// 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"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Module.h"
-#include "llvm/Instructions.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/Intrinsics.h"
-#include "llvm/Attributes.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CallGraph.h"
-#include "llvm/Analysis/DebugInfo.h"
+#include "llvm/Analysis/CaptureTracking.h"
#include "llvm/Analysis/InstructionSimplify.h"
-#include "llvm/Target/TargetData.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/IR/Attributes.h"
+#include "llvm/IR/CallSite.h"
+#include "llvm/IR/CFG.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfo.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/DIBuilder.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/StringExtras.h"
-#include "llvm/Support/CallSite.h"
-#include "llvm/Support/IRBuilder.h"
+#include "llvm/Support/CommandLine.h"
+#include <algorithm>
using namespace llvm;
-bool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI) {
- return InlineFunction(CallSite(CI), IFI);
-}
-bool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI) {
- return InlineFunction(CallSite(II), IFI);
-}
+static cl::opt<bool>
+EnableNoAliasConversion("enable-noalias-to-md-conversion", cl::init(true),
+ cl::Hidden,
+ cl::desc("Convert noalias attributes to metadata during inlining."));
-/// [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;
- }
+static cl::opt<bool>
+PreserveAlignmentAssumptions("preserve-alignment-assumptions-during-inlining",
+ cl::init(true), cl::Hidden,
+ cl::desc("Convert align attributes to assumptions during inlining."));
- return 0;
+bool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI,
+ bool InsertLifetime) {
+ return InlineFunction(CallSite(CI), IFI, InsertLifetime);
}
-
-/// [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;
+bool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI,
+ bool InsertLifetime) {
+ return InlineFunction(CallSite(II), IFI, InsertLifetime);
}
namespace {
/// A class for recording information about inlining through an invoke.
class InvokeInliningInfo {
- BasicBlock *OuterUnwindDest;
- EHSelectorInst *OuterSelector;
- BasicBlock *InnerUnwindDest;
- PHINode *InnerExceptionPHI;
- PHINode *InnerSelectorPHI;
+ BasicBlock *OuterResumeDest; ///< Destination of the invoke's unwind.
+ BasicBlock *InnerResumeDest; ///< Destination for the callee's resume.
+ LandingPadInst *CallerLPad; ///< LandingPadInst associated with the invoke.
+ PHINode *InnerEHValuesPHI; ///< PHI for EH values from landingpad insts.
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) {
+ InvokeInliningInfo(InvokeInst *II)
+ : OuterResumeDest(II->getUnwindDest()), InnerResumeDest(nullptr),
+ CallerLPad(nullptr), InnerEHValuesPHI(nullptr) {
+ // 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();
+ BasicBlock::iterator I = OuterResumeDest->begin();
+ for (; isa<PHINode>(I); ++I) {
// Save the value to use for this edge.
- PHINode *phi = cast<PHINode>(I);
- UnwindDestPHIValues.push_back(phi->getIncomingValueForBlock(invokeBB));
+ 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;
+ CallerLPad = cast<LandingPadInst>(I);
}
- EHSelectorInst *getOuterSelector() {
- if (!OuterSelector)
- OuterSelector = findSelectorForLandingPad(OuterUnwindDest);
- return OuterSelector;
+ /// getOuterResumeDest - The outer unwind destination is the target of
+ /// unwind edges introduced for calls within the inlined function.
+ BasicBlock *getOuterResumeDest() const {
+ return OuterResumeDest;
}
- BasicBlock *getInnerUnwindDest();
+ BasicBlock *getInnerResumeDest();
- bool forwardEHResume(CallInst *call, BasicBlock *src);
+ LandingPadInst *getLandingPadInst() const { return CallerLPad; }
- /// Add incoming-PHI values to the unwind destination block for
- /// the given basic block, using the values for the original
- /// invoke's source block.
+ /// forwardResume - Forward the 'resume' instruction to the caller's landing
+ /// pad block. When the landing pad block has only one predecessor, this is
+ /// a simple branch. When there is more than one predecessor, we need to
+ /// split the landing pad block after the landingpad instruction and jump
+ /// to there.
+ void forwardResume(ResumeInst *RI,
+ SmallPtrSetImpl<LandingPadInst*> &InlinedLPads);
+
+ /// addIncomingPHIValuesFor - 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);
+ addIncomingPHIValuesForInto(BB, OuterResumeDest);
}
void addIncomingPHIValuesForInto(BasicBlock *src, BasicBlock *dest) const {
};
}
-/// 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);
- }
+/// getInnerResumeDest - Get or create a target for the branch from ResumeInsts.
+BasicBlock *InvokeInliningInfo::getInnerResumeDest() {
+ if (InnerResumeDest) return InnerResumeDest;
// Split the landing pad.
- InnerUnwindDest = OuterUnwindDest->splitBasicBlock(splitPoint,
- OuterUnwindDest->getName() + ".body");
+ BasicBlock::iterator SplitPoint = CallerLPad; ++SplitPoint;
+ InnerResumeDest =
+ OuterResumeDest->splitBasicBlock(SplitPoint,
+ OuterResumeDest->getName() + ".body");
// The number of incoming edges we expect to the inner landing pad.
- const unsigned phiCapacity = 2;
+ 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();
+ // Create corresponding new PHIs for all the PHIs in the outer landing pad.
+ BasicBlock::iterator InsertPoint = InnerResumeDest->begin();
+ BasicBlock::iterator I = OuterResumeDest->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);
+ PHINode *OuterPHI = cast<PHINode>(I);
+ PHINode *InnerPHI = PHINode::Create(OuterPHI->getType(), PHICapacity,
+ OuterPHI->getName() + ".lpad-body",
+ InsertPoint);
+ OuterPHI->replaceAllUsesWith(InnerPHI);
+ InnerPHI->addIncoming(OuterPHI, OuterResumeDest);
}
- // 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);
+ // Create a PHI for the exception values.
+ InnerEHValuesPHI = PHINode::Create(CallerLPad->getType(), PHICapacity,
+ "eh.lpad-body", InsertPoint);
+ CallerLPad->replaceAllUsesWith(InnerEHValuesPHI);
+ InnerEHValuesPHI->addIncoming(CallerLPad, OuterResumeDest);
// All done.
- return InnerUnwindDest;
+ return InnerResumeDest;
}
-/// [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);
- }
+/// forwardResume - Forward the 'resume' instruction to the caller's landing pad
+/// block. When the landing pad block has only one predecessor, this is a simple
+/// branch. When there is more than one predecessor, we need to split the
+/// landing pad block after the landingpad instruction and jump to there.
+void InvokeInliningInfo::forwardResume(ResumeInst *RI,
+ SmallPtrSetImpl<LandingPadInst*> &InlinedLPads) {
+ BasicBlock *Dest = getInnerResumeDest();
+ BasicBlock *Src = RI->getParent();
- return true;
-}
+ BranchInst::Create(Dest, Src);
-/// [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());
+ // Update the PHIs in the destination. They were inserted in an order which
+ // makes this work.
+ addIncomingPHIValuesForInto(Src, Dest);
+
+ InnerEHValuesPHI->addIncoming(RI->getOperand(0), Src);
+ RI->eraseFromParent();
}
/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into
/// invokes. This function analyze BB to see if there are any calls, and if so,
/// 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.
-///
-/// Returns true to indicate that the next block should be skipped.
-static bool HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
+static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
InvokeInliningInfo &Invoke) {
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
Instruction *I = BBI++;
-
+
// We only need to check for function calls: inlined invoke
// 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 =
- IRBuilder<>(Inner).CreateCall(Inner->getCalledValue(), NewSelector);
- // 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())
+ // Inline asm calls cannot throw.
