[llvm-commits] [llvm] r86855 - /llvm/trunk/lib/CodeGen/BranchFolding.cpp
Dan Gohman
gohman at apple.com
Wed Nov 11 10:38:14 PST 2009
Author: djg
Date: Wed Nov 11 12:38:14 2009
New Revision: 86855
URL: http://llvm.org/viewvc/llvm-project?rev=86855&view=rev
Log:
Whitespace cleanups.
Modified:
llvm/trunk/lib/CodeGen/BranchFolding.cpp
Modified: llvm/trunk/lib/CodeGen/BranchFolding.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/BranchFolding.cpp?rev=86855&r1=86854&r2=86855&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/BranchFolding.cpp (original)
+++ llvm/trunk/lib/CodeGen/BranchFolding.cpp Wed Nov 11 12:38:14 2009
@@ -40,18 +40,18 @@
STATISTIC(NumDeadBlocks, "Number of dead blocks removed");
STATISTIC(NumBranchOpts, "Number of branches optimized");
STATISTIC(NumTailMerge , "Number of block tails merged");
-static cl::opt<cl::boolOrDefault> FlagEnableTailMerge("enable-tail-merge",
+static cl::opt<cl::boolOrDefault> FlagEnableTailMerge("enable-tail-merge",
cl::init(cl::BOU_UNSET), cl::Hidden);
// Throttle for huge numbers of predecessors (compile speed problems)
static cl::opt<unsigned>
-TailMergeThreshold("tail-merge-threshold",
+TailMergeThreshold("tail-merge-threshold",
cl::desc("Max number of predecessors to consider tail merging"),
cl::init(150), cl::Hidden);
char BranchFolderPass::ID = 0;
-FunctionPass *llvm::createBranchFoldingPass(bool DefaultEnableTailMerge) {
+FunctionPass *llvm::createBranchFoldingPass(bool DefaultEnableTailMerge) {
return new BranchFolderPass(DefaultEnableTailMerge);
}
@@ -63,7 +63,6 @@
}
-
BranchFolder::BranchFolder(bool defaultEnableTailMerge) {
switch (FlagEnableTailMerge) {
case cl::BOU_UNSET: EnableTailMerge = defaultEnableTailMerge; break;
@@ -77,12 +76,12 @@
void BranchFolder::RemoveDeadBlock(MachineBasicBlock *MBB) {
assert(MBB->pred_empty() && "MBB must be dead!");
DEBUG(errs() << "\nRemoving MBB: " << *MBB);
-
+
MachineFunction *MF = MBB->getParent();
// drop all successors.
while (!MBB->succ_empty())
MBB->removeSuccessor(MBB->succ_end()-1);
-
+
// If there are any labels in the basic block, unregister them from
// MachineModuleInfo.
if (MMI && !MBB->empty()) {
@@ -93,7 +92,7 @@
MMI->InvalidateLabel(I->getOperand(0).getImm());
}
}
-
+
// Remove the block.
MF->erase(MBB);
}
@@ -190,7 +189,7 @@
// Figure out how these jump tables should be merged.
std::vector<unsigned> JTMapping;
JTMapping.reserve(JTs.size());
-
+
// We always keep the 0th jump table.
JTMapping.push_back(0);
@@ -202,7 +201,7 @@
else
JTMapping.push_back(JTI->getJumpTableIndex(JTs[i].MBBs));
}
-
+
// If a jump table was merge with another one, walk the function rewriting
// references to jump tables to reference the new JT ID's. Keep track of
// whether we see a jump table idx, if not, we can delete the JT.
@@ -221,7 +220,7 @@
JTIsLive.set(NewIdx);
}
}
-
+
// Finally, remove dead jump tables. This happens either because the
// indirect jump was unreachable (and thus deleted) or because the jump
// table was merged with some other one.
