Esempio n. 1
0
/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into
/// an invoke, we have to turn all of the calls that can throw into
/// invokes.  This function analyze BB to see if there are any calls, and if so,
/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI
/// nodes in that block with the values specified in InvokeDestPHIValues.
///
/// Returns true to indicate that the next block should be skipped.
static bool HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
                                                   InvokeInliningInfo &Invoke) {
  LandingPadInst *LPI = Invoke.getLandingPadInst();

  for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
    Instruction *I = BBI++;

    if (LandingPadInst *L = dyn_cast<LandingPadInst>(I)) {
      unsigned NumClauses = LPI->getNumClauses();
      L->reserveClauses(NumClauses);
      for (unsigned i = 0; i != NumClauses; ++i)
        L->addClause(LPI->getClause(i));
    }

    // We only need to check for function calls: inlined invoke
    // instructions require no special handling.
    CallInst *CI = dyn_cast<CallInst>(I);

    // If this call cannot unwind, don't convert it to an invoke.
    if (!CI || CI->doesNotThrow())
      continue;

    // Convert this function call into an invoke instruction.  First, split the
    // basic block.
    BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");

    // Delete the unconditional branch inserted by splitBasicBlock
    BB->getInstList().pop_back();

    // Create the new invoke instruction.
    ImmutableCallSite CS(CI);
    SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end());
    InvokeInst *II = InvokeInst::Create(CI->getCalledValue(), Split,
                                        Invoke.getOuterResumeDest(),
                                        InvokeArgs, CI->getName(), BB);
    II->setCallingConv(CI->getCallingConv());
    II->setAttributes(CI->getAttributes());
    
    // Make sure that anything using the call now uses the invoke!  This also
    // updates the CallGraph if present, because it uses a WeakVH.
    CI->replaceAllUsesWith(II);

    // Delete the original call
    Split->getInstList().pop_front();

    // Update any PHI nodes in the exceptional block to indicate that there is
    // now a new entry in them.
    Invoke.addIncomingPHIValuesFor(BB);
    return false;
  }

  return false;
}
Esempio n. 2
0
/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into
/// an invoke, we have to turn all of the calls that can throw into
/// invokes.  This function analyze BB to see if there are any calls, and if so,
/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI
/// nodes in that block with the values specified in InvokeDestPHIValues.
///
static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
                                                   BasicBlock *InvokeDest,
                           const SmallVectorImpl<Value*> &InvokeDestPHIValues) {
  for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
    Instruction *I = BBI++;
    
    // We only need to check for function calls: inlined invoke
    // instructions require no special handling.
    CallInst *CI = dyn_cast<CallInst>(I);
    if (CI == 0) continue;
    
    // If this call cannot unwind, don't convert it to an invoke.
    if (CI->doesNotThrow())
      continue;
    
    // Convert this function call into an invoke instruction.
    // First, split the basic block.
    BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");
    
    // Next, create the new invoke instruction, inserting it at the end
    // of the old basic block.
    ImmutableCallSite CS(CI);
    SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end());
    InvokeInst *II =
      InvokeInst::Create(CI->getCalledValue(), Split, InvokeDest,
                         InvokeArgs.begin(), InvokeArgs.end(),
                         CI->getName(), BB->getTerminator());
    II->setCallingConv(CI->getCallingConv());
    II->setAttributes(CI->getAttributes());
    
    // Make sure that anything using the call now uses the invoke!  This also
    // updates the CallGraph if present, because it uses a WeakVH.
    CI->replaceAllUsesWith(II);
    
    // Delete the unconditional branch inserted by splitBasicBlock
    BB->getInstList().pop_back();
    Split->getInstList().pop_front();  // Delete the original call
    
    // Update any PHI nodes in the exceptional block to indicate that
    // there is now a new entry in them.
    unsigned i = 0;
    for (BasicBlock::iterator I = InvokeDest->begin();
         isa<PHINode>(I); ++I, ++i)
      cast<PHINode>(I)->addIncoming(InvokeDestPHIValues[i], BB);
    
    // This basic block is now complete, the caller will continue scanning the
    // next one.
    return;
  }
}
Esempio n. 3
0
// visitCallInst - This converts all LLVM call instructions into invoke
// instructions. The except part of the invoke goes to the "LongJmpBlkPre"
// that grabs the exception and proceeds to determine if it's a longjmp
// exception or not.
void LowerSetJmp::visitCallInst(CallInst& CI)
{
  if (CI.getCalledFunction())
    if (!IsTransformableFunction(CI.getCalledFunction()->getName()) ||
        CI.getCalledFunction()->isIntrinsic()) return;

  BasicBlock* OldBB = CI.getParent();

  // If not reachable from a setjmp call, don't transform.
  if (!DFSBlocks.count(OldBB)) return;

  BasicBlock* NewBB = OldBB->splitBasicBlock(CI);
  assert(NewBB && "Couldn't split BB of \"call\" instruction!!");
  DFSBlocks.insert(NewBB);
  NewBB->setName("Call2Invoke");

  Function* Func = OldBB->getParent();

  // Construct the new "invoke" instruction.
  TerminatorInst* Term = OldBB->getTerminator();
  CallSite CS(&CI);
  std::vector<Value*> Params(CS.arg_begin(), CS.arg_end());
  InvokeInst* II =
    InvokeInst::Create(CI.getCalledValue(), NewBB, PrelimBBMap[Func],
                       Params.begin(), Params.end(), CI.getName(), Term);
  II->setCallingConv(CI.getCallingConv());
  II->setAttributes(CI.getAttributes());

  // Replace the old call inst with the invoke inst and remove the call.
  CI.replaceAllUsesWith(II);
  CI.eraseFromParent();

  // The old terminator is useless now that we have the invoke inst.
  Term->eraseFromParent();
  ++CallsTransformed;
}
Esempio n. 4
0
/// Replaces the given call site (Call or Invoke) with a gc.statepoint
/// intrinsic with an empty deoptimization arguments list.  This does
/// NOT do explicit relocation for GC support.
static Value *ReplaceWithStatepoint(const CallSite &CS /* to replace */) {
  assert(CS.getInstruction()->getModule() && "must be set");

  // TODO: technically, a pass is not allowed to get functions from within a
  // function pass since it might trigger a new function addition.  Refactor
  // this logic out to the initialization of the pass.  Doesn't appear to
  // matter in practice.

  // Then go ahead and use the builder do actually do the inserts.  We insert
  // immediately before the previous instruction under the assumption that all
  // arguments will be available here.  We can't insert afterwards since we may
  // be replacing a terminator.
  IRBuilder<> Builder(CS.getInstruction());

  // Note: The gc args are not filled in at this time, that's handled by
  // RewriteStatepointsForGC (which is currently under review).

