bool ARM64PromoteConstant::runOnFunction(Function &F) {
// Look for instructions using constant vector
// Promote that constant to a global variable.
// Create as few load of this variable as possible and update the uses
// accordingly
bool LocalChange = false;
SmallSet<Constant *, 8> AlreadyChecked;
for (Function::iterator IBB = F.begin(), IEndBB = F.end();
IBB != IEndBB; ++IBB) {
for (BasicBlock::iterator II = IBB->begin(), IEndI = IBB->end();
II != IEndI; ++II) {
// Traverse the operand, looking for constant vectors
// Replace them by a load of a global variable of type constant vector
for (unsigned OpIdx = 0, EndOpIdx = II->getNumOperands();
OpIdx != EndOpIdx; ++OpIdx) {
Constant *Cst = dyn_cast<Constant>(II->getOperand(OpIdx));
// There is no point is promoting global value, they are already global.
// Do not promote constant expression, as they may require some code
// expansion.
if (Cst && !isa<GlobalValue>(Cst) && !isa<ConstantExpr>(Cst) &&
AlreadyChecked.insert(Cst))
LocalChange |= promoteConstant(Cst);
}
}
}
return LocalChange;
}
bool llvm::ValueCounter::runOnModule(Module& M) {
std::set<Value*> values;
for(Module::iterator Fit = M.begin(), Fend = M.end(); Fit != Fend; Fit++){
if (!values.count(Fit)) values.insert(Fit);
for(Function::arg_iterator Arg = Fit->arg_begin(), aEnd = Fit->arg_end(); Arg != aEnd; Arg++) {
if (!values.count(Arg)) values.insert(Arg);
}
for (Function::iterator BBit = Fit->begin(), BBend = Fit->end(); BBit != BBend; BBit++) {
for (BasicBlock::iterator Iit = BBit->begin(), Iend = BBit->end(); Iit != Iend; Iit++) {
if (!values.count(Iit)) values.insert(Iit);
for(unsigned int i = 0; i < Iit->getNumOperands(); i++){
if (!values.count(Iit->getOperand(i))) values.insert(Iit->getOperand(i));
}
}
}
}
TotalValues = values.size();
//We don't modify anything, so we must return false;
return false;
}
void LowerEmAsyncify::FindContextVariables(AsyncCallEntry & Entry) {
BasicBlock *AfterCallBlock = Entry.AfterCallBlock;
Function & F = *AfterCallBlock->getParent();
// Create a new entry block as if in the callback function
// theck check variables that no longer properly dominate their uses
BasicBlock *EntryBlock = BasicBlock::Create(TheModule->getContext(), "", &F, &F.getEntryBlock());
BranchInst::Create(AfterCallBlock, EntryBlock);
DominatorTreeWrapperPass DTW;
DTW.runOnFunction(F);
DominatorTree& DT = DTW.getDomTree();
// These blocks may be using some values defined at or before AsyncCallBlock
BasicBlockSet Ramifications = FindReachableBlocksFrom(AfterCallBlock);
SmallPtrSet<Value*, 256> ContextVariables;
Values Pending;
// Examine the instructions, find all variables that we need to store in the context
for (BasicBlockSet::iterator RI = Ramifications.begin(), RE = Ramifications.end(); RI != RE; ++RI) {
for (BasicBlock::iterator I = (*RI)->begin(), E = (*RI)->end(); I != E; ++I) {
for (unsigned i = 0, NumOperands = I->getNumOperands(); i < NumOperands; ++i) {
Value *O = I->getOperand(i);
if (Instruction *Inst = dyn_cast<Instruction>(O)) {
if (Inst == Entry.AsyncCallInst) continue; // for the original async call, we will load directly from async return value
if (ContextVariables.count(Inst) != 0) continue; // already examined
if (!DT.dominates(Inst, I->getOperandUse(i))) {
// `I` is using `Inst`, yet `Inst` does not dominate `I` if we arrive directly at AfterCallBlock
// so we need to save `Inst` in the context
ContextVariables.insert(Inst);
Pending.push_back(Inst);
}
} else if (Argument *Arg = dyn_cast<Argument>(O)) {
// count() should be as fast/slow as insert, so just insert here
ContextVariables.insert(Arg);
}
}
}
}
// restore F
EntryBlock->eraseFromParent();
Entry.ContextVariables.clear();
Entry.ContextVariables.reserve(ContextVariables.size());
for (SmallPtrSet<Value*, 256>::iterator I = ContextVariables.begin(), E = ContextVariables.end(); I != E; ++I) {
Entry.ContextVariables.push_back(*I);
}
}
void LTOModule::addDefinedFunctionSymbol(Function* f, Mangler &mangler)
{
// add to list of defined symbols
addDefinedSymbol(f, mangler, true);
// add external symbols referenced by this function.