+ if (!CI || CI->doesNotThrow() || isa<InlineAsm>(CI->getCalledValue()))
continue;
-
- // Convert this function call into an invoke instruction.
- // First, split the basic block.
+
+ // Convert this function call into an invoke instruction. First, split the
+ // basic block.
BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");
// 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.
+ // 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,
- Invoke.getOuterUnwindDest(),
- InvokeArgs, CI->getName(), BB);
+ InvokeInst *II = InvokeInst::Create(CI->getCalledValue(), Split,
+ Invoke.getOuterResumeDest(),
+ InvokeArgs, CI->getName(), BB);
+ II->setDebugLoc(CI->getDebugLoc());
II->setCallingConv(CI->getCallingConv());
II->setAttributes(CI->getAttributes());
// updates the CallGraph if present, because it uses a WeakVH.
CI->replaceAllUsesWith(II);
- Split->getInstList().pop_front(); // Delete the original call
+ // Delete the original call
+ Split->getInstList().pop_front();
- // Update any PHI nodes in the exceptional block to indicate that
- // there is now a new entry in them.
+ // Update any PHI nodes in the exceptional block to indicate that there is
+ // now a new entry in them.
Invoke.addIncomingPHIValuesFor(BB);
- return false;
+ return;
}
-
- return false;
}
-
/// HandleInlinedInvoke - If we inlined an invoke site, we need to convert calls
-/// in the body of the inlined function into invokes and turn unwind
-/// instructions into branches to the invoke unwind dest.
+/// in the body of the inlined function into invokes.
///
/// II is the invoke instruction being inlined. FirstNewBlock is the first
/// block of the inlined code (the last block is the end of the function),
// The inlined code is currently at the end of the function, scan from the
// start of the inlined code to its end, checking for stuff we need to
- // rewrite. If the code doesn't have calls or unwinds, we know there is
- // nothing to rewrite.
- if (!InlinedCodeInfo.ContainsCalls && !InlinedCodeInfo.ContainsUnwinds) {
- // Now that everything is happy, we have one final detail. The PHI nodes in
- // the exception destination block still have entries due to the original
- // invoke instruction. Eliminate these entries (which might even delete the
- // PHI node) now.
- InvokeDest->removePredecessor(II->getParent());
- return;
+ // rewrite.
+ InvokeInliningInfo Invoke(II);
+
+ // Get all of the inlined landing pad instructions.
+ SmallPtrSet<LandingPadInst*, 16> InlinedLPads;
+ for (Function::iterator I = FirstNewBlock, E = Caller->end(); I != E; ++I)
+ if (InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator()))
+ InlinedLPads.insert(II->getLandingPadInst());
+
+ // Append the clauses from the outer landing pad instruction into the inlined
+ // landing pad instructions.
+ LandingPadInst *OuterLPad = Invoke.getLandingPadInst();
+ for (LandingPadInst *InlinedLPad : InlinedLPads) {
+ unsigned OuterNum = OuterLPad->getNumClauses();
+ InlinedLPad->reserveClauses(OuterNum);
+ for (unsigned OuterIdx = 0; OuterIdx != OuterNum; ++OuterIdx)
+ InlinedLPad->addClause(OuterLPad->getClause(OuterIdx));
+ if (OuterLPad->isCleanup())
+ InlinedLPad->setCleanup(true);
}
- InvokeInliningInfo Invoke(II);
-
for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){
if (InlinedCodeInfo.ContainsCalls)
- if (HandleCallsInBlockInlinedThroughInvoke(BB, Invoke)) {
- // Honor a request to skip the next block. We don't need to
- // consider UnwindInsts in this case either.
- ++BB;
+ HandleCallsInBlockInlinedThroughInvoke(BB, Invoke);
+
+ // Forward any resumes that are remaining here.
+ if (ResumeInst *RI = dyn_cast<ResumeInst>(BB->getTerminator()))
+ Invoke.forwardResume(RI, InlinedLPads);
+ }
+
+ // Now that everything is happy, we have one final detail. The PHI nodes in
+ // the exception destination block still have entries due to the original
+ // invoke instruction. Eliminate these entries (which might even delete the
+ // PHI node) now.
+ InvokeDest->removePredecessor(II->getParent());
+}
+
+/// CloneAliasScopeMetadata - When inlining a function that contains noalias
+/// scope metadata, this metadata needs to be cloned so that the inlined blocks
+/// have different "unqiue scopes" at every call site. Were this not done, then
+/// aliasing scopes from a function inlined into a caller multiple times could
+/// not be differentiated (and this would lead to miscompiles because the
+/// non-aliasing property communicated by the metadata could have
+/// call-site-specific control dependencies).
+static void CloneAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap) {
+ const Function *CalledFunc = CS.getCalledFunction();
+ SetVector<const MDNode *> MD;
+
+ // Note: We could only clone the metadata if it is already used in the
+ // caller. I'm omitting that check here because it might confuse
+ // inter-procedural alias analysis passes. We can revisit this if it becomes
+ // an efficiency or overhead problem.
+
+ for (Function::const_iterator I = CalledFunc->begin(), IE = CalledFunc->end();
+ I != IE; ++I)
+ for (BasicBlock::const_iterator J = I->begin(), JE = I->end(); J != JE; ++J) {
+ if (const MDNode *M = J->getMetadata(LLVMContext::MD_alias_scope))
+ MD.insert(M);
+ if (const MDNode *M = J->getMetadata(LLVMContext::MD_noalias))
+ MD.insert(M);
+ }
+
+ if (MD.empty())
+ return;
+
+ // Walk the existing metadata, adding the complete (perhaps cyclic) chain to
+ // the set.
+ SmallVector<const Metadata *, 16> Queue(MD.begin(), MD.end());
+ while (!Queue.empty()) {
+ const MDNode *M = cast<MDNode>(Queue.pop_back_val());
+ for (unsigned i = 0, ie = M->getNumOperands(); i != ie; ++i)
+ if (const MDNode *M1 = dyn_cast<MDNode>(M->getOperand(i)))
+ if (MD.insert(M1))
+ Queue.push_back(M1);
+ }
+
+ // Now we have a complete set of all metadata in the chains used to specify
+ // the noalias scopes and the lists of those scopes.
+ SmallVector<TempMDTuple, 16> DummyNodes;
+ DenseMap<const MDNode *, TrackingMDNodeRef> MDMap;
+ for (SetVector<const MDNode *>::iterator I = MD.begin(), IE = MD.end();
+ I != IE; ++I) {
+ DummyNodes.push_back(MDTuple::getTemporary(CalledFunc->getContext(), None));
+ MDMap[*I].reset(DummyNodes.back().get());
+ }
+
+ // Create new metadata nodes to replace the dummy nodes, replacing old
+ // metadata references with either a dummy node or an already-created new
+ // node.
+ for (SetVector<const MDNode *>::iterator I = MD.begin(), IE = MD.end();
+ I != IE; ++I) {
+ SmallVector<Metadata *, 4> NewOps;
+ for (unsigned i = 0, ie = (*I)->getNumOperands(); i != ie; ++i) {
+ const Metadata *V = (*I)->getOperand(i);
+ if (const MDNode *M = dyn_cast<MDNode>(V))
+ NewOps.push_back(MDMap[M]);
+ else
+ NewOps.push_back(const_cast<Metadata *>(V));
+ }
+
+ MDNode *NewM = MDNode::get(CalledFunc->getContext(), NewOps);
+ MDTuple *TempM = cast<MDTuple>(MDMap[*I]);
+ assert(TempM->isTemporary() && "Expected temporary node");
+
+ TempM->replaceAllUsesWith(NewM);
+ }
+
+ // Now replace the metadata in the new inlined instructions with the
+ // repacements from the map.