  // Create the statepoint given all the arguments
  Instruction *Token = nullptr;

  uint64_t ID;
  uint32_t NumPatchBytes;

  AttributeSet OriginalAttrs = CS.getAttributes();
  Attribute AttrID =
      OriginalAttrs.getAttribute(AttributeSet::FunctionIndex, "statepoint-id");
  Attribute AttrNumPatchBytes = OriginalAttrs.getAttribute(
      AttributeSet::FunctionIndex, "statepoint-num-patch-bytes");

  AttrBuilder AttrsToRemove;
  bool HasID = AttrID.isStringAttribute() &&
               !AttrID.getValueAsString().getAsInteger(10, ID);

  if (HasID)
    AttrsToRemove.addAttribute("statepoint-id");
  else
    ID = 0xABCDEF00;

  bool HasNumPatchBytes =
      AttrNumPatchBytes.isStringAttribute() &&
      !AttrNumPatchBytes.getValueAsString().getAsInteger(10, NumPatchBytes);

  if (HasNumPatchBytes)
    AttrsToRemove.addAttribute("statepoint-num-patch-bytes");
  else
    NumPatchBytes = 0;

  OriginalAttrs = OriginalAttrs.removeAttributes(
      CS.getInstruction()->getContext(), AttributeSet::FunctionIndex,
      AttrsToRemove);

  if (CS.isCall()) {
    CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
    CallInst *Call = Builder.CreateGCStatepointCall(
        ID, NumPatchBytes, CS.getCalledValue(),
        makeArrayRef(CS.arg_begin(), CS.arg_end()), None, None,
        "safepoint_token");
    Call->setTailCall(ToReplace->isTailCall());
    Call->setCallingConv(ToReplace->getCallingConv());

    // In case if we can handle this set of attributes - set up function
    // attributes directly on statepoint and return attributes later for
    // gc_result intrinsic.
    Call->setAttributes(OriginalAttrs.getFnAttributes());

    Token = Call;

    // Put the following gc_result and gc_relocate calls immediately after
    // the old call (which we're about to delete).
    assert(ToReplace->getNextNode() && "not a terminator, must have next");
    Builder.SetInsertPoint(ToReplace->getNextNode());
    Builder.SetCurrentDebugLocation(ToReplace->getNextNode()->getDebugLoc());
  } else if (CS.isInvoke()) {
    InvokeInst *ToReplace = cast<InvokeInst>(CS.getInstruction());

    // Insert the new invoke into the old block.  We'll remove the old one in a
    // moment at which point this will become the new terminator for the
    // original block.
    Builder.SetInsertPoint(ToReplace->getParent());
    InvokeInst *Invoke = Builder.CreateGCStatepointInvoke(
        ID, NumPatchBytes, CS.getCalledValue(), ToReplace->getNormalDest(),
        ToReplace->getUnwindDest(), makeArrayRef(CS.arg_begin(), CS.arg_end()),
        None, None, "safepoint_token");

    Invoke->setCallingConv(ToReplace->getCallingConv());

    // In case if we can handle this set of attributes - set up function
    // attributes directly on statepoint and return attributes later for
    // gc_result intrinsic.
    Invoke->setAttributes(OriginalAttrs.getFnAttributes());

    Token = Invoke;

    // We'll insert the gc.result into the normal block
    BasicBlock *NormalDest = ToReplace->getNormalDest();
    // Can not insert gc.result in case of phi nodes preset.
    // Should have removed this cases prior to running this function
    assert(!isa<PHINode>(NormalDest->begin()));
    Instruction *IP = &*(NormalDest->getFirstInsertionPt());
    Builder.SetInsertPoint(IP);
  } else {
    llvm_unreachable("unexpect type of CallSite");
  }
  assert(Token);

  // Handle the return value of the original call - update all uses to use a
  // gc_result hanging off the statepoint node we just inserted

  // Only add the gc_result iff there is actually a used result
  if (!CS.getType()->isVoidTy() && !CS.getInstruction()->use_empty()) {
    std::string TakenName =
        CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "";
    CallInst *GCResult = Builder.CreateGCResult(Token, CS.getType(), TakenName);
    GCResult->setAttributes(OriginalAttrs.getRetAttributes());
    return GCResult;
  } else {
    // No return value for the call.
    return nullptr;
  }
}
Esempio n. 5
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/// HandleInlinedInvoke - If we inlined an invoke site, we need to convert calls
/// in the body of the inlined function into invokes and turn unwind
/// instructions into branches to the invoke unwind dest.
///
/// II is the invoke instruction being inlined.  FirstNewBlock is the first
/// block of the inlined code (the last block is the end of the function),
/// and InlineCodeInfo is information about the code that got inlined.
static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
                                ClonedCodeInfo &InlinedCodeInfo) {
  BasicBlock *InvokeDest = II->getUnwindDest();
  std::vector<Value*> InvokeDestPHIValues;

  // If there are PHI nodes in the unwind destination block, we need to
  // keep track of which values came into them from this invoke, then remove
  // the entry for this block.
  BasicBlock *InvokeBlock = II->getParent();
  for (BasicBlock::iterator I = InvokeDest->begin(); isa<PHINode>(I); ++I) {
    PHINode *PN = cast<PHINode>(I);
    // Save the value to use for this edge.
    InvokeDestPHIValues.push_back(PN->getIncomingValueForBlock(InvokeBlock));
  }

  Function *Caller = FirstNewBlock->getParent();

  // The inlined code is currently at the end of the function, scan from the
  // start of the inlined code to its end, checking for stuff we need to
  // rewrite.
  if (InlinedCodeInfo.ContainsCalls || InlinedCodeInfo.ContainsUnwinds) {
    for (Function::iterator BB = FirstNewBlock, E = Caller->end();
         BB != E; ++BB) {
      if (InlinedCodeInfo.ContainsCalls) {
        for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ){
          Instruction *I = BBI++;

          // We only need to check for function calls: inlined invoke
          // instructions require no special handling.
          if (!isa<CallInst>(I)) continue;
          CallInst *CI = cast<CallInst>(I);

          // If this call cannot unwind, don't convert it to an invoke.
          if (CI->doesNotThrow())
            continue;

          // Convert this function call into an invoke instruction.
          // First, split the basic block.
          BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");

          // Next, create the new invoke instruction, inserting it at the end
          // of the old basic block.
          SmallVector<Value*, 8> InvokeArgs(CI->op_begin()+1, CI->op_end());
          InvokeInst *II =
            InvokeInst::Create(CI->getCalledValue(), Split, InvokeDest,
                               InvokeArgs.begin(), InvokeArgs.end(),
                               CI->getName(), BB->getTerminator());
          II->setCallingConv(CI->getCallingConv());
          II->setAttributes(CI->getAttributes());

          // Make sure that anything using the call now uses the invoke!
          CI->replaceAllUsesWith(II);

          // Delete the unconditional branch inserted by splitBasicBlock
          BB->getInstList().pop_back();
          Split->getInstList().pop_front();  // Delete the original call

          // Update any PHI nodes in the exceptional block to indicate that
          // there is now a new entry in them.
          unsigned i = 0;
          for (BasicBlock::iterator I = InvokeDest->begin();
               isa<PHINode>(I); ++I, ++i) {
            PHINode *PN = cast<PHINode>(I);
            PN->addIncoming(InvokeDestPHIValues[i], BB);
          }

          // This basic block is now complete, start scanning the next one.
          break;
        }
      }

      if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
        // An UnwindInst requires special handling when it gets inlined into an
        // invoke site.  Once this happens, we know that the unwind would cause
        // a control transfer to the invoke exception destination, so we can
        // transform it into a direct branch to the exception destination.
        BranchInst::Create(InvokeDest, UI);

        // Delete the unwind instruction!
        UI->eraseFromParent();

        // Update any PHI nodes in the exceptional block to indicate that
        // there is now a new entry in them.
        unsigned i = 0;
        for (BasicBlock::iterator I = InvokeDest->begin();
             isa<PHINode>(I); ++I, ++i) {
          PHINode *PN = cast<PHINode>(I);
          PN->addIncoming(InvokeDestPHIValues[i], BB);
        }
      }
    }
  }

