void DebugDatabase::addIRInstructions(GenerateRTL *hw) { Function *F = hw->getFunction(); int instr_count = 0; for (Function::iterator b = F->begin(), be = F->end(); b != be; b++) { for (BasicBlock::iterator i = b->begin(), ie = b->end(); i != ie; i++) { instr_count++; bool isDummyDbgCall = false; if (isa<DbgDeclareInst>(i) || isa<DbgValueInst>(i)) isDummyDbgCall = true; if (i->hasMetadata()) { MDNode *n = i->getMetadata("dbg"); DILocation loc(n); int lineNumber = loc.getLineNumber(); int columnNumber = loc.getColumnNumber(); std::string filePath = loc.getDirectory().str() + "/" + loc.getFilename().str(); addIRInstruction(hw, i, instr_count, isDummyDbgCall, filePath, lineNumber, columnNumber); } else { addIRInstruction(hw, i, instr_count, isDummyDbgCall, "", 0, 0); } } } }
/// CloneAndPruneFunctionInto - This works exactly like CloneFunctionInto, /// except that it does some simple constant prop and DCE on the fly. The /// effect of this is to copy significantly less code in cases where (for /// example) a function call with constant arguments is inlined, and those /// constant arguments cause a significant amount of code in the callee to be /// dead. Since this doesn't produce an exact copy of the input, it can't be /// used for things like CloneFunction or CloneModule. void llvm::CloneAndPruneFunctionInto(Function *NewFunc, const Function *OldFunc, DenseMap<const Value*, Value*> &ValueMap, SmallVectorImpl<ReturnInst*> &Returns, const char *NameSuffix, ClonedCodeInfo *CodeInfo, const TargetData *TD, Instruction *TheCall) { assert(NameSuffix && "NameSuffix cannot be null!"); #ifndef NDEBUG for (Function::const_arg_iterator II = OldFunc->arg_begin(), E = OldFunc->arg_end(); II != E; ++II) assert(ValueMap.count(II) && "No mapping from source argument specified!"); #endif PruningFunctionCloner PFC(NewFunc, OldFunc, ValueMap, Returns, NameSuffix, CodeInfo, TD); // Clone the entry block, and anything recursively reachable from it. std::vector<const BasicBlock*> CloneWorklist; CloneWorklist.push_back(&OldFunc->getEntryBlock()); while (!CloneWorklist.empty()) { const BasicBlock *BB = CloneWorklist.back(); CloneWorklist.pop_back(); PFC.CloneBlock(BB, CloneWorklist); } // Loop over all of the basic blocks in the old function. If the block was // reachable, we have cloned it and the old block is now in the value map: // insert it into the new function in the right order. If not, ignore it. // // Defer PHI resolution until rest of function is resolved. SmallVector<const PHINode*, 16> PHIToResolve; for (Function::const_iterator BI = OldFunc->begin(), BE = OldFunc->end(); BI != BE; ++BI) { BasicBlock *NewBB = cast_or_null<BasicBlock>(ValueMap[BI]); if (NewBB == 0) continue; // Dead block. // Add the new block to the new function. NewFunc->getBasicBlockList().push_back(NewBB); // Loop over all of the instructions in the block, fixing up operand // references as we go. This uses ValueMap to do all the hard work. // BasicBlock::iterator I = NewBB->begin(); LLVMContext &Context = OldFunc->getContext(); unsigned DbgKind = Context.getMetadata().getMDKind("dbg"); MDNode *TheCallMD = NULL; SmallVector<Value *, 4> MDVs; if (TheCall && TheCall->hasMetadata()) TheCallMD = Context.getMetadata().getMD(DbgKind, TheCall); // Handle PHI nodes specially, as we have to remove references to dead // blocks. if (PHINode *PN = dyn_cast<PHINode>(I)) { // Skip over all PHI nodes, remembering them for later. BasicBlock::const_iterator OldI = BI->begin(); for (; (PN = dyn_cast<PHINode>(I)); ++I, ++OldI) { if (I->hasMetadata()) { if (TheCallMD) { if (MDNode *IMD = Context.getMetadata().getMD(DbgKind, I)) { MDNode *NewMD = UpdateInlinedAtInfo(IMD, TheCallMD, Context); Context.getMetadata().addMD(DbgKind, NewMD, I); } } else { // The cloned instruction has dbg info but the call instruction // does not have dbg info. Remove dbg info from cloned instruction. Context.getMetadata().removeMD(DbgKind, I); } } PHIToResolve.push_back(cast<PHINode>(OldI)); } } // Otherwise, remap the rest of the instructions normally. for (; I != NewBB->end(); ++I) { if (I->hasMetadata()) { if (TheCallMD) { if (MDNode *IMD = Context.getMetadata().getMD(DbgKind, I)) { MDNode *NewMD = UpdateInlinedAtInfo(IMD, TheCallMD, Context); Context.getMetadata().addMD(DbgKind, NewMD, I); } } else { // The cloned instruction has dbg info but the call instruction // does not have dbg info. Remove dbg info from cloned instruction. Context.getMetadata().removeMD(DbgKind, I); } } RemapInstruction(I, ValueMap); } } // Defer PHI resolution until rest of function