+ for (ValueToValueMapTy::iterator VMI = VMap.begin(), VMIE = VMap.end();
+ VMI != VMIE; ++VMI) {
+ if (!VMI->second)
+ continue;
+
+ Instruction *NI = dyn_cast<Instruction>(VMI->second);
+ if (!NI)
+ continue;
+
+ if (MDNode *M = NI->getMetadata(LLVMContext::MD_alias_scope)) {
+ MDNode *NewMD = MDMap[M];
+ // If the call site also had alias scope metadata (a list of scopes to
+ // which instructions inside it might belong), propagate those scopes to
+ // the inlined instructions.
+ if (MDNode *CSM =
+ CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope))
+ NewMD = MDNode::concatenate(NewMD, CSM);
+ NI->setMetadata(LLVMContext::MD_alias_scope, NewMD);
+ } else if (NI->mayReadOrWriteMemory()) {
+ if (MDNode *M =
+ CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope))
+ NI->setMetadata(LLVMContext::MD_alias_scope, M);
+ }
+
+ if (MDNode *M = NI->getMetadata(LLVMContext::MD_noalias)) {
+ MDNode *NewMD = MDMap[M];
+ // If the call site also had noalias metadata (a list of scopes with
+ // which instructions inside it don't alias), propagate those scopes to
+ // the inlined instructions.
+ if (MDNode *CSM =
+ CS.getInstruction()->getMetadata(LLVMContext::MD_noalias))
+ NewMD = MDNode::concatenate(NewMD, CSM);
+ NI->setMetadata(LLVMContext::MD_noalias, NewMD);
+ } else if (NI->mayReadOrWriteMemory()) {
+ if (MDNode *M = CS.getInstruction()->getMetadata(LLVMContext::MD_noalias))
+ NI->setMetadata(LLVMContext::MD_noalias, M);
+ }
+ }
+}
+
+/// AddAliasScopeMetadata - If the inlined function has noalias arguments, then
+/// add new alias scopes for each noalias argument, tag the mapped noalias
+/// parameters with noalias metadata specifying the new scope, and tag all
+/// non-derived loads, stores and memory intrinsics with the new alias scopes.
+static void AddAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap,
+ const DataLayout *DL, AliasAnalysis *AA) {
+ if (!EnableNoAliasConversion)
+ return;
+
+ const Function *CalledFunc = CS.getCalledFunction();
+ SmallVector<const Argument *, 4> NoAliasArgs;
+
+ for (Function::const_arg_iterator I = CalledFunc->arg_begin(),
+ E = CalledFunc->arg_end(); I != E; ++I) {
+ if (I->hasNoAliasAttr() && !I->hasNUses(0))
+ NoAliasArgs.push_back(I);
+ }
+
+ if (NoAliasArgs.empty())
+ return;
+
+ // To do a good job, if a noalias variable is captured, we need to know if
+ // the capture point dominates the particular use we're considering.
+ DominatorTree DT;
+ DT.recalculate(const_cast<Function&>(*CalledFunc));
+
+ // noalias indicates that pointer values based on the argument do not alias
+ // pointer values which are not based on it. So we add a new "scope" for each
+ // noalias function argument. Accesses using pointers based on that argument
+ // become part of that alias scope, accesses using pointers not based on that
+ // argument are tagged as noalias with that scope.
+
+ DenseMap<const Argument *, MDNode *> NewScopes;
+ MDBuilder MDB(CalledFunc->getContext());
+
+ // Create a new scope domain for this function.
+ MDNode *NewDomain =
+ MDB.createAnonymousAliasScopeDomain(CalledFunc->getName());
+ for (unsigned i = 0, e = NoAliasArgs.size(); i != e; ++i) {
+ const Argument *A = NoAliasArgs[i];
+
+ std::string Name = CalledFunc->getName();
+ if (A->hasName()) {
+ Name += ": %";
+ Name += A->getName();
+ } else {
+ Name += ": argument ";
+ Name += utostr(i);
+ }
+
+ // Note: We always create a new anonymous root here. This is true regardless
+ // of the linkage of the callee because the aliasing "scope" is not just a
+ // property of the callee, but also all control dependencies in the caller.
+ MDNode *NewScope = MDB.createAnonymousAliasScope(NewDomain, Name);
+ NewScopes.insert(std::make_pair(A, NewScope));
+ }
+
+ // Iterate over all new instructions in the map; for all memory-access
+ // instructions, add the alias scope metadata.
+ for (ValueToValueMapTy::iterator VMI = VMap.begin(), VMIE = VMap.end();
+ VMI != VMIE; ++VMI) {
+ if (const Instruction *I = dyn_cast<Instruction>(VMI->first)) {
+ if (!VMI->second)
+ continue;
+
+ Instruction *NI = dyn_cast<Instruction>(VMI->second);
+ if (!NI)
+ continue;
+
+ bool IsArgMemOnlyCall = false, IsFuncCall = false;
+ SmallVector<const Value *, 2> PtrArgs;
+
+ if (const LoadInst *LI = dyn_cast<LoadInst>(I))
+ PtrArgs.push_back(LI->getPointerOperand());
+ else if (const StoreInst *SI = dyn_cast<StoreInst>(I))
+ PtrArgs.push_back(SI->getPointerOperand());
+ else if (const VAArgInst *VAAI = dyn_cast<VAArgInst>(I))
+ PtrArgs.push_back(VAAI->getPointerOperand());
+ else if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I))
+ PtrArgs.push_back(CXI->getPointerOperand());
+ else if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I))
+ PtrArgs.push_back(RMWI->getPointerOperand());
+ else if (ImmutableCallSite ICS = ImmutableCallSite(I)) {
+ // If we know that the call does not access memory, then we'll still
+ // know that about the inlined clone of this call site, and we don't
+ // need to add metadata.
+ if (ICS.doesNotAccessMemory())
+ continue;
+
+ IsFuncCall = true;
+ if (AA) {
+ AliasAnalysis::ModRefBehavior MRB = AA->getModRefBehavior(ICS);
+ if (MRB == AliasAnalysis::OnlyAccessesArgumentPointees ||
+ MRB == AliasAnalysis::OnlyReadsArgumentPointees)
+ IsArgMemOnlyCall = true;
+ }
+
+ for (ImmutableCallSite::arg_iterator AI = ICS.arg_begin(),
+ AE = ICS.arg_end(); AI != AE; ++AI) {
+ // We need to check the underlying objects of all arguments, not just
+ // the pointer arguments, because we might be passing pointers as
+ // integers, etc.
+ // However, if we know that the call only accesses pointer arguments,
+ // then we only need to check the pointer arguments.
+ if (IsArgMemOnlyCall && !(*AI)->getType()->isPointerTy())
+ continue;
+
+ PtrArgs.push_back(*AI);
+ }
+ }
+
+ // If we found no pointers, then this instruction is not suitable for
+ // pairing with an instruction to receive aliasing metadata.
+ // However, if this is a call, this we might just alias with none of the
+ // noalias arguments.
+ if (PtrArgs.empty() && !IsFuncCall)
continue;
+
+ // It is possible that there is only one underlying object, but you
+ // need to go through several PHIs to see it, and thus could be
+ // repeated in the Objects list.
