//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
+#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/Loads.h"
#include "llvm/IR/DataLayout.h"
if (CS.isCallee(&U))
continue;
+ unsigned DataOpNo = CS.getDataOperandNo(&U);
+ bool IsArgOperand = CS.isArgOperand(&U);
+
// Inalloca arguments are clobbered by the call.
- unsigned ArgNo = CS.getArgumentNo(&U);
- if (CS.isInAllocaArgument(ArgNo))
+ if (IsArgOperand && CS.isInAllocaArgument(DataOpNo))
return false;
// If this is a readonly/readnone call site, then we know it is just a
// load (but one that potentially returns the value itself), so we can
// ignore it if we know that the value isn't captured.
if (CS.onlyReadsMemory() &&
- (CS.getInstruction()->use_empty() || CS.doesNotCapture(ArgNo)))
+ (CS.getInstruction()->use_empty() || CS.doesNotCapture(DataOpNo)))
continue;
// If this is being passed as a byval argument, the caller is making a
// copy, so it is only a read of the alloca.
- if (CS.isByValArgument(ArgNo))
+ if (IsArgOperand && CS.isByValArgument(DataOpNo))
continue;
}
if (auto *ST = dyn_cast<StructType>(T)) {
// If the struct only have one element, we unpack.
- if (ST->getNumElements() == 1) {
+ unsigned Count = ST->getNumElements();
+ if (Count == 1) {
LoadInst *NewLoad = combineLoadToNewType(IC, LI, ST->getTypeAtIndex(0U),
".unpack");
return IC.ReplaceInstUsesWith(LI, IC.Builder->CreateInsertValue(
UndefValue::get(T), NewLoad, 0, LI.getName()));
}
+
+ // We don't want to break loads with padding here as we'd loose
+ // the knowledge that padding exists for the rest of the pipeline.
+ const DataLayout &DL = IC.getDataLayout();
+ auto *SL = DL.getStructLayout(ST);
+ if (SL->hasPadding())
+ return nullptr;
+
+ auto Name = LI.getName();
+ SmallString<16> LoadName = Name;
+ LoadName += ".unpack";
+ SmallString<16> EltName = Name;
+ EltName += ".elt";
+ auto *Addr = LI.getPointerOperand();
+ Value *V = UndefValue::get(T);
+ auto *IdxType = Type::getInt32Ty(ST->getContext());
+ auto *Zero = ConstantInt::get(IdxType, 0);
+ for (unsigned i = 0; i < Count; i++) {
+ Value *Indices[2] = {
+ Zero,
+ ConstantInt::get(IdxType, i),
+ };
+ auto *Ptr = IC.Builder->CreateInBoundsGEP(ST, Addr, makeArrayRef(Indices), EltName);
+ auto *L = IC.Builder->CreateLoad(ST->getTypeAtIndex(i), Ptr, LoadName);
+ V = IC.Builder->CreateInsertValue(V, L, i);
+ }
+
+ V->setName(Name);
+ return IC.ReplaceInstUsesWith(LI, V);
}
if (auto *AT = dyn_cast<ArrayType>(T)) {
if (auto *ST = dyn_cast<StructType>(T)) {
// If the struct only have one element, we unpack.
- if (ST->getNumElements() == 1) {
+ unsigned Count = ST->getNumElements();
+ if (Count == 1) {
V = IC.Builder->CreateExtractValue(V, 0);
combineStoreToNewValue(IC, SI, V);
return true;
}
+
+ // We don't want to break loads with padding here as we'd loose
+ // the knowledge that padding exists for the rest of the pipeline.
+ const DataLayout &DL = IC.getDataLayout();
+ auto *SL = DL.getStructLayout(ST);
+ if (SL->hasPadding())
+ return false;
+
+ SmallString<16> EltName = V->getName();
+ EltName += ".elt";
+ auto *Addr = SI.getPointerOperand();
+ SmallString<16> AddrName = Addr->getName();
+ AddrName += ".repack";
+ auto *IdxType = Type::getInt32Ty(ST->getContext());
+ auto *Zero = ConstantInt::get(IdxType, 0);
+ for (unsigned i = 0; i < Count; i++) {
+ Value *Indices[2] = {
+ Zero,
+ ConstantInt::get(IdxType, i),
+ };
+ auto *Ptr = IC.Builder->CreateInBoundsGEP(ST, Addr, makeArrayRef(Indices), AddrName);
+ auto *Val = IC.Builder->CreateExtractValue(V, i, EltName);
+ IC.Builder->CreateStore(Val, Ptr);
+ }
+
+ return true;
}
if (auto *AT = dyn_cast<ArrayType>(T)) {
return &SI;
}
- // Don't hack volatile/atomic stores.
- // FIXME: Some bits are legal for atomic stores; needs refactoring.
- if (!SI.isSimple()) return nullptr;
+ // Don't hack volatile/ordered stores.
+ // FIXME: Some bits are legal for ordered atomic stores; needs refactoring.
+ if (!SI.isUnordered()) return nullptr;
// If the RHS is an alloca with a single use, zapify the store, making the
// alloca dead.
if (StoreInst *PrevSI = dyn_cast<StoreInst>(BBI)) {
// Prev store isn't volatile, and stores to the same location?
- if (PrevSI->isSimple() && equivalentAddressValues(PrevSI->getOperand(1),
+ if (PrevSI->isUnordered() && equivalentAddressValues(PrevSI->getOperand(1),
SI.getOperand(1))) {
++NumDeadStore;
++BBI;
// the pointer we're loading and is producing the pointer we're storing,
// then *this* store is dead (X = load P; store X -> P).
if (LoadInst *LI = dyn_cast<LoadInst>(BBI)) {
- if (LI == Val && equivalentAddressValues(LI->getOperand(0), Ptr) &&
- LI->isSimple())
+ if (LI == Val && equivalentAddressValues(LI->getOperand(0), Ptr)) {
+ assert(SI.isUnordered() && "can't eliminate ordering operation");
return EraseInstFromFunction(SI);
+ }
// Otherwise, this is a load from some other location. Stores before it
// may not be dead.
if (isa<UndefValue>(Val))
return EraseInstFromFunction(SI);
+ // The code below needs to be audited and adjusted for unordered atomics
+ if (!SI.isSimple())
+ return nullptr;
+
// If this store is the last instruction in the basic block (possibly
// excepting debug info instructions), and if the block ends with an
// unconditional branch, try to move it to the successor block.