New EH representation for MSVC compatibility
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support. Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.
Differential Revision: http://reviews.llvm.org/D11097
llvm-svn: 243766
diff --git a/llvm/lib/Transforms/Utils/InlineFunction.cpp b/llvm/lib/Transforms/Utils/InlineFunction.cpp
index c970a2d..a7515bb 100644
--- a/llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ b/llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -63,8 +63,8 @@
}
namespace {
- /// A class for recording information about inlining through an invoke.
- class InvokeInliningInfo {
+ /// A class for recording information about inlining a landing pad.
+ class LandingPadInliningInfo {
BasicBlock *OuterResumeDest; ///< Destination of the invoke's unwind.
BasicBlock *InnerResumeDest; ///< Destination for the callee's resume.
LandingPadInst *CallerLPad; ///< LandingPadInst associated with the invoke.
@@ -72,7 +72,7 @@
SmallVector<Value*, 8> UnwindDestPHIValues;
public:
- InvokeInliningInfo(InvokeInst *II)
+ LandingPadInliningInfo(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
@@ -124,7 +124,7 @@
}
/// Get or create a target for the branch from ResumeInsts.
-BasicBlock *InvokeInliningInfo::getInnerResumeDest() {
+BasicBlock *LandingPadInliningInfo::getInnerResumeDest() {
if (InnerResumeDest) return InnerResumeDest;
// Split the landing pad.
@@ -162,8 +162,8 @@
/// 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) {
+void LandingPadInliningInfo::forwardResume(
+ ResumeInst *RI, SmallPtrSetImpl<LandingPadInst *> &InlinedLPads) {
BasicBlock *Dest = getInnerResumeDest();
BasicBlock *Src = RI->getParent();
@@ -182,8 +182,8 @@
/// 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.
-static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
- InvokeInliningInfo &Invoke) {
+static BasicBlock *
+HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB, BasicBlock *UnwindEdge) {
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
Instruction *I = BBI++;
@@ -206,8 +206,7 @@
// 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.getOuterResumeDest(),
+ InvokeInst *II = InvokeInst::Create(CI->getCalledValue(), Split, UnwindEdge,
InvokeArgs, CI->getName(), BB);
II->setDebugLoc(CI->getDebugLoc());
II->setCallingConv(CI->getCallingConv());
@@ -219,12 +218,9 @@
// 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.
- Invoke.addIncomingPHIValuesFor(BB);
- return;
+ return BB;
}
+ return nullptr;
}
/// If we inlined an invoke site, we need to convert calls
@@ -233,8 +229,8 @@
/// 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),
/// and InlineCodeInfo is information about the code that got inlined.
-static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
- ClonedCodeInfo &InlinedCodeInfo) {
+static void HandleInlinedLandingPad(InvokeInst *II, BasicBlock *FirstNewBlock,
+ ClonedCodeInfo &InlinedCodeInfo) {
BasicBlock *InvokeDest = II->getUnwindDest();
Function *Caller = FirstNewBlock->getParent();
@@ -242,7 +238,7 @@
// 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.
- InvokeInliningInfo Invoke(II);
+ LandingPadInliningInfo Invoke(II);
// Get all of the inlined landing pad instructions.
SmallPtrSet<LandingPadInst*, 16> InlinedLPads;
@@ -264,7 +260,11 @@
for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){
if (InlinedCodeInfo.ContainsCalls)
- HandleCallsInBlockInlinedThroughInvoke(BB, Invoke);
+ if (BasicBlock *NewBB = HandleCallsInBlockInlinedThroughInvoke(
+ BB, Invoke.getOuterResumeDest()))
+ // Update any PHI nodes in the exceptional block to indicate that there
+ // is now a new entry in them.
+ Invoke.addIncomingPHIValuesFor(NewBB);
// Forward any resumes that are remaining here.
if (ResumeInst *RI = dyn_cast<ResumeInst>(BB->getTerminator()))
@@ -278,6 +278,102 @@
InvokeDest->removePredecessor(II->getParent());
}
+/// If we inlined an invoke site, we need to convert calls
+/// 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),
+/// and InlineCodeInfo is information about the code that got inlined.
