// Set up the preheader to have a definition of the value. It is the live-out
// value from the preheader that uses in the loop will use.
- LoadInst *PreheaderLoad = new LoadInst(
- AccessTy, SomePtr, SomePtr->getName() + ".promoted",
- Preheader->getTerminator());
- if (SawUnorderedAtomic)
- PreheaderLoad->setOrdering(AtomicOrdering::Unordered);
- PreheaderLoad->setAlignment(Alignment);
- PreheaderLoad->setDebugLoc(DebugLoc());
- if (AATags)
- PreheaderLoad->setAAMetadata(AATags);
- SSA.AddAvailableValue(Preheader, PreheaderLoad);
-
- MemoryAccess *PreheaderLoadMemoryAccess = MSSAU.createMemoryAccessInBB(
- PreheaderLoad, nullptr, PreheaderLoad->getParent(), MemorySSA::End);
- MemoryUse *NewMemUse = cast<MemoryUse>(PreheaderLoadMemoryAccess);
- MSSAU.insertUse(NewMemUse, /*RenameUses=*/true);
+ LoadInst *PreheaderLoad = nullptr;
+ if (FoundLoadToPromote) {
+ PreheaderLoad =
+ new LoadInst(AccessTy, SomePtr, SomePtr->getName() + ".promoted",
+ Preheader->getTerminator());
+ if (SawUnorderedAtomic)
+ PreheaderLoad->setOrdering(AtomicOrdering::Unordered);
+ PreheaderLoad->setAlignment(Alignment);
+ PreheaderLoad->setDebugLoc(DebugLoc());
+ if (AATags)
+ PreheaderLoad->setAAMetadata(AATags);
+
+ MemoryAccess *PreheaderLoadMemoryAccess = MSSAU.createMemoryAccessInBB(
+ PreheaderLoad, nullptr, PreheaderLoad->getParent(), MemorySSA::End);
+ MemoryUse *NewMemUse = cast<MemoryUse>(PreheaderLoadMemoryAccess);
+ MSSAU.insertUse(NewMemUse, /*RenameUses=*/true);
+ SSA.AddAvailableValue(Preheader, PreheaderLoad);
+ }
if (VerifyMemorySSA)
MSSAU.getMemorySSA()->verifyMemorySSA();
if (VerifyMemorySSA)
MSSAU.getMemorySSA()->verifyMemorySSA();
// If the SSAUpdater didn't use the load in the preheader, just zap it now.
- if (PreheaderLoad->use_empty())
+ if (PreheaderLoad && PreheaderLoad->use_empty())
eraseInstruction(*PreheaderLoad, *SafetyInfo, MSSAU);
return true;
define void @test_sink_store_only() writeonly {
; CHECK-LABEL: @test_sink_store_only(
; CHECK-NEXT: entry:
-; CHECK-NEXT: [[GLB_PROMOTED:%.*]] = load i8, i8* @glb, align 1
; CHECK-NEXT: br label [[LOOP_HEADER:%.*]]
; CHECK: loop.header:
-; CHECK-NEXT: [[DIV1:%.*]] = phi i8 [ [[GLB_PROMOTED]], [[ENTRY:%.*]] ], [ [[DIV:%.*]], [[LOOP_LATCH:%.*]] ]
+; CHECK-NEXT: [[DIV1:%.*]] = phi i8 [ undef, [[ENTRY:%.*]] ], [ [[DIV:%.*]], [[LOOP_LATCH:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i8 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[LOOP_LATCH]] ]
; CHECK-NEXT: [[CMP:%.*]] = icmp ult i8 [[I]], 4
; CHECK-NEXT: br i1 [[CMP]], label [[LOOP_LATCH]], label [[EXIT:%.*]]