  // Now that everything is happy, we have one final detail.  The PHI nodes in
  // the exception destination block still have entries due to the original
  // invoke instruction.  Eliminate these entries (which might even delete the
  // PHI node) now.
  InvokeDest->removePredecessor(II->getParent());
}
Esempio n. 6
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//
// Method: runOnModule()
//
// Description:
//  Entry point for this LLVM pass.
//  Clone functions that take GEPs as arguments
//
// Inputs:
//  M - A reference to the LLVM module to transform
//
// Outputs:
//  M - The transformed LLVM module.
//
// Return value:
//  true  - The module was modified.
//  false - The module was not modified.
//
bool GEPExprArgs::runOnModule(Module& M) {
  bool changed;
  do {
    changed = false;
    for (Module::iterator F = M.begin(); F != M.end(); ++F){
      for (Function::iterator B = F->begin(), FE = F->end(); B != FE; ++B) {
        for (BasicBlock::iterator I = B->begin(), BE = B->end(); I != BE;) {
          CallInst *CI = dyn_cast<CallInst>(I++);
          if(!CI)
            continue;

          if(CI->hasByValArgument())
            continue;
          // if the GEP calls a function, that is externally defined,
          // or might be changed, ignore this call site.
          Function *F = CI->getCalledFunction();

          if (!F || (F->isDeclaration() || F->mayBeOverridden())) 
            continue;
          if(F->hasStructRetAttr())
            continue;
          if(F->isVarArg())
            continue;

          // find the argument we must replace
          Function::arg_iterator ai = F->arg_begin(), ae = F->arg_end();
          unsigned argNum = 1;
          for(; argNum < CI->getNumOperands();argNum++, ++ai) {
            if(ai->use_empty())
              continue;
            if (isa<GEPOperator>(CI->getOperand(argNum)))
              break;
          }

          // if no argument was a GEP operator to be changed 
          if(ai == ae)
            continue;

          GEPOperator *GEP = dyn_cast<GEPOperator>(CI->getOperand(argNum));
          if(!GEP->hasAllConstantIndices())
            continue;

          // Construct the new Type
          // Appends the struct Type at the beginning
          std::vector<Type*>TP;
          TP.push_back(GEP->getPointerOperand()->getType());
          for(unsigned c = 1; c < CI->getNumOperands();c++) {
            TP.push_back(CI->getOperand(c)->getType());
          }

          //return type is same as that of original instruction
          FunctionType *NewFTy = FunctionType::get(CI->getType(), TP, false);
          Function *NewF;
          numSimplified++;
          if(numSimplified > 800) 
            return true;

          NewF = Function::Create(NewFTy,
                                  GlobalValue::InternalLinkage,
                                  F->getName().str() + ".TEST",
                                  &M);

          Function::arg_iterator NI = NewF->arg_begin();
          NI->setName("GEParg");
          ++NI;

          ValueToValueMapTy ValueMap;

          for (Function::arg_iterator II = F->arg_begin(); NI != NewF->arg_end(); ++II, ++NI) {
            ValueMap[II] = NI;
            NI->setName(II->getName());
            NI->addAttr(F->getAttributes().getParamAttributes(II->getArgNo() + 1));
          }
          NewF->setAttributes(NewF->getAttributes().addAttr(
              0, F->getAttributes().getRetAttributes()));
          // Perform the cloning.
          SmallVector<ReturnInst*,100> Returns;
          CloneFunctionInto(NewF, F, ValueMap, false, Returns);
          std::vector<Value*> fargs;
          for(Function::arg_iterator ai = NewF->arg_begin(), 
              ae= NewF->arg_end(); ai != ae; ++ai) {
            fargs.push_back(ai);
          }

          NewF->setAttributes(NewF->getAttributes().addAttr(
              ~0, F->getAttributes().getFnAttributes()));
          //Get the point to insert the GEP instr.
          SmallVector<Value*, 8> Ops(CI->op_begin()+1, CI->op_end());
          Instruction *InsertPoint;
          for (BasicBlock::iterator insrt = NewF->front().begin(); 
               isa<AllocaInst>(InsertPoint = insrt); ++insrt) {;}

          NI = NewF->arg_begin();
          SmallVector<Value*, 8> Indices;
          Indices.append(GEP->op_begin()+1, GEP->op_end());
          GetElementPtrInst *GEP_new = GetElementPtrInst::Create(cast<Value>(NI),
                                                                 Indices, 
                                                                 "", InsertPoint);
          fargs.at(argNum)->replaceAllUsesWith(GEP_new);
          unsigned j = argNum + 1;
          for(; j < CI->getNumOperands();j++) {
            if(CI->getOperand(j) == GEP)
              fargs.at(j)->replaceAllUsesWith(GEP_new);
          }

          SmallVector<AttributeWithIndex, 8> AttributesVec;

          // Get the initial attributes of the call
          AttrListPtr CallPAL = CI->getAttributes();
          Attributes RAttrs = CallPAL.getRetAttributes();
          Attributes FnAttrs = CallPAL.getFnAttributes();
          if (RAttrs)
            AttributesVec.push_back(AttributeWithIndex::get(0, RAttrs));

          SmallVector<Value*, 8> Args;
          Args.push_back(GEP->getPointerOperand());
          for(unsigned j =1;j<CI->getNumOperands();j++) {
            Args.push_back(CI->getOperand(j));
            // position in the AttributesVec
            if (Attributes Attrs = CallPAL.getParamAttributes(j))
              AttributesVec.push_back(AttributeWithIndex::get(Args.size(), Attrs));
          }
          // Create the new attributes vec.
          if (FnAttrs != Attribute::None)
            AttributesVec.push_back(AttributeWithIndex::get(~0, FnAttrs));

          AttrListPtr NewCallPAL = AttrListPtr::get(AttributesVec.begin(),
                                                    AttributesVec.end());

          CallInst *CallI = CallInst::Create(NewF,Args,"", CI);
          CallI->setCallingConv(CI->getCallingConv());
          CallI->setAttributes(NewCallPAL);
          CI->replaceAllUsesWith(CallI);
          CI->eraseFromParent();
          changed = true;
        }
      }
    }
  } while(changed);
  return true;
}
/// Replaces the given call site (Call or Invoke) with a gc.statepoint
/// intrinsic with an empty deoptimization arguments list.  This does
/// NOT do explicit relocation for GC support.
static Value *ReplaceWithStatepoint(const CallSite &CS, /* to replace */
                                    Pass *P) {
  BasicBlock *BB = CS.getInstruction()->getParent();
  Function *F = BB->getParent();
  Module *M = F->getParent();
  assert(M && "must be set");

  // TODO: technically, a pass is not allowed to get functions from within a
  // function pass since it might trigger a new function addition.  Refactor
  // this logic out to the initialization of the pass.  Doesn't appear to
  // matter in practice.

  // Fill in the one generic type'd argument (the function is also vararg)
  std::vector<Type *> argTypes;
  argTypes.push_back(CS.getCalledValue()->getType());

  Function *gc_statepoint_decl = Intrinsic::getDeclaration(
      M, Intrinsic::experimental_gc_statepoint, argTypes);

  // Then go ahead and use the builder do actually do the inserts.  We insert
  // immediately before the previous instruction under the assumption that all
  // arguments will be available here.  We can't insert afterwards since we may
  // be replacing a terminator.
  Instruction *insertBefore = CS.getInstruction();
  IRBuilder<> Builder(insertBefore);
  // First, create the statepoint (with all live ptrs as arguments).
  std::vector<llvm::Value *> args;
  // target, #args, unused, args
  Value *Target = CS.getCalledValue();
  args.push_back(Target);
  int callArgSize = CS.arg_size();
  args.push_back(
      ConstantInt::get(Type::getInt32Ty(M->getContext()), callArgSize));
  // TODO: add a 'Needs GC-rewrite' later flag
  args.push_back(ConstantInt::get(Type::getInt32Ty(M->getContext()), 0));

  // Copy all the arguments of the original call
  args.insert(args.end(), CS.arg_begin(), CS.arg_end());

  // Create the statepoint given all the arguments
  Instruction *token = nullptr;
  AttributeSet return_attributes;
  if (CS.isCall()) {
    CallInst *toReplace = cast<CallInst>(CS.getInstruction());
    CallInst *call =
        Builder.CreateCall(gc_statepoint_decl, args, "safepoint_token");
    call->setTailCall(toReplace->isTailCall());
    call->setCallingConv(toReplace->getCallingConv());

