From 22108fac63eac53d1a23b781a9963fab99700135 Mon Sep 17 00:00:00 2001 From: Misha Brukman Date: Fri, 23 Apr 2004 23:54:17 +0000 Subject: [PATCH] * Allow aggregating extracted function arguments (controlled by flag) * Commandline option (for now) controls that flag that is passed in git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13141 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Utils/CodeExtractor.cpp | 244 ++++++++++++++++++++----- 1 file changed, 198 insertions(+), 46 deletions(-) diff --git a/lib/Transforms/Utils/CodeExtractor.cpp b/lib/Transforms/Utils/CodeExtractor.cpp index f2af475c042..b16a71bb4db 100644 --- a/lib/Transforms/Utils/CodeExtractor.cpp +++ b/lib/Transforms/Utils/CodeExtractor.cpp @@ -23,22 +23,35 @@ #include "llvm/Analysis/LoopInfo.h" #include "llvm/Analysis/Verifier.h" #include "llvm/Transforms/Utils/BasicBlockUtils.h" +#include "Support/CommandLine.h" #include "Support/Debug.h" #include "Support/StringExtras.h" #include #include using namespace llvm; +// Provide a command-line option to aggregate function arguments into a struct +// for functions produced by the code extrator. This is useful when converting +// extracted functions to pthread-based code, as only one argument (void*) can +// be passed in to pthread_create(). +static cl::opt +AggregateArgsOpt("aggregate-extracted-args", cl::Hidden, + cl::desc("Aggregate arguments to code-extracted functions")); + namespace { class CodeExtractor { typedef std::vector Values; std::set BlocksToExtract; DominatorSet *DS; + bool AggregateArgs; public: - CodeExtractor(DominatorSet *ds = 0) : DS(ds) {} + CodeExtractor(DominatorSet *ds = 0, bool AggArgs = false) + : DS(ds), AggregateArgs(AggregateArgsOpt) {} Function *ExtractCodeRegion(const std::vector &code); + bool isEligible(const std::vector &code); + private: void findInputsOutputs(Values &inputs, Values &outputs, BasicBlock *newHeader, @@ -135,15 +148,22 @@ Function *CodeExtractor::constructFunction(const Values &inputs, for (Values::const_iterator I = outputs.begin(), E = outputs.end(); I != E; ++I) { DEBUG(std::cerr << "instr used in func: " << *I << "\n"); - paramTy.push_back(PointerType::get((*I)->getType())); + if (AggregateArgs) + paramTy.push_back((*I)->getType()); + else + paramTy.push_back(PointerType::get((*I)->getType())); } DEBUG(std::cerr << "Function type: " << retTy << " f("); - for (std::vector::iterator i = paramTy.begin(), - e = paramTy.end(); i != e; ++i) - DEBUG(std::cerr << *i << ", "); + DEBUG(for (std::vector::iterator i = paramTy.begin(), + e = paramTy.end(); i != e; ++i) std::cerr << *i << ", "); DEBUG(std::cerr << ")\n"); + if (AggregateArgs && (inputs.size() + outputs.size() > 0)) { + PointerType *StructPtr = PointerType::get(StructType::get(paramTy)); + paramTy.clear(); + paramTy.push_back(StructPtr); + } const FunctionType *funcType = FunctionType::get(retTy, paramTy, false); // Create the new function @@ -156,21 +176,36 @@ Function *CodeExtractor::constructFunction(const Values &inputs, Function::aiterator AI = newFunction->abegin(); // Rewrite all users of the inputs in the extracted region to use the - // arguments instead. - for (unsigned i = 0, e = inputs.size(); i != e; ++i, ++AI) { - AI->setName(inputs[i]->getName()); + // arguments (or appropriate addressing into struct) instead. + for (unsigned i = 0, e = inputs.size(); i != e; ++i) { + Value *RewriteVal; + if (AggregateArgs) { + std::vector