@@ -245,7 +244,7 @@
unsigned Hash = MI->getOpcode();
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &Op = MI->getOperand(i);
-
+
// Merge in bits from the operand if easy.
unsigned OperandHash = 0;
switch (Op.getType()) {
@@ -267,31 +266,30 @@
break;
default: break;
}
-
+
Hash += ((OperandHash << 3) | Op.getType()) << (i&31);
}
return Hash;
}
/// HashEndOfMBB - Hash the last few instructions in the MBB. For blocks
-/// with no successors, we hash two instructions, because cross-jumping
-/// only saves code when at least two instructions are removed (since a
+/// with no successors, we hash two instructions, because cross-jumping
+/// only saves code when at least two instructions are removed (since a
/// branch must be inserted). For blocks with a successor, one of the
/// two blocks to be tail-merged will end with a branch already, so
/// it gains to cross-jump even for one instruction.
-
static unsigned HashEndOfMBB(const MachineBasicBlock *MBB,
unsigned minCommonTailLength) {
MachineBasicBlock::const_iterator I = MBB->end();
if (I == MBB->begin())
return 0; // Empty MBB.
-
+
--I;
unsigned Hash = HashMachineInstr(I);
-
+
if (I == MBB->begin() || minCommonTailLength == 1)
return Hash; // Single instr MBB.
-
+
--I;
// Hash in the second-to-last instruction.
Hash ^= HashMachineInstr(I) << 2;
@@ -307,11 +305,11 @@
MachineBasicBlock::iterator &I2) {
I1 = MBB1->end();
I2 = MBB2->end();
-
+
unsigned TailLen = 0;
while (I1 != MBB1->begin() && I2 != MBB2->begin()) {
--I1; --I2;
- if (!I1->isIdenticalTo(I2) ||
+ if (!I1->isIdenticalTo(I2) ||
// FIXME: This check is dubious. It's used to get around a problem where
// people incorrectly expect inline asm directives to remain in the same
// relative order. This is untenable because normal compiler
@@ -332,11 +330,11 @@
void BranchFolder::ReplaceTailWithBranchTo(MachineBasicBlock::iterator OldInst,
MachineBasicBlock *NewDest) {
MachineBasicBlock *OldBB = OldInst->getParent();
-
+
// Remove all the old successors of OldBB from the CFG.
while (!OldBB->succ_empty())
OldBB->removeSuccessor(OldBB->succ_begin());
-
+
// Remove all the dead instructions from the end of OldBB.
OldBB->erase(OldInst, OldBB->end());
@@ -361,10 +359,10 @@
// Move all the successors of this block to the specified block.
NewMBB->transferSuccessors(&CurMBB);
-
+
// Add an edge from CurMBB to NewMBB for the fall-through.
CurMBB.addSuccessor(NewMBB);
-
+
// Splice the code over.
NewMBB->splice(NewMBB->end(), &CurMBB, BBI1, CurMBB.end());
@@ -404,7 +402,6 @@
// branches temporarily for tail merging). In the case where CurMBB ends
// with a conditional branch to the next block, optimize by reversing the
// test and conditionally branching to SuccMBB instead.
-
static void FixTail(MachineBasicBlock* CurMBB, MachineBasicBlock *SuccBB,
const TargetInstrInfo *TII) {
MachineFunction *MF = CurMBB->getParent();
@@ -476,26 +473,26 @@
}
/// ComputeSameTails - Look through all the blocks in MergePotentials that have
-/// hash CurHash (guaranteed to match the last element). Build the vector
+/// hash CurHash (guaranteed to match the last element). Build the vector
/// SameTails of all those that have the (same) largest number of instructions
/// in common of any pair of these blocks. SameTails entries contain an
-/// iterator into MergePotentials (from which the MachineBasicBlock can be
-/// found) and a MachineBasicBlock::iterator into that MBB indicating the
+/// iterator into MergePotentials (from which the MachineBasicBlock can be
+/// found) and a MachineBasicBlock::iterator into that MBB indicating the
/// instruction where the matching code sequence begins.
/// Order of elements in SameTails is the reverse of the order in which
/// those blocks appear in MergePotentials (where they are not necessarily
/// consecutive).
