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-rw-r--r--lib/Transforms/Utils/BasicBlockUtils.cpp10
-rw-r--r--lib/Transforms/Utils/BreakCriticalEdges.cpp3
-rw-r--r--lib/Transforms/Utils/BuildLibCalls.cpp6
-rw-r--r--lib/Transforms/Utils/InlineFunction.cpp563
-rw-r--r--lib/Transforms/Utils/Local.cpp71
-rw-r--r--lib/Transforms/Utils/PromoteMemoryToRegister.cpp12
-rw-r--r--lib/Transforms/Utils/SSAUpdater.cpp26
-rw-r--r--lib/Transforms/Utils/SimplifyCFG.cpp273
8 files changed, 755 insertions, 209 deletions
diff --git a/lib/Transforms/Utils/BasicBlockUtils.cpp b/lib/Transforms/Utils/BasicBlockUtils.cpp
index c705cc5..92464e8 100644
--- a/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -542,11 +542,9 @@ ReturnInst *llvm::FoldReturnIntoUncondBranch(ReturnInst *RI, BasicBlock *BB,
/// GetFirstDebugLocInBasicBlock - Return first valid DebugLoc entry in a
/// given basic block.
DebugLoc llvm::GetFirstDebugLocInBasicBlock(const BasicBlock *BB) {
- for (BasicBlock::const_iterator BI = BB->begin(), BE = BB->end();
- BI != BE; ++BI) {
- DebugLoc DL = BI->getDebugLoc();
- if (!DL.isUnknown())
- return DL;
- }
+ if (const Instruction *I = BB->getFirstNonPHI())
+ return I->getDebugLoc();
+ // Scanning entire block may be too expensive, if the first instruction
+ // does not have valid location info.
return DebugLoc();
}
diff --git a/lib/Transforms/Utils/BreakCriticalEdges.cpp b/lib/Transforms/Utils/BreakCriticalEdges.cpp
index caf2aeb..d6206a3 100644
--- a/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -180,7 +180,8 @@ BasicBlock *llvm::SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum,
BasicBlock *NewBB = BasicBlock::Create(TI->getContext(),
TIBB->getName() + "." + DestBB->getName() + "_crit_edge");
// Create our unconditional branch.
- BranchInst::Create(DestBB, NewBB);
+ BranchInst *NewBI = BranchInst::Create(DestBB, NewBB);
+ NewBI->setDebugLoc(TI->getDebugLoc());
// Branch to the new block, breaking the edge.
TI->setSuccessor(SuccNum, NewBB);
diff --git a/lib/Transforms/Utils/BuildLibCalls.cpp b/lib/Transforms/Utils/BuildLibCalls.cpp
index 4a90751..14bb17f 100644
--- a/lib/Transforms/Utils/BuildLibCalls.cpp
+++ b/lib/Transforms/Utils/BuildLibCalls.cpp
@@ -362,12 +362,8 @@ bool SimplifyFortifiedLibCalls::fold(CallInst *CI, const TargetData *TD) {
Function *Callee = CI->getCalledFunction();
StringRef Name = Callee->getName();
const FunctionType *FT = Callee->getFunctionType();
- BasicBlock *BB = CI->getParent();
LLVMContext &Context = CI->getParent()->getContext();
- IRBuilder<> B(Context);
-
- // Set the builder to the instruction after the call.
- B.SetInsertPoint(BB, CI);
+ IRBuilder<> B(CI);
if (Name == "__memcpy_chk") {
// Check if this has the right signature.
diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index 7d17909..8416170 100644
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -10,6 +10,13 @@
// This file implements inlining of a function into a call site, resolving
// parameters and the return value as appropriate.
//
+// The code in this file for handling inlines through invoke
+// instructions preserves semantics only under some assumptions about
+// the behavior of unwinders which correspond to gcc-style libUnwind
+// exception personality functions. Eventually the IR will be
+// improved to make this unnecessary, but until then, this code is
+// marked [LIBUNWIND].
+//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Cloning.h"
@@ -28,6 +35,7 @@
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/CallSite.h"
+#include "llvm/Support/IRBuilder.h"
using namespace llvm;
bool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI) {
@@ -37,6 +45,372 @@ bool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI) {
return InlineFunction(CallSite(II), IFI);
}
+/// [LIBUNWIND] Look for an llvm.eh.exception call in the given block.
+static EHExceptionInst *findExceptionInBlock(BasicBlock *bb) {
+ for (BasicBlock::iterator i = bb->begin(), e = bb->end(); i != e; i++) {
+ EHExceptionInst *exn = dyn_cast<EHExceptionInst>(i);
+ if (exn) return exn;
+ }
+
+ return 0;
+}
+
+/// [LIBUNWIND] Look for the 'best' llvm.eh.selector instruction for
+/// the given llvm.eh.exception call.
+static EHSelectorInst *findSelectorForException(EHExceptionInst *exn) {
+ BasicBlock *exnBlock = exn->getParent();
+
+ EHSelectorInst *outOfBlockSelector = 0;
+ for (Instruction::use_iterator
+ ui = exn->use_begin(), ue = exn->use_end(); ui != ue; ++ui) {
+ EHSelectorInst *sel = dyn_cast<EHSelectorInst>(*ui);
+ if (!sel) continue;
+
+ // Immediately accept an eh.selector in the same block as the
+ // excepton call.
+ if (sel->getParent() == exnBlock) return sel;
+
+ // Otherwise, use the first selector we see.
+ if (!outOfBlockSelector) outOfBlockSelector = sel;
+ }
+
+ return outOfBlockSelector;
+}
+
+/// [LIBUNWIND] Find the (possibly absent) call to @llvm.eh.selector
+/// in the given landing pad. In principle, llvm.eh.exception is
+/// required to be in the landing pad; in practice, SplitCriticalEdge
+/// can break that invariant, and then inlining can break it further.
+/// There's a real need for a reliable solution here, but until that
+/// happens, we have some fragile workarounds here.
+static EHSelectorInst *findSelectorForLandingPad(BasicBlock *lpad) {
+ // Look for an exception call in the actual landing pad.
+ EHExceptionInst *exn = findExceptionInBlock(lpad);
+ if (exn) return findSelectorForException(exn);
+
+ // Okay, if that failed, look for one in an obvious successor. If
+ // we find one, we'll fix the IR by moving things back to the
+ // landing pad.
+
+ bool dominates = true; // does the lpad dominate the exn call
+ BasicBlock *nonDominated = 0; // if not, the first non-dominated block
+ BasicBlock *lastDominated = 0; // and the block which branched to it
+
+ BasicBlock *exnBlock = lpad;
+
+ // We need to protect against lpads that lead into infinite loops.
+ SmallPtrSet<BasicBlock*,4> visited;
+ visited.insert(exnBlock);
+
+ do {
+ // We're not going to apply this hack to anything more complicated
+ // than a series of unconditional branches, so if the block
+ // doesn't terminate in an unconditional branch, just fail. More
+ // complicated cases can arise when, say, sinking a call into a
+ // split unwind edge and then inlining it; but that can do almost
+ // *anything* to the CFG, including leaving the selector
+ // completely unreachable. The only way to fix that properly is
+ // to (1) prohibit transforms which move the exception or selector
+ // values away from the landing pad, e.g. by producing them with
+ // instructions that are pinned to an edge like a phi, or
+ // producing them with not-really-instructions, and (2) making
+ // transforms which split edges deal with that.
+ BranchInst *branch = dyn_cast<BranchInst>(&exnBlock->back());
+ if (!branch || branch->isConditional()) return 0;
+
+ BasicBlock *successor = branch->getSuccessor(0);
+
+ // Fail if we found an infinite loop.
+ if (!visited.insert(successor)) return 0;
+
+ // If the successor isn't dominated by exnBlock:
+ if (!successor->getSinglePredecessor()) {
+ // We don't want to have to deal with threading the exception
+ // through multiple levels of phi, so give up if we've already
+ // followed a non-dominating edge.
+ if (!dominates) return 0;
+
+ // Otherwise, remember this as a non-dominating edge.
+ dominates = false;
+ nonDominated = successor;
+ lastDominated = exnBlock;
+ }
+
+ exnBlock = successor;
+
+ // Can we stop here?
+ exn = findExceptionInBlock(exnBlock);
+ } while (!exn);
+
+ // Look for a selector call for the exception we found.
+ EHSelectorInst *selector = findSelectorForException(exn);
+ if (!selector) return 0;
+
+ // The easy case is when the landing pad still dominates the
+ // exception call, in which case we can just move both calls back to
+ // the landing pad.
+ if (dominates) {
+ selector->moveBefore(lpad->getFirstNonPHI());
+ exn->moveBefore(selector);
+ return selector;
+ }
+
+ // Otherwise, we have to split at the first non-dominating block.
+ // The CFG looks basically like this:
+ // lpad:
+ // phis_0
+ // insnsAndBranches_1
+ // br label %nonDominated
+ // nonDominated:
+ // phis_2
+ // insns_3
+ // %exn = call i8* @llvm.eh.exception()
+ // insnsAndBranches_4
+ // %selector = call @llvm.eh.selector(i8* %exn, ...
+ // We need to turn this into:
+ // lpad:
+ // phis_0
+ // %exn0 = call i8* @llvm.eh.exception()
+ // %selector0 = call @llvm.eh.selector(i8* %exn0, ...