    // Before we have to worry about GC semantics, all attributes are legal
    AttributeSet new_attrs = toReplace->getAttributes();
    // In case if we can handle this set of sttributes - set up function attrs
    // directly on statepoint and return attrs later for gc_result intrinsic.
    call->setAttributes(new_attrs.getFnAttributes());
    return_attributes = new_attrs.getRetAttributes();
    // TODO: handle param attributes

    token = call;

    // Put the following gc_result and gc_relocate calls immediately after the
    // the old call (which we're about to delete)
    BasicBlock::iterator next(toReplace);
    assert(BB->end() != next && "not a terminator, must have next");
    next++;
    Instruction *IP = &*(next);
    Builder.SetInsertPoint(IP);
    Builder.SetCurrentDebugLocation(IP->getDebugLoc());

  } else if (CS.isInvoke()) {
    InvokeInst *toReplace = cast<InvokeInst>(CS.getInstruction());

    // Insert the new invoke into the old block.  We'll remove the old one in a
    // moment at which point this will become the new terminator for the
    // original block.
    InvokeInst *invoke = InvokeInst::Create(
        gc_statepoint_decl, toReplace->getNormalDest(),
        toReplace->getUnwindDest(), args, "", toReplace->getParent());
    invoke->setCallingConv(toReplace->getCallingConv());

    // Currently we will fail on parameter attributes and on certain
    // function attributes.
    AttributeSet new_attrs = toReplace->getAttributes();
    // In case if we can handle this set of sttributes - set up function attrs
    // directly on statepoint and return attrs later for gc_result intrinsic.
    invoke->setAttributes(new_attrs.getFnAttributes());
    return_attributes = new_attrs.getRetAttributes();

    token = invoke;

    // We'll insert the gc.result into the normal block
    BasicBlock *normalDest = normalizeBBForInvokeSafepoint(
        toReplace->getNormalDest(), invoke->getParent());
    Instruction *IP = &*(normalDest->getFirstInsertionPt());
    Builder.SetInsertPoint(IP);
  } else {
    llvm_unreachable("unexpect type of CallSite");
  }
  assert(token);

  // Handle the return value of the original call - update all uses to use a
  // gc_result hanging off the statepoint node we just inserted

  // Only add the gc_result iff there is actually a used result
  if (!CS.getType()->isVoidTy() && !CS.getInstruction()->use_empty()) {
    Instruction *gc_result = nullptr;
    std::vector<Type *> types;     // one per 'any' type
    types.push_back(CS.getType()); // result type
    auto get_gc_result_id = [&](Type &Ty) {
      if (Ty.isIntegerTy()) {
        return Intrinsic::experimental_gc_result_int;
      } else if (Ty.isFloatingPointTy()) {
        return Intrinsic::experimental_gc_result_float;
      } else if (Ty.isPointerTy()) {
        return Intrinsic::experimental_gc_result_ptr;
      } else {
        llvm_unreachable("non java type encountered");
      }
    };
    Intrinsic::ID Id = get_gc_result_id(*CS.getType());
    Value *gc_result_func = Intrinsic::getDeclaration(M, Id, types);

    std::vector<Value *> args;
    args.push_back(token);
    gc_result = Builder.CreateCall(
        gc_result_func, args,
        CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "");

    cast<CallInst>(gc_result)->setAttributes(return_attributes);
    return gc_result;
  } else {
    // No return value for the call.
    return nullptr;
  }
}
Esempio n. 8
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/// Replaces the given call site (Call or Invoke) with a gc.statepoint
/// intrinsic with an empty deoptimization arguments list.  This does
/// NOT do explicit relocation for GC support.
static Value *ReplaceWithStatepoint(const CallSite &CS, /* to replace */
                                    Pass *P) {
  assert(CS.getInstruction()->getParent()->getParent()->getParent() &&
         "must be set");

  // TODO: technically, a pass is not allowed to get functions from within a
  // function pass since it might trigger a new function addition.  Refactor
  // this logic out to the initialization of the pass.  Doesn't appear to
  // matter in practice.

  // Then go ahead and use the builder do actually do the inserts.  We insert
  // immediately before the previous instruction under the assumption that all
  // arguments will be available here.  We can't insert afterwards since we may
  // be replacing a terminator.
  IRBuilder<> Builder(CS.getInstruction());

  // Note: The gc args are not filled in at this time, that's handled by
  // RewriteStatepointsForGC (which is currently under review).

  // Create the statepoint given all the arguments
  Instruction *Token = nullptr;
  AttributeSet OriginalAttrs;

  if (CS.isCall()) {
    CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
    CallInst *Call = Builder.CreateGCStatepointCall(
        CS.getCalledValue(), makeArrayRef(CS.arg_begin(), CS.arg_end()), None,
        None, "safepoint_token");
    Call->setTailCall(ToReplace->isTailCall());
    Call->setCallingConv(ToReplace->getCallingConv());

    // Before we have to worry about GC semantics, all attributes are legal
    // TODO: handle param attributes
    OriginalAttrs = ToReplace->getAttributes();

    // In case if we can handle this set of attributes - set up function
    // attributes directly on statepoint and return attributes later for
    // gc_result intrinsic.
    Call->setAttributes(OriginalAttrs.getFnAttributes());

    Token = Call;

    // Put the following gc_result and gc_relocate calls immediately after the
    // the old call (which we're about to delete).
    assert(ToReplace->getNextNode() && "not a terminator, must have next");
    Builder.SetInsertPoint(ToReplace->getNextNode());
    Builder.SetCurrentDebugLocation(ToReplace->getNextNode()->getDebugLoc());
  } else if (CS.isInvoke()) {
    InvokeInst *ToReplace = cast<InvokeInst>(CS.getInstruction());

    // Insert the new invoke into the old block.  We'll remove the old one in a
    // moment at which point this will become the new terminator for the
    // original block.
    Builder.SetInsertPoint(ToReplace->getParent());
    InvokeInst *Invoke = Builder.CreateGCStatepointInvoke(
        CS.getCalledValue(), ToReplace->getNormalDest(),
        ToReplace->getUnwindDest(), makeArrayRef(CS.arg_begin(), CS.arg_end()),
        Builder.getInt32(0), None, "safepoint_token");

    // Currently we will fail on parameter attributes and on certain
    // function attributes.
    OriginalAttrs = ToReplace->getAttributes();

    // In case if we can handle this set of attributes - set up function
    // attributes directly on statepoint and return attributes later for
    // gc_result intrinsic.
    Invoke->setAttributes(OriginalAttrs.getFnAttributes());

    Token = Invoke;

    // We'll insert the gc.result into the normal block
    BasicBlock *NormalDest = normalizeBBForInvokeSafepoint(
        ToReplace->getNormalDest(), Invoke->getParent());
    Builder.SetInsertPoint(NormalDest->getFirstInsertionPt());
  } else {
    llvm_unreachable("unexpect type of CallSite");
  }
  assert(Token);

  // Handle the return value of the original call - update all uses to use a
  // gc_result hanging off the statepoint node we just inserted

  // Only add the gc_result iff there is actually a used result
  if (!CS.getType()->isVoidTy() && !CS.getInstruction()->use_empty()) {
    std::string TakenName =
        CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "";
    CallInst *GCResult = Builder.CreateGCResult(Token, CS.getType(), TakenName);
    GCResult->setAttributes(OriginalAttrs.getRetAttributes());
    return GCResult;
  } else {
    // No return value for the call.
    return nullptr;
  }
}
int compile(list<string> args, list<string> kgen_args,
            string merge, list<string> merge_args,
            string input, string output, int arch,
            string host_compiler, string fileprefix)
{
    //
    // The LLVM compiler to emit IR.
    //
    const char* llvm_compiler = "kernelgen-gfortran";