-unsigned BranchFolder::ComputeSameTails(unsigned CurHash,
+unsigned BranchFolder::ComputeSameTails(unsigned CurHash,
unsigned minCommonTailLength) {
unsigned maxCommonTailLength = 0U;
SameTails.clear();
MachineBasicBlock::iterator TrialBBI1, TrialBBI2;
MPIterator HighestMPIter = prior(MergePotentials.end());
for (MPIterator CurMPIter = prior(MergePotentials.end()),
- B = MergePotentials.begin();
- CurMPIter!=B && CurMPIter->first==CurHash;
+ B = MergePotentials.begin();
+ CurMPIter!=B && CurMPIter->first == CurHash;
--CurMPIter) {
- for (MPIterator I = prior(CurMPIter); I->first==CurHash ; --I) {
+ for (MPIterator I = prior(CurMPIter); I->first == CurHash ; --I) {
unsigned CommonTailLen;
if (ProfitableToMerge(CurMPIter->second, I->second, minCommonTailLength,
CommonTailLen, TrialBBI1, TrialBBI2)) {
@@ -509,7 +506,7 @@
CommonTailLen == maxCommonTailLength)
SameTails.push_back(std::make_pair(I, TrialBBI2));
}
- if (I==B)
+ if (I == B)
break;
}
}
@@ -518,18 +515,18 @@
/// RemoveBlocksWithHash - Remove all blocks with hash CurHash from
/// MergePotentials, restoring branches at ends of blocks as appropriate.
-void BranchFolder::RemoveBlocksWithHash(unsigned CurHash,
+void BranchFolder::RemoveBlocksWithHash(unsigned CurHash,
MachineBasicBlock* SuccBB,
MachineBasicBlock* PredBB) {
MPIterator CurMPIter, B;
- for (CurMPIter = prior(MergePotentials.end()), B = MergePotentials.begin();
- CurMPIter->first==CurHash;
+ for (CurMPIter = prior(MergePotentials.end()), B = MergePotentials.begin();
+ CurMPIter->first == CurHash;
--CurMPIter) {
// Put the unconditional branch back, if we need one.
MachineBasicBlock *CurMBB = CurMPIter->second;
if (SuccBB && CurMBB != PredBB)
FixTail(CurMBB, SuccBB, TII);
- if (CurMPIter==B)
+ if (CurMPIter == B)
break;
}
if (CurMPIter->first!=CurHash)
@@ -545,15 +542,15 @@
unsigned TimeEstimate = ~0U;
for (i=0, commonTailIndex=0; i<SameTails.size(); i++) {
// Use PredBB if possible; that doesn't require a new branch.
- if (SameTails[i].first->second==PredBB) {
+ if (SameTails[i].first->second == PredBB) {
commonTailIndex = i;
break;
}
// Otherwise, make a (fairly bogus) choice based on estimate of
// how long it will take the various blocks to execute.
- unsigned t = EstimateRuntime(SameTails[i].first->second->begin(),
+ unsigned t = EstimateRuntime(SameTails[i].first->second->begin(),
SameTails[i].second);
- if (t<=TimeEstimate) {
+ if (t <= TimeEstimate) {
TimeEstimate = t;
commonTailIndex = i;
}
@@ -568,8 +565,9 @@
MachineBasicBlock *newMBB = SplitMBBAt(*MBB, BBI);
SameTails[commonTailIndex].first->second = newMBB;
SameTails[commonTailIndex].second = newMBB->begin();
+
// If we split PredBB, newMBB is the new predecessor.
- if (PredBB==MBB)
+ if (PredBB == MBB)
PredBB = newMBB;
return commonTailIndex;
@@ -579,7 +577,7 @@
// successor, or all have no successor) can be tail-merged. If there is a
// successor, any blocks in MergePotentials that are not tail-merged and
// are not immediately before Succ must have an unconditional branch to
-// Succ added (but the predecessor/successor lists need no adjustment).
