaseReg = AddrInst->getOperand(0);
SetBaseReg = true;
}
// See if the scale amount is valid for this target.
AddrMode.BaseOffs += ConstantOffset;
if (TryMatchingScaledValue(AddrInst->getOperand(VariableOperand),
VariableScale, AccessTy, AddrMode,
VariableScale, AccessTy, AddrMode,
AddrModeInsts, TLI, Depth)) {
if (!SetBaseReg) return true;
@ -710,27 +710,27 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
Depth+1))
return true;
// Strange, shouldn't happen. Restore the base reg and succeed the easy
// way.
// way.
AddrMode.HasBaseReg = true;
AddrMode.BaseReg = AddrInst->getOperand(0);
return true;
}
AddrMode.BaseOffs -= ConstantOffset;
if (SetBaseReg) {
AddrMode.HasBaseReg = false;
AddrMode.BaseReg = 0;
}
}
break;
break;
}
}
if (Instruction *I = dyn_cast_or_null<Instruction>(AddrInst)) {
assert(AddrModeInsts.back() == I && "Stack imbalance"); I = I;
AddrModeInsts.pop_back();
}
// Worse case, the target should support [reg] addressing modes. :)
if (!AddrMode.HasBaseReg) {
AddrMode.HasBaseReg = true;
@ -741,7 +741,7 @@ static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
}
AddrMode.HasBaseReg = false;
}
// If the base register is already taken, see if we can do [r+r].
if (AddrMode.Scale == 0) {
AddrMode.Scale = 1;
@ -766,14 +766,14 @@ static bool TryMatchingScaledValue(Value *ScaleReg, int64_t Scale,
// need an available scale field.
if (AddrMode.Scale != 0 && AddrMode.ScaledReg != ScaleReg)
return false;
ExtAddrMode InputAddrMode = AddrMode;
// Add scale to turn X*4+X*3 -> X*7. This could also do things like
// [A+B + A*7] -> [B+A*8].
AddrMode.Scale += Scale;
AddrMode.ScaledReg = ScaleReg;
if (TLI.isLegalAddressingMode(AddrMode, AccessTy)) {
// Okay, we decided that we can add ScaleReg+Scale to AddrMode. Check now
// to see if ScaleReg is actually X+C. If so, we can turn this into adding
@ -781,10 +781,10 @@ static bool TryMatchingScaledValue(Value *ScaleReg, int64_t Scale,
BinaryOperator *BinOp = dyn_cast<BinaryOperator>(ScaleReg);
if (BinOp && BinOp->getOpcode() == Instruction::Add &&
isa<ConstantInt>(BinOp->getOperand(1)) && InputAddrMode.ScaledReg ==0) {
InputAddrMode.Scale = Scale;
InputAddrMode.ScaledReg = BinOp->getOperand(0);
InputAddrMode.BaseOffs +=
InputAddrMode.BaseOffs +=
cast<ConstantInt>(BinOp->getOperand(1))->getSExtValue()*Scale;
if (TLI.isLegalAddressingMode(InputAddrMode, AccessTy)) {
AddrModeInsts.push_back(BinOp);
@ -796,11 +796,11 @@ static bool TryMatchingScaledValue(Value *ScaleReg, int64_t Scale,
// Otherwise, not (x+c)*scale, just return what we have.
return true;
}
// Otherwise, back this attempt out.
AddrMode.Scale -= Scale;
if (AddrMode.Scale == 0) AddrMode.ScaledReg = 0;
return false;
}
@ -828,7 +828,7 @@ bool CodeGenPrepare::OptimizeLoadStoreInst(Instruction *LdStInst, Value *Addr,
bool Success = FindMaximalLegalAddressingMode(Addr, AccessTy, AddrMode,
AddrModeInsts, *TLI, 0);
Success = Success; assert(Success && "Couldn't select *anything*?");
// Check to see if any of the instructions supersumed by this addr mode are
// non-local to I's BB.
bool AnyNonLocal = false;
@ -838,18 +838,18 @@ bool CodeGenPrepare::OptimizeLoadStoreInst(Instruction *LdStInst, Value *Addr,
break;
}
}
// If all the instructions matched are already in this BB, don't do anything.
if (!AnyNonLocal) {
DEBUG(cerr << "CGP: Found local addrmode: " << AddrMode << "\n");
return false;
}
// Insert this computation right after this user. Since our caller is
// scanning from the top of the BB to the bottom, reuse of the expr are
// guaranteed to happen later.
BasicBlock::iterator InsertPt = LdStInst;
// Now that we determined the addressing expression we want to use and know
// that we have to sink it into this block. Check to see if we have already
// done this for some other load/store instr in this block. If so, reuse the
@ -862,7 +862,7 @@ bool CodeGenPrepare::OptimizeLoadStoreInst(Instruction *LdStInst, Value *Addr,
} else {
DEBUG(cerr << "CGP: SINKING nonlocal addrmode: " << AddrMode << "\n");
const Type *IntPtrTy = TLI->getTargetData()->getIntPtrType();
Value *Result = 0;
// Start with the scale value.
if (AddrMode.Scale) {
@ -894,7 +894,7 @@ bool CodeGenPrepare::OptimizeLoadStoreInst(Instruction *LdStInst, Value *Addr,
else
Result = V;
}
// Add in the BaseGV if present.
if (AddrMode.BaseGV) {
Value *V = new PtrToIntInst(AddrMode.BaseGV, IntPtrTy, "sunkaddr",
@ -904,7 +904,7 @@ bool CodeGenPrepare::OptimizeLoadStoreInst(Instruction *LdStInst, Value *Addr,
else
Result = V;
}
// Add in the Base Offset if present.