for (Function::iterator b = f->begin(); b != f->end(); ++b) {
for (BasicBlock::iterator i = b->begin(); i != b->end(); ++i) {
for (unsigned count = 0, total = i->getNumOperands();
count != total; ++count) {
findExternalRefs(i->getOperand(count), mangler);
}
}
}
}
/// eliminateUnconditionalBranch - Clone the instructions from the destination
/// block into the source block, eliminating the specified unconditional branch.
/// If the destination block defines values used by successors of the dest
/// block, we may need to insert PHI nodes.
///
void TailDup::eliminateUnconditionalBranch(BranchInst *Branch) {
BasicBlock *SourceBlock = Branch->getParent();
BasicBlock *DestBlock = Branch->getSuccessor(0);
assert(SourceBlock != DestBlock && "Our predicate is broken!");
DEBUG(errs() << "TailDuplication[" << SourceBlock->getParent()->getName()
<< "]: Eliminating branch: " << *Branch);
// See if we can avoid duplicating code by moving it up to a dominator of both
// blocks.
if (BasicBlock *DomBlock = FindObviousSharedDomOf(SourceBlock, DestBlock)) {
DEBUG(errs() << "Found shared dominator: " << DomBlock->getName() << "\n");
// If there are non-phi instructions in DestBlock that have no operands
// defined in DestBlock, and if the instruction has no side effects, we can
// move the instruction to DomBlock instead of duplicating it.
BasicBlock::iterator BBI = DestBlock->getFirstNonPHI();
while (!isa<TerminatorInst>(BBI)) {
Instruction *I = BBI++;
bool CanHoist = I->isSafeToSpeculativelyExecute() &&
!I->mayReadFromMemory();
if (CanHoist) {
for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op)
if (Instruction *OpI = dyn_cast<Instruction>(I->getOperand(op)))
if (OpI->getParent() == DestBlock ||
(isa<InvokeInst>(OpI) && OpI->getParent() == DomBlock)) {
CanHoist = false;
break;
}
if (CanHoist) {
// Remove from DestBlock, move right before the term in DomBlock.
DestBlock->getInstList().remove(I);
DomBlock->getInstList().insert(DomBlock->getTerminator(), I);
DEBUG(errs() << "Hoisted: " << *I);
}
}
}
}
// Tail duplication can not update SSA properties correctly if the values
// defined in the duplicated tail are used outside of the tail itself. For
// this reason, we spill all values that are used outside of the tail to the
// stack.
for (BasicBlock::iterator I = DestBlock->begin(); I != DestBlock->end(); ++I)
if (I->isUsedOutsideOfBlock(DestBlock)) {
// We found a use outside of the tail. Create a new stack slot to
// break this inter-block usage pattern.
DemoteRegToStack(*I);
}
// We are going to have to map operands from the original block B to the new
// copy of the block B'. If there are PHI nodes in the DestBlock, these PHI
// nodes also define part of this mapping. Loop over these PHI nodes, adding
// them to our mapping.
//
std::map<Value*, Value*> ValueMapping;
BasicBlock::iterator BI = DestBlock->begin();
bool HadPHINodes = isa<PHINode>(BI);
for (; PHINode *PN = dyn_cast<PHINode>(BI); ++BI)
ValueMapping[PN] = PN->getIncomingValueForBlock(SourceBlock);
// Clone the non-phi instructions of the dest block into the source block,
// keeping track of the mapping...
//
for (; BI != DestBlock->end(); ++BI) {
Instruction *New = BI->clone();
New->setName(BI->getName());
SourceBlock->getInstList().push_back(New);
ValueMapping[BI] = New;
}
// Now that we have built the mapping information and cloned all of the
// instructions (giving us a new terminator, among other things), walk the new
// instructions, rewriting references of old instructions to use new
// instructions.