    //
    // Interpret kernelgen compile options.
    //
    for (list<string>::iterator iarg = kgen_args.begin(),
            iearg = kgen_args.end(); iarg != iearg; iarg++)
    {
        const char* arg = (*iarg).c_str();
        if (!strncmp(arg, "-Wk,--llvm-compiler=", 20))
            llvm_compiler = arg + 20;
    }

    //
    // Generate temporary output file.
    // Check if output file is specified in the command line.
    // Replace or add output to the temporary file.
    //
    cfiledesc tmp_output = cfiledesc::mktemp(fileprefix);
    bool output_specified = false;
    for (list<string>::iterator iarg = args.begin(),
            iearg = args.end(); iarg != iearg; iarg++)
    {
        const char* arg = (*iarg).c_str();
        if (!strcmp(arg, "-o"))
        {
            iarg++;
            *iarg = tmp_output.getFilename();
            output_specified = true;
            break;
        }
    }
    if (!output_specified)
    {
        args.push_back("-o");
        args.push_back(tmp_output.getFilename());
    }

    //
    // 1) Compile source code using regular host compiler.
    //
    {
        if (verbose)
        {
            cout << host_compiler;
            for (list<string>::iterator iarg = args.begin(),
                    iearg = args.end(); iarg != iearg; iarg++)
                cout << " " << *iarg;
            cout << endl;
        }
        int status = execute(host_compiler, args, "", NULL, NULL);
        if (status) return status;
    }

    //
    // 2) Emit LLVM IR.
    //
    string out = "";
    {
        list<string> emit_ir_args;
        for (list<string>::iterator iarg = args.begin(),
                iearg = args.end(); iarg != iearg; iarg++)
        {
            const char* arg = (*iarg).c_str();
            if (!strcmp(arg, "-c") || !strcmp(arg, "-o"))
            {
                iarg++;
                continue;
            }
            if (!strcmp(arg, "-g"))
            {
                continue;
            }
            emit_ir_args.push_back(*iarg);
        }
        emit_ir_args.push_back("-fplugin=/opt/kernelgen/lib/dragonegg.so");
        emit_ir_args.push_back("-fplugin-arg-dragonegg-emit-ir");
        emit_ir_args.push_back("-S");
        emit_ir_args.push_back(input);
        emit_ir_args.push_back("-o");
        emit_ir_args.push_back("-");
        if (verbose)
        {
            cout << llvm_compiler;
            for (list<string>::iterator iarg = emit_ir_args.begin(),
                    iearg = emit_ir_args.end(); iarg != iearg; iarg++)
                cout << " " << *iarg;
            cout << endl;
        }
        int status = execute(llvm_compiler, emit_ir_args, "", &out, NULL);
        if (status) return status;
    }

    //
    // 3) Record existing module functions.
    //
    LLVMContext &context = getGlobalContext();
    SMDiagnostic diag;
    MemoryBuffer* buffer1 = MemoryBuffer::getMemBuffer(out);
    auto_ptr<Module> m1;
    m1.reset(ParseIR(buffer1, diag, context));

    //m1.get()->dump();

    //
    // 4) Inline calls and extract loops into new functions.
    //
    MemoryBuffer* buffer2 = MemoryBuffer::getMemBuffer(out);
    auto_ptr<Module> m2;
    m2.reset(ParseIR(buffer2, diag, context));
    {
        PassManager manager;
        manager.add(createInstructionCombiningPass());
        manager.run(*m2.get());
    }
    std::vector<CallInst *> LoopFuctionCalls;
    {
        PassManager manager;
        manager.add(createBranchedLoopExtractorPass(LoopFuctionCalls));
        manager.run(*m2.get());
    }

    //m2.get()->dump();

    //
    // 5) Replace call to loop functions with call to launcher.
    // Append "always inline" attribute to all other functions.
    //
    Type* int32Ty = Type::getInt32Ty(context);
    Function* launch = Function::Create(
                           TypeBuilder<types::i<32>(types::i<8>*, types::i<64>, types::i<32>*), true>::get(context),
                           GlobalValue::ExternalLinkage, "kernelgen_launch", m2.get());
    for (Module::iterator f1 = m2.get()->begin(), fe1 = m2.get()->end(); f1 != fe1; f1++)
    {
        Function* func = f1;
        if (func->isDeclaration()) continue;

        // Search for the current function in original module
        // functions list.
        // If function is not in list of original module, then
        // it is generated by the loop extractor.
        // Append "always inline" attribute to all other functions.
        if (m1.get()->getFunction(func->getName()))
        {
            const AttrListPtr attr = func->getAttributes();
            const AttrListPtr attr_new = attr.addAttr(~0U, Attribute::AlwaysInline);
            func->setAttributes(attr_new);
            continue;
        }

        // Each such function must be extracted to the
        // standalone module and packed into resulting
        // object file data section.
        if (verbose)
            cout << "Preparing loop function " << func->getName().data() <<
                 " ..." << endl;

        // Reset to default visibility.
        func->setVisibility(GlobalValue::DefaultVisibility);

        // Reset to default linkage.
        func->setLinkage(GlobalValue::ExternalLinkage);

        // Replace call to this function in module with call to launcher.
        bool found = false;
        for (Module::iterator f2 = m2->begin(), fe2 = m2->end(); (f2 != fe2) && !found; f2++)
            for (Function::iterator bb = f2->begin(); (bb != f2->end()) && !found; bb++)
                for (BasicBlock::iterator i = bb->begin(); i != bb->end(); i++)
                {
                    // Check if instruction in focus is a call.
                    CallInst* call = dyn_cast<CallInst>(cast<Value>(i));
                    if (!call) continue;

                    // Check if function is called (needs -instcombine pass).
                    Function* callee = call->getCalledFunction();
                    if (!callee) continue;
                    if (callee->isDeclaration()) continue;
                    if (callee->getName() != func->getName()) continue;

                    // Create a constant array holding original called
                    // function name.
                    Constant* name = ConstantArray::get(
                                         context, callee->getName(), true);

                    // Create and initialize the memory buffer for name.
                    ArrayType* nameTy = cast<ArrayType>(name->getType());
                    AllocaInst* nameAlloc = new AllocaInst(nameTy, "", call);
                    StoreInst* nameInit = new StoreInst(name, nameAlloc, "", call);
                    Value* Idx[2];
                    Idx[0] = Constant::getNullValue(Type::getInt32Ty(context));
                    Idx[1] = ConstantInt::get(Type::getInt32Ty(context), 0);
                    GetElementPtrInst* namePtr = GetElementPtrInst::Create(nameAlloc, Idx, "", call);

                    // Add pointer to the original function string name.
                    SmallVector<Value*, 16> call_args;
                    call_args.push_back(namePtr);

                    // Add size of the aggregated arguments structure.
                    {
                        BitCastInst* BC = new BitCastInst(
                            call->getArgOperand(0), Type::getInt64PtrTy(context),
                            "", call);

                        LoadInst* LI = new LoadInst(BC, "", call);
                        call_args.push_back(LI);
                    }

                    // Add original aggregated structure argument.
                    call_args.push_back(call->getArgOperand(0));

                    // Create new function call with new call arguments
                    // and copy old call properties.
                    CallInst* newcall = CallInst::Create(launch, call_args, "", call);
                    //newcall->takeName(call);
                    newcall->setCallingConv(call->getCallingConv());
                    newcall->setAttributes(call->getAttributes());
                    newcall->setDebugLoc(call->getDebugLoc());

                    // Replace old call with new one.
                    call->replaceAllUsesWith(newcall);
                    call->eraseFromParent();

                    found = true;
                    break;
                }
    }

    //m2.get()->dump();