+ SmallPtrSet<const Value *, 4> ObjSet;
+ SmallVector<Metadata *, 4> Scopes, NoAliases;
+
+ SmallSetVector<const Argument *, 4> NAPtrArgs;
+ for (unsigned i = 0, ie = PtrArgs.size(); i != ie; ++i) {
+ SmallVector<Value *, 4> Objects;
+ GetUnderlyingObjects(const_cast<Value*>(PtrArgs[i]),
+ Objects, DL, /* MaxLookup = */ 0);
+
+ for (Value *O : Objects)
+ ObjSet.insert(O);
}
- if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
- // An UnwindInst requires special handling when it gets inlined into an
- // invoke site. Once this happens, we know that the unwind would cause
- // a control transfer to the invoke exception destination, so we can
- // transform it into a direct branch to the exception destination.
- BranchInst::Create(InvokeDest, UI);
+ // Figure out if we're derived from anything that is not a noalias
+ // argument.
+ bool CanDeriveViaCapture = false, UsesAliasingPtr = false;
+ for (const Value *V : ObjSet) {
+ // Is this value a constant that cannot be derived from any pointer
+ // value (we need to exclude constant expressions, for example, that
+ // are formed from arithmetic on global symbols).
+ bool IsNonPtrConst = isa<ConstantInt>(V) || isa<ConstantFP>(V) ||
+ isa<ConstantPointerNull>(V) ||
+ isa<ConstantDataVector>(V) || isa<UndefValue>(V);
+ if (IsNonPtrConst)
+ continue;
+
+ // If this is anything other than a noalias argument, then we cannot
+ // completely describe the aliasing properties using alias.scope
+ // metadata (and, thus, won't add any).
+ if (const Argument *A = dyn_cast<Argument>(V)) {
+ if (!A->hasNoAliasAttr())
+ UsesAliasingPtr = true;
+ } else {
+ UsesAliasingPtr = true;
+ }
- // Delete the unwind instruction!
- UI->eraseFromParent();
+ // If this is not some identified function-local object (which cannot
+ // directly alias a noalias argument), or some other argument (which,
+ // by definition, also cannot alias a noalias argument), then we could
+ // alias a noalias argument that has been captured).
+ if (!isa<Argument>(V) &&
+ !isIdentifiedFunctionLocal(const_cast<Value*>(V)))
+ CanDeriveViaCapture = true;
+ }
- // Update any PHI nodes in the exceptional block to indicate that
- // there is now a new entry in them.
- Invoke.addIncomingPHIValuesFor(BB);
+ // A function call can always get captured noalias pointers (via other
+ // parameters, globals, etc.).
+ if (IsFuncCall && !IsArgMemOnlyCall)
+ CanDeriveViaCapture = true;
+
+ // First, we want to figure out all of the sets with which we definitely
+ // don't alias. Iterate over all noalias set, and add those for which:
+ // 1. The noalias argument is not in the set of objects from which we
+ // definitely derive.
+ // 2. The noalias argument has not yet been captured.
+ // An arbitrary function that might load pointers could see captured
+ // noalias arguments via other noalias arguments or globals, and so we
+ // must always check for prior capture.
+ for (const Argument *A : NoAliasArgs) {
+ if (!ObjSet.count(A) && (!CanDeriveViaCapture ||
+ // It might be tempting to skip the
+ // PointerMayBeCapturedBefore check if
+ // A->hasNoCaptureAttr() is true, but this is
+ // incorrect because nocapture only guarantees
+ // that no copies outlive the function, not
+ // that the value cannot be locally captured.
+ !PointerMayBeCapturedBefore(A,
+ /* ReturnCaptures */ false,
+ /* StoreCaptures */ false, I, &DT)))
+ NoAliases.push_back(NewScopes[A]);
+ }
+
+ if (!NoAliases.empty())
+ NI->setMetadata(LLVMContext::MD_noalias,
+ MDNode::concatenate(
+ NI->getMetadata(LLVMContext::MD_noalias),
+ MDNode::get(CalledFunc->getContext(), NoAliases)));
+
+ // Next, we want to figure out all of the sets to which we might belong.
+ // We might belong to a set if the noalias argument is in the set of
+ // underlying objects. If there is some non-noalias argument in our list
+ // of underlying objects, then we cannot add a scope because the fact
+ // that some access does not alias with any set of our noalias arguments
+ // cannot itself guarantee that it does not alias with this access
+ // (because there is some pointer of unknown origin involved and the
+ // other access might also depend on this pointer). We also cannot add
+ // scopes to arbitrary functions unless we know they don't access any
+ // non-parameter pointer-values.
+ bool CanAddScopes = !UsesAliasingPtr;
+ if (CanAddScopes && IsFuncCall)
+ CanAddScopes = IsArgMemOnlyCall;
+
+ if (CanAddScopes)
+ for (const Argument *A : NoAliasArgs) {
+ if (ObjSet.count(A))
+ Scopes.push_back(NewScopes[A]);
+ }
+
+ if (!Scopes.empty())
+ NI->setMetadata(
+ LLVMContext::MD_alias_scope,
+ MDNode::concatenate(NI->getMetadata(LLVMContext::MD_alias_scope),
+ MDNode::get(CalledFunc->getContext(), Scopes)));
}
}
+}
- // Now that everything is happy, we have one final detail. The PHI nodes in
- // the exception destination block still have entries due to the original
- // invoke instruction. Eliminate these entries (which might even delete the
- // PHI node) now.
- InvokeDest->removePredecessor(II->getParent());
+/// If the inlined function has non-byval align arguments, then
+/// add @llvm.assume-based alignment assumptions to preserve this information.
+static void AddAlignmentAssumptions(CallSite CS, InlineFunctionInfo &IFI) {
+ if (!PreserveAlignmentAssumptions || !IFI.DL)
+ return;
+
+ // To avoid inserting redundant assumptions, we should check for assumptions
+ // already in the caller. To do this, we might need a DT of the caller.
+ DominatorTree DT;
+ bool DTCalculated = false;
+
+ Function *CalledFunc = CS.getCalledFunction();
+ for (Function::arg_iterator I = CalledFunc->arg_begin(),
+ E = CalledFunc->arg_end();
+ I != E; ++I) {
+ unsigned Align = I->getType()->isPointerTy() ? I->getParamAlignment() : 0;
+ if (Align && !I->hasByValOrInAllocaAttr() && !I->hasNUses(0)) {
+ if (!DTCalculated) {
+ DT.recalculate(const_cast<Function&>(*CS.getInstruction()->getParent()
+ ->getParent()));
+ DTCalculated = true;
+ }
+
+ // If we can already prove the asserted alignment in the context of the
+ // caller, then don't bother inserting the assumption.
+ Value *Arg = CS.getArgument(I->getArgNo());
+ if (getKnownAlignment(Arg, IFI.DL,
+ &IFI.ACT->getAssumptionCache(*CalledFunc),
+ CS.getInstruction(), &DT) >= Align)
+ continue;
+
+ IRBuilder<>(CS.getInstruction()).CreateAlignmentAssumption(*IFI.DL, Arg,
+ Align);
+ }
+ }
}
/// UpdateCallGraphAfterInlining - Once we have cloned code over from a callee
ValueToValueMapTy::iterator VMI = VMap.find(OrigCall);
// Only copy the edge if the call was inlined!
- if (VMI == VMap.end() || VMI->second == 0)
+ if (VMI == VMap.end() || VMI->second == nullptr)
continue;
// If the call was inlined, but then constant folded, there is no edge to
// add. Check for this case.
Instruction *NewCall = dyn_cast<Instruction>(VMI->second);
- if (NewCall == 0) continue;
+ if (!NewCall) continue;
// Remember that this call site got inlined for the client of
// InlineFunction.