+ // insnsAndBranches_1
+ // br label %split // from lastDominated
+ // nonDominated:
+ // phis_2 (without edge from lastDominated)
+ // %exn1 = call i8* @llvm.eh.exception()
+ // %selector1 = call i8* @llvm.eh.selector(i8* %exn1, ...
+ // br label %split
+ // split:
+ // phis_2 (edge from lastDominated, edge from split)
+ // %exn = phi ...
+ // %selector = phi ...
+ // insns_3
+ // insnsAndBranches_4
+
+ assert(nonDominated);
+ assert(lastDominated);
+
+ // First, make clones of the intrinsics to go in lpad.
+ EHExceptionInst *lpadExn = cast<EHExceptionInst>(exn->clone());
+ EHSelectorInst *lpadSelector = cast<EHSelectorInst>(selector->clone());
+ lpadSelector->setArgOperand(0, lpadExn);
+ lpadSelector->insertBefore(lpad->getFirstNonPHI());
+ lpadExn->insertBefore(lpadSelector);
+
+ // Split the non-dominated block.
+ BasicBlock *split =
+ nonDominated->splitBasicBlock(nonDominated->getFirstNonPHI(),
+ nonDominated->getName() + ".lpad-fix");
+
+ // Redirect the last dominated branch there.
+ cast<BranchInst>(lastDominated->back()).setSuccessor(0, split);
+
+ // Move the existing intrinsics to the end of the old block.
+ selector->moveBefore(&nonDominated->back());
+ exn->moveBefore(selector);
+
+ Instruction *splitIP = &split->front();
+
+ // For all the phis in nonDominated, make a new phi in split to join
+ // that phi with the edge from lastDominated.
+ for (BasicBlock::iterator
+ i = nonDominated->begin(), e = nonDominated->end(); i != e; ++i) {
+ PHINode *phi = dyn_cast<PHINode>(i);
+ if (!phi) break;
+
+ PHINode *splitPhi = PHINode::Create(phi->getType(), 2, phi->getName(),
+ splitIP);
+ phi->replaceAllUsesWith(splitPhi);
+ splitPhi->addIncoming(phi, nonDominated);
+ splitPhi->addIncoming(phi->removeIncomingValue(lastDominated),
+ lastDominated);
+ }
+
+ // Make new phis for the exception and selector.
+ PHINode *exnPhi = PHINode::Create(exn->getType(), 2, "", splitIP);
+ exn->replaceAllUsesWith(exnPhi);
+ selector->setArgOperand(0, exn); // except for this use
+ exnPhi->addIncoming(exn, nonDominated);
+ exnPhi->addIncoming(lpadExn, lastDominated);
+
+ PHINode *selectorPhi = PHINode::Create(selector->getType(), 2, "", splitIP);
+ selector->replaceAllUsesWith(selectorPhi);
+ selectorPhi->addIncoming(selector, nonDominated);
+ selectorPhi->addIncoming(lpadSelector, lastDominated);
+
+ return lpadSelector;
+}
+
+namespace {
+ /// A class for recording information about inlining through an invoke.
+ class InvokeInliningInfo {
+ BasicBlock *OuterUnwindDest;
+ EHSelectorInst *OuterSelector;
+ BasicBlock *InnerUnwindDest;
+ PHINode *InnerExceptionPHI;
+ PHINode *InnerSelectorPHI;
+ SmallVector<Value*, 8> UnwindDestPHIValues;
+
+ public:
+ InvokeInliningInfo(InvokeInst *II) :
+ OuterUnwindDest(II->getUnwindDest()), OuterSelector(0),
+ InnerUnwindDest(0), InnerExceptionPHI(0), InnerSelectorPHI(0) {
+
+ // If there are PHI nodes in the unwind destination block, we
+ // need to keep track of which values came into them from the
+ // invoke before removing the edge from this block.
+ llvm::BasicBlock *invokeBB = II->getParent();
+ for (BasicBlock::iterator I = OuterUnwindDest->begin();
+ isa<PHINode>(I); ++I) {
+ // Save the value to use for this edge.
+ PHINode *phi = cast<PHINode>(I);
+ UnwindDestPHIValues.push_back(phi->getIncomingValueForBlock(invokeBB));
+ }
+ }
+
+ /// The outer unwind destination is the target of unwind edges
+ /// introduced for calls within the inlined function.
+ BasicBlock *getOuterUnwindDest() const {
+ return OuterUnwindDest;
+ }
+
+ EHSelectorInst *getOuterSelector() {
+ if (!OuterSelector)
+ OuterSelector = findSelectorForLandingPad(OuterUnwindDest);
+ return OuterSelector;
+ }
+
+ BasicBlock *getInnerUnwindDest();
+
+ bool forwardEHResume(CallInst *call, BasicBlock *src);
+
+ /// Add incoming-PHI values to the unwind destination block for
+ /// the given basic block, using the values for the original
+ /// invoke's source block.
+ void addIncomingPHIValuesFor(BasicBlock *BB) const {
+ addIncomingPHIValuesForInto(BB, OuterUnwindDest);
+ }
+
+ void addIncomingPHIValuesForInto(BasicBlock *src, BasicBlock *dest) const {
+ BasicBlock::iterator I = dest->begin();
+ for (unsigned i = 0, e = UnwindDestPHIValues.size(); i != e; ++i, ++I) {
+ PHINode *phi = cast<PHINode>(I);
+ phi->addIncoming(UnwindDestPHIValues[i], src);
+ }
+ }
+ };
+}
+
+/// Get or create a target for the branch out of rewritten calls to
+/// llvm.eh.resume.
+BasicBlock *InvokeInliningInfo::getInnerUnwindDest() {
+ if (InnerUnwindDest) return InnerUnwindDest;
+
+ // Find and hoist the llvm.eh.exception and llvm.eh.selector calls
+ // in the outer landing pad to immediately following the phis.
+ EHSelectorInst *selector = getOuterSelector();
+ if (!selector) return 0;
+
+ // The call to llvm.eh.exception *must* be in the landing pad.
+ Instruction *exn = cast<Instruction>(selector->getArgOperand(0));
+ assert(exn->getParent() == OuterUnwindDest);
+
+ // TODO: recognize when we've already done this, so that we don't
+ // get a linear number of these when inlining calls into lots of
+ // invokes with the same landing pad.
+
+ // Do the hoisting.
+ Instruction *splitPoint = exn->getParent()->getFirstNonPHI();
+ assert(splitPoint != selector && "selector-on-exception dominance broken!");
+ if (splitPoint == exn) {
+ selector->removeFromParent();
+ selector->insertAfter(exn);
+ splitPoint = selector->getNextNode();
+ } else {
+ exn->moveBefore(splitPoint);
+ selector->moveBefore(splitPoint);
+ }
+
+ // Split the landing pad.
+ InnerUnwindDest = OuterUnwindDest->splitBasicBlock(splitPoint,
+ OuterUnwindDest->getName() + ".body");
+
+ // The number of incoming edges we expect to the inner landing pad.
+ const unsigned phiCapacity = 2;
+
+ // Create corresponding new phis for all the phis in the outer landing pad.
+ BasicBlock::iterator insertPoint = InnerUnwindDest->begin();
+ BasicBlock::iterator I = OuterUnwindDest->begin();
+ for (unsigned i = 0, e = UnwindDestPHIValues.size(); i != e; ++i, ++I) {
+ PHINode *outerPhi = cast<PHINode>(I);
+ PHINode *innerPhi = PHINode::Create(outerPhi->getType(), phiCapacity,
+ outerPhi->getName() + ".lpad-body",
+ insertPoint);
+ outerPhi->replaceAllUsesWith(innerPhi);
+ innerPhi->addIncoming(outerPhi, OuterUnwindDest);
+ }
+
+ // Create a phi for the exception value...
+ InnerExceptionPHI = PHINode::Create(exn->getType(), phiCapacity,
+ "exn.lpad-body", insertPoint);
+ exn->replaceAllUsesWith(InnerExceptionPHI);
+ selector->setArgOperand(0, exn); // restore this use
+ InnerExceptionPHI->addIncoming(exn, OuterUnwindDest);
+
+ // ...and the selector.
+ InnerSelectorPHI = PHINode::Create(selector->getType(), phiCapacity,
+ "selector.lpad-body", insertPoint);
+ selector->replaceAllUsesWith(InnerSelectorPHI);
+ InnerSelectorPHI->addIncoming(selector, OuterUnwindDest);
+
+ // All done.
+ return InnerUnwindDest;
+}
+
+/// [LIBUNWIND] Try to forward the given call, which logically occurs
+/// at the end of the given block, as a branch to the inner unwind
+/// block. Returns true if the call was forwarded.
+bool InvokeInliningInfo::forwardEHResume(CallInst *call, BasicBlock *src) {
+ // First, check whether this is a call to the intrinsic.
+ Function *fn = dyn_cast<Function>(call->getCalledValue());
+ if (!fn || fn->getName() != "llvm.eh.resume")
+ return false;
+
+ // At this point, we need to return true on all paths, because
+ // otherwise we'll construct an invoke of the intrinsic, which is
+ // not well-formed.
+
+ // Try to find or make an inner unwind dest, which will fail if we
+ // can't find a selector call for the outer unwind dest.
+ BasicBlock *dest = getInnerUnwindDest();
+ bool hasSelector = (dest != 0);
+
+ // If we failed, just use the outer unwind dest, dropping the
+ // exception and selector on the floor.
