[llvm] r319131 - This reverts commit r319096 and r319097.
Rafael Espindola via llvm-commits
llvm-commits at lists.llvm.org
Mon Nov 27 17:25:38 PST 2017
Author: rafael
Date: Mon Nov 27 17:25:38 2017
New Revision: 319131
URL: http://llvm.org/viewvc/llvm-project?rev=319131&view=rev
Log:
This reverts commit r319096 and r319097.
Revert "[SROA] Propagate !range metadata when moving loads."
Revert "[Mem2Reg] Clang-format unformatted parts of this file. NFCI."
Davide says they broke a bot.
Modified:
llvm/trunk/lib/Transforms/Scalar/SROA.cpp
llvm/trunk/lib/Transforms/Utils/Local.cpp
llvm/trunk/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
llvm/trunk/test/Transforms/SROA/preserve-nonnull.ll
Modified: llvm/trunk/lib/Transforms/Scalar/SROA.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/SROA.cpp?rev=319131&r1=319130&r2=319131&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/SROA.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/SROA.cpp Mon Nov 27 17:25:38 2017
@@ -2455,10 +2455,15 @@ private:
// are different types, for example by mapping !nonnull metadata to
// !range metadata by modeling the null pointer constant converted to the
// integer type.
+ // FIXME: Add support for range metadata here. Currently the utilities
+ // for this don't propagate range metadata in trivial cases from one
+ // integer load to another, don't handle non-addrspace-0 null pointers
+ // correctly, and don't have any support for mapping ranges as the
+ // integer type becomes winder or narrower.
if (MDNode *N = LI.getMetadata(LLVMContext::MD_nonnull))
copyNonnullMetadata(LI, N, *NewLI);
- if (MDNode *N = LI.getMetadata(LLVMContext::MD_range))
- copyRangeMetadata(DL, LI, N, *NewLI);
+
+ // Try to preserve nonnull metadata
V = NewLI;
// If this is an integer load past the end of the slice (which means the
@@ -3649,7 +3654,7 @@ bool SROA::presplitLoadsAndStores(Alloca
PartPtrTy, BasePtr->getName() + "."),
getAdjustedAlignment(LI, PartOffset, DL), /*IsVolatile*/ false,
LI->getName());
- PLoad->copyMetadata(*LI, LLVMContext::MD_mem_parallel_loop_access);
+ PLoad->copyMetadata(*LI, LLVMContext::MD_mem_parallel_loop_access);
// Append this load onto the list of split loads so we can find it later
// to rewrite the stores.
Modified: llvm/trunk/lib/Transforms/Utils/Local.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/Local.cpp?rev=319131&r1=319130&r2=319131&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/Local.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/Local.cpp Mon Nov 27 17:25:38 2017
@@ -1947,24 +1947,18 @@ void llvm::copyNonnullMetadata(const Loa
void llvm::copyRangeMetadata(const DataLayout &DL, const LoadInst &OldLI,
MDNode *N, LoadInst &NewLI) {
auto *NewTy = NewLI.getType();
- auto *OldTy = OldLI.getType();
- if (DL.getTypeStoreSizeInBits(NewTy) == DL.getTypeSizeInBits(OldTy) &&
- NewTy->isIntegerTy()) {
- // An integer with the same number of bits - give it the range
- // metadata!.
- NewLI.setMetadata(LLVMContext::MD_range, N);
+ // Give up unless it is converted to a pointer where there is a single very
+ // valuable mapping we can do reliably.
+ // FIXME: It would be nice to propagate this in more ways, but the type
+ // conversions make it hard.
+ if (!NewTy->isPointerTy())
return;
- }
- if (NewTy->isPointerTy()) {
- // Try to convert the !range metadata to !nonnull metadata on the
- // new pointer.
- unsigned BitWidth = DL.getTypeSizeInBits(NewTy);
- if (!getConstantRangeFromMetadata(*N).contains(APInt(BitWidth, 0))) {
- MDNode *NN = MDNode::get(OldLI.getContext(), None);
- NewLI.setMetadata(LLVMContext::MD_nonnull, NN);
- }
+ unsigned BitWidth = DL.getTypeSizeInBits(NewTy);
+ if (!getConstantRangeFromMetadata(*N).contains(APInt(BitWidth, 0))) {
+ MDNode *NN = MDNode::get(OldLI.getContext(), None);
+ NewLI.setMetadata(LLVMContext::MD_nonnull, NN);
}
}
Modified: llvm/trunk/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/PromoteMemoryToRegister.cpp?rev=319131&r1=319130&r2=319131&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/PromoteMemoryToRegister.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/PromoteMemoryToRegister.cpp Mon Nov 27 17:25:38 2017
@@ -17,7 +17,6 @@
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/Optional.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
@@ -49,7 +48,7 @@
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#include <algorithm>
-
+#include <cassert>
#include <iterator>
#include <utility>
#include <vector>
@@ -178,16 +177,6 @@ public:
ValVector Values;
};
-/// \brief Semi-open interval of instructions that are guaranteed to
-/// all execute if the first one does.
