diff options
| -rw-r--r-- | llvm/lib/Analysis/IPA/IPModRef.cpp | 60 |
1 files changed, 56 insertions, 4 deletions
diff --git a/llvm/lib/Analysis/IPA/IPModRef.cpp b/llvm/lib/Analysis/IPA/IPModRef.cpp index 6b7095bcabd..3631514b557 100644 --- a/llvm/lib/Analysis/IPA/IPModRef.cpp +++ b/llvm/lib/Analysis/IPA/IPModRef.cpp @@ -109,8 +109,11 @@ void FunctionModRefInfo::computeModRef(const Function &func) // // NOTE: Because this clones a dsgraph and returns it, the caller is responsible // for deleting the returned graph! +// NOTE: This method may return a null pointer if it is unable to determine the +// requested information (because the call site calls an external +// function or we cannot determine the complete set of functions invoked). // -DSGraph *FunctionModRefInfo::ResolveCallSiteModRefInfo(const CallInst &CI, +DSGraph *FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI, std::map<const DSNode*, DSNodeHandle> &NodeMap) { // Step #1: Clone the top-down graph... @@ -126,8 +129,46 @@ DSGraph *FunctionModRefInfo::ResolveCallSiteModRefInfo(const CallInst &CI, // Step #2: Clear Mod/Ref information... Result->maskNodeTypes(~(DSNode::Modified | DSNode::Read)); + // Step #3: clone the bottom up graphs for the callees into the caller graph + if (const Function *F = CI.getCalledFunction()) { + if (F->isExternal()) { + delete Result; + return 0; // We cannot compute Mod/Ref info for this callsite... + } - + // Build up a DSCallSite for our invocation point here... + + // If the call returns a value, make sure to merge the nodes... + DSNodeHandle RetVal; + if (DS::isPointerType(CI.getType())) + RetVal = Result->getNodeForValue(&CI); + + // Populate the arguments list... + std::vector<DSNodeHandle> Args; + for (unsigned i = 1, e = CI.getNumOperands(); i != e; ++i) + if (DS::isPointerType(CI.getOperand(i)->getType())) + Args.push_back(Result->getNodeForValue(CI.getOperand(i))); + + // Build the call site... + DSCallSite CS(CI, RetVal, 0, Args); + + // Perform the merging now of the graph for the callee, which will come with + // mod/ref bits set... + Result->mergeInGraph(CS, IPModRefObj.getBUDSGraph(*F), + DSGraph::StripAllocaBit); + + } else { + std::cerr << "IP Mod/Ref indirect call not implemented yet: " + << "Being conservative\n"; + delete Result; + return 0; + } + + // Remove trivial dead nodes... don't aggressively prune graph though... the + // graph is short lived anyway. + Result->removeTriviallyDeadNodes(false); + + // Step #4: Return the clone + the mapping (by ref) return Result; } @@ -145,7 +186,11 @@ FunctionModRefInfo::computeModRef(const CallInst& callInst) // Get a copy of the graph for the callee with the callee inlined std::map<const DSNode*, DSNodeHandle> NodeMap; - DSGraph* csgp = ResolveCallSiteModRefInfo(callInst, NodeMap); + DSGraph* csgp = + ResolveCallSiteModRefInfo(const_cast<CallInst&>(callInst), NodeMap); + + assert(csgp && "FIXME: Cannot handle case where call site mod/ref info" + " is not available yet!"); // For all nodes in the graph, extract the mod/ref information const std::vector<DSNode*>& csgNodes = csgp->getNodes(); @@ -209,7 +254,6 @@ void IPModRef::releaseMemory() funcToModRefInfoMap.clear(); } - // Run the "interprocedural" pass on each function. This needs to do // NO real interprocedural work because all that has been done the // data structure analysis. @@ -240,6 +284,14 @@ FunctionModRefInfo& IPModRef::getFuncInfo(const Function& func, return *funcInfo; } +/// getBUDSGraph - This method returns the BU data structure graph for F through +/// the use of the BUDataStructures object. +/// +const DSGraph &IPModRef::getBUDSGraph(const Function &F) { + return getAnalysis<BUDataStructures>().getDSGraph(F); +} + + // getAnalysisUsage - This pass requires top-down data structure graphs. // It modifies nothing. // |