is resolved, PHI resolution // requires the CFG to be up-to-date. for (unsigned phino = 0, e = PHIToResolve.size(); phino != e; ) { const PHINode *OPN = PHIToResolve[phino]; unsigned NumPreds = OPN->getNumIncomingValues(); const BasicBlock *OldBB = OPN->getParent(); BasicBlock *NewBB = cast<BasicBlock>(ValueMap[OldBB]); // Map operands for blocks that are live and remove operands for blocks // that are dead. for (; phino != PHIToResolve.size() && PHIToResolve[phino]->getParent() == OldBB; ++phino) { OPN = PHIToResolve[phino]; PHINode *PN = cast<PHINode>(ValueMap[OPN]); for (unsigned pred = 0, e = NumPreds; pred != e; ++pred) { if (BasicBlock *MappedBlock = cast_or_null<BasicBlock>(ValueMap[PN->getIncomingBlock(pred)])) { Value *InVal = MapValue(PN->getIncomingValue(pred), ValueMap); assert(InVal && "Unknown input value?"); PN->setIncomingValue(pred, InVal); PN->setIncomingBlock(pred, MappedBlock); } else { PN->removeIncomingValue(pred, false); --pred, --e; // Revisit the next entry. } } } // The loop above has removed PHI entries for those blocks that are dead // and has updated others. However, if a block is live (i.e. copied over) // but its terminator has been changed to not go to this block, then our // phi nodes will have invalid entries. Update the PHI nodes in this // case. PHINode *PN = cast<PHINode>(NewBB->begin()); NumPreds = std::distance(pred_begin(NewBB), pred_end(NewBB)); if (NumPreds != PN->getNumIncomingValues()) { assert(NumPreds < PN->getNumIncomingValues()); // Count how many times each predecessor comes to this block. std::map<BasicBlock*, unsigned> PredCount; for (pred_iterator PI = pred_begin(NewBB), E = pred_end(NewBB); PI != E; ++PI) --PredCount[*PI]; // Figure out how many entries to remove from each PHI. for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) ++PredCount[PN->getIncomingBlock(i)]; // At this point, the excess predecessor entries are positive in the // map. Loop over all of the PHIs and remove excess predecessor // entries. BasicBlock::iterator I = NewBB->begin(); for (; (PN = dyn_cast<PHINode>(I)); ++I) { for (std::map<BasicBlock*, unsigned>::iterator PCI =PredCount.begin(), E = PredCount.end(); PCI != E; ++PCI) { BasicBlock *Pred = PCI->first; for (unsigned NumToRemove = PCI->second; NumToRemove; --NumToRemove) PN->removeIncomingValue(Pred, false); } } } // If the loops above have made these phi nodes have 0 or 1 operand, // replace them with undef or the input value. We must do this for // correctness, because 0-operand phis are not valid. PN = cast<PHINode>(NewBB->begin()); if (PN->getNumIncomingValues() == 0) { BasicBlock::iterator I = NewBB->begin(); BasicBlock::const_iterator OldI = OldBB->begin(); while ((PN = dyn_cast<PHINode>(I++))) { Value *NV = UndefValue::get(PN->getType()); PN->replaceAllUsesWith(NV); assert(ValueMap[OldI] == PN && "ValueMap mismatch"); ValueMap[OldI] = NV; PN->eraseFromParent(); ++OldI; } } // NOTE: We cannot eliminate single entry phi nodes here, because of // ValueMap. Single entry phi nodes can have multiple ValueMap entries // pointing at them. Thus, deleting one would require scanning the ValueMap // to update any entries in it that would require that. This would be // really slow. } // Now that the inlined function body has been fully constructed, go through // and zap unconditional fall-through branches. This happen all the time when // specializing code: code specialization turns conditional branches into // uncond branches, and this code folds them. Function::iterator I = cast<BasicBlock>(ValueMap[&OldFunc->getEntryBlock()]); while (I != NewFunc->end()) { BranchInst *BI = dyn_cast<BranchInst>(I->getTerminator()); if (!BI || BI->isConditional()) { ++I; continue; } // Note that we can't eliminate uncond branches if the destination has // single-entry PHI nodes. Eliminating the single-entry phi nodes would // require scanning the ValueMap to update any entries that point to the phi // node. BasicBlock *Dest = BI->getSuccessor(0); if (!Dest->getSinglePredecessor() || isa<PHINode>(Dest->begin())) { ++I; continue; } // We know all single-entry PHI nodes in the inlined function have been // removed, so we just need to splice the blocks. BI->eraseFromParent(); // Move all the instructions in the succ to the pred. I->getInstList().splice(I->end(), Dest->getInstList()); // Make all PHI nodes that referred to Dest now refer to I as their source. Dest->replaceAllUsesWith(I); // Remove the dest block. Dest->eraseFromParent(); // Do not increment I, iteratively merge all things this block branches to. } }