+ if (!hasSelector)
+ dest = OuterUnwindDest;
+
+ // Make a branch.
+ BranchInst::Create(dest, src);
+
+ // Update the phis in the destination. They were inserted in an
+ // order which makes this work.
+ addIncomingPHIValuesForInto(src, dest);
+
+ if (hasSelector) {
+ InnerExceptionPHI->addIncoming(call->getArgOperand(0), src);
+ InnerSelectorPHI->addIncoming(call->getArgOperand(1), src);
+ }
+
+ return true;
+}
+
+/// [LIBUNWIND] Check whether this selector is "only cleanups":
+/// call i32 @llvm.eh.selector(blah, blah, i32 0)
+static bool isCleanupOnlySelector(EHSelectorInst *selector) {
+ if (selector->getNumArgOperands() != 3) return false;
+ ConstantInt *val = dyn_cast<ConstantInt>(selector->getArgOperand(2));
+ return (val && val->isZero());
+}
/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into
/// an invoke, we have to turn all of the calls that can throw into
@@ -44,9 +418,9 @@ bool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI) {
/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI
/// nodes in that block with the values specified in InvokeDestPHIValues.
///
-static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
- BasicBlock *InvokeDest,
- const SmallVectorImpl<Value*> &InvokeDestPHIValues) {
+/// Returns true to indicate that the next block should be skipped.
+static bool HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
+ InvokeInliningInfo &Invoke) {
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
Instruction *I = BBI++;
@@ -54,6 +428,38 @@ static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
// instructions require no special handling.
CallInst *CI = dyn_cast<CallInst>(I);
if (CI == 0) continue;
+
+ // LIBUNWIND: merge selector instructions.
+ if (EHSelectorInst *Inner = dyn_cast<EHSelectorInst>(CI)) {
+ EHSelectorInst *Outer = Invoke.getOuterSelector();
+ if (!Outer) continue;
+
+ bool innerIsOnlyCleanup = isCleanupOnlySelector(Inner);
+ bool outerIsOnlyCleanup = isCleanupOnlySelector(Outer);
+
+ // If both selectors contain only cleanups, we don't need to do
+ // anything. TODO: this is really just a very specific instance
+ // of a much more general optimization.
+ if (innerIsOnlyCleanup && outerIsOnlyCleanup) continue;
+
+ // Otherwise, we just append the outer selector to the inner selector.
+ SmallVector<Value*, 16> NewSelector;
+ for (unsigned i = 0, e = Inner->getNumArgOperands(); i != e; ++i)
+ NewSelector.push_back(Inner->getArgOperand(i));
+ for (unsigned i = 2, e = Outer->getNumArgOperands(); i != e; ++i)
+ NewSelector.push_back(Outer->getArgOperand(i));
+
+ CallInst *NewInner = CallInst::Create(Inner->getCalledValue(),
+ NewSelector.begin(),
+ NewSelector.end(),
+ "",
+ Inner);
+ // No need to copy attributes, calling convention, etc.
+ NewInner->takeName(Inner);
+ Inner->replaceAllUsesWith(NewInner);
+ Inner->eraseFromParent();
+ continue;
+ }
// If this call cannot unwind, don't convert it to an invoke.
if (CI->doesNotThrow())
@@ -62,37 +468,45 @@ static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
// Convert this function call into an invoke instruction.
// First, split the basic block.
BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");
-
- // Next, create the new invoke instruction, inserting it at the end
- // of the old basic block.
+
+ // Delete the unconditional branch inserted by splitBasicBlock
+ BB->getInstList().pop_back();
+
+ // LIBUNWIND: If this is a call to @llvm.eh.resume, just branch
+ // directly to the new landing pad.
+ if (Invoke.forwardEHResume(CI, BB)) {
+ // TODO: 'Split' is now unreachable; clean it up.
+
+ // We want to leave the original call intact so that the call
+ // graph and other structures won't get misled. We also have to
+ // avoid processing the next block, or we'll iterate here forever.
+ return true;
+ }
+
+ // Otherwise, create the new invoke instruction.
ImmutableCallSite CS(CI);
SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end());
InvokeInst *II =
- InvokeInst::Create(CI->getCalledValue(), Split, InvokeDest,
+ InvokeInst::Create(CI->getCalledValue(), Split,
+ Invoke.getOuterUnwindDest(),
InvokeArgs.begin(), InvokeArgs.end(),
- CI->getName(), BB->getTerminator());
+ CI->getName(), BB);
II->setCallingConv(CI->getCallingConv());
II->setAttributes(CI->getAttributes());
// Make sure that anything using the call now uses the invoke! This also
// updates the CallGraph if present, because it uses a WeakVH.
CI->replaceAllUsesWith(II);
-
- // Delete the unconditional branch inserted by splitBasicBlock
- BB->getInstList().pop_back();
+
Split->getInstList().pop_front(); // Delete the original call
-
+
// Update any PHI nodes in the exceptional block to indicate that
// there is now a new entry in them.
- unsigned i = 0;
- for (BasicBlock::iterator I = InvokeDest->begin();
- isa<PHINode>(I); ++I, ++i)
- cast<PHINode>(I)->addIncoming(InvokeDestPHIValues[i], BB);
-
- // This basic block is now complete, the caller will continue scanning the
- // next one.
- return;
+ Invoke.addIncomingPHIValuesFor(BB);
+ return false;
}
+
+ return false;
}
@@ -106,17 +520,6 @@ static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
ClonedCodeInfo &InlinedCodeInfo) {
BasicBlock *InvokeDest = II->getUnwindDest();
- SmallVector<Value*, 8> InvokeDestPHIValues;
-
- // If there are PHI nodes in the unwind destination block, we need to
- // keep track of which values came into them from this invoke, then remove
- // the entry for this block.
- BasicBlock *InvokeBlock = II->getParent();
- for (BasicBlock::iterator I = InvokeDest->begin(); isa<PHINode>(I); ++I) {
- PHINode *PN = cast<PHINode>(I);
- // Save the value to use for this edge.
- InvokeDestPHIValues.push_back(PN->getIncomingValueForBlock(InvokeBlock));
- }
Function *Caller = FirstNewBlock->getParent();
@@ -132,11 +535,17 @@ static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
InvokeDest->removePredecessor(II->getParent());
return;
}
+
+ InvokeInliningInfo Invoke(II);
for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){
if (InlinedCodeInfo.ContainsCalls)
- HandleCallsInBlockInlinedThroughInvoke(BB, InvokeDest,
- InvokeDestPHIValues);
+ if (HandleCallsInBlockInlinedThroughInvoke(BB, Invoke)) {
+ // Honor a request to skip the next block. We don't need to
+ // consider UnwindInsts in this case either.
+ ++BB;
+ continue;
+ }
if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
// An UnwindInst requires special handling when it gets inlined into an
@@ -150,12 +559,7 @@ static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
// Update any PHI nodes in the exceptional block to indicate that
// there is now a new entry in them.
- unsigned i = 0;
- for (BasicBlock::iterator I = InvokeDest->begin();
- isa<PHINode>(I); ++I, ++i) {
- PHINode *PN = cast<PHINode>(I);
- PN->addIncoming(InvokeDestPHIValues[i], BB);
- }
+ Invoke.addIncomingPHIValuesFor(BB);
}
}
@@ -299,21 +703,48 @@ static Value *HandleByValArgument(Value *Arg, Instruction *TheCall,
ConstantInt::get(Type::getInt32Ty(Context), 1),
ConstantInt::getFalse(Context) // isVolatile
};
- CallInst *TheMemCpy =
- CallInst::Create(MemCpyFn, CallArgs, CallArgs+5, "", TheCall);
-
- // If we have a call graph, update it.
- if (CallGraph *CG = IFI.CG) {
- CallGraphNode *MemCpyCGN = CG->getOrInsertFunction(MemCpyFn);
- CallGraphNode *CallerNode = (*CG)[Caller];
- CallerNode->addCalledFunction(TheMemCpy, MemCpyCGN);
- }
+ CallInst::Create(MemCpyFn, CallArgs, CallArgs+5, "", TheCall);
// Uses of the argument in the function should use our new alloca
// instead.
return NewAlloca;
}
+// isUsedByLifetimeMarker - Check whether this Value is used by a lifetime
+// intrinsic.
+static bool isUsedByLifetimeMarker(Value *V) {
+ for (Value::use_iterator UI = V->use_begin(), UE = V->use_end(); UI != UE;
+ ++UI) {
+ if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(*UI)) {
+ switch (II->getIntrinsicID()) {
+ default: break;
+ case Intrinsic::lifetime_start:
+ case Intrinsic::lifetime_end:
+ return true;
+ }
+ }
+ }
+ return false;
+}
+
+// hasLifetimeMarkers - Check whether the given alloca already has
+// lifetime.start or lifetime.end intrinsics.
+static bool hasLifetimeMarkers(AllocaInst *AI) {
+ const Type *Int8PtrTy = Type::getInt8PtrTy(AI->getType()->getContext());
+ if (AI->getType() == Int8PtrTy)
+ return isUsedByLifetimeMarker(AI);
+
+ // Do a scan to find all the bitcasts to i8*.
