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-rw-r--r--contrib/llvm-project/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp118
1 files changed, 70 insertions, 48 deletions
diff --git a/contrib/llvm-project/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/contrib/llvm-project/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
index c7e9c919ec47..86bbb6a889e6 100644
--- a/contrib/llvm-project/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
+++ b/contrib/llvm-project/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
@@ -62,10 +62,6 @@ STATISTIC(NumDeadAlloca, "Number of dead alloca's removed");
STATISTIC(NumPHIInsert, "Number of PHI nodes inserted");
bool llvm::isAllocaPromotable(const AllocaInst *AI) {
- // FIXME: If the memory unit is of pointer or integer type, we can permit
- // assignments to subsections of the memory unit.
- unsigned AS = AI->getType()->getAddressSpace();
-
// Only allow direct and non-volatile loads and stores...
for (const User *U : AI->users()) {
if (const LoadInst *LI = dyn_cast<LoadInst>(U)) {
@@ -81,19 +77,18 @@ bool llvm::isAllocaPromotable(const AllocaInst *AI) {
if (SI->isVolatile())
return false;
} else if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(U)) {
- if (!II->isLifetimeStartOrEnd())
+ if (!II->isLifetimeStartOrEnd() && !II->isDroppable())
return false;
} else if (const BitCastInst *BCI = dyn_cast<BitCastInst>(U)) {
- if (BCI->getType() != Type::getInt8PtrTy(U->getContext(), AS))
- return false;
- if (!onlyUsedByLifetimeMarkers(BCI))
+ if (!onlyUsedByLifetimeMarkersOrDroppableInsts(BCI))
return false;
} else if (const GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(U)) {
- if (GEPI->getType() != Type::getInt8PtrTy(U->getContext(), AS))
- return false;
if (!GEPI->hasAllZeroIndices())
return false;
- if (!onlyUsedByLifetimeMarkers(GEPI))
+ if (!onlyUsedByLifetimeMarkersOrDroppableInsts(GEPI))
+ return false;
+ } else if (const AddrSpaceCastInst *ASCI = dyn_cast<AddrSpaceCastInst>(U)) {
+ if (!onlyUsedByLifetimeMarkers(ASCI))
return false;
} else {
return false;
@@ -106,6 +101,8 @@ bool llvm::isAllocaPromotable(const AllocaInst *AI) {
namespace {
struct AllocaInfo {
+ using DbgUserVec = SmallVector<DbgVariableIntrinsic *, 1>;
+
SmallVector<BasicBlock *, 32> DefiningBlocks;
SmallVector<BasicBlock *, 32> UsingBlocks;
@@ -113,7 +110,7 @@ struct AllocaInfo {
BasicBlock *OnlyBlock;
bool OnlyUsedInOneBlock;
- TinyPtrVector<DbgVariableIntrinsic *> DbgDeclares;
+ DbgUserVec DbgUsers;
void clear() {
DefiningBlocks.clear();
@@ -121,7 +118,7 @@ struct AllocaInfo {
OnlyStore = nullptr;
OnlyBlock = nullptr;
OnlyUsedInOneBlock = true;
- DbgDeclares.clear();
+ DbgUsers.clear();
}
/// Scan the uses of the specified alloca, filling in the AllocaInfo used
@@ -132,8 +129,8 @@ struct AllocaInfo {
// As we scan the uses of the alloca instruction, keep track of stores,
// and decide whether all of the loads and stores to the alloca are within
// the same basic block.
- for (auto UI = AI->user_begin(), E = AI->user_end(); UI != E;) {
- Instruction *User = cast<Instruction>(*UI++);
+ for (User *U : AI->users()) {
+ Instruction *User = cast<Instruction>(U);
if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
// Remember the basic blocks which define new values for the alloca
@@ -154,7 +151,7 @@ struct AllocaInfo {
}
}
- DbgDeclares = FindDbgAddrUses(AI);
+ findDbgUsers(DbgUsers, AI);
}
};
@@ -252,7 +249,7 @@ struct PromoteMem2Reg {
/// For each alloca, we keep track of the dbg.declare intrinsic that
/// describes it, if any, so that we can convert it to a dbg.value
/// intrinsic if the alloca gets promoted.
- SmallVector<TinyPtrVector<DbgVariableIntrinsic *>, 8> AllocaDbgDeclares;
+ SmallVector<AllocaInfo::DbgUserVec, 8> AllocaDbgUsers;
/// The set of basic blocks the renamer has already visited.
SmallPtrSet<BasicBlock *, 16> Visited;
@@ -312,23 +309,37 @@ static void addAssumeNonNull(AssumptionCache *AC, LoadInst *LI) {
AC->registerAssumption(CI);
}
-static void removeLifetimeIntrinsicUsers(AllocaInst *AI) {
+static void removeIntrinsicUsers(AllocaInst *AI) {
// Knowing that this alloca is promotable, we know that it's safe to kill all
// instructions except for load and store.
