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author | Chris Lattner <sabre@nondot.org> | 2003-09-10 20:34:51 +0000 |
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committer | Chris Lattner <sabre@nondot.org> | 2003-09-10 20:34:51 +0000 |
commit | f46057be77c39d972a2aacb9743ce265efa60b70 (patch) | |
tree | 3252af7d174e31f02f50c6af960e66ede0a65fc0 /lib | |
parent | d0b52cf3e744356d0242b55e94e10889dd79947f (diff) | |
download | external_llvm-f46057be77c39d972a2aacb9743ce265efa60b70.zip external_llvm-f46057be77c39d972a2aacb9743ce265efa60b70.tar.gz external_llvm-f46057be77c39d972a2aacb9743ce265efa60b70.tar.bz2 |
Expand the pass to unify all of the unwind blocks as well
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8456 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Transforms/Utils/UnifyFunctionExitNodes.cpp | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp b/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp index 71f286c3..ddce921 100644 --- a/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp +++ b/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp @@ -18,6 +18,10 @@ static RegisterOpt<UnifyFunctionExitNodes> X("mergereturn", "Unify function exit nodes"); +Pass *createUnifyFunctionExitNodesPass() { + return new UnifyFunctionExitNodes(); +} + void UnifyFunctionExitNodes::getAnalysisUsage(AnalysisUsage &AU) const{ // We preserve the non-critical-edgeness property AU.addPreservedID(BreakCriticalEdgesID); @@ -34,15 +38,36 @@ bool UnifyFunctionExitNodes::runOnFunction(Function &F) { // return. // std::vector<BasicBlock*> ReturningBlocks; + std::vector<BasicBlock*> UnwindingBlocks; for(Function::iterator I = F.begin(), E = F.end(); I != E; ++I) if (isa<ReturnInst>(I->getTerminator())) ReturningBlocks.push_back(I); + else if (isa<UnwindInst>(I->getTerminator())) + UnwindingBlocks.push_back(I); + + // Handle unwinding blocks first... + if (UnwindingBlocks.empty()) { + UnwindBlock = 0; + } else if (UnwindingBlocks.size() == 1) { + UnwindBlock = UnwindingBlocks.front(); + } else { + UnwindBlock = new BasicBlock("UnifiedUnwindBlock", &F); + UnwindBlock->getInstList().push_back(new UnwindInst()); + for (std::vector<BasicBlock*>::iterator I = UnwindingBlocks.begin(), + E = UnwindingBlocks.end(); I != E; ++I) { + BasicBlock *BB = *I; + BB->getInstList().pop_back(); // Remove the return insn + BB->getInstList().push_back(new BranchInst(UnwindBlock)); + } + } + + // Now handle return blocks... if (ReturningBlocks.empty()) { - ExitNode = 0; + ReturnBlock = 0; return false; // No blocks return } else if (ReturningBlocks.size() == 1) { - ExitNode = ReturningBlocks.front(); // Already has a single return block + ReturnBlock = ReturningBlocks.front(); // Already has a single return block return false; } @@ -50,7 +75,7 @@ bool UnifyFunctionExitNodes::runOnFunction(Function &F) { // node (if the function returns a value), and convert all of the return // instructions into unconditional branches. // - BasicBlock *NewRetBlock = new BasicBlock("UnifiedExitNode", &F); + BasicBlock *NewRetBlock = new BasicBlock("UnifiedReturnBlock", &F); PHINode *PN = 0; if (F.getReturnType() != Type::VoidTy) { @@ -77,7 +102,6 @@ bool UnifyFunctionExitNodes::runOnFunction(Function &F) { BB->getInstList().pop_back(); // Remove the return insn BB->getInstList().push_back(new BranchInst(NewRetBlock)); } - ExitNode = NewRetBlock; - + ReturnBlock = NewRetBlock; return true; } |