+ for (Value::use_iterator I = AI->use_begin(), E = AI->use_end(); I != E;
+ ++I) {
+ if (I->getType() != Int8PtrTy) continue;
+ if (!isa<BitCastInst>(*I)) continue;
+ if (isUsedByLifetimeMarker(*I))
+ return true;
+ }
+ return false;
+}
+
// InlineFunction - This function inlines the called function into the basic
// block of the caller. This returns false if it is not possible to inline this
// call. The program is still in a well defined state if this occurs though.
@@ -460,6 +891,26 @@ bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
}
}
+ // Leave lifetime markers for the static alloca's, scoping them to the
+ // function we just inlined.
+ if (!IFI.StaticAllocas.empty()) {
+ IRBuilder<> builder(FirstNewBlock->begin());
+ for (unsigned ai = 0, ae = IFI.StaticAllocas.size(); ai != ae; ++ai) {
+ AllocaInst *AI = IFI.StaticAllocas[ai];
+
+ // If the alloca is already scoped to something smaller than the whole
+ // function then there's no need to add redundant, less accurate markers.
+ if (hasLifetimeMarkers(AI))
+ continue;
+
+ builder.CreateLifetimeStart(AI);
+ for (unsigned ri = 0, re = Returns.size(); ri != re; ++ri) {
+ IRBuilder<> builder(Returns[ri]);
+ builder.CreateLifetimeEnd(AI);
+ }
+ }
+ }
+
// If the inlined code contained dynamic alloca instructions, wrap the inlined
// code with llvm.stacksave/llvm.stackrestore intrinsics.
if (InlinedFunctionInfo.ContainsDynamicAllocas) {
@@ -468,25 +919,14 @@ bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
Function *StackSave = Intrinsic::getDeclaration(M, Intrinsic::stacksave);
Function *StackRestore=Intrinsic::getDeclaration(M,Intrinsic::stackrestore);
- // If we are preserving the callgraph, add edges to the stacksave/restore
- // functions for the calls we insert.
- CallGraphNode *StackSaveCGN = 0, *StackRestoreCGN = 0, *CallerNode = 0;
- if (CallGraph *CG = IFI.CG) {
- StackSaveCGN = CG->getOrInsertFunction(StackSave);
- StackRestoreCGN = CG->getOrInsertFunction(StackRestore);
- CallerNode = (*CG)[Caller];
- }
-
// Insert the llvm.stacksave.
CallInst *SavedPtr = CallInst::Create(StackSave, "savedstack",
FirstNewBlock->begin());
- if (IFI.CG) CallerNode->addCalledFunction(SavedPtr, StackSaveCGN);
// Insert a call to llvm.stackrestore before any return instructions in the
// inlined function.
for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
- CallInst *CI = CallInst::Create(StackRestore, SavedPtr, "", Returns[i]);
- if (IFI.CG) CallerNode->addCalledFunction(CI, StackRestoreCGN);
+ CallInst::Create(StackRestore, SavedPtr, "", Returns[i]);
}
// Count the number of StackRestore calls we insert.
@@ -498,8 +938,7 @@ bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
for (Function::iterator BB = FirstNewBlock, E = Caller->end();
BB != E; ++BB)
if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
- CallInst *CI = CallInst::Create(StackRestore, SavedPtr, "", UI);
- if (IFI.CG) CallerNode->addCalledFunction(CI, StackRestoreCGN);
+ CallInst::Create(StackRestore, SavedPtr, "", UI);
++NumStackRestores;
}
}
diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index 4bca2fc..3bdbaa5 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -20,6 +20,7 @@
#include "llvm/Instructions.h"
#include "llvm/Intrinsics.h"
#include "llvm/IntrinsicInst.h"
+#include "llvm/Metadata.h"
#include "llvm/Operator.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
@@ -34,6 +35,7 @@
#include "llvm/Support/CFG.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/Support/IRBuilder.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/ValueHandle.h"
#include "llvm/Support/raw_ostream.h"
@@ -43,12 +45,16 @@ using namespace llvm;
// Local constant propagation.
//
-// ConstantFoldTerminator - If a terminator instruction is predicated on a
-// constant value, convert it into an unconditional branch to the constant
-// destination.
-//
-bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
+/// ConstantFoldTerminator - If a terminator instruction is predicated on a
+/// constant value, convert it into an unconditional branch to the constant
+/// destination. This is a nontrivial operation because the successors of this
+/// basic block must have their PHI nodes updated.
+/// Also calls RecursivelyDeleteTriviallyDeadInstructions() on any branch/switch
+/// conditions and indirectbr addresses this might make dead if
+/// DeleteDeadConditions is true.
+bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions) {
TerminatorInst *T = BB->getTerminator();
+ IRBuilder<> Builder(T);
// Branch - See if we are conditional jumping on constant
if (BranchInst *BI = dyn_cast<BranchInst>(T)) {
@@ -71,7 +77,7 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
OldDest->removePredecessor(BB);
// Replace the conditional branch with an unconditional one.
- BranchInst::Create(Destination, BI);
+ Builder.CreateBr(Destination);
BI->eraseFromParent();
return true;
}
@@ -86,8 +92,11 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
Dest1->removePredecessor(BI->getParent());
// Replace the conditional branch with an unconditional one.
- BranchInst::Create(Dest1, BI);
+ Builder.CreateBr(Dest1);
+ Value *Cond = BI->getCondition();
BI->eraseFromParent();
+ if (DeleteDeadConditions)
+ RecursivelyDeleteTriviallyDeadInstructions(Cond);
return true;
}
return false;
@@ -136,7 +145,7 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
// now.
if (TheOnlyDest) {
// Insert the new branch.
- BranchInst::Create(TheOnlyDest, SI);
+ Builder.CreateBr(TheOnlyDest);
BasicBlock *BB = SI->getParent();
// Remove entries from PHI nodes which we no longer branch to...
@@ -150,17 +159,21 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
}
// Delete the old switch.
- BB->getInstList().erase(SI);
+ Value *Cond = SI->getCondition();
+ SI->eraseFromParent();
+ if (DeleteDeadConditions)
+ RecursivelyDeleteTriviallyDeadInstructions(Cond);
return true;
}
if (SI->getNumSuccessors() == 2) {
// Otherwise, we can fold this switch into a conditional branch
// instruction if it has only one non-default destination.
- Value *Cond = new ICmpInst(SI, ICmpInst::ICMP_EQ, SI->getCondition(),
- SI->getSuccessorValue(1), "cond");
+ Value *Cond = Builder.CreateICmpEQ(SI->getCondition(),
+ SI->getSuccessorValue(1), "cond");
+
// Insert the new branch.
- BranchInst::Create(SI->getSuccessor(1), SI->getSuccessor(0), Cond, SI);
+ Builder.CreateCondBr(Cond, SI->getSuccessor(1), SI->getSuccessor(0));
// Delete the old switch.
SI->eraseFromParent();
@@ -175,7 +188,7 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
dyn_cast<BlockAddress>(IBI->getAddress()->stripPointerCasts())) {
BasicBlock *TheOnlyDest = BA->getBasicBlock();
// Insert the new branch.
- BranchInst::Create(TheOnlyDest, IBI);
+ Builder.CreateBr(TheOnlyDest);
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
if (IBI->getDestination(i) == TheOnlyDest)
@@ -183,7 +196,10 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
else
IBI->getDestination(i)->removePredecessor(IBI->getParent());
}
+ Value *Address = IBI->getAddress();
IBI->eraseFromParent();
+ if (DeleteDeadConditions)
+ RecursivelyDeleteTriviallyDeadInstructions(Address);
// If we didn't find our destination in the IBI successor list, then we
// have undefined behavior. Replace the unconditional branch with an
@@ -785,10 +801,19 @@ bool llvm::ConvertDebugDeclareToDebugValue(DbgDeclareInst *DDI,
if (!DIVar.Verify())
return false;
- Instruction *DbgVal =
- Builder.insertDbgValueIntrinsic(SI->getOperand(0), 0,
- DIVar, SI);
-
+ Instruction *DbgVal = NULL;
+ // If an argument is zero extended then use argument directly. The ZExt
+ // may be zapped by an optimization pass in future.
+ Argument *ExtendedArg = NULL;
+ if (ZExtInst *ZExt = dyn_cast<ZExtInst>(SI->getOperand(0)))
+ ExtendedArg = dyn_cast<Argument>(ZExt->getOperand(0));
+ if (SExtInst *SExt = dyn_cast<SExtInst>(SI->getOperand(0)))
+ ExtendedArg = dyn_cast<Argument>(SExt->getOperand(0));
+ if (ExtendedArg)
+ DbgVal = Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar, SI);
+ else
+ DbgVal = Builder.insertDbgValueIntrinsic(SI->getOperand(0), 0, DIVar, SI);
+
// Propagate any debug metadata from the store onto the dbg.value.
DebugLoc SIDL = SI->getDebugLoc();
if (!SIDL.isUnknown())
@@ -853,3 +878,15 @@ bool llvm::LowerDbgDeclare(Function &F) {
}
return true;
}
+
+/// FindAllocaDbgDeclare - Finds the llvm.dbg.declare intrinsic describing the
+/// alloca 'V', if any.