- for (auto UI = AI->user_begin(), UE = AI->user_end(); UI != UE;) {
- Instruction *I = cast<Instruction>(*UI);
+ for (auto UI = AI->use_begin(), UE = AI->use_end(); UI != UE;) {
+ Instruction *I = cast<Instruction>(UI->getUser());
+ Use &U = *UI;
++UI;
if (isa<LoadInst>(I) || isa<StoreInst>(I))
continue;
+ // Drop the use of AI in droppable instructions.
+ if (I->isDroppable()) {
+ I->dropDroppableUse(U);
+ continue;
+ }
+
if (!I->getType()->isVoidTy()) {
// The only users of this bitcast/GEP instruction are lifetime intrinsics.
// Follow the use/def chain to erase them now instead of leaving it for
// dead code elimination later.
- for (auto UUI = I->user_begin(), UUE = I->user_end(); UUI != UUE;) {
- Instruction *Inst = cast<Instruction>(*UUI);
+ for (auto UUI = I->use_begin(), UUE = I->use_end(); UUI != UUE;) {
+ Instruction *Inst = cast<Instruction>(UUI->getUser());
+ Use &UU = *UUI;
++UUI;
+
+ // Drop the use of I in droppable instructions.
+ if (Inst->isDroppable()) {
+ Inst->dropDroppableUse(UU);
+ continue;
+ }
Inst->eraseFromParent();
}
}
@@ -355,8 +366,8 @@ static bool rewriteSingleStoreAlloca(AllocaInst *AI, AllocaInfo &Info,
// Clear out UsingBlocks. We will reconstruct it here if needed.
Info.UsingBlocks.clear();
- for (auto UI = AI->user_begin(), E = AI->user_end(); UI != E;) {
- Instruction *UserInst = cast<Instruction>(*UI++);
+ for (User *U : make_early_inc_range(AI->users())) {
+ Instruction *UserInst = cast<Instruction>(U);
if (UserInst == OnlyStore)
continue;
LoadInst *LI = cast<LoadInst>(UserInst);
@@ -412,10 +423,14 @@ static bool rewriteSingleStoreAlloca(AllocaInst *AI, AllocaInfo &Info,
// Record debuginfo for the store and remove the declaration's
// debuginfo.
- for (DbgVariableIntrinsic *DII : Info.DbgDeclares) {
- DIBuilder DIB(*AI->getModule(), /*AllowUnresolved*/ false);
- ConvertDebugDeclareToDebugValue(DII, Info.OnlyStore, DIB);
- DII->eraseFromParent();
+ for (DbgVariableIntrinsic *DII : Info.DbgUsers) {
+ if (DII->isAddressOfVariable()) {
+ DIBuilder DIB(*AI->getModule(), /*AllowUnresolved*/ false);
+ ConvertDebugDeclareToDebugValue(DII, Info.OnlyStore, DIB);
+ DII->eraseFromParent();
+ } else if (DII->getExpression()->startsWithDeref()) {
+ DII->eraseFromParent();
+ }
}
// Remove the (now dead) store and alloca.
Info.OnlyStore->eraseFromParent();
@@ -465,8 +480,8 @@ static bool promoteSingleBlockAlloca(AllocaInst *AI, const AllocaInfo &Info,
// Walk all of the loads from this alloca, replacing them with the nearest
// store above them, if any.
- for (auto UI = AI->user_begin(), E = AI->user_end(); UI != E;) {
- LoadInst *LI = dyn_cast<LoadInst>(*UI++);
+ for (User *U : make_early_inc_range(AI->users())) {
+ LoadInst *LI = dyn_cast<LoadInst>(U);
if (!LI)
continue;
@@ -510,9 +525,11 @@ static bool promoteSingleBlockAlloca(AllocaInst *AI, const AllocaInfo &Info,
while (!AI->use_empty()) {
StoreInst *SI = cast<StoreInst>(AI->user_back());
// Record debuginfo for the store before removing it.
- for (DbgVariableIntrinsic *DII : Info.DbgDeclares) {
- DIBuilder DIB(*AI->getModule(), /*AllowUnresolved*/ false);
- ConvertDebugDeclareToDebugValue(DII, SI, DIB);
+ for (DbgVariableIntrinsic *DII : Info.DbgUsers) {
+ if (DII->isAddressOfVariable()) {
+ DIBuilder DIB(*AI->getModule(), /*AllowUnresolved*/ false);
+ ConvertDebugDeclareToDebugValue(DII, SI, DIB);
+ }
}
SI->eraseFromParent();
LBI.deleteValue(SI);
@@ -521,8 +538,9 @@ static bool promoteSingleBlockAlloca(AllocaInst *AI, const AllocaInfo &Info,
AI->eraseFromParent();
// The alloca's debuginfo can be removed as well.
