Eliminate support for the llvm.unwind intrinisic, using the Unwind instruction instead
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8411 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index 864b6ba..17628e2 100644
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -177,38 +177,13 @@
// If we just inlined a call due to an invoke instruction, scan the inlined
// function checking for function calls that should now be made into invoke
- // instructions, and for llvm.exc.rethrow()'s which should be turned into
- // branches.
+ // instructions, and for unwind's which should be turned into branches.
if (InvokeDest)
- for (Function::iterator BB = LastBlock, E = Caller->end(); BB != E; ++BB)
+ for (Function::iterator BB = LastBlock, E = Caller->end(); BB != E; ++BB) {
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
// We only need to check for function calls: inlined invoke instructions
// require no special handling...
if (CallInst *CI = dyn_cast<CallInst>(I)) {
- if (Function *F = CI->getCalledFunction())
- if (unsigned ID = F->getIntrinsicID())
- if (ID == LLVMIntrinsic::unwind) {
- // llvm.unwind 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 *BI = new BranchInst(InvokeDest, CI);
-
- // Note that since any instructions after the rethrow/branch are
- // dead, we must delete them now (otherwise the terminator we
- // just inserted wouldn't be at the end of the basic block!)
- BasicBlock *CurBB = BB;
- while (&CurBB->back() != BI) {
- Instruction *I = &CurBB->back();
- if (!I->use_empty())
- I->replaceAllUsesWith(Constant::getNullValue(I->getType()));
- CurBB->getInstList().pop_back();
- }
-
- break; // Done with this basic block!
- }
-
// Convert this function call into an invoke instruction...
// First, split the basic block...
@@ -231,6 +206,18 @@
}
}
+ 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 *BI = new BranchInst(InvokeDest, UI);
+
+ // Delete the unwind instruction!
+ UI->getParent()->getInstList().pop_back();
+ }
+ }
+
// Now that the function is correct, make it a little bit nicer. In
// particular, move the basic blocks inserted from the end of the function
// into the space made by splitting the source basic block.
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index f47c840..1d5e4ec 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -101,32 +101,31 @@
// 'llvm.unwind'. If so, replace any invoke instructions which use this as an
// exception destination with call instructions.
//
- if (CallInst *CI = dyn_cast<CallInst>(&BB->front()))
- if (Function *F = CI->getCalledFunction())
- if (F->getIntrinsicID() == LLVMIntrinsic::unwind) {
- std::vector<BasicBlock*> Preds(pred_begin(BB), pred_end(BB));
- while (!Preds.empty()) {
- BasicBlock *Pred = Preds.back();
- if (InvokeInst *II = dyn_cast<InvokeInst>(Pred->getTerminator()))
- if (II->getExceptionalDest() == BB) {
- // Insert a new branch instruction before the invoke, because this
- // is now a fall through...
- BranchInst *BI = new BranchInst(II->getNormalDest(), II);
- Pred->getInstList().remove(II); // Take out of symbol table
-
- // Insert the call now...
- std::vector<Value*> Args(II->op_begin()+3, II->op_end());
- CallInst *CI = new CallInst(II->getCalledValue(), Args,
- II->getName(), BI);
- // If the invoke produced a value, the Call now does instead
- II->replaceAllUsesWith(CI);
- delete II;
- Changed = true;
- }
-
- Preds.pop_back();
- }
+ if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator()))
+ if (BB->begin() == BasicBlock::iterator(UI)) { // Empty block?
+ std::vector<BasicBlock*> Preds(pred_begin(BB), pred_end(BB));
+ while (!Preds.empty()) {
+ BasicBlock *Pred = Preds.back();
+ if (InvokeInst *II = dyn_cast<InvokeInst>(Pred->getTerminator()))
+ if (II->getExceptionalDest() == BB) {
+ // Insert a new branch instruction before the invoke, because this
+ // is now a fall through...
+ BranchInst *BI = new BranchInst(II->getNormalDest(), II);
+ Pred->getInstList().remove(II); // Take out of symbol table
+
+ // Insert the call now...
+ std::vector<Value*> Args(II->op_begin()+3, II->op_end());
+ CallInst *CI = new CallInst(II->getCalledValue(), Args,
+ II->getName(), BI);
+ // If the invoke produced a value, the Call now does instead
+ II->replaceAllUsesWith(CI);
+ delete II;
+ Changed = true;
+ }
+
+ Preds.pop_back();
}
+ }
// Remove basic blocks that have no predecessors... which are unreachable.
if (pred_begin(BB) == pred_end(BB) &&