+DbgDeclareInst *llvm::FindAllocaDbgDeclare(Value *V) {
+ if (MDNode *DebugNode = MDNode::getIfExists(V->getContext(), V))
+ for (Value::use_iterator UI = DebugNode->use_begin(),
+ E = DebugNode->use_end(); UI != E; ++UI)
+ if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(*UI))
+ return DDI;
+
+ return 0;
+}
diff --git a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
index 50c9ae2..a1736b9 100644
--- a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
+++ b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
@@ -100,18 +100,6 @@ bool llvm::isAllocaPromotable(const AllocaInst *AI) {
return true;
}
-/// FindAllocaDbgDeclare - Finds the llvm.dbg.declare intrinsic describing the
-/// alloca 'V', if any.
-static DbgDeclareInst *FindAllocaDbgDeclare(Value *V) {
- if (MDNode *DebugNode = MDNode::getIfExists(V->getContext(), V))
- for (Value::use_iterator UI = DebugNode->use_begin(),
- E = DebugNode->use_end(); UI != E; ++UI)
- if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(*UI))
- return DDI;
-
- return 0;
-}
-
namespace {
struct AllocaInfo;
diff --git a/lib/Transforms/Utils/SSAUpdater.cpp b/lib/Transforms/Utils/SSAUpdater.cpp
index 2860c3e..b336194 100644
--- a/lib/Transforms/Utils/SSAUpdater.cpp
+++ b/lib/Transforms/Utils/SSAUpdater.cpp
@@ -14,7 +14,9 @@
#define DEBUG_TYPE "ssaupdater"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
#include "llvm/ADT/DenseMap.h"
+#include "llvm/Analysis/DIBuilder.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Support/AlignOf.h"
#include "llvm/Support/Allocator.h"
@@ -22,6 +24,7 @@
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SSAUpdater.h"
#include "llvm/Transforms/Utils/SSAUpdaterImpl.h"
@@ -355,7 +358,8 @@ Value *SSAUpdater::GetValueAtEndOfBlockInternal(BasicBlock *BB) {
LoadAndStorePromoter::
LoadAndStorePromoter(const SmallVectorImpl<Instruction*> &Insts,
- SSAUpdater &S, StringRef BaseName) : SSA(S) {
+ SSAUpdater &S, DbgDeclareInst *DD, DIBuilder *DB,
+ StringRef BaseName) : SSA(S), DDI(DD), DIB(DB) {
if (Insts.empty()) return;
Value *SomeVal;
@@ -402,9 +406,11 @@ run(const SmallVectorImpl<Instruction*> &Insts) const {
// single user in it, we can rewrite it trivially.
if (BlockUses.size() == 1) {
// If it is a store, it is a trivial def of the value in the block.
- if (StoreInst *SI = dyn_cast<StoreInst>(User))
+ if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
+ if (DDI)
+ ConvertDebugDeclareToDebugValue(DDI, SI, *DIB);
SSA.AddAvailableValue(BB, SI->getOperand(0));
- else
+ } else
// Otherwise it is a load, queue it to rewrite as a live-in load.
LiveInLoads.push_back(cast<LoadInst>(User));
BlockUses.clear();
@@ -453,12 +459,15 @@ run(const SmallVectorImpl<Instruction*> &Insts) const {
continue;
}
- if (StoreInst *S = dyn_cast<StoreInst>(II)) {
+ if (StoreInst *SI = dyn_cast<StoreInst>(II)) {
// If this is a store to an unrelated pointer, ignore it.
- if (!isInstInList(S, Insts)) continue;
-
+ if (!isInstInList(SI, Insts)) continue;
+
+ if (DDI)
+ ConvertDebugDeclareToDebugValue(DDI, SI, *DIB);
+
// Remember that this is the active value in the block.
- StoredValue = S->getOperand(0);
+ StoredValue = SI->getOperand(0);
}
}
@@ -513,4 +522,7 @@ run(const SmallVectorImpl<Instruction*> &Insts) const {
instructionDeleted(User);
User->eraseFromParent();
}
+
+ if (DDI)
+ DDI->eraseFromParent();
}
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 18b8573..6df846c 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -20,6 +20,7 @@
#include "llvm/DerivedTypes.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/ADT/DenseMap.h"
@@ -31,6 +32,8 @@
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ConstantRange.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/IRBuilder.h"
+#include "llvm/Support/NoFolder.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <set>
@@ -55,16 +58,18 @@ class SimplifyCFGOpt {
BasicBlock *GetValueEqualityComparisonCases(TerminatorInst *TI,
std::vector<std::pair<ConstantInt*, BasicBlock*> > &Cases);
bool SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
- BasicBlock *Pred);
- bool FoldValueComparisonIntoPredecessors(TerminatorInst *TI);
+ BasicBlock *Pred,
+ IRBuilder<> &Builder);
+ bool FoldValueComparisonIntoPredecessors(TerminatorInst *TI,
+ IRBuilder<> &Builder);
- bool SimplifyReturn(ReturnInst *RI);
- bool SimplifyUnwind(UnwindInst *UI);
+ bool SimplifyReturn(ReturnInst *RI, IRBuilder<> &Builder);
+ bool SimplifyUnwind(UnwindInst *UI, IRBuilder<> &Builder);
bool SimplifyUnreachable(UnreachableInst *UI);
- bool SimplifySwitch(SwitchInst *SI);
+ bool SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder);
bool SimplifyIndirectBr(IndirectBrInst *IBI);
- bool SimplifyUncondBranch(BranchInst *BI);
- bool SimplifyCondBranch(BranchInst *BI);
+ bool SimplifyUncondBranch(BranchInst *BI, IRBuilder <> &Builder);
+ bool SimplifyCondBranch(BranchInst *BI, IRBuilder <>&Builder);
public:
explicit SimplifyCFGOpt(const TargetData *td) : TD(td) {}
@@ -541,7 +546,8 @@ ValuesOverlap(std::vector<std::pair<ConstantInt*, BasicBlock*> > &C1,
/// form of jump threading.
bool SimplifyCFGOpt::
SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
- BasicBlock *Pred) {
+ BasicBlock *Pred,
+ IRBuilder<> &Builder) {
Value *PredVal = isValueEqualityComparison(Pred->getTerminator());
if (!PredVal) return false; // Not a value comparison in predecessor.
@@ -574,7 +580,7 @@ SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
// uncond br.
assert(ThisCases.size() == 1 && "Branch can only have one case!");
// Insert the new branch.
- Instruction *NI = BranchInst::Create(ThisDef, TI);
+ Instruction *NI = Builder.CreateBr(ThisDef);
(void) NI;
// Remove PHI node entries for the dead edge.
@@ -639,7 +645,7 @@ SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
CheckEdge = 0;
// Insert the new branch.
- Instruction *NI = BranchInst::Create(TheRealDest, TI);
+ Instruction *NI = Builder.CreateBr(TheRealDest);
(void) NI;
DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()
@@ -674,7 +680,8 @@ static int ConstantIntSortPredicate(const void *P1, const void *P2) {
/// equality comparison instruction (either a switch or a branch on "X == c").
/// See if any of the predecessors of the terminator block are value comparisons
/// on the same value. If so, and if safe to do so, fold them together.
-bool SimplifyCFGOpt::FoldValueComparisonIntoPredecessors(TerminatorInst *TI) {
+bool SimplifyCFGOpt::FoldValueComparisonIntoPredecessors(TerminatorInst *TI,
+ IRBuilder<> &Builder) {
BasicBlock *BB = TI->getParent();
Value *CV = isValueEqualityComparison(TI); // CondVal
assert(CV && "Not a comparison?");
@@ -767,16 +774,18 @@ bool SimplifyCFGOpt::FoldValueComparisonIntoPredecessors(TerminatorInst *TI) {
for (unsigned i = 0, e = NewSuccessors.size(); i != e; ++i)
AddPredecessorToBlock(NewSuccessors[i], Pred, BB);
+ Builder.SetInsertPoint(PTI);
// Convert pointer to int before we switch.
if (CV->getType()->isPointerTy()) {
assert(TD && "Cannot switch on pointer without TargetData");
- CV = new PtrToIntInst(CV, TD->getIntPtrType(CV->getContext()),
- "magicptr", PTI);
+ CV = Builder.CreatePtrToInt(CV, TD->getIntPtrType(CV->getContext()),
+ "magicptr");
}
// Now that the successors are updated, create the new Switch instruction.
- SwitchInst *NewSI = SwitchInst::Create(CV, PredDefault,
- PredCases.size(), PTI);
+ SwitchInst *NewSI = Builder.CreateSwitch(CV, PredDefault,
+ PredCases.size());
+ NewSI->setDebugLoc(PTI->getDebugLoc());
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
NewSI->addCase(PredCases[i].first, PredCases[i].second);
@@ -900,6 +909,7 @@ HoistTerminator:
NT->takeName(I1);
}
+ IRBuilder<true, NoFolder> Builder(NT);
// Hoisting one of the terminators from our successor is a great thing.
// Unfortunately, the successors of the if/else blocks may have PHI nodes in
// them. If they do, all PHI entries for BB1/BB2 must agree for all PHI
@@ -916,9 +926,11 @@ HoistTerminator:
// These values do not agree. Insert a select instruction before NT
// that determines the right value.