// happens, set the callee of the new call site to a more precise
// destination. This can also happen if the call graph node of the caller
// was just unnecessarily imprecise.
- if (I->second->getFunction() == 0)
+ if (!I->second->getFunction())
if (Function *F = CallSite(NewCall).getCalledFunction()) {
// Indirect call site resolved to direct call.
CallerNode->addCalledFunction(CallSite(NewCall), CG[F]);
CallerNode->removeCallEdgeFor(CS);
}
+static void HandleByValArgumentInit(Value *Dst, Value *Src, Module *M,
+ BasicBlock *InsertBlock,
+ InlineFunctionInfo &IFI) {
+ Type *AggTy = cast<PointerType>(Src->getType())->getElementType();
+ IRBuilder<> Builder(InsertBlock->begin());
+
+ Value *Size;
+ if (IFI.DL == nullptr)
+ Size = ConstantExpr::getSizeOf(AggTy);
+ else
+ Size = Builder.getInt64(IFI.DL->getTypeStoreSize(AggTy));
+
+ // Always generate a memcpy of alignment 1 here because we don't know
+ // the alignment of the src pointer. Other optimizations can infer
+ // better alignment.
+ Builder.CreateMemCpy(Dst, Src, Size, /*Align=*/1);
+}
+
/// HandleByValArgument - When inlining a call site that has a byval argument,
/// we have to make the implicit memcpy explicit by adding it.
static Value *HandleByValArgument(Value *Arg, Instruction *TheCall,
const Function *CalledFunc,
InlineFunctionInfo &IFI,
unsigned ByValAlignment) {
- Type *AggTy = cast<PointerType>(Arg->getType())->getElementType();
+ PointerType *ArgTy = cast<PointerType>(Arg->getType());
+ Type *AggTy = ArgTy->getElementType();
+
+ Function *Caller = TheCall->getParent()->getParent();
// If the called function is readonly, then it could not mutate the caller's
// copy of the byval'd memory. In this case, it is safe to elide the copy and
// If the pointer is already known to be sufficiently aligned, or if we can
// round it up to a larger alignment, then we don't need a temporary.
- if (getOrEnforceKnownAlignment(Arg, ByValAlignment,
- IFI.TD) >= ByValAlignment)
+ if (getOrEnforceKnownAlignment(Arg, ByValAlignment, IFI.DL,
+ &IFI.ACT->getAssumptionCache(*Caller),
+ TheCall) >= ByValAlignment)
return Arg;
// Otherwise, we have to make a memcpy to get a safe alignment. This is bad
// for code quality, but rarely happens and is required for correctness.
}
-
- LLVMContext &Context = Arg->getContext();
- Type *VoidPtrTy = Type::getInt8PtrTy(Context);
-
- // Create the alloca. If we have TargetData, use nice alignment.
+ // Create the alloca. If we have DataLayout, use nice alignment.
unsigned Align = 1;
- if (IFI.TD)
- Align = IFI.TD->getPrefTypeAlignment(AggTy);
+ if (IFI.DL)
+ Align = IFI.DL->getPrefTypeAlignment(AggTy);
// If the byval had an alignment specified, we *must* use at least that
// alignment, as it is required by the byval argument (and uses of the
// pointer inside the callee).
Align = std::max(Align, ByValAlignment);
- Function *Caller = TheCall->getParent()->getParent();
-
- Value *NewAlloca = new AllocaInst(AggTy, 0, Align, Arg->getName(),
+ Value *NewAlloca = new AllocaInst(AggTy, nullptr, Align, Arg->getName(),
&*Caller->begin()->begin());
- // Emit a memcpy.
- Type *Tys[3] = {VoidPtrTy, VoidPtrTy, Type::getInt64Ty(Context)};
- Function *MemCpyFn = Intrinsic::getDeclaration(Caller->getParent(),
- Intrinsic::memcpy,
- Tys);
- Value *DestCast = new BitCastInst(NewAlloca, VoidPtrTy, "tmp", TheCall);
- Value *SrcCast = new BitCastInst(Arg, VoidPtrTy, "tmp", TheCall);
-
- Value *Size;
- if (IFI.TD == 0)
- Size = ConstantExpr::getSizeOf(AggTy);
- else
- Size = ConstantInt::get(Type::getInt64Ty(Context),
- IFI.TD->getTypeStoreSize(AggTy));
-
- // Always generate a memcpy of alignment 1 here because we don't know
- // the alignment of the src pointer. Other optimizations can infer
- // better alignment.
- Value *CallArgs[] = {
- DestCast, SrcCast, Size,
- ConstantInt::get(Type::getInt32Ty(Context), 1),
- ConstantInt::getFalse(Context) // isVolatile
- };
- IRBuilder<>(TheCall).CreateCall(MemCpyFn, CallArgs);
+ IFI.StaticAllocas.push_back(cast<AllocaInst>(NewAlloca));
// Uses of the argument in the function should use our new alloca
// instead.
// 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)) {
+ for (User *U : V->users()) {
+ if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(U)) {
switch (II->getIntrinsicID()) {
default: break;
case Intrinsic::lifetime_start:
// hasLifetimeMarkers - Check whether the given alloca already has
// lifetime.start or lifetime.end intrinsics.
static bool hasLifetimeMarkers(AllocaInst *AI) {
- Type *Int8PtrTy = Type::getInt8PtrTy(AI->getType()->getContext());
- if (AI->getType() == Int8PtrTy)
+ Type *Ty = AI->getType();
+ Type *Int8PtrTy = Type::getInt8PtrTy(Ty->getContext(),
+ Ty->getPointerAddressSpace());
+ if (Ty == Int8PtrTy)
return isUsedByLifetimeMarker(AI);
// Do a scan to find all the casts to i8*.
- for (Value::use_iterator I = AI->use_begin(), E = AI->use_end(); I != E;
- ++I) {
- if (I->getType() != Int8PtrTy) continue;
- if (I->stripPointerCasts() != AI) continue;
- if (isUsedByLifetimeMarker(*I))
+ for (User *U : AI->users()) {
+ if (U->getType() != Int8PtrTy) continue;
+ if (U->stripPointerCasts() != AI) continue;
+ if (isUsedByLifetimeMarker(U))
return true;
}
return false;
}
-/// updateInlinedAtInfo - Helper function used by fixupLineNumbers to recursively
-/// update InlinedAtEntry of a DebugLoc.
-static DebugLoc updateInlinedAtInfo(const DebugLoc &DL,
- const DebugLoc &InlinedAtDL,
- LLVMContext &Ctx) {
- if (MDNode *IA = DL.getInlinedAt(Ctx)) {
- DebugLoc NewInlinedAtDL
- = updateInlinedAtInfo(DebugLoc::getFromDILocation(IA), InlinedAtDL, Ctx);
- return DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(Ctx),
- NewInlinedAtDL.getAsMDNode(Ctx));
+/// Rebuild the entire inlined-at chain for this instruction so that the top of
+/// the chain now is inlined-at the new call site.
+static DebugLoc
+updateInlinedAtInfo(DebugLoc DL, MDLocation *InlinedAtNode,
+ LLVMContext &Ctx,
+ DenseMap<const MDLocation *, MDLocation *> &IANodes) {
+ SmallVector<MDLocation*, 3> InlinedAtLocations;
+ MDLocation *Last = InlinedAtNode;
+ DebugLoc CurInlinedAt = DL;
+
+ // Gather all the inlined-at nodes
+ while (MDLocation *IA =
+ cast_or_null<MDLocation>(CurInlinedAt.getInlinedAt(Ctx))) {
+ // Skip any we've already built nodes for
+ if (MDLocation *Found = IANodes[IA]) {
+ Last = Found;
+ break;
+ }
+
+ InlinedAtLocations.push_back(IA);
+ CurInlinedAt = DebugLoc::getFromDILocation(IA);
}
-
- return DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(Ctx),
- InlinedAtDL.getAsMDNode(Ctx));
-}
+ // Starting from the top, rebuild the nodes to point to the new inlined-at
+ // location (then rebuilding the rest of the chain behind it) and update the
+ // map of already-constructed inlined-at nodes.