//
BI = Branch; ++BI; // Get an iterator to the first new instruction
for (; BI != SourceBlock->end(); ++BI)
for (unsigned i = 0, e = BI->getNumOperands(); i != e; ++i) {
std::map<Value*, Value*>::const_iterator I =
ValueMapping.find(BI->getOperand(i));
if (I != ValueMapping.end())
BI->setOperand(i, I->second);
}
// Next we check to see if any of the successors of DestBlock had PHI nodes.
// If so, we need to add entries to the PHI nodes for SourceBlock now.
for (succ_iterator SI = succ_begin(DestBlock), SE = succ_end(DestBlock);
SI != SE; ++SI) {
BasicBlock *Succ = *SI;
for (BasicBlock::iterator PNI = Succ->begin(); isa<PHINode>(PNI); ++PNI) {
PHINode *PN = cast<PHINode>(PNI);
// Ok, we have a PHI node. Figure out what the incoming value was for the
// DestBlock.
Value *IV = PN->getIncomingValueForBlock(DestBlock);
// Remap the value if necessary...
std::map<Value*, Value*>::const_iterator I = ValueMapping.find(IV);
if (I != ValueMapping.end())
IV = I->second;
PN->addIncoming(IV, SourceBlock);
}
}
// Next, remove the old branch instruction, and any PHI node entries that we
// had.
BI = Branch; ++BI; // Get an iterator to the first new instruction
DestBlock->removePredecessor(SourceBlock); // Remove entries in PHI nodes...
SourceBlock->getInstList().erase(Branch); // Destroy the uncond branch...
// Final step: now that we have finished everything up, walk the cloned
// instructions one last time, constant propagating and DCE'ing them, because
// they may not be needed anymore.
//
if (HadPHINodes) {
while (BI != SourceBlock->end()) {
Instruction *Inst = BI++;
if (isInstructionTriviallyDead(Inst))
Inst->eraseFromParent();
else if (Constant *C = ConstantFoldInstruction(Inst)) {
Inst->replaceAllUsesWith(C);
Inst->eraseFromParent();
}
}
}
++NumEliminated; // We just killed a branch!
}
bool GenericToNVVM::runOnModule(Module &M) {
// Create a clone of each global variable that has the default address space.
// The clone is created with the global address space specifier, and the pair
// of original global variable and its clone is placed in the GVMap for later
// use.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E;) {
GlobalVariable *GV = &*I++;
if (GV->getType()->getAddressSpace() == llvm::ADDRESS_SPACE_GENERIC &&
!llvm::isTexture(*GV) && !llvm::isSurface(*GV) &&
!llvm::isSampler(*GV) && !GV->getName().startswith("llvm.")) {
GlobalVariable *NewGV = new GlobalVariable(
M, GV->getValueType(), GV->isConstant(),
GV->getLinkage(),
GV->hasInitializer() ? GV->getInitializer() : nullptr,
"", GV, GV->getThreadLocalMode(), llvm::ADDRESS_SPACE_GLOBAL);
NewGV->copyAttributesFrom(GV);
GVMap[GV] = NewGV;
}
}
// Return immediately, if every global variable has a specific address space
// specifier.
if (GVMap.empty()) {
return false;
}
// Walk through the instructions in function defitinions, and replace any use
// of original global variables in GVMap with a use of the corresponding
// copies in GVMap. If necessary, promote constants to instructions.
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
if (I->isDeclaration()) {
continue;
}
IRBuilder<> Builder(I->getEntryBlock().getFirstNonPHIOrDbg());
for (Function::iterator BBI = I->begin(), BBE = I->end(); BBI != BBE;
++BBI) {
for (BasicBlock::iterator II = BBI->begin(), IE = BBI->end(); II != IE;
++II) {
for (unsigned i = 0, e = II->getNumOperands(); i < e; ++i) {
Value *Operand = II->getOperand(i);
if (isa<Constant>(Operand)) {
II->setOperand(
i, remapConstant(&M, &*I, cast<Constant>(Operand), Builder));
}
}
}
}
ConstantToValueMap.clear();
}
// Copy GVMap over to a standard value map.
