OpaquePtr: add Type parameter to Loads analysis API.
This makes the functions in Loads.h require a type to be specified
independently of the pointer Value so that when pointers have no structure
other than address-space, it can still do its job.
Most callers had an obvious memory operation handy to provide this type, but a
SROA and ArgumentPromotion were doing more complicated analysis. They get
updated to merge the properties of the various instructions they were
considering.
llvm-svn: 365468
diff --git a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
index 8b77adc..95a9f31 100644
--- a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -479,9 +479,9 @@
return NF;
}
-/// AllCallersPassInValidPointerForArgument - Return true if we can prove that
-/// all callees pass in a valid pointer for the specified function argument.
-static bool allCallersPassInValidPointerForArgument(Argument *Arg) {
+/// Return true if we can prove that all callees pass in a valid pointer for the
+/// specified function argument.
+static bool allCallersPassValidPointerForArgument(Argument *Arg, Type *Ty) {
Function *Callee = Arg->getParent();
const DataLayout &DL = Callee->getParent()->getDataLayout();
@@ -493,7 +493,7 @@
CallSite CS(U);
assert(CS && "Should only have direct calls!");
- if (!isDereferenceablePointer(CS.getArgument(ArgNo), DL))
+ if (!isDereferenceablePointer(CS.getArgument(ArgNo), Ty, DL))
return false;
}
return true;
@@ -566,7 +566,7 @@
/// This method limits promotion of aggregates to only promote up to three
/// elements of the aggregate in order to avoid exploding the number of
/// arguments passed in.
-static bool isSafeToPromoteArgument(Argument *Arg, bool isByVal, AAResults &AAR,
+static bool isSafeToPromoteArgument(Argument *Arg, Type *ByValTy, AAResults &AAR,
unsigned MaxElements) {
using GEPIndicesSet = std::set<IndicesVector>;
@@ -596,9 +596,28 @@
GEPIndicesSet ToPromote;
// If the pointer is always valid, any load with first index 0 is valid.
- if (isByVal || allCallersPassInValidPointerForArgument(Arg))
+
+ if (ByValTy)
SafeToUnconditionallyLoad.insert(IndicesVector(1, 0));
+ // Whenever a new underlying type for the operand is found, make sure it's
+ // consistent with the GEPs and loads we've already seen and, if necessary,
+ // use it to see if all incoming pointers are valid (which implies the 0-index
+ // is safe).
+ Type *BaseTy = ByValTy;
+ auto UpdateBaseTy = [&](Type *NewBaseTy) {
+ if (BaseTy)
+ return BaseTy == NewBaseTy;
+
+ BaseTy = NewBaseTy;
+ if (allCallersPassValidPointerForArgument(Arg, BaseTy)) {
+ assert(SafeToUnconditionallyLoad.empty());
+ SafeToUnconditionallyLoad.insert(IndicesVector(1, 0));
+ }
+
+ return true;
+ };
+
// First, iterate the entry block and mark loads of (geps of) arguments as
// safe.
BasicBlock &EntryBlock = Arg->getParent()->front();
@@ -621,6 +640,9 @@
// right away, can't promote this argument at all.
return false;
+ if (!UpdateBaseTy(GEP->getSourceElementType()))
+ return false;
+
// Indices checked out, mark them as safe
markIndicesSafe(Indices, SafeToUnconditionallyLoad);
Indices.clear();
@@ -628,6 +650,11 @@
} else if (V == Arg) {
// Direct loads are equivalent to a GEP with a single 0 index.
markIndicesSafe(IndicesVector(1, 0), SafeToUnconditionallyLoad);
+
+ if (BaseTy && LI->getType() != BaseTy)
+ return false;
+
+ BaseTy = LI->getType();
}
}
@@ -645,6 +672,9 @@
Loads.push_back(LI);
// Direct loads are equivalent to a GEP with a zero index and then a load.
Operands.push_back(0);
+
+ if (!UpdateBaseTy(LI->getType()))
+ return false;
} else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(UR)) {
if (GEP->use_empty()) {
// Dead GEP's cause trouble later. Just remove them if we run into
@@ -653,9 +683,12 @@
// TODO: This runs the above loop over and over again for dead GEPs
// Couldn't we just do increment the UI iterator earlier and erase the
// use?
- return isSafeToPromoteArgument(Arg, isByVal, AAR, MaxElements);
+ return isSafeToPromoteArgument(Arg, ByValTy, AAR, MaxElements);
}
+ if (!UpdateBaseTy(GEP->getSourceElementType()))
+ return false;
+
// Ensure that all of the indices are constants.
for (User::op_iterator i = GEP->idx_begin(), e = GEP->idx_end(); i != e;
++i)
@@ -966,8 +999,9 @@
}
// Otherwise, see if we can promote the pointer to its value.
- if (isSafeToPromoteArgument(PtrArg, PtrArg->hasByValAttr(), AAR,
- MaxElements))
+ Type *ByValTy =
+ PtrArg->hasByValAttr() ? PtrArg->getParamByValType() : nullptr;
+ if (isSafeToPromoteArgument(PtrArg, ByValTy, AAR, MaxElements))
ArgsToPromote.insert(PtrArg);
}
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 63f313e..4b3333a 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1060,7 +1060,7 @@
// If we can unconditionally load from this address, replace with a
// load/select idiom. TODO: use DT for context sensitive query
- if (isDereferenceableAndAlignedPointer(LoadPtr, Alignment,
+ if (isDereferenceableAndAlignedPointer(LoadPtr, II.getType(), Alignment,
II.getModule()->getDataLayout(),
&II, nullptr)) {
Value *LI = Builder.CreateAlignedLoad(II.getType(), LoadPtr, Alignment,
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 0df80e0..054fb7d 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -1064,8 +1064,10 @@
if (SelectInst *SI = dyn_cast<SelectInst>(Op)) {
// load (select (Cond, &V1, &V2)) --> select(Cond, load &V1, load &V2).
