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Diffstat (limited to 'lib/Transforms/Utils/LCSSA.cpp')
-rw-r--r--lib/Transforms/Utils/LCSSA.cpp76
1 files changed, 41 insertions, 35 deletions
diff --git a/lib/Transforms/Utils/LCSSA.cpp b/lib/Transforms/Utils/LCSSA.cpp
index 9d40b6989d6e..b4b2e148dfbb 100644
--- a/lib/Transforms/Utils/LCSSA.cpp
+++ b/lib/Transforms/Utils/LCSSA.cpp
@@ -31,8 +31,10 @@
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/GlobalsModRef.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
@@ -64,6 +66,13 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
PredIteratorCache &PredCache, LoopInfo *LI) {
SmallVector<Use *, 16> UsesToRewrite;
+ // Tokens cannot be used in PHI nodes, so we skip over them.
+ // We can run into tokens which are live out of a loop with catchswitch
+ // instructions in Windows EH if the catchswitch has one catchpad which
+ // is inside the loop and another which is not.
+ if (Inst.getType()->isTokenTy())
+ return false;
+
BasicBlock *InstBB = Inst.getParent();
for (Use &U : Inst.uses()) {
@@ -84,9 +93,8 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
// Invoke instructions are special in that their result value is not available
// along their unwind edge. The code below tests to see whether DomBB
- // dominates
- // the value, so adjust DomBB to the normal destination block, which is
- // effectively where the value is first usable.
+ // dominates the value, so adjust DomBB to the normal destination block,
+ // which is effectively where the value is first usable.
BasicBlock *DomBB = Inst.getParent();
if (InvokeInst *Inv = dyn_cast<InvokeInst>(&Inst))
DomBB = Inv->getNormalDest();
@@ -101,10 +109,7 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
// Insert the LCSSA phi's into all of the exit blocks dominated by the
// value, and add them to the Phi's map.
- for (SmallVectorImpl<BasicBlock *>::const_iterator BBI = ExitBlocks.begin(),
- BBE = ExitBlocks.end();
- BBI != BBE; ++BBI) {
- BasicBlock *ExitBB = *BBI;
+ for (BasicBlock *ExitBB : ExitBlocks) {
if (!DT.dominates(DomNode, DT.getNode(ExitBB)))
continue;
@@ -113,7 +118,7 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
continue;
PHINode *PN = PHINode::Create(Inst.getType(), PredCache.size(ExitBB),
- Inst.getName() + ".lcssa", ExitBB->begin());
+ Inst.getName() + ".lcssa", &ExitBB->front());
// Add inputs from inside the loop for this PHI.
for (BasicBlock *Pred : PredCache.get(ExitBB)) {
@@ -148,26 +153,26 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
// Rewrite all uses outside the loop in terms of the new PHIs we just
// inserted.
- for (unsigned i = 0, e = UsesToRewrite.size(); i != e; ++i) {
+ for (Use *UseToRewrite : UsesToRewrite) {
// If this use is in an exit block, rewrite to use the newly inserted PHI.
// This is required for correctness because SSAUpdate doesn't handle uses in
// the same block. It assumes the PHI we inserted is at the end of the
// block.
- Instruction *User = cast<Instruction>(UsesToRewrite[i]->getUser());
+ Instruction *User = cast<Instruction>(UseToRewrite->getUser());
BasicBlock *UserBB = User->getParent();
if (PHINode *PN = dyn_cast<PHINode>(User))
- UserBB = PN->getIncomingBlock(*UsesToRewrite[i]);
+ UserBB = PN->getIncomingBlock(*UseToRewrite);
if (isa<PHINode>(UserBB->begin()) && isExitBlock(UserBB, ExitBlocks)) {
// Tell the VHs that the uses changed. This updates SCEV's caches.
- if (UsesToRewrite[i]->get()->hasValueHandle())
- ValueHandleBase::ValueIsRAUWd(*UsesToRewrite[i], UserBB->begin());
- UsesToRewrite[i]->set(UserBB->begin());
+ if (UseToRewrite->get()->hasValueHandle())
+ ValueHandleBase::ValueIsRAUWd(*UseToRewrite, &UserBB->front());
+ UseToRewrite->set(&UserBB->front());
continue;
}
// Otherwise, do full PHI insertion.
- SSAUpdate.RewriteUse(*UsesToRewrite[i]);
+ SSAUpdate.RewriteUse(*UseToRewrite);
}
// Post process PHI instructions that were inserted into another disjoint loop
@@ -190,10 +195,9 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
}
// Remove PHI nodes that did not have any uses rewritten.