-class GuaranteedExecutionRange {
-public:
- unsigned Start;
- unsigned End;
-
- GuaranteedExecutionRange(unsigned S, unsigned E) : Start(S), End(E) {}
-};
-
/// \brief This assigns and keeps a per-bb relative ordering of load/store
/// instructions in the block that directly load or store an alloca.
///
@@ -201,108 +190,14 @@ class LargeBlockInfo {
/// the block.
DenseMap<const Instruction *, unsigned> InstNumbers;
- /// \brief For each basic block we track, keep track of the intervals
- /// of instruction numbers of instructions that transfer control
- /// to their successors, for propagating metadata.
- DenseMap<const BasicBlock *,
- Optional<SmallVector<GuaranteedExecutionRange, 4>>>
- GuaranteedExecutionIntervals;
-
public:
- /// This code looks for stores to allocas, and for loads both for
- /// allocas and for transferring metadata.
+
+ /// This code only looks at accesses to allocas.
static bool isInterestingInstruction(const Instruction *I) {
- return isa<LoadInst>(I) ||
+ return (isa<LoadInst>(I) && isa<AllocaInst>(I->getOperand(0))) ||
(isa<StoreInst>(I) && isa<AllocaInst>(I->getOperand(1)));
}
- /// Compute the GuaranteedExecutionIntervals for a given BB.
- ///
- /// This is valid and remains valid as long as each interesting
- /// instruction (see isInterestingInstruction) that
- /// A) existed when this LBI was cleared
- /// B) has not been deleted (deleting interesting instructions is fine)
- /// are run in the same program executions and in the same order
- /// as when this LBI was cleared.
- ///
- /// Because `PromoteMemoryToRegister` does not move memory loads at
- /// all, this assumption is satisfied in this pass.
- SmallVector<GuaranteedExecutionRange, 4> computeGEI(const BasicBlock *BB) {
- SmallVector<GuaranteedExecutionRange, 4> GuaranteedExecutionIntervals;
-
- unsigned InstNo = 0;
- bool InRange = false;
- unsigned FirstInstInRange = 0;
- for (const Instruction &BBI : *BB) {
- if (isGuaranteedToTransferExecutionToSuccessor(&BBI)) {
- if (!InRange && isInterestingInstruction(&BBI)) {
- InRange = true;
- FirstInstInRange = InstNo;
- }
- } else {
- if (InRange) {
- assert(FirstInstInRange < InstNo &&
- "Can't push an empty range here.");
- GuaranteedExecutionIntervals.emplace_back(FirstInstInRange, InstNo);
- }
- InRange = false;
- }
-
- if (isInterestingInstruction(&BBI)) {
- auto It = InstNumbers.find(&BBI);
- assert(It != InstNumbers.end() && InstNo <= It->second &&
- "missing number for interesting instruction");
- InstNo = It->second + 1;
- }
- }
-
- if (InRange) {
- assert(FirstInstInRange < InstNo && "Can't push an empty range here.");
- GuaranteedExecutionIntervals.emplace_back(FirstInstInRange, InstNo);
- }
-
- return GuaranteedExecutionIntervals;
- }
-
- /// Return true if, when CxtI executes, it is guaranteed that either
- /// I had executed already or that I is guaranteed to be later executed.
- ///
- /// The useful property this guarantees is that if I exhibits undefined
- /// behavior under some circumstances, then the whole program will exhibit
- /// undefined behavior at CxtI.
- bool isGuaranteedToBeExecuted(const Instruction *CxtI, const Instruction *I) {
- const BasicBlock *BB = CxtI->getParent();
-
- if (BB != I->getParent()) {
- // Instructions in different basic blocks, so control flow
- // can diverge between them (we could track this with
- // postdoms, but we don't bother).
- return false;
- }
-
- unsigned Index1 = getInstructionIndex(CxtI);
- unsigned Index2 = getInstructionIndex(I);
-
- auto &BBGEI = GuaranteedExecutionIntervals[BB];
- if (!BBGEI.hasValue()) {
- BBGEI.emplace(computeGEI(BB));
- }
-
- // We want to check whether I and CxtI are in the same range. To do that,
- // we notice that CxtI can only be in the first range R where
- // CxtI.end < R.end. If we find that range using binary search,
- // we can check whether I and CxtI are both in it.