    //
    // 6) Apply optimization passes to the resulting common
    // module.
    //
    {
        PassManager manager;
        manager.add(createLowerSetJmpPass());
        PassManagerBuilder builder;
        builder.Inliner = createFunctionInliningPass();
        builder.OptLevel = 3;
        builder.DisableSimplifyLibCalls = true;
        builder.populateModulePassManager(manager);
        manager.run(*m2.get());
    }

    //m2.get()->dump();

    //
    // 7) Embed the resulting module into object file.
    //
    {
        string ir_string;
        raw_string_ostream ir(ir_string);
        ir << (*m2.get());
        celf e(tmp_output.getFilename(), output);
        e.getSection(".data")->addSymbol(
            "__kernelgen_" + string(input),
            ir_string.c_str(), ir_string.size() + 1);
    }

    return 0;
}
Esempio n. 10
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//
// Method: runOnModule()
//
// Description:
//  Entry point for this LLVM pass.
//  Clone functions that take LoadInsts as arguments
//
// Inputs:
//  M - A reference to the LLVM module to transform
//
// Outputs:
//  M - The transformed LLVM module.
//
// Return value:
//  true  - The module was modified.
//  false - The module was not modified.
//
bool LoadArgs::runOnModule(Module& M) {
  std::map<std::pair<Function*, const Type * > , Function* > fnCache;
  bool changed;
  do { 
    changed = false;
    for (Module::iterator Func = M.begin(); Func != M.end(); ++Func) {
      for (Function::iterator B = Func->begin(), FE = Func->end(); B != FE; ++B) {
        for (BasicBlock::iterator I = B->begin(), BE = B->end(); I != BE;) {
          CallInst *CI = dyn_cast<CallInst>(I++);
          if(!CI)
            continue;

          if(CI->hasByValArgument())
            continue;
          // if the CallInst calls a function, that is externally defined,
          // or might be changed, ignore this call site.
          Function *F = CI->getCalledFunction();
          if (!F || (F->isDeclaration() || F->mayBeOverridden())) 
            continue;
          if(F->hasStructRetAttr())
            continue;
          if(F->isVarArg())
            continue;

          // find the argument we must replace
          Function::arg_iterator ai = F->arg_begin(), ae = F->arg_end();
          unsigned argNum = 0;
          for(; argNum < CI->getNumArgOperands();argNum++, ++ai) {
            // do not care about dead arguments
            if(ai->use_empty())
              continue;
            if(F->getAttributes().getParamAttributes(argNum).hasAttrSomewhere(Attribute::SExt) ||
               F->getAttributes().getParamAttributes(argNum).hasAttrSomewhere(Attribute::ZExt))
              continue;
            if (isa<LoadInst>(CI->getArgOperand(argNum)))
              break;
          }

          // if no argument was a GEP operator to be changed 
          if(ai == ae)
            continue;

          LoadInst *LI = dyn_cast<LoadInst>(CI->getArgOperand(argNum));
          Instruction * InsertPt = &(Func->getEntryBlock().front());
          AllocaInst *NewVal = new AllocaInst(LI->getType(), "",InsertPt);

          StoreInst *Copy = new StoreInst(LI, NewVal);
          Copy->insertAfter(LI);
          /*if(LI->getParent() != CI->getParent())
            continue;
          // Also check that there is no store after the load.
          // TODO: Check if the load/store do not alias.
          BasicBlock::iterator bii = LI->getParent()->begin();
          Instruction *BII = bii;
          while(BII != LI) {
            ++bii;
            BII = bii;
          }
          while(BII != CI) {
            if(isa<StoreInst>(BII))
              break;
            ++bii;
            BII = bii;
          }
          if(isa<StoreInst>(bii)){
            continue;
          }*/

          // Construct the new Type
          // Appends the struct Type at the beginning
          std::vector<Type*>TP;
          for(unsigned c = 0; c < CI->getNumArgOperands();c++) {
            if(c == argNum)
              TP.push_back(LI->getPointerOperand()->getType());
            TP.push_back(CI->getArgOperand(c)->getType());
          }

          //return type is same as that of original instruction
          FunctionType *NewFTy = FunctionType::get(CI->getType(), TP, false);
          numSimplified++;
          //if(numSimplified > 1000)
          //return true;

          Function *NewF;
          std::map<std::pair<Function*, const Type* > , Function* >::iterator Test;
          Test = fnCache.find(std::make_pair(F, NewFTy));
          if(Test != fnCache.end()) {
            NewF = Test->second;
          } else {
            NewF = Function::Create(NewFTy,
                                    GlobalValue::InternalLinkage,
                                    F->getName().str() + ".TEST",
                                    &M);

            fnCache[std::make_pair(F, NewFTy)] = NewF;
            Function::arg_iterator NI = NewF->arg_begin();

            ValueToValueMapTy ValueMap;

            unsigned count = 0;
            for (Function::arg_iterator II = F->arg_begin(); NI != NewF->arg_end(); ++count, ++NI) {
              if(count == argNum) {
                NI->setName("LDarg");
                continue;
              }
              ValueMap[II] = NI;
              NI->setName(II->getName());
              NI->addAttr(F->getAttributes().getParamAttributes(II->getArgNo() + 1));
              ++II;
            }
            // Perform the cloning.
            SmallVector<ReturnInst*,100> Returns;
            CloneFunctionInto(NewF, F, ValueMap, false, Returns);
            std::vector<Value*> fargs;
            for(Function::arg_iterator ai = NewF->arg_begin(), 
                ae= NewF->arg_end(); ai != ae; ++ai) {
              fargs.push_back(ai);
            }

            NewF->setAttributes(NewF->getAttributes().addAttributes(
                F->getContext(), 0, F->getAttributes().getRetAttributes()));
            NewF->setAttributes(NewF->getAttributes().addAttributes(
                F->getContext(), ~0, F->getAttributes().getFnAttributes()));
            //Get the point to insert the GEP instr.
            Instruction *InsertPoint;
            for (BasicBlock::iterator insrt = NewF->front().begin(); isa<AllocaInst>(InsertPoint = insrt); ++insrt) {;}
            LoadInst *LI_new = new LoadInst(fargs.at(argNum), "", InsertPoint);
            fargs.at(argNum+1)->replaceAllUsesWith(LI_new);
          }
          
          //this does not seem to be a good idea
          AttributeSet NewCallPAL=AttributeSet();
	  
          // Get the initial attributes of the call
          AttributeSet CallPAL = CI->getAttributes();
          AttributeSet RAttrs = CallPAL.getRetAttributes();
          AttributeSet FnAttrs = CallPAL.getFnAttributes();
          if (!RAttrs.isEmpty())
            NewCallPAL=NewCallPAL.addAttributes(F->getContext(),0, RAttrs);

          SmallVector<Value*, 8> Args;
          for(unsigned j =0;j<CI->getNumArgOperands();j++) {
            if(j == argNum) {
              Args.push_back(NewVal);
            }
            Args.push_back(CI->getArgOperand(j));
            // position in the NewCallPAL
            AttributeSet Attrs = CallPAL.getParamAttributes(j+1);
            if (!Attrs.isEmpty())
              NewCallPAL=NewCallPAL.addAttributes(F->getContext(),Args.size(), Attrs);
          }
          // Create the new attributes vec.
          if (!FnAttrs.isEmpty())
            NewCallPAL=NewCallPAL.addAttributes(F->getContext(),~0, FnAttrs);