ValueToValueMapTy VM;
for (auto I = GVMap.begin(), E = GVMap.end(); I != E; ++I)
VM[I->first] = I->second;
// Walk through the metadata section and update the debug information
// associated with the global variables in the default address space.
for (NamedMDNode &I : M.named_metadata()) {
remapNamedMDNode(VM, &I);
}
// Walk through the global variable initializers, and replace any use of
// original global variables in GVMap with a use of the corresponding copies
// in GVMap. The copies need to be bitcast to the original global variable
// types, as we cannot use cvta in global variable initializers.
for (GVMapTy::iterator I = GVMap.begin(), E = GVMap.end(); I != E;) {
GlobalVariable *GV = I->first;
GlobalVariable *NewGV = I->second;
// Remove GV from the map so that it can be RAUWed. Note that
// DenseMap::erase() won't invalidate any iterators but this one.
auto Next = std::next(I);
GVMap.erase(I);
I = Next;
Constant *BitCastNewGV = ConstantExpr::getPointerCast(NewGV, GV->getType());
// At this point, the remaining uses of GV should be found only in global
// variable initializers, as other uses have been already been removed
// while walking through the instructions in function definitions.
GV->replaceAllUsesWith(BitCastNewGV);
std::string Name = GV->getName();
GV->eraseFromParent();
NewGV->setName(Name);
}
assert(GVMap.empty() && "Expected it to be empty by now");
return true;
}
void SuperBlock::fixSideEntrances() {
// due to merging of BBs, some superblocks may have 1 BB remaining
list<map<BasicBlock*, list<BasicBlock*> >::iterator > delSuperBlocks;
for (map<BasicBlock*, list<BasicBlock*> >::iterator sp = superBlocks.begin(),
sp_e = superBlocks.end(); sp != sp_e; ++sp) {
// we need to keep track of the predecessor of the current basic block
// being checked
BasicBlock* prev = sp->first;
// don't clone basic blocks if the code size threshold is achieved
if (currCodeSize/originalCodeSize > CODE_EXPANSION_THRESHOLD) {
break;
}
// the first basic block for a superblock need not be duplicated
for (list<BasicBlock*>::iterator bb = sp->second.begin(),
bb_e = sp->second.end(); bb != bb_e; ++bb) {
// first, collect all predecessors for this BB
// (note: we could not just iterate through as the predecessor set may
// change
list<BasicBlock*> predBBs;
for (pred_iterator pred = pred_begin(*bb), pred_e = pred_end(*bb);
pred != pred_e; ++pred) {
predBBs.push_back(*pred);
}
// now, walk through all predecessors of this current basic block
BasicBlock* clonedBB = NULL;
for (list<BasicBlock*>::iterator pred = predBBs.begin(),
pred_e = predBBs.end(); pred != pred_e; ++pred) {
// if it is not the predecessor of this current basic block present in
// the superblock, duplicate!
if (*pred != prev) {
// there is no need to clone this BB multiple times
if (clonedBB == NULL) {
ValueToValueMapTy vmap;
// clone this basic block, and place the corresponding code after
// the last BB of this superblock
clonedBB = CloneBasicBlock(*bb, vmap, ".cloned",
(*bb)->getParent());
vmap[*bb] = clonedBB;
/*
errs() << "@@ BEFORE: " << *clonedBB << "\n";
// fix phi nodes in the cloned BB
for (BasicBlock::iterator I = clonedBB->begin(); isa<PHINode>(I); ++I) {
PHINode* PN = dyn_cast<PHINode>(I);
int bbIdx = PN->getBasicBlockIndex(prev);
if (bbIdx != -1) {
PN->removeIncomingValue(bbIdx, false);
}
}
*/
// add size of duplicated BBs to total code size count
currCodeSize += clonedBB->size();
// modify operands in this basic block
for (BasicBlock::iterator instr = clonedBB->begin(),
instr_e = clonedBB->end(); instr != instr_e; ++instr) {
for (unsigned idx = 0, num_ops = instr->getNumOperands();
idx < num_ops; ++idx) {