- GuaranteedExecutionRange Bound(Index1, Index1);
- auto R = std::upper_bound(
- BBGEI->begin(), BBGEI->end(), Bound,
- [](GuaranteedExecutionRange I_, GuaranteedExecutionRange R) {
- return I_.End < R.End;
- });
-
- return R != BBGEI->end() && R->Start <= Index1 && Index1 < R->End &&
- R->Start <= Index2 && Index2 < R->End;
- }
-
/// Get or calculate the index of the specified instruction.
unsigned getInstructionIndex(const Instruction *I) {
assert(isInterestingInstruction(I) &&
@@ -318,11 +213,9 @@ public:
// avoid gratuitus rescans.
const BasicBlock *BB = I->getParent();
unsigned InstNo = 0;
- GuaranteedExecutionIntervals.erase(BB);
for (const Instruction &BBI : *BB)
if (isInterestingInstruction(&BBI))
InstNumbers[&BBI] = InstNo++;
-
It = InstNumbers.find(I);
assert(It != InstNumbers.end() && "Didn't insert instruction?");
@@ -331,10 +224,7 @@ public:
void deleteValue(const Instruction *I) { InstNumbers.erase(I); }
- void clear() {
- InstNumbers.clear();
- GuaranteedExecutionIntervals.clear();
- }
+ void clear() { InstNumbers.clear(); }
};
struct PromoteMem2Reg {
@@ -412,7 +302,7 @@ private:
const SmallPtrSetImpl<BasicBlock *> &DefBlocks,
SmallPtrSetImpl<BasicBlock *> &LiveInBlocks);
void RenamePass(BasicBlock *BB, BasicBlock *Pred,
- RenamePassData::ValVector &IncVals, LargeBlockInfo &LBI,
+ RenamePassData::ValVector &IncVals,
std::vector<RenamePassData> &Worklist);
bool QueuePhiNode(BasicBlock *BB, unsigned AllocaIdx, unsigned &Version);
};
@@ -431,29 +321,6 @@ static void addAssumeNonNull(AssumptionC
AC->registerAssumption(CI);
}
-static void addAssumptionsFromMetadata(LoadInst *LI, Value *ReplVal,
- DominatorTree &DT, const DataLayout &DL,
- LargeBlockInfo &LBI,
- AssumptionCache *AC) {
- if (LI->getMetadata(LLVMContext::MD_nonnull) &&
- !isKnownNonZero(ReplVal, DL, 0, AC, LI, &DT)) {
- addAssumeNonNull(AC, LI);
- }
-
- if (auto *N = LI->getMetadata(LLVMContext::MD_range)) {
- // Range metadata is harder to use as an assumption,
- // so don't try to add one, but *do* try to copy
- // the metadata to a load in the same BB.
- if (LoadInst *NewLI = dyn_cast<LoadInst>(ReplVal)) {
- DEBUG(dbgs() << "trying to move !range metadata from" << *LI << " to"
- << *NewLI << "\n");
- if (LBI.isGuaranteedToBeExecuted(LI, NewLI)) {
- copyRangeMetadata(DL, *LI, N, *NewLI);
- }
- }
- }
-}
-
static void removeLifetimeIntrinsicUsers(AllocaInst *AI) {
// Knowing that this alloca is promotable, we know that it's safe to kill all
// instructions except for load and store.
@@ -542,7 +409,9 @@ static bool rewriteSingleStoreAlloca(All
// If the load was marked as nonnull we don't want to lose
// that information when we erase this Load. So we preserve
// it with an assume.
- addAssumptionsFromMetadata(LI, ReplVal, DT, DL, LBI, AC);
+ if (AC && LI->getMetadata(LLVMContext::MD_nonnull) &&
+ !isKnownNonZero(ReplVal, DL, 0, AC, LI, &DT))
+ addAssumeNonNull(AC, LI);
LI->replaceAllUsesWith(ReplVal);
LI->eraseFromParent();
@@ -636,7 +505,9 @@ static bool promoteSingleBlockAlloca(All
// Note, if the load was marked as nonnull we don't want to lose that
// information when we erase it. So we preserve it with an assume.