- for (unsigned i = 0, e = AddedPHIs.size(); i != e; ++i) {
- if (AddedPHIs[i]->use_empty())
- AddedPHIs[i]->eraseFromParent();
- }
+ for (PHINode *PN : AddedPHIs)
+ if (PN->use_empty())
+ PN->eraseFromParent();
return true;
}
@@ -205,8 +209,8 @@ blockDominatesAnExit(BasicBlock *BB,
DominatorTree &DT,
const SmallVectorImpl<BasicBlock *> &ExitBlocks) {
DomTreeNode *DomNode = DT.getNode(BB);
- for (unsigned i = 0, e = ExitBlocks.size(); i != e; ++i)
- if (DT.dominates(DomNode, DT.getNode(ExitBlocks[i])))
+ for (BasicBlock *ExitBB : ExitBlocks)
+ if (DT.dominates(DomNode, DT.getNode(ExitBB)))
return true;
return false;
@@ -227,25 +231,22 @@ bool llvm::formLCSSA(Loop &L, DominatorTree &DT, LoopInfo *LI,
// Look at all the instructions in the loop, checking to see if they have uses
// outside the loop. If so, rewrite those uses.
- for (Loop::block_iterator BBI = L.block_begin(), BBE = L.block_end();
- BBI != BBE; ++BBI) {
- BasicBlock *BB = *BBI;
-
+ for (BasicBlock *BB : L.blocks()) {
// For large loops, avoid use-scanning by using dominance information: In
// particular, if a block does not dominate any of the loop exits, then none
// of the values defined in the block could be used outside the loop.
if (!blockDominatesAnExit(BB, DT, ExitBlocks))
continue;
- for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
+ for (Instruction &I : *BB) {
// Reject two common cases fast: instructions with no uses (like stores)
// and instructions with one use that is in the same block as this.
- if (I->use_empty() ||
- (I->hasOneUse() && I->user_back()->getParent() == BB &&
- !isa<PHINode>(I->user_back())))
+ if (I.use_empty() ||
+ (I.hasOneUse() && I.user_back()->getParent() == BB &&
+ !isa<PHINode>(I.user_back())))
continue;
- Changed |= processInstruction(L, *I, DT, ExitBlocks, PredCache, LI);
+ Changed |= processInstruction(L, I, DT, ExitBlocks, PredCache, LI);
}
}
@@ -266,8 +267,8 @@ bool llvm::formLCSSARecursively(Loop &L, DominatorTree &DT, LoopInfo *LI,
bool Changed = false;
// Recurse depth-first through inner loops.
- for (Loop::iterator I = L.begin(), E = L.end(); I != E; ++I)
- Changed |= formLCSSARecursively(**I, DT, LI, SE);
+ for (Loop *SubLoop : L.getSubLoops())
+ Changed |= formLCSSARecursively(*SubLoop, DT, LI, SE);
Changed |= formLCSSA(L, DT, LI, SE);
return Changed;
@@ -296,8 +297,10 @@ struct LCSSA : public FunctionPass {
AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<LoopInfoWrapperPass>();
AU.addPreservedID(LoopSimplifyID);
- AU.addPreserved<AliasAnalysis>();
- AU.addPreserved<ScalarEvolution>();
+ AU.addPreserved<AAResultsWrapperPass>();
+ AU.addPreserved<GlobalsAAWrapperPass>();
+ AU.addPreserved<ScalarEvolutionWrapperPass>();
+ AU.addPreserved<SCEVAAWrapperPass>();
}
};
}
@@ -306,6 +309,8 @@ char LCSSA::ID = 0;
INITIALIZE_PASS_BEGIN(LCSSA, "lcssa", "Loop-Closed SSA Form Pass", false, false)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(GlobalsAAWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(SCEVAAWrapperPass)
INITIALIZE_PASS_END(LCSSA, "lcssa", "Loop-Closed SSA Form Pass", false, false)
Pass *llvm::createLCSSAPass() { return new LCSSA(); }
@@ -317,7 +322,8 @@ bool LCSSA::runOnFunction(Function &F) {
bool Changed = false;
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
- SE = getAnalysisIfAvailable<ScalarEvolution>();
+ auto *SEWP = getAnalysisIfAvailable<ScalarEvolutionWrapperPass>();
+ SE = SEWP ? &SEWP->getSE() : nullptr;
// Simplify each loop nest in the function.
for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-21 19:49:22 +0000