SelectInst *&SI = InsertedSelects[std::make_pair(BB1V, BB2V)];
- if (SI == 0)
- SI = SelectInst::Create(BI->getCondition(), BB1V, BB2V,
- BB1V->getName()+"."+BB2V->getName(), NT);
+ if (SI == 0)
+ SI = cast<SelectInst>
+ (Builder.CreateSelect(BI->getCondition(), BB1V, BB2V,
+ BB1V->getName()+"."+BB2V->getName()));
+
// Make the PHI node use the select for all incoming values for BB1/BB2
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (PN->getIncomingBlock(i) == BB1 || PN->getIncomingBlock(i) == BB2)
@@ -1076,13 +1088,16 @@ static bool SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *BB1) {
// Create a select whose true value is the speculatively executed value and
// false value is the previously determined FalseV.
+ IRBuilder<true, NoFolder> Builder(BI);
SelectInst *SI;
if (Invert)
- SI = SelectInst::Create(BrCond, FalseV, HInst,
- FalseV->getName() + "." + HInst->getName(), BI);
+ SI = cast<SelectInst>
+ (Builder.CreateSelect(BrCond, FalseV, HInst,
+ FalseV->getName() + "." + HInst->getName()));
else
- SI = SelectInst::Create(BrCond, HInst, FalseV,
- HInst->getName() + "." + FalseV->getName(), BI);
+ SI = cast<SelectInst>
+ (Builder.CreateSelect(BrCond, HInst, FalseV,
+ HInst->getName() + "." + FalseV->getName()));
// Make the PHI node use the select for all incoming values for "then" and
// "if" blocks.
@@ -1156,6 +1171,8 @@ static bool FoldCondBranchOnPHI(BranchInst *BI, const TargetData *TD) {
BasicBlock *RealDest = BI->getSuccessor(!CB->getZExtValue());
if (RealDest == BB) continue; // Skip self loops.
+ // Skip if the predecessor's terminator is an indirect branch.
+ if (isa<IndirectBrInst>(PredBB->getTerminator())) continue;
// The dest block might have PHI nodes, other predecessors and other
// difficult cases. Instead of being smart about this, just insert a new
@@ -1211,7 +1228,7 @@ static bool FoldCondBranchOnPHI(BranchInst *BI, const TargetData *TD) {
BB->removePredecessor(PredBB);
PredBBTI->setSuccessor(i, EdgeBB);
}
-
+
// Recurse, simplifying any other constants.
return FoldCondBranchOnPHI(BI, TD) | true;
}
@@ -1320,6 +1337,7 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetData *TD) {
// If we can still promote the PHI nodes after this gauntlet of tests,
// do all of the PHI's now.
Instruction *InsertPt = DomBlock->getTerminator();
+ IRBuilder<true, NoFolder> Builder(InsertPt);
// Move all 'aggressive' instructions, which are defined in the
// conditional parts of the if's up to the dominating block.
@@ -1337,7 +1355,8 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetData *TD) {
Value *TrueVal = PN->getIncomingValue(PN->getIncomingBlock(0) == IfFalse);
Value *FalseVal = PN->getIncomingValue(PN->getIncomingBlock(0) == IfTrue);
- Value *NV = SelectInst::Create(IfCond, TrueVal, FalseVal, "", InsertPt);
+ SelectInst *NV =
+ cast<SelectInst>(Builder.CreateSelect(IfCond, TrueVal, FalseVal, ""));
PN->replaceAllUsesWith(NV);
NV->takeName(PN);
PN->eraseFromParent();
@@ -1347,7 +1366,8 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetData *TD) {
// has been flattened. Change DomBlock to jump directly to our new block to
// avoid other simplifycfg's kicking in on the diamond.
TerminatorInst *OldTI = DomBlock->getTerminator();
- BranchInst::Create(BB, OldTI);
+ Builder.SetInsertPoint(OldTI);
+ Builder.CreateBr(BB);
OldTI->eraseFromParent();
return true;
}
@@ -1355,7 +1375,8 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetData *TD) {
/// SimplifyCondBranchToTwoReturns - If we found a conditional branch that goes
/// to two returning blocks, try to merge them together into one return,
/// introducing a select if the return values disagree.
-static bool SimplifyCondBranchToTwoReturns(BranchInst *BI) {
+static bool SimplifyCondBranchToTwoReturns(BranchInst *BI,
+ IRBuilder<> &Builder) {
assert(BI->isConditional() && "Must be a conditional branch");
BasicBlock *TrueSucc = BI->getSuccessor(0);
BasicBlock *FalseSucc = BI->getSuccessor(1);
@@ -1370,13 +1391,14 @@ static bool SimplifyCondBranchToTwoReturns(BranchInst *BI) {
if (!FalseSucc->getFirstNonPHIOrDbg()->isTerminator())
return false;
+ Builder.SetInsertPoint(BI);
// Okay, we found a branch that is going to two return nodes. If
// there is no return value for this function, just change the
// branch into a return.
if (FalseRet->getNumOperands() == 0) {
TrueSucc->removePredecessor(BI->getParent());
FalseSucc->removePredecessor(BI->getParent());
- ReturnInst::Create(BI->getContext(), 0, BI);
+ Builder.CreateRetVoid();
EraseTerminatorInstAndDCECond(BI);
return true;
}
@@ -1419,14 +1441,14 @@ static bool SimplifyCondBranchToTwoReturns(BranchInst *BI) {
} else if (isa<UndefValue>(TrueValue)) {
TrueValue = FalseValue;
} else {
- TrueValue = SelectInst::Create(BrCond, TrueValue,
- FalseValue, "retval", BI);
+ TrueValue = Builder.CreateSelect(BrCond, TrueValue,
+ FalseValue, "retval");
}
}
- Value *RI = !TrueValue ?
- ReturnInst::Create(BI->getContext(), BI) :
- ReturnInst::Create(BI->getContext(), TrueValue, BI);
+ Value *RI = !TrueValue ?
+ Builder.CreateRetVoid() : Builder.CreateRet(TrueValue);
+
(void) RI;
DEBUG(dbgs() << "\nCHANGING BRANCH TO TWO RETURNS INTO SELECT:"
@@ -1443,6 +1465,7 @@ static bool SimplifyCondBranchToTwoReturns(BranchInst *BI) {
/// the predecessor and use logical operations to pick the right destination.
bool llvm::FoldBranchToCommonDest(BranchInst *BI) {
BasicBlock *BB = BI->getParent();
+
Instruction *Cond = dyn_cast<Instruction>(BI->getCondition());
if (Cond == 0 || (!isa<CmpInst>(Cond) && !isa<BinaryOperator>(Cond)) ||
Cond->getParent() != BB || !Cond->hasOneUse())
@@ -1563,7 +1586,8 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI) {
}
DEBUG(dbgs() << "FOLDING BRANCH TO COMMON DEST:\n" << *PBI << *BB);
-
+ IRBuilder<> Builder(PBI);
+
// If we need to invert the condition in the pred block to match, do so now.
if (InvertPredCond) {
Value *NewCond = PBI->getCondition();
@@ -1572,8 +1596,8 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI) {
CmpInst *CI = cast<CmpInst>(NewCond);
CI->setPredicate(CI->getInversePredicate());
} else {
- NewCond = BinaryOperator::CreateNot(NewCond,
- PBI->getCondition()->getName()+".not", PBI);
+ NewCond = Builder.CreateNot(NewCond,
+ PBI->getCondition()->getName()+".not");
}
PBI->setCondition(NewCond);
@@ -1600,8 +1624,9 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI) {
New->takeName(Cond);
Cond->setName(New->getName()+".old");
- Value *NewCond = BinaryOperator::Create(Opc, PBI->getCondition(),
- New, "or.cond", PBI);
+ Instruction *NewCond =
+ cast<Instruction>(Builder.CreateBinOp(Opc, PBI->getCondition(),
+ New, "or.cond"));
PBI->setCondition(NewCond);
if (PBI->getSuccessor(0) == BB) {
AddPredecessorToBlock(TrueDest, PredBlock, BB);
@@ -1744,23 +1769,22 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI) {
}
DEBUG(dbgs() << *PBI->getParent()->getParent());
-
+
// BI may have other predecessors. Because of this, we leave
// it alone, but modify PBI.
// Make sure we get to CommonDest on True&True directions.
Value *PBICond = PBI->getCondition();
+ IRBuilder<true, NoFolder> Builder(PBI);
if (PBIOp)
- PBICond = BinaryOperator::CreateNot(PBICond,
- PBICond->getName()+".not",
- PBI);
+ PBICond = Builder.CreateNot(PBICond, PBICond->getName()+".not");
+
Value *BICond = BI->getCondition();
if (BIOp)
- BICond = BinaryOperator::CreateNot(BICond,
- BICond->getName()+".not",
- PBI);
+ BICond = Builder.CreateNot(BICond, BICond->getName()+".not");
+
// Merge the conditions.
- Value *Cond = BinaryOperator::CreateOr(PBICond, BICond, "brmerge", PBI);
+ Value *Cond = Builder.CreateOr(PBICond, BICond, "brmerge");
// Modify PBI to branch on the new condition to the new dests.
PBI->setCondition(Cond);
@@ -1783,8 +1807,8 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI) {
Value *PBIV = PN->getIncomingValue(PBBIdx);
if (BIV != PBIV) {
// Insert a select in PBI to pick the right value.