+// Succ added (but the predecessor/successor lists need no adjustment).
// The lone predecessor of Succ that falls through into Succ,
// if any, is given in PredBB.
@@ -591,7 +589,7 @@
// will add a jump.
// FIXME: Ask the target to provide the threshold?
unsigned minCommonTailLength = (SuccBB ? 1 : 2) + 1;
-
+
DEBUG(errs() << "\nTryMergeBlocks " << MergePotentials.size() << '\n');
// Sort by hash value so that blocks with identical end sequences sort
@@ -601,13 +599,13 @@
// Walk through equivalence sets looking for actual exact matches.
while (MergePotentials.size() > 1) {
unsigned CurHash = MergePotentials.back().first;
-
+
// Build SameTails, identifying the set of blocks with this hash code
// and with the maximum number of instructions in common.
- unsigned maxCommonTailLength = ComputeSameTails(CurHash,
+ unsigned maxCommonTailLength = ComputeSameTails(CurHash,
minCommonTailLength);
- // If we didn't find any pair that has at least minCommonTailLength
+ // If we didn't find any pair that has at least minCommonTailLength
// instructions in common, remove all blocks with this hash code and retry.
if (SameTails.empty()) {
RemoveBlocksWithHash(CurHash, SuccBB, PredBB);
@@ -625,12 +623,12 @@
MachineBasicBlock *MBB = SameTails[i].first->second;
if (MBB->begin() == SameTails[i].second && MBB != EntryBB) {
commonTailIndex = i;
- if (MBB==PredBB)
+ if (MBB == PredBB)
break;
}
}
- if (commonTailIndex==SameTails.size()) {
+ if (commonTailIndex == SameTails.size()) {
// None of the blocks consist entirely of the common tail.
// Split a block so that one does.
commonTailIndex = CreateCommonTailOnlyBlock(PredBB, maxCommonTailLength);
@@ -641,7 +639,7 @@
// Traversal must be forwards so erases work.
DEBUG(errs() << "\nUsing common tail BB#" << MBB->getNumber() << " for ");
for (unsigned int i=0; i<SameTails.size(); ++i) {
- if (commonTailIndex==i)
+ if (commonTailIndex == i)
continue;
DEBUG(errs() << "BB#" << SameTails[i].first->second->getNumber() << ", ");
// Hack the end off BB i, making it jump to BB commonTailIndex instead.
@@ -660,7 +658,7 @@
bool BranchFolder::TailMergeBlocks(MachineFunction &MF) {
if (!EnableTailMerge) return false;
-
+
bool MadeChange = false;
// First find blocks with no successors.
@@ -669,6 +667,7 @@
if (I->succ_empty())
MergePotentials.push_back(std::make_pair(HashEndOfMBB(I, 2U), I));
}
+
// See if we can do any tail merging on those.
if (MergePotentials.size() < TailMergeThreshold &&
MergePotentials.size() >= 2)
@@ -679,7 +678,7 @@
// (1) temporarily removing any unconditional branch from the predecessor
// to IBB, and
// (2) alter conditional branches so they branch to the other block
- // not IBB; this may require adding back an unconditional branch to IBB
+ // not IBB; this may require adding back an unconditional branch to IBB
// later, where there wasn't one coming in. E.g.
// Bcc IBB
// fallthrough to QBB
@@ -699,12 +698,12 @@
MachineBasicBlock *IBB = I;
MachineBasicBlock *PredBB = prior(I);
MergePotentials.clear();
- for (MachineBasicBlock::pred_iterator P = I->pred_begin(),
+ for (MachineBasicBlock::pred_iterator P = I->pred_begin(),
E2 = I->pred_end();
P != E2; ++P) {
MachineBasicBlock* PBB = *P;
// Skip blocks that loop to themselves, can't tail merge these.
- if (PBB==IBB)
+ if (PBB == IBB)
continue;
// Visit each predecessor only once.
if (!UniquePreds.insert(PBB))
@@ -715,7 +714,7 @@
// Failing case: IBB is the target of a cbr, and
// we cannot reverse the branch.