+ for (auto I = InlinedAtLocations.rbegin(), E = InlinedAtLocations.rend();
+ I != E; ++I) {
+ const MDLocation *MD = *I;
+ Last = IANodes[MD] = MDLocation::getDistinct(
+ Ctx, MD->getLine(), MD->getColumn(), MD->getScope(), Last);
+ }
+
+ // And finally create the normal location for this instruction, referring to
+ // the new inlined-at chain.
+ return DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(Ctx), Last);
+}
/// fixupLineNumbers - Update inlined instructions' line numbers to
/// to encode location where these instructions are inlined.
static void fixupLineNumbers(Function *Fn, Function::iterator FI,
- Instruction *TheCall) {
+ Instruction *TheCall) {
DebugLoc TheCallDL = TheCall->getDebugLoc();
if (TheCallDL.isUnknown())
return;
+ auto &Ctx = Fn->getContext();
+ auto *InlinedAtNode = cast<MDLocation>(TheCallDL.getAsMDNode(Ctx));
+
+ // Create a unique call site, not to be confused with any other call from the
+ // same location.
+ InlinedAtNode = MDLocation::getDistinct(
+ Ctx, InlinedAtNode->getLine(), InlinedAtNode->getColumn(),
+ InlinedAtNode->getScope(), InlinedAtNode->getInlinedAt());
+
+ // Cache the inlined-at nodes as they're built so they are reused, without
+ // this every instruction's inlined-at chain would become distinct from each
+ // other.
+ DenseMap<const MDLocation *, MDLocation *> IANodes;
+
for (; FI != Fn->end(); ++FI) {
for (BasicBlock::iterator BI = FI->begin(), BE = FI->end();
BI != BE; ++BI) {
DebugLoc DL = BI->getDebugLoc();
- if (!DL.isUnknown()) {
- BI->setDebugLoc(updateInlinedAtInfo(DL, TheCallDL, BI->getContext()));
+ if (DL.isUnknown()) {
+ // If the inlined instruction has no line number, make it look as if it
+ // originates from the call location. This is important for
+ // ((__always_inline__, __nodebug__)) functions which must use caller
+ // location for all instructions in their function body.
+
+ // Don't update static allocas, as they may get moved later.
+ if (auto *AI = dyn_cast<AllocaInst>(BI))
+ if (isa<Constant>(AI->getArraySize()))
+ continue;
+
+ BI->setDebugLoc(TheCallDL);
+ } else {
+ BI->setDebugLoc(updateInlinedAtInfo(DL, InlinedAtNode, BI->getContext(), IANodes));
if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(BI)) {
LLVMContext &Ctx = BI->getContext();
MDNode *InlinedAt = BI->getDebugLoc().getInlinedAt(Ctx);
- DVI->setOperand(2, createInlinedVariable(DVI->getVariable(),
- InlinedAt, Ctx));
+ DVI->setOperand(2, MetadataAsValue::get(
+ Ctx, createInlinedVariable(DVI->getVariable(),
+ InlinedAt, Ctx)));
+ } else if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(BI)) {
+ LLVMContext &Ctx = BI->getContext();
+ MDNode *InlinedAt = BI->getDebugLoc().getInlinedAt(Ctx);
+ DDI->setOperand(1, MetadataAsValue::get(
+ Ctx, createInlinedVariable(DDI->getVariable(),
+ InlinedAt, Ctx)));
}
}
}
}
}
-// 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.
-//
-// Note that this only does one level of inlining. For example, if the
-// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now
-// exists in the instruction stream. Similarly this will inline a recursive
-// function by one level.
-//
-bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
+/// 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.
+///
+/// Note that this only does one level of inlining. For example, if the
+/// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now
+/// exists in the instruction stream. Similarly this will inline a recursive
+/// function by one level.
+bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI,
+ bool InsertLifetime) {
Instruction *TheCall = CS.getInstruction();
- LLVMContext &Context = TheCall->getContext();
assert(TheCall->getParent() && TheCall->getParent()->getParent() &&
"Instruction not in function!");
IFI.reset();
const Function *CalledFunc = CS.getCalledFunction();
- if (CalledFunc == 0 || // Can't inline external function or indirect
+ if (!CalledFunc || // Can't inline external function or indirect
CalledFunc->isDeclaration() || // call, or call to a vararg function!
CalledFunc->getFunctionType()->isVarArg()) return false;
- // If the call to the callee is not a tail call, we must clear the 'tail'
- // flags on any calls that we inline.
- bool MustClearTailCallFlags =
- !(isa<CallInst>(TheCall) && cast<CallInst>(TheCall)->isTailCall());
-
// If the call to the callee cannot throw, set the 'nounwind' flag on any
// calls that we inline.
bool MarkNoUnwind = CS.doesNotThrow();
return false;
}
+ // Get the personality function from the callee if it contains a landing pad.
+ Value *CalleePersonality = nullptr;
+ for (Function::const_iterator I = CalledFunc->begin(), E = CalledFunc->end();
+ I != E; ++I)
+ if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
+ const BasicBlock *BB = II->getUnwindDest();
+ const LandingPadInst *LP = BB->getLandingPadInst();
+ CalleePersonality = LP->getPersonalityFn();
+ break;
+ }
+
+ // Find the personality function used by the landing pads of the caller. If it
+ // exists, then check to see that it matches the personality function used in
+ // the callee.
+ if (CalleePersonality) {
+ for (Function::const_iterator I = Caller->begin(), E = Caller->end();
+ I != E; ++I)
+ if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
+ const BasicBlock *BB = II->getUnwindDest();
+ const LandingPadInst *LP = BB->getLandingPadInst();
+
+ // If the personality functions match, then we can perform the
+ // inlining. Otherwise, we can't inline.
+ // TODO: This isn't 100% true. Some personality functions are proper
+ // supersets of others and can be used in place of the other.
+ if (LP->getPersonalityFn() != CalleePersonality)
+ return false;
+
+ break;
+ }
+ }
+
// Get an iterator to the last basic block in the function, which will have
// the new function inlined after it.
- //
Function::iterator LastBlock = &Caller->back();
// Make sure to capture all of the return instructions from the cloned
{ // Scope to destroy VMap after cloning.
ValueToValueMapTy VMap;
+ // Keep a list of pair (dst, src) to emit byval initializations.
+ SmallVector<std::pair<Value*, Value*>, 4> ByValInit;
assert(CalledFunc->arg_size() == CS.arg_size() &&
"No varargs calls can be inlined!");
// by them explicit. However, we don't do this if the callee is readonly
// or readnone, because the copy would be unneeded: the callee doesn't
// modify the struct.
- if (CalledFunc->paramHasAttr(ArgNo+1, Attribute::ByVal)) {
+ if (CS.isByValArgument(ArgNo)) {
ActualArg = HandleByValArgument(ActualArg, TheCall, CalledFunc, IFI,
CalledFunc->getParamAlignment(ArgNo+1));
-
- // Calls that we inline may use the new alloca, so we need to clear
- // their 'tail' flags if HandleByValArgument introduced a new alloca and
- // the callee has calls.