Value *ReplVal = std::prev(I)->second->getOperand(0);
- addAssumptionsFromMetadata(LI, ReplVal, DT, DL, LBI, AC);
+ if (AC && LI->getMetadata(LLVMContext::MD_nonnull) &&
+ !isKnownNonZero(ReplVal, DL, 0, AC, LI, &DT))
+ addAssumeNonNull(AC, LI);
LI->replaceAllUsesWith(ReplVal);
}
@@ -772,6 +643,7 @@ void PromoteMem2Reg::run() {
if (Allocas.empty())
return; // All of the allocas must have been trivial!
+
LBI.clear();
// Set the incoming values for the basic block to be null values for all of
@@ -789,10 +661,9 @@ void PromoteMem2Reg::run() {
RenamePassData RPD = std::move(RenamePassWorkList.back());
RenamePassWorkList.pop_back();
// RenamePass may add new worklist entries.
- RenamePass(RPD.BB, RPD.Pred, RPD.Values, LBI, RenamePassWorkList);
+ RenamePass(RPD.BB, RPD.Pred, RPD.Values, RenamePassWorkList);
} while (!RenamePassWorkList.empty());
- LBI.clear();
// The renamer uses the Visited set to avoid infinite loops. Clear it now.
Visited.clear();
@@ -1004,7 +875,6 @@ bool PromoteMem2Reg::QueuePhiNode(BasicB
/// predecessor block Pred.
void PromoteMem2Reg::RenamePass(BasicBlock *BB, BasicBlock *Pred,
RenamePassData::ValVector &IncomingVals,
- LargeBlockInfo &LBI,
std::vector<RenamePassData> &Worklist) {
NextIteration:
// If we are inserting any phi nodes into this BB, they will already be in the
@@ -1071,12 +941,13 @@ NextIteration:
// If the load was marked as nonnull we don't want to lose
// that information when we erase this Load. So we preserve
// it with an assume.
- addAssumptionsFromMetadata(LI, V, DT, SQ.DL, LBI, AC);
+ if (AC && LI->getMetadata(LLVMContext::MD_nonnull) &&
+ !isKnownNonZero(V, SQ.DL, 0, AC, LI, &DT))
+ addAssumeNonNull(AC, LI);
// Anything using the load now uses the current value.
LI->replaceAllUsesWith(V);
BB->getInstList().erase(LI);
- LBI.deleteValue(LI);
} else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
// Delete this instruction and mark the name as the current holder of the
// value
@@ -1094,7 +965,6 @@ NextIteration:
for (DbgInfoIntrinsic *DII : AllocaDbgDeclares[ai->second])
ConvertDebugDeclareToDebugValue(DII, SI, DIB);
BB->getInstList().erase(SI);
- LBI.deleteValue(SI);
}
}
Modified: llvm/trunk/test/Transforms/SROA/preserve-nonnull.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SROA/preserve-nonnull.ll?rev=319131&r1=319130&r2=319131&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/SROA/preserve-nonnull.ll (original)
+++ llvm/trunk/test/Transforms/SROA/preserve-nonnull.ll Mon Nov 27 17:25:38 2017
@@ -3,8 +3,6 @@
; Make sure that SROA doesn't lose nonnull metadata
; on loads from allocas that get optimized out.
-%pair = type { i64, [0 x i64], [1 x i64] }
-
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i32, i1)
; Check that we do basic propagation of nonnull when rewriting.
@@ -44,23 +42,6 @@ entry:
ret float* %ret
}
-; Make sure we propagate the !range attribute when we expand loads.
-define i64 @propagate_range(%pair* dereferenceable(16)) {
-; CHECK-LABEL: define i64 @propagate_range(
-; CHECK-NEXT: start:
-; CHECK-NEXT: %[[SROA_IDX:.*]] = getelementptr inbounds %pair
-; CHECK-NEXT: %[[RESULT:.*]] = load i64, i64* %[[SROA_IDX]], align 8, !range !1
-; CHECK: ret i64 %[[RESULT]]
-start:
- %a = alloca %pair
- %1 = bitcast %pair* %0 to i8*
- %2 = bitcast %pair* %a to i8*
- call void @llvm.memcpy.p0i8.p0i8.i64(i8* %2, i8* %1, i64 16, i32 8, i1 false)
- %3 = getelementptr inbounds %pair, %pair* %a, i32 0, i32 0
- %4 = load i64, i64* %3, !range !1
- ret i64 %4
-}
-
; Make sure we properly handle the !nonnull attribute when we convert
; a pointer load to an integer load.
; FIXME: While this doesn't do anythnig actively harmful today, it really
@@ -109,4 +90,3 @@ entry:
}
!0 = !{}
-!1 = !{i64 0, i64 2}
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