Indices; + Indices.push_back(Constant::getNullValue(Type::UIntTy)); + Indices.push_back(ConstantUInt::get(Type::UIntTy, i)); + std::string GEPname = "gep_" + inputs[i]->getName(); + TerminatorInst *TI = newFunction->begin()->getTerminator(); + GetElementPtrInst *GEP = new GetElementPtrInst(AI, Indices, GEPname, TI); + RewriteVal = new LoadInst(GEP, "load" + GEPname, TI); + } else + RewriteVal = AI++; + std::vector Users(inputs[i]->use_begin(), inputs[i]->use_end()); for (std::vector::iterator use = Users.begin(), useE = Users.end(); use != useE; ++use) if (Instruction* inst = dyn_cast(*use)) if (BlocksToExtract.count(inst->getParent())) - inst->replaceUsesOfWith(inputs[i], AI); + inst->replaceUsesOfWith(inputs[i], RewriteVal); } - // Set names for all of the output arguments. - for (unsigned i = 0, e = outputs.size(); i != e; ++i, ++AI) - AI->setName(outputs[i]->getName()+".out"); - + // Set names for input and output arguments. + if (!AggregateArgs) { + AI = newFunction->abegin(); + for (unsigned i = 0, e = inputs.size(); i != e; ++i, ++AI) + AI->setName(inputs[i]->getName()); + for (unsigned i = 0, e = outputs.size(); i != e; ++i, ++AI) + AI->setName(outputs[i]->getName()+".out"); + } // Rewrite branches to basic blocks outside of the loop to new dummy blocks // within the new function. This must be done before we lose track of which @@ -207,23 +242,84 @@ CodeExtractor::emitCallAndSwitchStatement(Function *newFunction, BasicBlock *codeReplacer, Values &inputs, Values &outputs) { - // Emit a call to the new function, passing allocated memory for outputs and - // just plain inputs for non-scalars - std::vector params(inputs); - // Get an iterator to the first output argument. - Function::aiterator OutputArgBegin = newFunction->abegin(); - std::advance(OutputArgBegin, inputs.size()); + // Emit a call to the new function, passing in: + // *pointer to struct (if aggregating parameters), or + // plan inputs and allocated memory for outputs + std::vector params, StructValues, ReloadOutputs; - for (unsigned i = 0, e = outputs.size(); i != e; ++i) { - Value *Output = outputs[i]; - // Create allocas for scalar outputs - AllocaInst *alloca = - new AllocaInst(outputs[i]->getType(), 0, Output->getName()+".loc", + // Add inputs as params, or to be filled into the struct + for (Values::iterator i = inputs.begin(), e = inputs.end(); i != e; ++i) + if (AggregateArgs) + StructValues.push_back(*i); + else + params.push_back(*i); + + // Create allocas for the outputs + for (Values::iterator i = outputs.begin(), e = outputs.end(); i != e; ++i) { + if (AggregateArgs) { + StructValues.push_back(*i); + } else { + AllocaInst *alloca = + new AllocaInst((*i)->getType(), 0, (*i)->getName()+".loc", + codeReplacer->getParent()->begin()->begin()); + ReloadOutputs.push_back(alloca); + params.push_back(alloca); + } + } + + AllocaInst *Struct = 0; + if (AggregateArgs && (inputs.size() + outputs.size() > 0)) { + std::vector ArgTypes; + for (Values::iterator v = StructValues.begin(), + ve = StructValues.end(); v != ve; ++v) + ArgTypes.push_back((*v)->getType()); + + // Allocate a struct at the beginning of this function + Type *StructArgTy = StructType::get(ArgTypes); + Struct = + new AllocaInst(StructArgTy, 0, "structArg", codeReplacer->getParent()->begin()->begin()); - params.push_back(alloca); - - LoadInst *load = new LoadInst(alloca, Output->getName()+".reload"); + params.push_back(Struct); + + for (unsigned i = 0, e = inputs.size(); i != e; ++i) { + std::vector Indices; + Indices.push_back(Constant::getNullValue(Type::UIntTy)); + Indices.push_back(ConstantUInt::get(Type::UIntTy, i)); + GetElementPtrInst *GEP = + new GetElementPtrInst(Struct, Indices, + "gep_" + StructValues[i]->getName(), 0); + codeReplacer->getInstList().push_back(GEP); + StoreInst *SI = new StoreInst(StructValues[i], GEP); + codeReplacer->getInstList().push_back(SI); + } + } + + // Emit the call to the function + CallInst *call = new CallInst(newFunction, params, "targetBlock"); + codeReplacer->getInstList().push_back(call); + + Function::aiterator OutputArgBegin = newFunction->abegin(); + unsigned FirstOut = inputs.size(); + if (!AggregateArgs) + std::advance(OutputArgBegin, inputs.size()); + + // Reload the outputs passed in by reference + for (unsigned i = 0, e = outputs.size(); i != e; ++i) { + Value *Output = 0; + if (AggregateArgs) { + std::vector Indices; + Indices.push_back(Constant::getNullValue(Type::UIntTy)); + Indices.push_back(ConstantUInt::get(Type::UIntTy, FirstOut + i)); + GetElementPtrInst *GEP + = new GetElementPtrInst(Struct, Indices, + "gep_reload_" + outputs[i]->getName(), 0); + codeReplacer->getInstList().push_back(GEP); + Output = GEP; + } else { + Output = ReloadOutputs[i]; + } + LoadInst *load = new LoadInst(Output, outputs[i]->getName()+".reload"); codeReplacer->getInstList().push_back(load); std::vector Users(outputs[i]->use_begin(), outputs[i]->use_end()); for (unsigned u = 0, e = Users.size(); u != e; ++u) { @@ -233,9 +329,6 @@ CodeExtractor::emitCallAndSwitchStatement(Function *newFunction, } } - CallInst *call = new CallInst(newFunction, params, "targetBlock"); - codeReplacer->getInstList().push_front(call); - // Now we can emit a switch statement using the call as a value. SwitchInst *TheSwitch = new SwitchInst(call, codeReplacer, codeReplacer); @@ -268,13 +361,28 @@ CodeExtractor::emitCallAndSwitchStatement(Function *newFunction, TheSwitch->addCase(brVal, OldTarget); // Restore values just before we exit - // FIXME: Use a GetElementPtr to bunch the outputs in a struct Function::aiterator OAI = OutputArgBegin; - for (unsigned out = 0, e = outputs.size(); out != e; ++out, ++OAI) - if (!DS || - DS->dominates(cast(outputs[out])->getParent(), - TI->getParent())) - new StoreInst(outputs[out], OAI, NTRet); + for (unsigned out = 0, e = outputs.size(); out != e; ++out) { + // For an invoke, the normal destination is the only one that is + // dominated by the result of the invocation + BasicBlock *DefBlock = cast(outputs[out])->getParent(); + if (InvokeInst *Invoke = dyn_cast(outputs[out])) + DefBlock = Invoke->getNormalDest(); + if (!DS || DS->dominates(DefBlock, TI->getParent())) + if (AggregateArgs) { + std::vector Indices; + Indices.push_back(Constant::getNullValue(Type::UIntTy)); + Indices.push_back(ConstantUInt::get(Type::UIntTy,FirstOut+out)); + GetElementPtrInst *GEP = + new GetElementPtrInst(OAI, Indices, + "gep_" + outputs[out]->getName(), + NTRet); + new StoreInst(outputs[out], GEP, NTRet); + } else + new StoreInst(outputs[out], OAI, NTRet); + // Advance output iterator even if we don't emit a store + if (!AggregateArgs) ++OAI; + } } // rewrite the original branch instruction with this new target @@ -283,11 +391,39 @@ CodeExtractor::emitCallAndSwitchStatement(Function *newFunction, } // Now that we've done the deed, make the default destination of the switch - // instruction be one of the exit blocks of the