SmallVector<MachineOperand, 4> NewCond(Cond);
- if (!Cond.empty() && TBB==IBB) {
+ if (!Cond.empty() && TBB == IBB) {
if (TII->ReverseBranchCondition(NewCond))
continue;
// This is the QBB case described above
@@ -730,7 +729,7 @@
MachineBasicBlock* PredNextBB = NULL;
if (IP!=MF.end())
PredNextBB = IP;
- if (TBB==NULL) {
+ if (TBB == NULL) {
if (IBB!=PredNextBB) // fallthrough
continue;
} else if (FBB) {
@@ -749,7 +748,7 @@
TII->RemoveBranch(*PBB);
if (!Cond.empty())
// reinsert conditional branch only, for now
- TII->InsertBranch(*PBB, (TBB==IBB) ? FBB : TBB, 0, NewCond);
+ TII->InsertBranch(*PBB, (TBB == IBB) ? FBB : TBB, 0, NewCond);
}
MergePotentials.push_back(std::make_pair(HashEndOfMBB(PBB, 1U), *P));
}
@@ -759,7 +758,7 @@
// Reinsert an unconditional branch if needed.
// The 1 below can occur as a result of removing blocks in TryMergeBlocks.
PredBB = prior(I); // this may have been changed in TryMergeBlocks
- if (MergePotentials.size()==1 &&
+ if (MergePotentials.size() == 1 &&
MergePotentials.begin()->second != PredBB)
FixTail(MergePotentials.begin()->second, I, TII);
}
@@ -773,14 +772,14 @@
bool BranchFolder::OptimizeBranches(MachineFunction &MF) {
bool MadeChange = false;
-
+
// Make sure blocks are numbered in order
MF.RenumberBlocks();
for (MachineFunction::iterator I = ++MF.begin(), E = MF.end(); I != E; ) {
MachineBasicBlock *MBB = I++;
MadeChange |= OptimizeBlock(MBB);
-
+
// If it is dead, remove it.
if (MBB->pred_empty()) {
RemoveDeadBlock(MBB);
@@ -801,7 +800,7 @@
///
bool BranchFolder::CanFallThrough(MachineBasicBlock *CurBB,
bool BranchUnAnalyzable,
- MachineBasicBlock *TBB,
+ MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond) {
MachineFunction::iterator Fallthrough = CurBB;
@@ -809,14 +808,14 @@
// If FallthroughBlock is off the end of the function, it can't fall through.
if (Fallthrough == CurBB->getParent()->end())
return false;
-
+
// If FallthroughBlock isn't a successor of CurBB, no fallthrough is possible.
if (!CurBB->isSuccessor(Fallthrough))
return false;
-
+
// If we couldn't analyze the branch, assume it could fall through.
if (BranchUnAnalyzable) return true;
-
+
// If there is no branch, control always falls through.
if (TBB == 0) return true;
@@ -825,11 +824,11 @@
if (MachineFunction::iterator(TBB) == Fallthrough ||
MachineFunction::iterator(FBB) == Fallthrough)
return true;
-
- // If it's an unconditional branch to some block not the fall through, it
+
+ // If it's an unconditional branch to some block not the fall through, it
// doesn't fall through.
if (Cond.empty()) return false;
-
+
// Otherwise, if it is conditional and has no explicit false block, it falls
// through.
return FBB == 0;
@@ -853,14 +852,14 @@
/// fall-through to MBB1 than to fall through into MBB2. This has to return
/// a strict ordering, returning true for both (MBB1,MBB2) and (MBB2,MBB1) will
/// result in infinite loops.