- MustClearTailCallFlags |= ActualArg != *AI;
+ if (ActualArg != *AI)
+ ByValInit.push_back(std::make_pair(ActualArg, (Value*) *AI));
}
VMap[I] = ActualArg;
}
+ // Add alignment assumptions if necessary. We do this before the inlined
+ // instructions are actually cloned into the caller so that we can easily
+ // check what will be known at the start of the inlined code.
+ AddAlignmentAssumptions(CS, IFI);
+
// We want the inliner to prune the code as it copies. We would LOVE to
// have no dead or constant instructions leftover after inlining occurs
// (which can happen, e.g., because an argument was constant), but we'll be
// happy with whatever the cloner can do.
CloneAndPruneFunctionInto(Caller, CalledFunc, VMap,
/*ModuleLevelChanges=*/false, Returns, ".i",
- &InlinedFunctionInfo, IFI.TD, TheCall);
+ &InlinedFunctionInfo, IFI.DL, TheCall);
// Remember the first block that is newly cloned over.
FirstNewBlock = LastBlock; ++FirstNewBlock;
+ // Inject byval arguments initialization.
+ for (std::pair<Value*, Value*> &Init : ByValInit)
+ HandleByValArgumentInit(Init.first, Init.second, Caller->getParent(),
+ FirstNewBlock, IFI);
+
// Update the callgraph if requested.
if (IFI.CG)
UpdateCallGraphAfterInlining(CS, FirstNewBlock, VMap, IFI);
// Update inlined instructions' line number information.
fixupLineNumbers(Caller, FirstNewBlock, TheCall);
+
+ // Clone existing noalias metadata if necessary.
+ CloneAliasScopeMetadata(CS, VMap);
+
+ // Add noalias metadata if necessary.
+ AddAliasScopeMetadata(CS, VMap, IFI.DL, IFI.AA);
+
+ // FIXME: We could register any cloned assumptions instead of clearing the
+ // whole function's cache.
+ if (IFI.ACT)
+ IFI.ACT->getAssumptionCache(*Caller).clear();
}
// If there are any alloca instructions in the block that used to be the entry
// block for the callee, move them to the entry block of the caller. First
// calculate which instruction they should be inserted before. We insert the
// instructions at the end of the current alloca list.
- //
{
BasicBlock::iterator InsertPoint = Caller->begin()->begin();
for (BasicBlock::iterator I = FirstNewBlock->begin(),
E = FirstNewBlock->end(); I != E; ) {
AllocaInst *AI = dyn_cast<AllocaInst>(I++);
- if (AI == 0) continue;
+ if (!AI) continue;
// If the alloca is now dead, remove it. This often occurs due to code
// specialization.
FirstNewBlock->getInstList(),
AI, I);
}
+ // Move any dbg.declares describing the allocas into the entry basic block.
+ DIBuilder DIB(*Caller->getParent());
+ for (auto &AI : IFI.StaticAllocas)
+ replaceDbgDeclareForAlloca(AI, AI, DIB, /*Deref=*/false);
+ }
+
+ bool InlinedMustTailCalls = false;
+ if (InlinedFunctionInfo.ContainsCalls) {
+ CallInst::TailCallKind CallSiteTailKind = CallInst::TCK_None;
+ if (CallInst *CI = dyn_cast<CallInst>(TheCall))
+ CallSiteTailKind = CI->getTailCallKind();
+
+ for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E;
+ ++BB) {
+ for (Instruction &I : *BB) {
+ CallInst *CI = dyn_cast<CallInst>(&I);
+ if (!CI)
+ continue;
+
+ // We need to reduce the strength of any inlined tail calls. For
+ // musttail, we have to avoid introducing potential unbounded stack
+ // growth. For example, if functions 'f' and 'g' are mutually recursive
+ // with musttail, we can inline 'g' into 'f' so long as we preserve
+ // musttail on the cloned call to 'f'. If either the inlined call site
+ // or the cloned call site is *not* musttail, the program already has
+ // one frame of stack growth, so it's safe to remove musttail. Here is
+ // a table of example transformations:
+ //
+ // f -> musttail g -> musttail f ==> f -> musttail f
+ // f -> musttail g -> tail f ==> f -> tail f
+ // f -> g -> musttail f ==> f -> f
+ // f -> g -> tail f ==> f -> f
+ CallInst::TailCallKind ChildTCK = CI->getTailCallKind();
+ ChildTCK = std::min(CallSiteTailKind, ChildTCK);
+ CI->setTailCallKind(ChildTCK);
+ InlinedMustTailCalls |= CI->isMustTailCall();
+
+ // Calls inlined through a 'nounwind' call site should be marked
+ // 'nounwind'.
+ if (MarkNoUnwind)
+ CI->setDoesNotThrow();
+ }
+ }
}
// Leave lifetime markers for the static alloca's, scoping them to the
// function we just inlined.
- if (!IFI.StaticAllocas.empty()) {
+ if (InsertLifetime && !IFI.StaticAllocas.empty()) {
IRBuilder<> builder(FirstNewBlock->begin());
for (unsigned ai = 0, ae = IFI.StaticAllocas.size(); ai != ae; ++ai) {
AllocaInst *AI = IFI.StaticAllocas[ai];
if (hasLifetimeMarkers(AI))
continue;
- builder.CreateLifetimeStart(AI);
- for (unsigned ri = 0, re = Returns.size(); ri != re; ++ri) {
- IRBuilder<> builder(Returns[ri]);
- builder.CreateLifetimeEnd(AI);
+ // Try to determine the size of the allocation.
+ ConstantInt *AllocaSize = nullptr;
+ if (ConstantInt *AIArraySize =
+ dyn_cast<ConstantInt>(AI->getArraySize())) {
+ if (IFI.DL) {
+ Type *AllocaType = AI->getAllocatedType();
+ uint64_t AllocaTypeSize = IFI.DL->getTypeAllocSize(AllocaType);
+ uint64_t AllocaArraySize = AIArraySize->getLimitedValue();
+ assert(AllocaArraySize > 0 && "array size of AllocaInst is zero");
+ // Check that array size doesn't saturate uint64_t and doesn't
+ // overflow when it's multiplied by type size.
+ if (AllocaArraySize != ~0ULL &&
+ UINT64_MAX / AllocaArraySize >= AllocaTypeSize) {
+ AllocaSize = ConstantInt::get(Type::getInt64Ty(AI->getContext()),
+ AllocaArraySize * AllocaTypeSize);
+ }
+ }
+ }
+
+ builder.CreateLifetimeStart(AI, AllocaSize);
+ for (ReturnInst *RI : Returns) {
+ // Don't insert llvm.lifetime.end calls between a musttail call and a
+ // return. The return kills all local allocas.
+ if (InlinedMustTailCalls &&
+ RI->getParent()->getTerminatingMustTailCall())
+ continue;
+ IRBuilder<>(RI).CreateLifetimeEnd(AI, AllocaSize);
}
}
}
// Insert a call to llvm.stackrestore before any return instructions in the
// inlined function.
- for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
- IRBuilder<>(Returns[i]).CreateCall(StackRestore, SavedPtr);
- }
-
- // Count the number of StackRestore calls we insert.
- unsigned NumStackRestores = Returns.size();
-
- // If we are inlining an invoke instruction, insert restores before each
- // unwind. These unwinds will be rewritten into branches later.
- if (InlinedFunctionInfo.ContainsUnwinds && isa<InvokeInst>(TheCall)) {
- for (Function::iterator BB = FirstNewBlock, E = Caller->end();
- BB != E; ++BB)
- if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
- IRBuilder<>(UI).CreateCall(StackRestore, SavedPtr);
- ++NumStackRestores;
- }
+ for (ReturnInst *RI : Returns) {
+ // Don't insert llvm.stackrestore calls between a musttail call and a
+ // return. The return will restore the stack pointer.