          CallInst *CallI = CallInst::Create(NewF,Args,"", CI);
          CallI->setCallingConv(CI->getCallingConv());
          CallI->setAttributes(NewCallPAL);
          CI->replaceAllUsesWith(CallI);
          CI->eraseFromParent();
          changed = true;
        }
      }
    }
  } while(changed);
  return true;
}
Esempio n. 11
0
//
// Method: runOnModule()
//
// Description:
//  Entry point for this LLVM pass.
//  Search for all call sites to casted functions.
//  Check if they only differ in an argument type
//  Cast the argument, and call the original function
//
// Inputs:
//  M - A reference to the LLVM module to transform
//
// Outputs:
//  M - The transformed LLVM module.
//
// Return value:
//  true  - The module was modified.
//  false - The module was not modified.
//
bool ArgCast::runOnModule(Module& M) {

  std::vector<CallInst*> worklist;
  for (Module::iterator I = M.begin(); I != M.end(); ++I) {
    if (I->mayBeOverridden())
      continue;
    // Find all uses of this function
    for(Value::user_iterator ui = I->user_begin(), ue = I->user_end(); ui != ue; ) {
      // check if is ever casted to a different function type
      ConstantExpr *CE = dyn_cast<ConstantExpr>(*ui++);
      if(!CE)
        continue;
      if (CE->getOpcode() != Instruction::BitCast)
        continue;
      if(CE->getOperand(0) != I)
        continue;
      const PointerType *PTy = dyn_cast<PointerType>(CE->getType());
      if (!PTy)
        continue;
      const Type *ETy = PTy->getElementType();
      const FunctionType *FTy  = dyn_cast<FunctionType>(ETy); 
      if(!FTy)
        continue;
      // casting to a varargs funtion
      // or function with same number of arguments
      // possibly varying types of arguments
      
      if(FTy->getNumParams() != I->arg_size() && !FTy->isVarArg())
        continue;
      for(Value::user_iterator uii = CE->user_begin(),
          uee = CE->user_end(); uii != uee; ++uii) {
        // Find all uses of the casted value, and check if it is 
        // used in a Call Instruction
        if (CallInst* CI = dyn_cast<CallInst>(*uii)) {
          // Check that it is the called value, and not an argument
          if(CI->getCalledValue() != CE) 
            continue;
          // Check that the number of arguments passed, and expected
          // by the function are the same.
          if(!I->isVarArg()) {
            if(CI->getNumOperands() != I->arg_size() + 1)
              continue;
          } else {
            if(CI->getNumOperands() < I->arg_size() + 1)
              continue;
          }
          // If so, add to worklist
          worklist.push_back(CI);
        }
      }
    }
  }

  // Proces the worklist of potential call sites to transform
  while(!worklist.empty()) {
    CallInst *CI = worklist.back();
    worklist.pop_back();
    // Get the called Function
    Function *F = cast<Function>(CI->getCalledValue()->stripPointerCasts());
    const FunctionType *FTy = F->getFunctionType();

    SmallVector<Value*, 8> Args;
    unsigned i =0;
    for(i =0; i< FTy->getNumParams(); ++i) {
      Type *ArgType = CI->getOperand(i+1)->getType();
      Type *FormalType = FTy->getParamType(i);
      // If the types for this argument match, just add it to the
      // parameter list. No cast needs to be inserted.
      if(ArgType == FormalType) {
        Args.push_back(CI->getOperand(i+1));
      }
      else if(ArgType->isPointerTy() && FormalType->isPointerTy()) {
        CastInst *CastI = CastInst::CreatePointerCast(CI->getOperand(i+1), 
                                                      FormalType, "", CI);
        Args.push_back(CastI);
      } else if (ArgType->isIntegerTy() && FormalType->isIntegerTy()) {
        unsigned SrcBits = ArgType->getScalarSizeInBits();
        unsigned DstBits = FormalType->getScalarSizeInBits();
        if(SrcBits > DstBits) {
          CastInst *CastI = CastInst::CreateIntegerCast(CI->getOperand(i+1), 
                                                        FormalType, true, "", CI);
          Args.push_back(CastI);
        } else {
          if (F->getAttributes().hasAttribute(i+1, Attribute::SExt)) {
            CastInst *CastI = CastInst::CreateIntegerCast(CI->getOperand(i+1), 
                                                          FormalType, true, "", CI);
            Args.push_back(CastI);
          } else if (F->getAttributes().hasAttribute(i+1, Attribute::ZExt)) {
            CastInst *CastI = CastInst::CreateIntegerCast(CI->getOperand(i+1), 
                                                          FormalType, false, "", CI);
            Args.push_back(CastI);
          } else {
            // Use ZExt in default case.
            // Derived from InstCombine. Also, the only reason this should happen
            // is mismatched prototypes.
            // Seen in case of integer constants which get interpreted as i32, 
            // even if being used as i64.
            // TODO: is this correct?
            CastInst *CastI = CastInst::CreateIntegerCast(CI->getOperand(i+1), 
                                                          FormalType, false, "", CI);
            Args.push_back(CastI);
          } 
        } 
      } else {
        DEBUG(ArgType->dump());
        DEBUG(FormalType->dump());
        break;
      }
    }

    // If we found an argument we could not cast, try the next instruction
    if(i != FTy->getNumParams()) {
      continue;
    }

    if(FTy->isVarArg()) {
      for(; i< CI->getNumOperands() - 1 ;i++) {
        Args.push_back(CI->getOperand(i+1));
      }
    }

    // else replace the call instruction
    CallInst *CINew = CallInst::Create(F, Args, "", CI);
    CINew->setCallingConv(CI->getCallingConv());
    CINew->setAttributes(CI->getAttributes());
    if(!CI->use_empty()) {
      CastInst *RetCast;
      if(CI->getType() != CINew->getType()) {
        if(CI->getType()->isPointerTy() && CINew->getType()->isPointerTy())
          RetCast = CastInst::CreatePointerCast(CINew, CI->getType(), "", CI);
        else if(CI->getType()->isIntOrIntVectorTy() && CINew->getType()->isIntOrIntVectorTy())
          RetCast = CastInst::CreateIntegerCast(CINew, CI->getType(), false, "", CI);
        else if(CI->getType()->isIntOrIntVectorTy() && CINew->getType()->isPointerTy())
          RetCast = CastInst::CreatePointerCast(CINew, CI->getType(), "", CI);
        else if(CI->getType()->isPointerTy() && CINew->getType()->isIntOrIntVectorTy()) 
          RetCast = new IntToPtrInst(CINew, CI->getType(), "", CI);
        else {
          // TODO: I'm not sure what right behavior is here, but this case should be handled.
          llvm_unreachable("Unexpected type conversion in call!");
          abort();
        }
        CI->replaceAllUsesWith(RetCast);
      } else {
        CI->replaceAllUsesWith(CINew);
      }
    }

    // Debug printing
    DEBUG(errs() << "ARGCAST:");
    DEBUG(errs() << "ERASE:");
    DEBUG(CI->dump());
    DEBUG(errs() << "ARGCAST:");
    DEBUG(errs() << "ADDED:");
    DEBUG(CINew->dump());

    CI->eraseFromParent();
    numChanged++;
  }
  return true;
}
Esempio n. 12
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/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into
/// an invoke, we have to turn all of the calls that can throw into
/// invokes.  This function analyze BB to see if there are any calls, and if so,
/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI
/// nodes in that block with the values specified in InvokeDestPHIValues.
///
/// Returns true to indicate that the next block should be skipped.
static bool HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
                                                   InvokeInliningInfo &Invoke) {
  for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
    Instruction *I = BBI++;
    
    // We only need to check for function calls: inlined invoke
    // instructions require no special handling.
    CallInst *CI = dyn_cast<CallInst>(I);
    if (CI == 0) continue;

    // LIBUNWIND: merge selector instructions.
    if (EHSelectorInst *Inner = dyn_cast<EHSelectorInst>(CI)) {
      EHSelectorInst *Outer = Invoke.getOuterSelector();
      if (!Outer) continue;

      bool innerIsOnlyCleanup = isCleanupOnlySelector(Inner);
      bool outerIsOnlyCleanup = isCleanupOnlySelector(Outer);