-static bool IsBetterFallthrough(MachineBasicBlock *MBB1,
+static bool IsBetterFallthrough(MachineBasicBlock *MBB1,
MachineBasicBlock *MBB2) {
// Right now, we use a simple heuristic. If MBB2 ends with a call, and
// MBB1 doesn't, we prefer to fall through into MBB1. This allows us to
// optimize branches that branch to either a return block or an assert block
// into a fallthrough to the return.
if (MBB1->empty() || MBB2->empty()) return false;
-
+
// If there is a clear successor ordering we make sure that one block
// will fall through to the next
if (MBB1->isSuccessor(MBB2)) return true;
@@ -879,7 +878,7 @@
MachineFunction::iterator FallThrough = MBB;
++FallThrough;
-
+
// If this block is empty, make everyone use its fall-through, not the block
// explicitly. Landing pads should not do this since the landing-pad table
// points to this block. Blocks with their addresses taken shouldn't be
@@ -887,7 +886,7 @@
if (MBB->empty() && !MBB->isLandingPad() && !MBB->hasAddressTaken()) {
// Dead block? Leave for cleanup later.
if (MBB->pred_empty()) return MadeChange;
-
+
if (FallThrough == MF.end()) {
// TODO: Simplify preds to not branch here if possible!
} else {
@@ -917,20 +916,20 @@
// If the CFG for the prior block has extra edges, remove them.
MadeChange |= PrevBB.CorrectExtraCFGEdges(PriorTBB, PriorFBB,
!PriorCond.empty());
-
+
// If the previous branch is conditional and both conditions go to the same
// destination, remove the branch, replacing it with an unconditional one or
// a fall-through.
if (PriorTBB && PriorTBB == PriorFBB) {
TII->RemoveBranch(PrevBB);
- PriorCond.clear();
+ PriorCond.clear();
if (PriorTBB != MBB)
TII->InsertBranch(PrevBB, PriorTBB, 0, PriorCond);
MadeChange = true;
++NumBranchOpts;
return OptimizeBlock(MBB);
}
-
+
// If the previous branch *only* branches to *this* block (conditional or
// not) remove the branch.
if (PriorTBB == MBB && PriorFBB == 0) {
@@ -939,7 +938,7 @@
++NumBranchOpts;
return OptimizeBlock(MBB);
}
-
+
// If the prior block branches somewhere else on the condition and here if
// the condition is false, remove the uncond second branch.
if (PriorFBB == MBB) {
@@ -949,7 +948,7 @@
++NumBranchOpts;
return OptimizeBlock(MBB);
}
-
+
// If the prior block branches here on true and somewhere else on false, and
// if the branch condition is reversible, reverse the branch to create a
// fall-through.
@@ -963,7 +962,7 @@
return OptimizeBlock(MBB);
}
}
-
+
// If this block has no successors (e.g. it is a return block or ends with
// a call to a no-return function like abort or __cxa_throw) and if the pred
// falls through into this block, and if it would otherwise fall through
@@ -976,7 +975,7 @@
MachineFunction::iterator(PriorTBB) == FallThrough &&
!CanFallThrough(MBB)) {
bool DoTransform = true;
-
+
// We have to be careful that the succs of PredBB aren't both no-successor
// blocks. If neither have successors and if PredBB is the second from
// last block in the function, we'd just keep swapping the two blocks for
@@ -1000,15 +999,15 @@
if (DoTransform && !MBB->succ_empty() &&
(!CanFallThrough(PriorTBB) || PriorTBB->empty()))
DoTransform = false;
-
-
+
+
if (DoTransform) {
// Reverse the branch so we will fall through on the previous true cond.
SmallVector<MachineOperand, 4> NewPriorCond(PriorCond);
if (!TII->ReverseBranchCondition(NewPriorCond)) {
DEBUG(errs() << "\nMoving MBB: " << *MBB
<< "To make fallthrough to: " << *PriorTBB << "\n");
-
+
TII->RemoveBranch(PrevBB);
TII->InsertBranch(PrevBB, MBB, 0, NewPriorCond);
@@ -1021,7 +1020,7 @@
}
}
}
-
+
// Analyze the branch in the current block.
MachineBasicBlock *CurTBB = 0, *CurFBB = 0;
SmallVector<MachineOperand, 4> CurCond;
@@ -1030,7 +1029,7 @@
// If the CFG for the prior block has extra edges, remove them.