+static void HandleInlinedEHPad(InvokeInst *II, BasicBlock *FirstNewBlock,
+ ClonedCodeInfo &InlinedCodeInfo) {
+ BasicBlock *UnwindDest = II->getUnwindDest();
+ Function *Caller = FirstNewBlock->getParent();
+
+ assert(UnwindDest->getFirstNonPHI()->isEHPad() && "unexpected BasicBlock!");
+
+ // 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.
+ SmallVector<Value *, 8> UnwindDestPHIValues;
+ llvm::BasicBlock *InvokeBB = II->getParent();
+ for (Instruction &I : *UnwindDest) {
+ // Save the value to use for this edge.
+ PHINode *PHI = dyn_cast<PHINode>(&I);
+ if (!PHI)
+ break;
+ UnwindDestPHIValues.push_back(PHI->getIncomingValueForBlock(InvokeBB));
+ }
+
+ // Add incoming-PHI values to the unwind destination block for the given basic
+ // block, using the values for the original invoke's source block.
+ auto UpdatePHINodes = [&](BasicBlock *Src) {
+ BasicBlock::iterator I = UnwindDest->begin();
+ for (Value *V : UnwindDestPHIValues) {
+ PHINode *PHI = cast<PHINode>(I);
+ PHI->addIncoming(V, Src);
+ ++I;
+ }
+ };
+
+ // Forward EH terminator instructions to the caller's invoke destination.
+ // This is as simple as connect all the instructions which 'unwind to caller'
+ // to the invoke destination.
+ for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E;
+ ++BB) {
+ Instruction *I = BB->getFirstNonPHI();
+ if (I->isEHPad()) {
+ if (auto *CEPI = dyn_cast<CatchEndPadInst>(I)) {
+ if (CEPI->unwindsToCaller()) {
+ CatchEndPadInst::Create(CEPI->getContext(), UnwindDest, CEPI);
+ CEPI->eraseFromParent();
+ UpdatePHINodes(BB);
+ }
+ } else if (auto *TPI = dyn_cast<TerminatePadInst>(I)) {
+ if (TPI->unwindsToCaller()) {
+ SmallVector<Value *, 3> TerminatePadArgs;
+ for (Value *Operand : TPI->operands())
+ TerminatePadArgs.push_back(Operand);
+ TerminatePadInst::Create(TPI->getContext(), UnwindDest, TPI);
+ TPI->eraseFromParent();
+ UpdatePHINodes(BB);
+ }
+ } else if (auto *CPI = dyn_cast<CleanupPadInst>(I)) {
+ if (CPI->getNumOperands() == 0) {
+ CleanupPadInst::Create(CPI->getType(), {UnwindDest}, CPI->getName(),
+ CPI);
+ CPI->eraseFromParent();
+ }
+ } else {
+ assert(isa<CatchPadInst>(I));
+ }
+ }
+
+ if (auto *CRI = dyn_cast<CleanupReturnInst>(BB->getTerminator())) {
+ if (CRI->unwindsToCaller()) {
+ CleanupReturnInst::Create(CRI->getContext(), CRI->getReturnValue(),
+ UnwindDest, CRI);
+ CRI->eraseFromParent();
+ UpdatePHINodes(BB);
+ }
+ }
+ }
+
+ if (InlinedCodeInfo.ContainsCalls)
+ for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E;
+ ++BB)
+ if (BasicBlock *NewBB =
+ HandleCallsInBlockInlinedThroughInvoke(BB, UnwindDest))
+ // Update any PHI nodes in the exceptional block to indicate that there
+ // is now a new entry in them.
+ UpdatePHINodes(NewBB);
+
+ // 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.
+ UnwindDest->removePredecessor(InvokeBB);
+}
+
/// 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
@@ -1204,8 +1300,15 @@
// 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 (auto *II = dyn_cast<InvokeInst>(TheCall)) {
+ BasicBlock *UnwindDest = II->getUnwindDest();
+ Instruction *FirstNonPHI = UnwindDest->getFirstNonPHI();
+ if (isa<LandingPadInst>(FirstNonPHI)) {
+ HandleInlinedLandingPad(II, FirstNewBlock, InlinedFunctionInfo);
+ } else {
+ HandleInlinedEHPad(II, FirstNewBlock, InlinedFunctionInfo);
+ }
+ }
// 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