Value* op = instr->getOperand(idx);
ValueToValueMapTy::iterator op_it = vmap.find(op);
if (op_it != vmap.end()) {
instr->setOperand(idx, op_it->second);
}
}
}
}
// remove phi nodes into this BB in the trace
/*
for (BasicBlock::iterator I = (*bb)->begin(); isa<PHINode>(I); ++I) {
PHINode* PN = dyn_cast<PHINode>(I);
int bbIdx = PN->getBasicBlockIndex(*pred);
if (bbIdx != -1) {
PN->removeIncomingValue(bbIdx, false);
}
}
*/
// modify the branch instruction of the predecessor not in the superblock to
// branch to the cloned basic block
Instruction* br_instr = (*pred)->getTerminator();
br_instr->replaceUsesOfWith((Value*)*bb, (Value*)clonedBB);
}
}
// determine if we can merge the BB (definitely can be merged), and its clone
// with theirpredecessors
if (clonedBB != NULL) {
if (MergeBlockIntoPredecessor(*bb, this)) {
// since we have merged this BB, delete from our superblock mappings
partOfSuperBlock.erase(*bb);
bb = sp->second.erase(bb);
--bb;
if (sp->second.empty()) {
delSuperBlocks.push_back(sp);
}
}
MergeBlockIntoPredecessor(clonedBB, this);
}
prev = *bb;
}
}
// erase some superblocks (which only have 1 BB remaining)
for (list<map<BasicBlock*, list<BasicBlock*> >::iterator >::iterator del =
delSuperBlocks.begin(), del_e = delSuperBlocks.end(); del != del_e;
++del) {
superBlocks.erase(*del);
}
}
/// InputFilename is a LLVM bitcode file. Read it using bitcode reader.
/// Collect global functions and symbol names in symbols vector.
/// Collect external references in references vector.
/// Return LTO_READ_SUCCESS if there is no error.
enum LTOStatus
LTO::readLLVMObjectFile(const std::string &InputFilename,
NameToSymbolMap &symbols,
std::set<std::string> &references)
{
Module *m = getModule(InputFilename);
if (!m)
return LTO_READ_FAILURE;
// Collect Target info
getTarget(m);
if (!Target)
return LTO_READ_FAILURE;
// Use mangler to add GlobalPrefix to names to match linker names.
// FIXME : Instead of hard coding "-" use GlobalPrefix.
Mangler mangler(*m, Target->getTargetAsmInfo()->getGlobalPrefix());
modules.push_back(m);
for (Module::iterator f = m->begin(), e = m->end(); f != e; ++f) {
LTOLinkageTypes lt = getLTOLinkageType(f);
LTOVisibilityTypes vis = getLTOVisibilityType(f);
if (!f->isDeclaration() && lt != LTOInternalLinkage
&& strncmp (f->getName().c_str(), "llvm.", 5)) {
int alignment = ( 16 > f->getAlignment() ? 16 : f->getAlignment());
LLVMSymbol *newSymbol = new LLVMSymbol(lt, vis, f, f->getName(),
mangler.getValueName(f),
Log2_32(alignment));
symbols[newSymbol->getMangledName()] = newSymbol;
allSymbols[newSymbol->getMangledName()] = newSymbol;
}
// Collect external symbols referenced by this function.
for (Function::iterator b = f->begin(), fe = f->end(); b != fe; ++b)
for (BasicBlock::iterator i = b->begin(), be = b->end();
i != be; ++i) {
for (unsigned count = 0, total = i->getNumOperands();
count != total; ++count)
findExternalRefs(i->getOperand(count), references, mangler);
}
}
for (Module::global_iterator v = m->global_begin(), e = m->global_end();
v != e; ++v) {
LTOLinkageTypes lt = getLTOLinkageType(v);
LTOVisibilityTypes vis = getLTOVisibilityType(v);
if (!v->isDeclaration() && lt != LTOInternalLinkage
&& strncmp (v->getName().c_str(), "llvm.", 5)) {
const TargetData *TD = Target->getTargetData();
LLVMSymbol *newSymbol = new LLVMSymbol(lt, vis, v, v->getName(),
mangler.getValueName(v),
TD->getPreferredAlignmentLog(v));
symbols[newSymbol->getMangledName()] = newSymbol;
allSymbols[newSymbol->getMangledName()] = newSymbol;
for (unsigned count = 0, total = v->getNumOperands();
count != total; ++count)
findExternalRefs(v->getOperand(count), references, mangler);
}
}
return LTO_READ_SUCCESS;
}