if (AddrMode.BaseOffs) {
Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs);
@ -919,14 +919,31 @@ bool CodeGenPrepare::OptimizeLoadStoreInst(Instruction *LdStInst, Value *Addr,
else
SunkAddr = new IntToPtrInst(Result, Addr->getType(), "sunkaddr",InsertPt);
}
LdStInst->replaceUsesOfWith(Addr, SunkAddr);
if (Addr->use_empty())
EraseDeadInstructions(Addr);
return true;
}
/// hasInlineAsmMemConstraint - Return true if the inline asm instruction being
/// processed uses a memory 'm' constraint.
static bool
hasInlineAsmMemConstraint(std::vector<InlineAsm::ConstraintInfo> &CInfos,
const TargetLowering *TLI) {
for (unsigned i = 0, e = CInfos.size(); i != e; ++i) {
InlineAsm::ConstraintInfo &CI = CInfos[i];
for (unsigned j = 0, ee = CI.Codes.size(); j != ee; ++j) {
TargetLowering::ConstraintType CType = TLI->getConstraintType(CI.Codes[j]);
if (CType == TargetLowering::C_Memory)
return true;
}
}
return false;
}
/// OptimizeInlineAsmInst - If there are any memory operands, use
/// OptimizeLoadStoreInt to sink their address computing into the block when
/// possible / profitable.
@ -963,7 +980,8 @@ bool CodeGenPrepare::OptimizeInlineAsmInst(Instruction *I, CallSite CS,
}
// Compute the constraint code and ConstraintType to use.
TLI->ComputeConstraintToUse(OpInfo, SDValue());
bool hasMemory = hasInlineAsmMemConstraint(ConstraintInfos, TLI);
TLI->ComputeConstraintToUse(OpInfo, SDValue(), hasMemory);
if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
OpInfo.isIndirect) {
@ -995,7 +1013,7 @@ bool CodeGenPrepare::OptimizeExtUses(Instruction *I) {
return false;
bool DefIsLiveOut = false;
for (Value::use_iterator UI = I->use_begin(), E = I->use_end();
for (Value::use_iterator UI = I->use_begin(), E = I->use_end();
UI != E; ++UI) {
Instruction *User = cast<Instruction>(*UI);
@ -1009,7 +1027,7 @@ bool CodeGenPrepare::OptimizeExtUses(Instruction *I) {
return false;
// Make sure non of the uses are PHI nodes.
for (Value::use_iterator UI = Src->use_begin(), E = Src->use_end();
for (Value::use_iterator UI = Src->use_begin(), E = Src->use_end();
UI != E; ++UI) {
Instruction *User = cast<Instruction>(*UI);
BasicBlock *UserBB = User->getParent();
@ -1024,7 +1042,7 @@ bool CodeGenPrepare::OptimizeExtUses(Instruction *I) {
DenseMap<BasicBlock*, Instruction*> InsertedTruncs;
bool MadeChange = false;
for (Value::use_iterator UI = Src->use_begin(), E = Src->use_end();
for (Value::use_iterator UI = Src->use_begin(), E = Src->use_end();
UI != E; ++UI) {
Use &TheUse = UI.getUse();
Instruction *User = cast<Instruction>(*UI);
@ -1038,7 +1056,7 @@ bool CodeGenPrepare::OptimizeExtUses(Instruction *I) {
if (!InsertedTrunc) {
BasicBlock::iterator InsertPt = UserBB->getFirstNonPHI();
InsertedTrunc = new TruncInst(I, Src->getType(), "", InsertPt);
}
@ -1056,7 +1074,7 @@ bool CodeGenPrepare::OptimizeExtUses(Instruction *I) {
// selection.
bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
bool MadeChange = false;
// Split all critical edges where the dest block has a PHI and where the phi
// has shared immediate operands.
TerminatorInst *BBTI = BB.getTerminator();
@ -1066,16 +1084,16 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
isCriticalEdge(BBTI, i, true))
SplitEdgeNicely(BBTI, i, this);
}
// Keep track of non-local addresses that have been sunk into this block.
// This allows us to avoid inserting duplicate code for blocks with multiple
// load/stores of the same address.
DenseMap<Value*, Value*> SunkAddrs;
for (BasicBlock::iterator BBI = BB.begin(), E = BB.end(); BBI != E; ) {
Instruction *I = BBI++;
if (CastInst *CI = dyn_cast<CastInst>(I)) {
// If the source of the cast is a constant, then this should have
// already been constant folded. The only reason NOT to constant fold
@ -1085,7 +1103,7 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
// want to forward-subst the cast.
if (isa<Constant>(CI->getOperand(0)))
continue;
bool Change = false;
if (TLI) {
Change = OptimizeNoopCopyExpression(CI, *TLI);
@ -1108,7 +1126,7 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
} else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(I)) {
if (GEPI->hasAllZeroIndices()) {
/// The GEP operand must be a pointer, so must its result -> BitCast
Instruction *NC = new BitCastInst(GEPI->getOperand(0), GEPI->getType(),
Instruction *NC = new BitCastInst(GEPI->getOperand(0), GEPI->getType(),
GEPI->getName(), GEPI);
GEPI->replaceAllUsesWith(NC);
GEPI->eraseFromParent();
@ -1119,7 +1137,7 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
// If we found an inline asm expession, and if the target knows how to
// lower it to normal LLVM code, do so now.
if (TLI && isa<InlineAsm>(CI->getCalledValue()))
if (const TargetAsmInfo *TAI =
if (const TargetAsmInfo *TAI =
TLI->getTargetMachine().getTargetAsmInfo()) {
if (TAI->ExpandInlineAsm(CI))
BBI = BB.begin();
@ -1129,7 +1147,6 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
}
}
}
return MadeChange;
}