+ if (InlinedMustTailCalls && RI->getParent()->getTerminatingMustTailCall())
+ continue;
+ IRBuilder<>(RI).CreateCall(StackRestore, SavedPtr);
}
}
- // If we are inlining tail call instruction through a call site that isn't
- // marked 'tail', we must remove the tail marker for any calls in the inlined
- // code. Also, calls inlined through a 'nounwind' call site should be marked
- // 'nounwind'.
- if (InlinedFunctionInfo.ContainsCalls &&
- (MustClearTailCallFlags || MarkNoUnwind)) {
- for (Function::iterator BB = FirstNewBlock, E = Caller->end();
- BB != E; ++BB)
- for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
- if (CallInst *CI = dyn_cast<CallInst>(I)) {
- if (MustClearTailCallFlags)
- CI->setTailCall(false);
- if (MarkNoUnwind)
- CI->setDoesNotThrow();
- }
- }
+ // If we are inlining for an invoke instruction, we must make sure to rewrite
+ // any call instructions into invoke instructions.
+ if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall))
+ HandleInlinedInvoke(II, FirstNewBlock, InlinedFunctionInfo);
- // If we are inlining through a 'nounwind' call site then any inlined 'unwind'
- // instructions are unreachable.
- if (InlinedFunctionInfo.ContainsUnwinds && MarkNoUnwind)
- for (Function::iterator BB = FirstNewBlock, E = Caller->end();
- BB != E; ++BB) {
- TerminatorInst *Term = BB->getTerminator();
- if (isa<UnwindInst>(Term)) {
- new UnreachableInst(Context, Term);
- BB->getInstList().erase(Term);
+ // Handle any inlined musttail call sites. In order for a new call site to be
+ // musttail, the source of the clone and the inlined call site must have been
+ // musttail. Therefore it's safe to return without merging control into the
+ // phi below.
+ if (InlinedMustTailCalls) {
+ // Check if we need to bitcast the result of any musttail calls.
+ Type *NewRetTy = Caller->getReturnType();
+ bool NeedBitCast = !TheCall->use_empty() && TheCall->getType() != NewRetTy;
+
+ // Handle the returns preceded by musttail calls separately.
+ SmallVector<ReturnInst *, 8> NormalReturns;
+ for (ReturnInst *RI : Returns) {
+ CallInst *ReturnedMustTail =
+ RI->getParent()->getTerminatingMustTailCall();
+ if (!ReturnedMustTail) {
+ NormalReturns.push_back(RI);
+ continue;
}
+ if (!NeedBitCast)
+ continue;
+
+ // Delete the old return and any preceding bitcast.
+ BasicBlock *CurBB = RI->getParent();
+ auto *OldCast = dyn_cast_or_null<BitCastInst>(RI->getReturnValue());
+ RI->eraseFromParent();
+ if (OldCast)
+ OldCast->eraseFromParent();
+
+ // Insert a new bitcast and return with the right type.
+ IRBuilder<> Builder(CurBB);
+ Builder.CreateRet(Builder.CreateBitCast(ReturnedMustTail, NewRetTy));
}
- // If we are inlining for an invoke instruction, we must make sure to rewrite
- // any inlined 'unwind' instructions into branches to the invoke exception
- // destination, and call instructions into invoke instructions.
- if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall))
- HandleInlinedInvoke(II, FirstNewBlock, InlinedFunctionInfo);
+ // Leave behind the normal returns so we can merge control flow.
+ std::swap(Returns, NormalReturns);
+ }
// If we cloned in _exactly one_ basic block, and if that block ends in a
// return instruction, we splice the body of the inlined callee directly into
// If the call site was an invoke instruction, add a branch to the normal
// destination.
- if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall))
- BranchInst::Create(II->getNormalDest(), TheCall);
+ if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
+ BranchInst *NewBr = BranchInst::Create(II->getNormalDest(), TheCall);
+ NewBr->setDebugLoc(Returns[0]->getDebugLoc());
+ }
// If the return instruction returned a value, replace uses of the call with
// uses of the returned value.
// "starter" and "ender" blocks. How we accomplish this depends on whether
// this is an invoke instruction or a call instruction.
BasicBlock *AfterCallBB;
+ BranchInst *CreatedBranchToNormalDest = nullptr;
if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
// Add an unconditional branch to make this look like the CallInst case...
- BranchInst *NewBr = BranchInst::Create(II->getNormalDest(), TheCall);
+ CreatedBranchToNormalDest = BranchInst::Create(II->getNormalDest(), TheCall);
// Split the basic block. This guarantees that no PHI nodes will have to be
// updated due to new incoming edges, and make the invoke case more
// symmetric to the call case.
- AfterCallBB = OrigBB->splitBasicBlock(NewBr,
+ AfterCallBB = OrigBB->splitBasicBlock(CreatedBranchToNormalDest,
CalledFunc->getName()+".exit");
} else { // It's a call
// any users of the original call/invoke instruction.
Type *RTy = CalledFunc->getReturnType();
- PHINode *PHI = 0;
+ PHINode *PHI = nullptr;
if (Returns.size() > 1) {
// The PHI node should go at the front of the new basic block to merge all
// possible incoming values.
// Add a branch to the merge points and remove return instructions.
+ DebugLoc Loc;
for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
ReturnInst *RI = Returns[i];
- BranchInst::Create(AfterCallBB, RI);
+ BranchInst* BI = BranchInst::Create(AfterCallBB, RI);
+ Loc = RI->getDebugLoc();
+ BI->setDebugLoc(Loc);
RI->eraseFromParent();
}
+ // We need to set the debug location to *somewhere* inside the
+ // inlined function. The line number may be nonsensical, but the
+ // instruction will at least be associated with the right
+ // function.
+ if (CreatedBranchToNormalDest)
+ CreatedBranchToNormalDest->setDebugLoc(Loc);
} else if (!Returns.empty()) {
// Otherwise, if there is exactly one return value, just replace anything
// using the return value of the call with the computed value.
AfterCallBB->getInstList().splice(AfterCallBB->begin(),
ReturnBB->getInstList());
+ if (CreatedBranchToNormalDest)
+ CreatedBranchToNormalDest->setDebugLoc(Returns[0]->getDebugLoc());
+
// Delete the return instruction now and empty ReturnBB now.
Returns[0]->eraseFromParent();
ReturnBB->eraseFromParent();
// Since we are now done with the Call/Invoke, we can delete it.
TheCall->eraseFromParent();
+ // If we inlined any musttail calls and the original return is now
+ // unreachable, delete it. It can only contain a bitcast and ret.
+ if (InlinedMustTailCalls && pred_begin(AfterCallBB) == pred_end(AfterCallBB))
+ AfterCallBB->eraseFromParent();
+
// We should always be able to fold the entry block of the function into the
// single predecessor of the block...
assert(cast<BranchInst>(Br)->isUnconditional() && "splitBasicBlock broken!");
// If we inserted a phi node, check to see if it has a single value (e.g. all
// the entries are the same or undef). If so, remove the PHI so it doesn't
// block other optimizations.
- if (PHI)
- if (Value *V = SimplifyInstruction(PHI, IFI.TD)) {
+ if (PHI) {
+ if (Value *V = SimplifyInstruction(PHI, IFI.DL, nullptr, nullptr,
+ &IFI.ACT->getAssumptionCache(*Caller))) {
PHI->replaceAllUsesWith(V);
PHI->eraseFromParent();
}
+ }
return true;
}