- Value *NV = SelectInst::Create(PBICond, PBIV, BIV,
- PBIV->getName()+".mux", PBI);
+ Value *NV = cast<SelectInst>
+ (Builder.CreateSelect(PBICond, PBIV, BIV, PBIV->getName()+".mux"));
PN->setIncomingValue(PBBIdx, NV);
}
}
@@ -1823,16 +1847,19 @@ static bool SimplifyTerminatorOnSelect(TerminatorInst *OldTerm, Value *Cond,
Succ->removePredecessor(OldTerm->getParent());
}
+ IRBuilder<> Builder(OldTerm);
+ Builder.SetCurrentDebugLocation(OldTerm->getDebugLoc());
+
// Insert an appropriate new terminator.
if ((KeepEdge1 == 0) && (KeepEdge2 == 0)) {
if (TrueBB == FalseBB)
// We were only looking for one successor, and it was present.
// Create an unconditional branch to it.
- BranchInst::Create(TrueBB, OldTerm);
+ Builder.CreateBr(TrueBB);
else
// We found both of the successors we were looking for.
// Create a conditional branch sharing the condition of the select.
- BranchInst::Create(TrueBB, FalseBB, Cond, OldTerm);
+ Builder.CreateCondBr(Cond, TrueBB, FalseBB);
} else if (KeepEdge1 && (KeepEdge2 || TrueBB == FalseBB)) {
// Neither of the selected blocks were successors, so this
// terminator must be unreachable.
@@ -1843,10 +1870,10 @@ static bool SimplifyTerminatorOnSelect(TerminatorInst *OldTerm, Value *Cond,
// the edge to the one that wasn't must be unreachable.
if (KeepEdge1 == 0)
// Only TrueBB was found.
- BranchInst::Create(TrueBB, OldTerm);
+ Builder.CreateBr(TrueBB);
else
// Only FalseBB was found.
- BranchInst::Create(FalseBB, OldTerm);
+ Builder.CreateBr(FalseBB);
}
EraseTerminatorInstAndDCECond(OldTerm);
@@ -1911,8 +1938,10 @@ static bool SimplifyIndirectBrOnSelect(IndirectBrInst *IBI, SelectInst *SI) {
/// We prefer to split the edge to 'end' so that there is a true/false entry to
/// the PHI, merging the third icmp into the switch.
static bool TryToSimplifyUncondBranchWithICmpInIt(ICmpInst *ICI,
- const TargetData *TD) {
+ const TargetData *TD,
+ IRBuilder<> &Builder) {
BasicBlock *BB = ICI->getParent();
+
// If the block has any PHIs in it or the icmp has multiple uses, it is too
// complex.
if (isa<PHINode>(BB->begin()) || !ICI->hasOneUse()) return false;
@@ -1990,7 +2019,9 @@ static bool TryToSimplifyUncondBranchWithICmpInIt(ICmpInst *ICI,
SI->addCase(Cst, NewBB);
// NewBB branches to the phi block, add the uncond branch and the phi entry.
- BranchInst::Create(SuccBlock, NewBB);
+ Builder.SetInsertPoint(NewBB);
+ Builder.SetCurrentDebugLocation(SI->getDebugLoc());
+ Builder.CreateBr(SuccBlock);
PHIUse->addIncoming(NewCst, NewBB);
return true;
}
@@ -1998,7 +2029,8 @@ static bool TryToSimplifyUncondBranchWithICmpInIt(ICmpInst *ICI,
/// SimplifyBranchOnICmpChain - The specified branch is a conditional branch.
/// Check to see if it is branching on an or/and chain of icmp instructions, and
/// fold it into a switch instruction if so.
-static bool SimplifyBranchOnICmpChain(BranchInst *BI, const TargetData *TD) {
+static bool SimplifyBranchOnICmpChain(BranchInst *BI, const TargetData *TD,
+ IRBuilder<> &Builder) {
Instruction *Cond = dyn_cast<Instruction>(BI->getCondition());
if (Cond == 0) return false;
@@ -2054,11 +2086,12 @@ static bool SimplifyBranchOnICmpChain(BranchInst *BI, const TargetData *TD) {
BasicBlock *NewBB = BB->splitBasicBlock(BI, "switch.early.test");
// Remove the uncond branch added to the old block.
TerminatorInst *OldTI = BB->getTerminator();
-
+ Builder.SetInsertPoint(OldTI);
+
if (TrueWhenEqual)
- BranchInst::Create(EdgeBB, NewBB, ExtraCase, OldTI);
+ Builder.CreateCondBr(ExtraCase, EdgeBB, NewBB);
else
- BranchInst::Create(NewBB, EdgeBB, ExtraCase, OldTI);
+ Builder.CreateCondBr(ExtraCase, NewBB, EdgeBB);
OldTI->eraseFromParent();
@@ -2070,18 +2103,19 @@ static bool SimplifyBranchOnICmpChain(BranchInst *BI, const TargetData *TD) {
<< "\nEXTRABB = " << *BB);
BB = NewBB;
}
-
+
+ Builder.SetInsertPoint(BI);
// Convert pointer to int before we switch.
if (CompVal->getType()->isPointerTy()) {
assert(TD && "Cannot switch on pointer without TargetData");
- CompVal = new PtrToIntInst(CompVal,
- TD->getIntPtrType(CompVal->getContext()),
- "magicptr", BI);
+ CompVal = Builder.CreatePtrToInt(CompVal,
+ TD->getIntPtrType(CompVal->getContext()),
+ "magicptr");
}
// Create the new switch instruction now.
- SwitchInst *New = SwitchInst::Create(CompVal, DefaultBB, Values.size(), BI);
-
+ SwitchInst *New = Builder.CreateSwitch(CompVal, DefaultBB, Values.size());
+
// Add all of the 'cases' to the switch instruction.
for (unsigned i = 0, e = Values.size(); i != e; ++i)
New->addCase(Values[i], EdgeBB);
@@ -2104,7 +2138,7 @@ static bool SimplifyBranchOnICmpChain(BranchInst *BI, const TargetData *TD) {
return true;
}
-bool SimplifyCFGOpt::SimplifyReturn(ReturnInst *RI) {
+bool SimplifyCFGOpt::SimplifyReturn(ReturnInst *RI, IRBuilder<> &Builder) {
BasicBlock *BB = RI->getParent();
if (!BB->getFirstNonPHIOrDbg()->isTerminator()) return false;
@@ -2148,13 +2182,13 @@ bool SimplifyCFGOpt::SimplifyReturn(ReturnInst *RI) {
// Check to see if the non-BB successor is also a return block.
if (isa<ReturnInst>(BI->getSuccessor(0)->getTerminator()) &&
isa<ReturnInst>(BI->getSuccessor(1)->getTerminator()) &&
- SimplifyCondBranchToTwoReturns(BI))
+ SimplifyCondBranchToTwoReturns(BI, Builder))
return true;
}
return false;
}
-bool SimplifyCFGOpt::SimplifyUnwind(UnwindInst *UI) {
+bool SimplifyCFGOpt::SimplifyUnwind(UnwindInst *UI, IRBuilder<> &Builder) {
// Check to see if the first instruction in this block is just an unwind.
// If so, replace any invoke instructions which use this as an exception
// destination with call instructions.
@@ -2169,14 +2203,16 @@ bool SimplifyCFGOpt::SimplifyUnwind(UnwindInst *UI) {
if (II && II->getUnwindDest() == BB) {
// Insert a new branch instruction before the invoke, because this
// is now a fall through.
- BranchInst *BI = BranchInst::Create(II->getNormalDest(), II);
+ Builder.SetInsertPoint(II);
+ BranchInst *BI = Builder.CreateBr(II->getNormalDest());
Pred->getInstList().remove(II); // Take out of symbol table
// Insert the call now.
SmallVector<Value*,8> Args(II->op_begin(), II->op_end()-3);
- CallInst *CI = CallInst::Create(II->getCalledValue(),
- Args.begin(), Args.end(),
- II->getName(), BI);
+ Builder.SetInsertPoint(BI);
+ CallInst *CI = Builder.CreateCall(II->getCalledValue(),
+ Args.begin(), Args.end(),
+ II->getName());
CI->setCallingConv(II->getCallingConv());
CI->setAttributes(II->getAttributes());
// If the invoke produced a value, the Call now does instead.
@@ -2235,7 +2271,7 @@ bool SimplifyCFGOpt::SimplifyUnreachable(UnreachableInst *UI) {
SmallVector<BasicBlock*, 8> Preds(pred_begin(BB), pred_end(BB));
for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
TerminatorInst *TI = Preds[i]->getTerminator();
-
+ IRBuilder<> Builder(TI);
if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
if (BI->isUnconditional()) {
if (BI->getSuccessor(0) == BB) {
@@ -2245,10 +2281,10 @@ bool SimplifyCFGOpt::SimplifyUnreachable(UnreachableInst *UI) {
}
} else {
if (BI->getSuccessor(0) == BB) {
- BranchInst::Create(BI->getSuccessor(1), BI);
+ Builder.CreateBr(BI->getSuccessor(1));
EraseTerminatorInstAndDCECond(BI);
} else if (BI->getSuccessor(1) == BB) {
- BranchInst::Create(BI->getSuccessor(0), BI);
+ Builder.CreateBr(BI->getSuccessor(0));
EraseTerminatorInstAndDCECond(BI);
Changed = true;
}
@@ -2312,14 +2348,15 @@ bool SimplifyCFGOpt::SimplifyUnreachable(UnreachableInst *UI) {
if (II->getUnwindDest() == BB) {
// Convert the invoke to a call instruction. This would be a good
// place to note that the call does not throw though.
