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authorNadav Rotem <nadav.rotem@intel.com>2012-07-24 10:51:42 +0000
committerNadav Rotem <nadav.rotem@intel.com>2012-07-24 10:51:42 +0000
commita94d6e87c4c49f2e81b01d66d8bfb591277f8f96 (patch)
tree11026d8db318f33530de45b3abbb9606d0f7ae5e /lib/Transforms/Scalar/SimplifyCFGPass.cpp
parent8899d5c6fb3cf118c5c73eade290b6ebb2b3b850 (diff)
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Clean whitespaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160668 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms/Scalar/SimplifyCFGPass.cpp')
-rw-r--r--lib/Transforms/Scalar/SimplifyCFGPass.cpp54
1 files changed, 27 insertions, 27 deletions
diff --git a/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index 99e236f543..d13e4abff9 100644
--- a/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -67,7 +67,7 @@ static void ChangeToUnreachable(Instruction *I, bool UseLLVMTrap) {
// nodes.
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
(*SI)->removePredecessor(BB);
-
+
// Insert a call to llvm.trap right before this. This turns the undefined
// behavior into a hard fail instead of falling through into random code.
if (UseLLVMTrap) {
@@ -77,7 +77,7 @@ static void ChangeToUnreachable(Instruction *I, bool UseLLVMTrap) {
CallTrap->setDebugLoc(I->getDebugLoc());
}
new UnreachableInst(I->getContext(), I);
-
+
// All instructions after this are dead.
BasicBlock::iterator BBI = I, BBE = BB->end();
while (BBI != BBE) {
@@ -107,13 +107,13 @@ static void ChangeToCall(InvokeInst *II) {
static bool MarkAliveBlocks(BasicBlock *BB,
SmallPtrSet<BasicBlock*, 128> &Reachable) {
-
+
SmallVector<BasicBlock*, 128> Worklist;
Worklist.push_back(BB);
bool Changed = false;
do {
BB = Worklist.pop_back_val();
-
+
if (!Reachable.insert(BB))
continue;
@@ -135,7 +135,7 @@ static bool MarkAliveBlocks(BasicBlock *BB,
break;
}
}
-
+
// Store to undef and store to null are undefined and used to signal that
// they should be changed to unreachable by passes that can't modify the
// CFG.
@@ -144,7 +144,7 @@ static bool MarkAliveBlocks(BasicBlock *BB,
if (SI->isVolatile()) continue;
Value *Ptr = SI->getOperand(1);
-
+
if (isa<UndefValue>(Ptr) ||
(isa<ConstantPointerNull>(Ptr) &&
SI->getPointerAddressSpace() == 0)) {
@@ -180,38 +180,38 @@ static bool MarkAliveBlocks(BasicBlock *BB,
return Changed;
}
-/// RemoveUnreachableBlocksFromFn - Remove blocks that are not reachable, even
-/// if they are in a dead cycle. Return true if a change was made, false
+/// RemoveUnreachableBlocksFromFn - Remove blocks that are not reachable, even
+/// if they are in a dead cycle. Return true if a change was made, false
/// otherwise.
static bool RemoveUnreachableBlocksFromFn(Function &F) {
SmallPtrSet<BasicBlock*, 128> Reachable;
bool Changed = MarkAliveBlocks(F.begin(), Reachable);
-
+
// If there are unreachable blocks in the CFG...
if (Reachable.size() == F.size())
return Changed;
-
+
assert(Reachable.size() < F.size());
NumSimpl += F.size()-Reachable.size();
-
+
// Loop over all of the basic blocks that are not reachable, dropping all of
// their internal references...
for (Function::iterator BB = ++F.begin(), E = F.end(); BB != E; ++BB) {
if (Reachable.count(BB))
continue;
-
+
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
if (Reachable.count(*SI))
(*SI)->removePredecessor(BB);
BB->dropAllReferences();
}
-
+
for (Function::iterator I = ++F.begin(); I != F.end();)
if (!Reachable.count(I))
I = F.getBasicBlockList().erase(I);
else
++I;
-
+
return true;
}
@@ -219,17 +219,17 @@ static bool RemoveUnreachableBlocksFromFn(Function &F) {
/// node) return blocks, merge them together to promote recursive block merging.
static bool MergeEmptyReturnBlocks(Function &F) {
bool Changed = false;
-
+
BasicBlock *RetBlock = 0;
-
+
// Scan all the blocks in the function, looking for empty return blocks.
for (Function::iterator BBI = F.begin(), E = F.end(); BBI != E; ) {
BasicBlock &BB = *BBI++;
-
+
// Only look at return blocks.
ReturnInst *Ret = dyn_cast<ReturnInst>(BB.getTerminator());
if (Ret == 0) continue;
-
+
// Only look at the block if it is empty or the only other thing in it is a
// single PHI node that is the operand to the return.
if (Ret != &BB.front()) {
@@ -251,21 +251,21 @@ static bool MergeEmptyReturnBlocks(Function &F) {
RetBlock = &BB;
continue;
}
-
+
// Otherwise, we found a duplicate return block. Merge the two.
Changed = true;
-
+
// Case when there is no input to the return or when the returned values
// agree is trivial. Note that they can't agree if there are phis in the
// blocks.
if (Ret->getNumOperands() == 0 ||
- Ret->getOperand(0) ==
+ Ret->getOperand(0) ==
cast<ReturnInst>(RetBlock->getTerminator())->getOperand(0)) {
BB.replaceAllUsesWith(RetBlock);
BB.eraseFromParent();
continue;
}
-
+
// If the canonical return block has no PHI node, create one now.
PHINode *RetBlockPHI = dyn_cast<PHINode>(RetBlock->begin());
if (RetBlockPHI == 0) {
@@ -274,12 +274,12 @@ static bool MergeEmptyReturnBlocks(Function &F) {
RetBlockPHI = PHINode::Create(Ret->getOperand(0)->getType(),
std::distance(PB, PE), "merge",
&RetBlock->front());
-
+
for (pred_iterator PI = PB; PI != PE; ++PI)
RetBlockPHI->addIncoming(InVal, *PI);
RetBlock->getTerminator()->setOperand(0, RetBlockPHI);
}
-
+
// Turn BB into a block that just unconditionally branches to the return
// block. This handles the case when the two return blocks have a common
// predecessor but that return different things.
@@ -287,7 +287,7 @@ static bool MergeEmptyReturnBlocks(Function &F) {
BB.getTerminator()->eraseFromParent();
BranchInst::Create(RetBlock, &BB);
}
-
+
return Changed;
}
@@ -298,7 +298,7 @@ static bool IterativeSimplifyCFG(Function &F, const TargetData *TD) {
bool LocalChange = true;
while (LocalChange) {
LocalChange = false;
-
+
// Loop over all of the basic blocks and remove them if they are unneeded...
//
for (Function::iterator BBIt = F.begin(); BBIt != F.end(); ) {
@@ -327,7 +327,7 @@ bool CFGSimplifyPass::runOnFunction(Function &F) {
// IterativeSimplifyCFG can (rarely) make some loops dead. If this happens,
// RemoveUnreachableBlocksFromFn is needed to nuke them, which means we should
// iterate between the two optimizations. We structure the code like this to
- // avoid reruning IterativeSimplifyCFG if the second pass of
+ // avoid reruning IterativeSimplifyCFG if the second pass of
// RemoveUnreachableBlocksFromFn doesn't do anything.
if (!RemoveUnreachableBlocksFromFn(F))
return true;