- for (DbgVariableIntrinsic *DII : Info.DbgDeclares)
- DII->eraseFromParent();
+ for (DbgVariableIntrinsic *DII : Info.DbgUsers)
+ if (DII->isAddressOfVariable() || DII->getExpression()->startsWithDeref())
+ DII->eraseFromParent();
++NumLocalPromoted;
return true;
@@ -531,7 +549,7 @@ static bool promoteSingleBlockAlloca(AllocaInst *AI, const AllocaInfo &Info,
void PromoteMem2Reg::run() {
Function &F = *DT.getRoot()->getParent();
- AllocaDbgDeclares.resize(Allocas.size());
+ AllocaDbgUsers.resize(Allocas.size());
AllocaInfo Info;
LargeBlockInfo LBI;
@@ -544,7 +562,7 @@ void PromoteMem2Reg::run() {
assert(AI->getParent()->getParent() == &F &&
"All allocas should be in the same function, which is same as DF!");
- removeLifetimeIntrinsicUsers(AI);
+ removeIntrinsicUsers(AI);
if (AI->use_empty()) {
// If there are no uses of the alloca, just delete it now.
@@ -589,8 +607,8 @@ void PromoteMem2Reg::run() {
}
// Remember the dbg.declare intrinsic describing this alloca, if any.
- if (!Info.DbgDeclares.empty())
- AllocaDbgDeclares[AllocaNum] = Info.DbgDeclares;
+ if (!Info.DbgUsers.empty())
+ AllocaDbgUsers[AllocaNum] = Info.DbgUsers;
// Keep the reverse mapping of the 'Allocas' array for the rename pass.
AllocaLookup[Allocas[AllocaNum]] = AllocaNum;
@@ -663,9 +681,11 @@ void PromoteMem2Reg::run() {
}
// Remove alloca's dbg.declare instrinsics from the function.
- for (auto &Declares : AllocaDbgDeclares)
- for (auto *DII : Declares)
- DII->eraseFromParent();
+ for (auto &DbgUsers : AllocaDbgUsers) {
+ for (auto *DII : DbgUsers)
+ if (DII->isAddressOfVariable() || DII->getExpression()->startsWithDeref())
+ DII->eraseFromParent();
+ }
// Loop over all of the PHI nodes and see if there are any that we can get
// rid of because they merge all of the same incoming values. This can
@@ -720,7 +740,7 @@ void PromoteMem2Reg::run() {
continue;
// Get the preds for BB.
- SmallVector<BasicBlock *, 16> Preds(pred_begin(BB), pred_end(BB));
+ SmallVector<BasicBlock *, 16> Preds(predecessors(BB));
// Ok, now we know that all of the PHI nodes are missing entries for some
// basic blocks. Start by sorting the incoming predecessors for efficient
@@ -887,7 +907,7 @@ NextIteration:
// operands so far. Remember this count.
unsigned NewPHINumOperands = APN->getNumOperands();
- unsigned NumEdges = std::count(succ_begin(Pred), succ_end(Pred), BB);
+ unsigned NumEdges = llvm::count(successors(Pred), BB);
assert(NumEdges && "Must be at least one edge from Pred to BB!");
// Add entries for all the phis.
@@ -905,8 +925,9 @@ NextIteration:
// The currently active variable for this block is now the PHI.
IncomingVals[AllocaNo] = APN;
- for (DbgVariableIntrinsic *DII : AllocaDbgDeclares[AllocaNo])
- ConvertDebugDeclareToDebugValue(DII, APN, DIB);
+ for (DbgVariableIntrinsic *DII : AllocaDbgUsers[AllocaNo])
+ if (DII->isAddressOfVariable())
+ ConvertDebugDeclareToDebugValue(DII, APN, DIB);
// Get the next phi node.
++PNI;
@@ -965,8 +986,9 @@ NextIteration:
// Record debuginfo for the store before removing it.
IncomingLocs[AllocaNo] = SI->getDebugLoc();
- for (DbgVariableIntrinsic *DII : AllocaDbgDeclares[ai->second])
- ConvertDebugDeclareToDebugValue(DII, SI, DIB);
+ for (DbgVariableIntrinsic *DII : AllocaDbgUsers[ai->second])
+ if (DII->isAddressOfVariable())
+ ConvertDebugDeclareToDebugValue(DII, SI, DIB);
BB->getInstList().erase(SI);
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-01 06:35:53 +0000