diff options
| -rw-r--r-- | include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h | 14 | ||||
| -rw-r--r-- | lib/Transforms/Utils/UnifyFunctionExitNodes.cpp | 19 |
2 files changed, 21 insertions, 12 deletions
diff --git a/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h b/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h index 0939468..64dc03c 100644 --- a/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h +++ b/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h @@ -10,7 +10,6 @@ #define LLVM_XFORMS_UNIFY_METHOD_EXIT_NODES_H #include "llvm/Pass.h" -#include "llvm/Analysis/SimplifyCFG.h" // FIXME!! struct UnifyMethodExitNodes : public MethodPass { BasicBlock *ExitNode; @@ -18,10 +17,17 @@ public: static AnalysisID ID; // Pass ID UnifyMethodExitNodes(AnalysisID id) : ExitNode(0) { assert(ID == id); } - virtual bool runOnMethod(Method *M) { - ExitNode = cfg::UnifyAllExitNodes(M); + // UnifyAllExitNodes - Unify all exit nodes of the CFG by creating a new + // BasicBlock, and converting all returns to unconditional branches to this + // new basic block. The singular exit node is returned in ExitNode. + // + // If there are no return stmts in the Method, a null pointer is returned. + // + static bool doit(Method *M, BasicBlock *&ExitNode); + - return true; // FIXME: This should return a correct code!!! + virtual bool runOnMethod(Method *M) { + return doit(M, ExitNode); } BasicBlock *getExitNode() const { return ExitNode; } diff --git a/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp b/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp index 4716e7e..15e37e3 100644 --- a/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp +++ b/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp @@ -5,7 +5,6 @@ // //===----------------------------------------------------------------------===// -#include "llvm/Analysis/SimplifyCFG.h" #include "llvm/Transforms/UnifyMethodExitNodes.h" #include "llvm/BasicBlock.h" #include "llvm/Method.h" @@ -23,7 +22,7 @@ AnalysisID UnifyMethodExitNodes::ID(AnalysisID::create<UnifyMethodExitNodes>()); // // If there are no return stmts in the Method, a null pointer is returned. // -BasicBlock *cfg::UnifyAllExitNodes(Method *M) { +bool UnifyMethodExitNodes::doit(Method *M, BasicBlock *&ExitNode) { vector<BasicBlock*> ReturningBlocks; // Loop over all of the blocks in a method, tracking all of the blocks that @@ -33,16 +32,19 @@ BasicBlock *cfg::UnifyAllExitNodes(Method *M) { if ((*I)->getTerminator()->getOpcode() == Instruction::Ret) ReturningBlocks.push_back(*I); - if (ReturningBlocks.size() == 0) - return 0; // No blocks return - else if (ReturningBlocks.size() == 1) - return ReturningBlocks.front(); // Already has a single return block + if (ReturningBlocks.size() == 0) { + ExitNode = 0; + return false; // No blocks return + } else if (ReturningBlocks.size() == 1) { + ExitNode = ReturningBlocks.front(); // Already has a single return block + return false; + } // Otherwise, we need to insert a new basic block into the method, add a PHI // node (if the function returns a value), and convert all of the return // instructions into unconditional branches. // - BasicBlock *NewRetBlock = new BasicBlock("", M); + BasicBlock *NewRetBlock = new BasicBlock("UnifiedExitNode", M); if (M->getReturnType() != Type::VoidTy) { // If the method doesn't return void... add a PHI node to the block... @@ -70,5 +72,6 @@ BasicBlock *cfg::UnifyAllExitNodes(Method *M) { delete (*I)->getInstList().pop_back(); // Remove the return insn (*I)->getInstList().push_back(new BranchInst(NewRetBlock)); } - return NewRetBlock; + ExitNode = NewRetBlock; + return true; } |