region. + // instruction be a block with a call to abort() -- since this path should not + // be taken, this will abort sooner rather than later. if (TheSwitch->getNumSuccessors() > 1) { - // FIXME: this is broken w.r.t. PHI nodes, but the old code was more broken. - // This edge is not traversable. - TheSwitch->setSuccessor(0, TheSwitch->getSuccessor(1)); + Function *container = codeReplacer->getParent(); + BasicBlock *abortBB = new BasicBlock("abortBlock", container); + std::vector paramTypes; + FunctionType *abortTy = FunctionType::get(Type::VoidTy, paramTypes, false); + Function *abortFunc = + container->getParent()->getOrInsertFunction("abort", abortTy); + abortBB->getInstList().push_back(new CallInst(abortFunc)); + Function *ParentFunc = TheSwitch->getParent()->getParent(); + if (ParentFunc->getReturnType() == Type::VoidTy) + new ReturnInst(0, abortBB); + else + new ReturnInst(Constant::getNullValue(ParentFunc->getReturnType()), + abortBB); + TheSwitch->setSuccessor(0, abortBB); + } else { + // There is only 1 successor (the block containing the switch itself), which + // means that previously this was the last part of the function, and hence + // this should be rewritten as a `ret' + + // Check if the function should return a value + if (TheSwitch->getParent()->getParent()->getReturnType() != Type::VoidTy && + TheSwitch->getParent()->getParent()->getReturnType() == + TheSwitch->getCondition()->getType()) + // return what we have + new ReturnInst(TheSwitch->getCondition(), TheSwitch); + else + // just return + new ReturnInst(0, TheSwitch); + + TheSwitch->getParent()->getInstList().erase(TheSwitch); } } @@ -310,6 +446,9 @@ CodeExtractor::emitCallAndSwitchStatement(Function *newFunction, /// Function *CodeExtractor::ExtractCodeRegion(const std::vector &code) { + if (!isEligible(code)) + return 0; + // 1) Find inputs, outputs // 2) Construct new function // * Add allocas for defs, pass as args by reference @@ -393,24 +532,37 @@ Function *CodeExtractor::ExtractCodeRegion(const std::vector &code) return newFunction; } +bool CodeExtractor::isEligible(const std::vector &code) { + // Deny code region if it contains allocas + for (std::vector::const_iterator BB = code.begin(), e=code.end(); + BB != e; ++BB) + for (BasicBlock::const_iterator I = (*BB)->begin(), Ie = (*BB)->end(); + I != Ie; ++I) + if (isa(*I)) + return false; + return true; +} + + /// ExtractCodeRegion - slurp a sequence of basic blocks into a brand new /// function /// Function* llvm::ExtractCodeRegion(DominatorSet &DS, - const std::vector &code) { - return CodeExtractor(&DS).ExtractCodeRegion(code); + const std::vector &code, + bool AggregateArgs) { + return CodeExtractor(&DS, AggregateArgs).ExtractCodeRegion(code); } /// ExtractBasicBlock - slurp a natural loop into a brand new function /// -Function* llvm::ExtractLoop(DominatorSet &DS, Loop *L) { - return CodeExtractor(&DS).ExtractCodeRegion(L->getBlocks()); +Function* llvm::ExtractLoop(DominatorSet &DS, Loop *L, bool AggregateArgs) { + return CodeExtractor(&DS, AggregateArgs).ExtractCodeRegion(L->getBlocks()); } /// ExtractBasicBlock - slurp a basic block into a brand new function /// -Function* llvm::ExtractBasicBlock(BasicBlock *BB) { +Function* llvm::ExtractBasicBlock(BasicBlock *BB, bool AggregateArgs) { std::vector Blocks; Blocks.push_back(BB); - return CodeExtractor().ExtractCodeRegion(Blocks); + return CodeExtractor(0, AggregateArgs).ExtractCodeRegion(Blocks); }