- BranchInst *BI = BranchInst::Create(II->getNormalDest(), II);
+ BranchInst *BI = Builder.CreateBr(II->getNormalDest());
II->removeFromParent(); // Take out of symbol table
// Insert the call now...
SmallVector<Value*, 8> Args(II->op_begin(), II->op_end()-3);
- CallInst *CI = CallInst::Create(II->getCalledValue(),
- Args.begin(), Args.end(),
- II->getName(), BI);
+ Builder.SetInsertPoint(BI);
+ CallInst *CI = Builder.CreateCall(II->getCalledValue(),
+ Args.begin(), Args.end(),
+ II->getName());
CI->setCallingConv(II->getCallingConv());
CI->setAttributes(II->getAttributes());
// If the invoke produced a value, the call does now instead.
@@ -2343,7 +2380,7 @@ bool SimplifyCFGOpt::SimplifyUnreachable(UnreachableInst *UI) {
/// TurnSwitchRangeIntoICmp - Turns a switch with that contains only a
/// integer range comparison into a sub, an icmp and a branch.
-static bool TurnSwitchRangeIntoICmp(SwitchInst *SI) {
+static bool TurnSwitchRangeIntoICmp(SwitchInst *SI, IRBuilder<> &Builder) {
assert(SI->getNumCases() > 2 && "Degenerate switch?");
// Make sure all cases point to the same destination and gather the values.
@@ -2368,9 +2405,9 @@ static bool TurnSwitchRangeIntoICmp(SwitchInst *SI) {
Value *Sub = SI->getCondition();
if (!Offset->isNullValue())
- Sub = BinaryOperator::CreateAdd(Sub, Offset, Sub->getName()+".off", SI);
- Value *Cmp = new ICmpInst(SI, ICmpInst::ICMP_ULT, Sub, NumCases, "switch");
- BranchInst::Create(SI->getSuccessor(1), SI->getDefaultDest(), Cmp, SI);
+ Sub = Builder.CreateAdd(Sub, Offset, Sub->getName()+".off");
+ Value *Cmp = Builder.CreateICmpULT(Sub, NumCases, "switch");
+ Builder.CreateCondBr(Cmp, SI->getSuccessor(1), SI->getDefaultDest());
// Prune obsolete incoming values off the successor's PHI nodes.
for (BasicBlock::iterator BBI = SI->getSuccessor(1)->begin();
@@ -2383,7 +2420,37 @@ static bool TurnSwitchRangeIntoICmp(SwitchInst *SI) {
return true;
}
-bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI) {
+/// EliminateDeadSwitchCases - Compute masked bits for the condition of a switch
+/// and use it to remove dead cases.
+static bool EliminateDeadSwitchCases(SwitchInst *SI) {
+ Value *Cond = SI->getCondition();
+ unsigned Bits = cast<IntegerType>(Cond->getType())->getBitWidth();
+ APInt KnownZero(Bits, 0), KnownOne(Bits, 0);
+ ComputeMaskedBits(Cond, APInt::getAllOnesValue(Bits), KnownZero, KnownOne);
+
+ // Gather dead cases.
+ SmallVector<ConstantInt*, 8> DeadCases;
+ for (unsigned I = 1, E = SI->getNumCases(); I != E; ++I) {
+ if ((SI->getCaseValue(I)->getValue() & KnownZero) != 0 ||
+ (SI->getCaseValue(I)->getValue() & KnownOne) != KnownOne) {
+ DeadCases.push_back(SI->getCaseValue(I));
+ DEBUG(dbgs() << "SimplifyCFG: switch case '"
+ << SI->getCaseValue(I)->getValue() << "' is dead.\n");
+ }
+ }
+
+ // Remove dead cases from the switch.
+ for (unsigned I = 0, E = DeadCases.size(); I != E; ++I) {
+ unsigned Case = SI->findCaseValue(DeadCases[I]);
+ // Prune unused values from PHI nodes.
+ SI->getSuccessor(Case)->removePredecessor(SI->getParent());
+ SI->removeCase(Case);
+ }
+
+ return !DeadCases.empty();
+}
+
+bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) {
// If this switch is too complex to want to look at, ignore it.
if (!isValueEqualityComparison(SI))
return false;
@@ -2393,7 +2460,7 @@ bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI) {
// If we only have one predecessor, and if it is a branch on this value,
// see if that predecessor totally determines the outcome of this switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
- if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred))
+ if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
return SimplifyCFG(BB) | true;
Value *Cond = SI->getCondition();
@@ -2408,13 +2475,17 @@ bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI) {
while (isa<DbgInfoIntrinsic>(BBI))
++BBI;
if (SI == &*BBI)
- if (FoldValueComparisonIntoPredecessors(SI))
+ if (FoldValueComparisonIntoPredecessors(SI, Builder))
return SimplifyCFG(BB) | true;
// Try to transform the switch into an icmp and a branch.
- if (TurnSwitchRangeIntoICmp(SI))
+ if (TurnSwitchRangeIntoICmp(SI, Builder))
return SimplifyCFG(BB) | true;
-
+
+ // Remove unreachable cases.
+ if (EliminateDeadSwitchCases(SI))
+ return SimplifyCFG(BB) | true;
+
return false;
}
@@ -2455,7 +2526,7 @@ bool SimplifyCFGOpt::SimplifyIndirectBr(IndirectBrInst *IBI) {
return Changed;
}
-bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI) {
+bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI, IRBuilder<> &Builder){
BasicBlock *BB = BI->getParent();
// If the Terminator is the only non-phi instruction, simplify the block.
@@ -2470,7 +2541,8 @@ bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI) {
if (ICI->isEquality() && isa<ConstantInt>(ICI->getOperand(1))) {
for (++I; isa<DbgInfoIntrinsic>(I); ++I)
;
- if (I->isTerminator() && TryToSimplifyUncondBranchWithICmpInIt(ICI, TD))
+ if (I->isTerminator()
+ && TryToSimplifyUncondBranchWithICmpInIt(ICI, TD, Builder))
return true;
}
@@ -2478,7 +2550,7 @@ bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI) {
}
-bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI) {
+bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) {
BasicBlock *BB = BI->getParent();
// Conditional branch
@@ -2487,7 +2559,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI) {
// see if that predecessor totally determines the outcome of this
// switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
- if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred))
+ if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred, Builder))
return SimplifyCFG(BB) | true;
// This block must be empty, except for the setcond inst, if it exists.
@@ -2497,20 +2569,20 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI) {
while (isa<DbgInfoIntrinsic>(I))
++I;
if (&*I == BI) {
- if (FoldValueComparisonIntoPredecessors(BI))
+ if (FoldValueComparisonIntoPredecessors(BI, Builder))
return SimplifyCFG(BB) | true;
} else if (&*I == cast<Instruction>(BI->getCondition())){
++I;
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(I))
++I;
- if (&*I == BI && FoldValueComparisonIntoPredecessors(BI))
+ if (&*I == BI && FoldValueComparisonIntoPredecessors(BI, Builder))
return SimplifyCFG(BB) | true;
}
}
// Try to turn "br (X == 0 | X == 1), T, F" into a switch instruction.
- if (SimplifyBranchOnICmpChain(BI, TD))
+ if (SimplifyBranchOnICmpChain(BI, TD, Builder))
return true;
// We have a conditional branch to two blocks that are only reachable
@@ -2581,7 +2653,7 @@ bool SimplifyCFGOpt::run(BasicBlock *BB) {
// Check to see if we can constant propagate this terminator instruction
// away...
- Changed |= ConstantFoldTerminator(BB);
+ Changed |= ConstantFoldTerminator(BB, true);
// Check for and eliminate duplicate PHI nodes in this block.
Changed |= EliminateDuplicatePHINodes(BB);
@@ -2593,27 +2665,30 @@ bool SimplifyCFGOpt::run(BasicBlock *BB) {
if (MergeBlockIntoPredecessor(BB))
return true;
+ IRBuilder<> Builder(BB);
+
// If there is a trivial two-entry PHI node in this basic block, and we can
// eliminate it, do so now.
if (PHINode *PN = dyn_cast<PHINode>(BB->begin()))
if (PN->getNumIncomingValues() == 2)
Changed |= FoldTwoEntryPHINode(PN, TD);
+ Builder.SetInsertPoint(BB->getTerminator());
if (BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator())) {
if (BI->isUnconditional()) {
- if (SimplifyUncondBranch(BI)) return true;
+ if (SimplifyUncondBranch(BI, Builder)) return true;
} else {
- if (SimplifyCondBranch(BI)) return true;
+ if (SimplifyCondBranch(BI, Builder)) return true;
}
} else if (ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator())) {
- if (SimplifyReturn(RI)) return true;
+ if (SimplifyReturn(RI, Builder)) return true;
} else if (SwitchInst *SI = dyn_cast<SwitchInst>(BB->getTerminator())) {
- if (SimplifySwitch(SI)) return true;
+ if (SimplifySwitch(SI, Builder)) return true;
} else if (UnreachableInst *UI =
dyn_cast<UnreachableInst>(BB->getTerminator())) {
if (SimplifyUnreachable(UI)) return true;
} else if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
- if (SimplifyUnwind(UI)) return true;
+ if (SimplifyUnwind(UI, Builder)) return true;
} else if (IndirectBrInst *IBI =
dyn_cast<IndirectBrInst>(BB->getTerminator())) {
if (SimplifyIndirectBr(IBI)) return true;
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