      // If both selectors contain only cleanups, we don't need to do
      // anything.  TODO: this is really just a very specific instance
      // of a much more general optimization.
      if (innerIsOnlyCleanup && outerIsOnlyCleanup) continue;

      // Otherwise, we just append the outer selector to the inner selector.
      SmallVector<Value*, 16> NewSelector;
      for (unsigned i = 0, e = Inner->getNumArgOperands(); i != e; ++i)
        NewSelector.push_back(Inner->getArgOperand(i));
      for (unsigned i = 2, e = Outer->getNumArgOperands(); i != e; ++i)
        NewSelector.push_back(Outer->getArgOperand(i));

      CallInst *NewInner =
        IRBuilder<>(Inner).CreateCall(Inner->getCalledValue(), NewSelector);
      // No need to copy attributes, calling convention, etc.
      NewInner->takeName(Inner);
      Inner->replaceAllUsesWith(NewInner);
      Inner->eraseFromParent();
      continue;
    }
    
    // If this call cannot unwind, don't convert it to an invoke.
    if (CI->doesNotThrow())
      continue;
    
    // Convert this function call into an invoke instruction.
    // First, split the basic block.
    BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");

    // Delete the unconditional branch inserted by splitBasicBlock
    BB->getInstList().pop_back();

    // LIBUNWIND: If this is a call to @llvm.eh.resume, just branch
    // directly to the new landing pad.
    if (Invoke.forwardEHResume(CI, BB)) {
      // TODO: 'Split' is now unreachable; clean it up.

      // We want to leave the original call intact so that the call
      // graph and other structures won't get misled.  We also have to
      // avoid processing the next block, or we'll iterate here forever.
      return true;
    }

    // Otherwise, create the new invoke instruction.
    ImmutableCallSite CS(CI);
    SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end());
    InvokeInst *II =
      InvokeInst::Create(CI->getCalledValue(), Split,
                         Invoke.getOuterUnwindDest(),
                         InvokeArgs, CI->getName(), BB);
    II->setCallingConv(CI->getCallingConv());
    II->setAttributes(CI->getAttributes());
    
    // Make sure that anything using the call now uses the invoke!  This also
    // updates the CallGraph if present, because it uses a WeakVH.
    CI->replaceAllUsesWith(II);

    Split->getInstList().pop_front();  // Delete the original call

    // Update any PHI nodes in the exceptional block to indicate that
    // there is now a new entry in them.
    Invoke.addIncomingPHIValuesFor(BB);
    return false;
  }

  return false;
}
Esempio n. 13
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//
// Method: runOnModule()
//
// Description:
//  Entry point for this LLVM pass.
//  If a function returns a struct, make it return
//  a pointer to the struct.
//
// Inputs:
//  M - A reference to the LLVM module to transform
//
// Outputs:
//  M - The transformed LLVM module.
//
// Return value:
//  true  - The module was modified.
//  false - The module was not modified.
//
bool StructRet::runOnModule(Module& M) {
  const llvm::DataLayout targetData(&M);

  std::vector<Function*> worklist;
  for (Module::iterator I = M.begin(); I != M.end(); ++I)
    if (!I->mayBeOverridden()) {
      if(I->hasAddressTaken())
        continue;
      if(I->getReturnType()->isStructTy()) {
        worklist.push_back(I);
      }
    }

  while(!worklist.empty()) {
    Function *F = worklist.back();
    worklist.pop_back();
    Type *NewArgType = F->getReturnType()->getPointerTo();

    // Construct the new Type
    std::vector<Type*>TP;
    TP.push_back(NewArgType);
    for (Function::arg_iterator ii = F->arg_begin(), ee = F->arg_end();
         ii != ee; ++ii) {
      TP.push_back(ii->getType());
    }

    FunctionType *NFTy = FunctionType::get(F->getReturnType(), TP, F->isVarArg());

    // Create the new function body and insert it into the module.
    Function *NF = Function::Create(NFTy, 
                                    F->getLinkage(),
                                    F->getName(), &M);
    ValueToValueMapTy ValueMap;
    Function::arg_iterator NI = NF->arg_begin();
    NI->setName("ret");
    ++NI;
    for (Function::arg_iterator II = F->arg_begin(); II != F->arg_end(); ++II, ++NI) {
      ValueMap[II] = NI;
      NI->setName(II->getName());
      AttributeSet attrs = F->getAttributes().getParamAttributes(II->getArgNo() + 1);
      if (!attrs.isEmpty())
        NI->addAttr(attrs);
    }
    // Perform the cloning.
    SmallVector<ReturnInst*,100> Returns;
    if (!F->isDeclaration())
      CloneFunctionInto(NF, F, ValueMap, false, Returns);
    std::vector<Value*> fargs;
    for(Function::arg_iterator ai = NF->arg_begin(), 
        ae= NF->arg_end(); ai != ae; ++ai) {
      fargs.push_back(ai);
    }
    NF->setAttributes(NF->getAttributes().addAttributes(
        M.getContext(), 0, F->getAttributes().getRetAttributes()));
    NF->setAttributes(NF->getAttributes().addAttributes(
        M.getContext(), ~0, F->getAttributes().getFnAttributes()));
    
    for (Function::iterator B = NF->begin(), FE = NF->end(); B != FE; ++B) {      
      for (BasicBlock::iterator I = B->begin(), BE = B->end(); I != BE;) {
        ReturnInst * RI = dyn_cast<ReturnInst>(I++);
        if(!RI)
          continue;
        LoadInst *LI = dyn_cast<LoadInst>(RI->getOperand(0));
        assert(LI && "Return should be preceded by a load instruction");
        IRBuilder<> Builder(RI);
        Builder.CreateMemCpy(fargs.at(0),
            LI->getPointerOperand(),
            targetData.getTypeStoreSize(LI->getType()),
            targetData.getPrefTypeAlignment(LI->getType()));
      }
    }

    for(Value::use_iterator ui = F->use_begin(), ue = F->use_end();
        ui != ue; ) {
      CallInst *CI = dyn_cast<CallInst>(*ui++);
      if(!CI)
        continue;
      if(CI->getCalledFunction() != F)
        continue;
      if(CI->hasByValArgument())
        continue;
      AllocaInst *AllocaNew = new AllocaInst(F->getReturnType(), 0, "", CI);
      SmallVector<Value*, 8> Args;

      //this should probably be done in a different manner
      AttributeSet NewCallPAL=AttributeSet();
      
      // Get the initial attributes of the call
      AttributeSet CallPAL = CI->getAttributes();
      AttributeSet RAttrs = CallPAL.getRetAttributes();
      AttributeSet FnAttrs = CallPAL.getFnAttributes();
      
      if (!RAttrs.isEmpty())
        NewCallPAL=NewCallPAL.addAttributes(F->getContext(),0, RAttrs);

      Args.push_back(AllocaNew);
      for(unsigned j = 0; j < CI->getNumOperands()-1; j++) {
        Args.push_back(CI->getOperand(j));
        // position in the NewCallPAL
        AttributeSet Attrs = CallPAL.getParamAttributes(j);
        if (!Attrs.isEmpty())
          NewCallPAL=NewCallPAL.addAttributes(F->getContext(),Args.size(), Attrs);
      }
      // Create the new attributes vec.
      if (!FnAttrs.isEmpty())
        NewCallPAL=NewCallPAL.addAttributes(F->getContext(),~0, FnAttrs);

      CallInst *CallI = CallInst::Create(NF, Args, "", CI);
      CallI->setCallingConv(CI->getCallingConv());
      CallI->setAttributes(NewCallPAL);
      LoadInst *LI = new LoadInst(AllocaNew, "", CI);
      CI->replaceAllUsesWith(LI);
      CI->eraseFromParent();
    }
    if(F->use_empty())
      F->eraseFromParent();
  }
  return true;
}