MadeChange |= MBB->CorrectExtraCFGEdges(CurTBB, CurFBB, !CurCond.empty());
- // If this is a two-way branch, and the FBB branches to this block, reverse
+ // If this is a two-way branch, and the FBB branches to this block, reverse
// the condition so the single-basic-block loop is faster. Instead of:
// Loop: xxx; jcc Out; jmp Loop
// we want:
@@ -1045,11 +1044,11 @@
return OptimizeBlock(MBB);
}
}
-
-
+
+
// If this branch is the only thing in its block, see if we can forward
// other blocks across it.
- if (CurTBB && CurCond.empty() && CurFBB == 0 &&
+ if (CurTBB && CurCond.empty() && CurFBB == 0 &&
MBB->begin()->getDesc().isBranch() && CurTBB != MBB &&
!MBB->hasAddressTaken()) {
// This block may contain just an unconditional branch. Because there can
@@ -1068,7 +1067,7 @@
!PrevBB.isSuccessor(MBB)) {
// If the prior block falls through into us, turn it into an
// explicit branch to us to make updates simpler.
- if (!PredHasNoFallThrough && PrevBB.isSuccessor(MBB) &&
+ if (!PredHasNoFallThrough && PrevBB.isSuccessor(MBB) &&
PriorTBB != MBB && PriorFBB != MBB) {
if (PriorTBB == 0) {
assert(PriorCond.empty() && PriorFBB == 0 &&
@@ -1104,7 +1103,7 @@
NewCurFBB, NewCurCond, true);
if (!NewCurUnAnalyzable && NewCurTBB && NewCurTBB == NewCurFBB) {
TII->RemoveBranch(*PMBB);
- NewCurCond.clear();
+ NewCurCond.clear();
TII->InsertBranch(*PMBB, NewCurTBB, 0, NewCurCond);
MadeChange = true;
++NumBranchOpts;
@@ -1122,7 +1121,7 @@
}
}
}
-
+
// Add the branch back if the block is more than just an uncond branch.
TII->InsertBranch(*MBB, CurTBB, 0, CurCond);
}
@@ -1135,7 +1134,7 @@
PriorTBB, PriorFBB, PriorCond)) {
// Now we know that there was no fall-through into this block, check to
// see if it has a fall-through into its successor.
- bool CurFallsThru = CanFallThrough(MBB, CurUnAnalyzable, CurTBB, CurFBB,
+ bool CurFallsThru = CanFallThrough(MBB, CurUnAnalyzable, CurTBB, CurFBB,
CurCond);
if (!MBB->isLandingPad()) {
@@ -1151,7 +1150,7 @@
&& (!CurFallsThru || MBB->getNumber() >= PredBB->getNumber())) {
// If the current block doesn't fall through, just move it.
// If the current block can fall through and does not end with a
- // conditional branch, we need to append an unconditional jump to
+ // conditional branch, we need to append an unconditional jump to
// the (current) next block. To avoid a possible compile-time
// infinite loop, move blocks only backward in this case.
// Also, if there are already 2 branches here, we cannot add a third;
@@ -1170,7 +1169,7 @@
}
}
}
-
+
if (!CurFallsThru) {
// Check all successors to see if we can move this block before it.
for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(),
@@ -1178,7 +1177,7 @@
// Analyze the branch at the end of the block before the succ.
MachineBasicBlock *SuccBB = *SI;
MachineFunction::iterator SuccPrev = SuccBB; --SuccPrev;
-
+
// If this block doesn't already fall-through to that successor, and if
// the succ doesn't already have a block that can fall through into it,
// and if the successor isn't an EH destination, we can arrange for the
@@ -1190,7 +1189,7 @@
return OptimizeBlock(MBB);
}
}
-
+
// Okay, there is no really great place to put this block. If, however,
// the block before this one would be a fall-through if this block were
// removed, move this block to the end of the function.
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