unsigned Align = LI.getAlignment();
- if (isSafeToLoadUnconditionally(SI->getOperand(1), Align, DL, SI) &&
- isSafeToLoadUnconditionally(SI->getOperand(2), Align, DL, SI)) {
+ if (isSafeToLoadUnconditionally(SI->getOperand(1), LI.getType(), Align,
+ DL, SI) &&
+ isSafeToLoadUnconditionally(SI->getOperand(2), LI.getType(), Align,
+ DL, SI)) {
LoadInst *V1 =
Builder.CreateLoad(LI.getType(), SI->getOperand(1),
SI->getOperand(1)->getName() + ".val");
diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp
index 2d27a66..3c5e773 100644
--- a/llvm/lib/Transforms/Scalar/LICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LICM.cpp
@@ -2016,8 +2016,8 @@
// deref info through it.
if (!DereferenceableInPH) {
DereferenceableInPH = isDereferenceableAndAlignedPointer(
- Store->getPointerOperand(), Store->getAlignment(), MDL,
- Preheader->getTerminator(), DT);
+ Store->getPointerOperand(), Store->getValueOperand()->getType(),
+ Store->getAlignment(), MDL, Preheader->getTerminator(), DT);
}
} else
return false; // Not a load or store.
diff --git a/llvm/lib/Transforms/Scalar/MergeICmps.cpp b/llvm/lib/Transforms/Scalar/MergeICmps.cpp
index 630f029..3d047a1 100644
--- a/llvm/lib/Transforms/Scalar/MergeICmps.cpp
+++ b/llvm/lib/Transforms/Scalar/MergeICmps.cpp
@@ -162,7 +162,7 @@
return {};
}
const auto &DL = GEP->getModule()->getDataLayout();
- if (!isDereferenceablePointer(GEP, DL)) {
+ if (!isDereferenceablePointer(GEP, LoadI->getType(), DL)) {
LLVM_DEBUG(dbgs() << "not dereferenceable\n");
// We need to make sure that we can do comparison in any order, so we
// require memory to be unconditionnally dereferencable.
diff --git a/llvm/lib/Transforms/Scalar/SROA.cpp b/llvm/lib/Transforms/Scalar/SROA.cpp
index cc79afd..33f90d0 100644
--- a/llvm/lib/Transforms/Scalar/SROA.cpp
+++ b/llvm/lib/Transforms/Scalar/SROA.cpp
@@ -1190,12 +1190,16 @@
/// FIXME: This should be hoisted into a generic utility, likely in
/// Transforms/Util/Local.h
static bool isSafePHIToSpeculate(PHINode &PN) {
+ const DataLayout &DL = PN.getModule()->getDataLayout();
+
// For now, we can only do this promotion if the load is in the same block
// as the PHI, and if there are no stores between the phi and load.
// TODO: Allow recursive phi users.
// TODO: Allow stores.
BasicBlock *BB = PN.getParent();
unsigned MaxAlign = 0;
+ uint64_t APWidth = DL.getIndexTypeSizeInBits(PN.getType());
+ APInt MaxSize(APWidth, 0);
bool HaveLoad = false;
for (User *U : PN.users()) {
LoadInst *LI = dyn_cast<LoadInst>(U);
@@ -1214,15 +1218,15 @@
if (BBI->mayWriteToMemory())
return false;
+ uint64_t Size = DL.getTypeStoreSizeInBits(LI->getType());
MaxAlign = std::max(MaxAlign, LI->getAlignment());
+ MaxSize = MaxSize.ult(Size) ? APInt(APWidth, Size) : MaxSize;
HaveLoad = true;
}
if (!HaveLoad)
return false;
- const DataLayout &DL = PN.getModule()->getDataLayout();
-
// We can only transform this if it is safe to push the loads into the
// predecessor blocks. The only thing to watch out for is that we can't put
// a possibly trapping load in the predecessor if it is a critical edge.
@@ -1244,7 +1248,7 @@
// If this pointer is always safe to load, or if we can prove that there
// is already a load in the block, then we can move the load to the pred
// block.
- if (isSafeToLoadUnconditionally(InVal, MaxAlign, DL, TI))
+ if (isSafeToLoadUnconditionally(InVal, MaxAlign, MaxSize, DL, TI))
continue;
return false;
@@ -1334,9 +1338,11 @@
// Both operands to the select need to be dereferenceable, either
// absolutely (e.g. allocas) or at this point because we can see other
// accesses to it.
- if (!isSafeToLoadUnconditionally(TValue, LI->getAlignment(), DL, LI))
+ if (!isSafeToLoadUnconditionally(TValue, LI->getType(), LI->getAlignment(),
+ DL, LI))
return false;
- if (!isSafeToLoadUnconditionally(FValue, LI->getAlignment(), DL, LI))
+ if (!isSafeToLoadUnconditionally(FValue, LI->getType(), LI->getAlignment(),
+ DL, LI))
return false;
}
diff --git a/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp b/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp
index c3ccfde..f0b7907 100644
--- a/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp
@@ -340,7 +340,7 @@
// being loaded from.
const DataLayout &DL = L->getModule()->getDataLayout();
if (isModSet(AA->getModRefInfo(CI, MemoryLocation::get(L))) ||
- !isSafeToLoadUnconditionally(L->getPointerOperand(),
+ !isSafeToLoadUnconditionally(L->getPointerOperand(), L->getType(),
L->getAlignment(), DL, L))
return false;
}