[MemCpyOpt] lifetime markers reconstruction for Stack-move optimization #68990
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode characters
khei4 force-pushed the perf/stack-move-multi-bb-lifetime-spans branch from 3c85b97 to f4781f1 Compare 
Member
| @llvm/pr-subscribers-llvm-transforms Author: Kohei Asano (khei4) ChangesFixes #66403 This patch did two things for the stack-move optimization reduction pattern.
Patch is 25.72 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/68990.diff 3 Files Affected:
diff --git a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp index 688bcfa57158975..7e5cdd76ef514da 100644 --- a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp +++ b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp @@ -1424,6 +1424,46 @@ bool MemCpyOptPass::performMemCpyToMemSetOptzn(MemCpyInst *MemCpy, return true; } +namespace { + +using InsertionPt = PointerUnion<Instruction *, BasicBlock *>; +/// Find the nearest Instruction or BasicBlock that dominates both I1 and +/// I2. +static InsertionPt findNearestCommonDominator(InsertionPt I1, InsertionPt I2, + DominatorTree *DT) { + auto GetParent = [](InsertionPt I) { + if (auto *BB = dyn_cast<BasicBlock *>(I)) + return BB; + return cast<Instruction *>(I)->getParent(); + }; + BasicBlock *BB1 = GetParent(I1); + BasicBlock *BB2 = GetParent(I2); + if (BB1 == BB2) { + // BasicBlock InsertionPt means the terminator. + if (isa<BasicBlock *>(I1)) + return I2; + if (isa<BasicBlock *>(I2)) + return I1; + return cast<Instruction *>(I1)->comesBefore(cast<Instruction *>(I2)) ? I1 + : I2; + } + + // These checks are necessary, because findNearestCommonDominator for NodeT + // doesn't handle these. + if (!DT->isReachableFromEntry(BB2)) + return I1; + if (!DT->isReachableFromEntry(BB1)) + return I2; + + BasicBlock *DomBB = DT->findNearestCommonDominator(BB1, BB2); + if (BB2 == DomBB) + return I2; + if (BB1 == DomBB) + return I1; + return DomBB; +} + +} // namespace // Attempts to optimize the pattern whereby memory is copied from an alloca to // another alloca, where the two allocas don't have conflicting mod/ref. If // successful, the two allocas can be merged into one and the transfer can be @@ -1466,13 +1506,27 @@ bool MemCpyOptPass::performStackMoveOptzn(Instruction *Load, Instruction *Store, return false; // Check that src and dest are never captured, unescaped allocas. Also - // find the nearest common dominator and postdominator for all users in + // find the nearest common dominator and post-dominator for all users in // order to shrink wrap the lifetimes, and instructions with noalias metadata // to remove them. SmallVector<Instruction *, 4> LifetimeMarkers; + InsertionPt StartPt = nullptr; + SmallSet<Instruction *, 4> EndPts; SmallSet<Instruction *, 4> NoAliasInstrs; bool SrcNotDom = false; + auto InsertIfNotPDom = [&](Instruction *I) { + for (auto EndPt : EndPts) { + if (PDT->dominates(EndPt, I)) + return; + else if (PDT->dominates(I, EndPt)) { + EndPt = I; + return; + } + } + EndPts.insert(I); + return; + }; // Recursively track the user and check whether modified alias exist. auto IsDereferenceableOrNull = [](Value *V, const DataLayout &DL) -> bool { @@ -1514,6 +1568,13 @@ bool MemCpyOptPass::performStackMoveOptzn(Instruction *Load, Instruction *Store, Worklist.push_back(UI); continue; case UseCaptureKind::NO_CAPTURE: { + if (!StartPt) { + StartPt = UI; + EndPts.insert(UI); + } else { + StartPt = findNearestCommonDominator(StartPt, UI, DT); + InsertIfNotPDom(UI); + } if (UI->isLifetimeStartOrEnd()) { // We note the locations of these intrinsic calls so that we can // delete them later if the optimization succeeds, this is safe @@ -1623,12 +1684,38 @@ bool MemCpyOptPass::performStackMoveOptzn(Instruction *Load, Instruction *Store, // Drop metadata on the source alloca. SrcAlloca->dropUnknownNonDebugMetadata(); - // TODO: Reconstruct merged lifetime markers. - // Remove all other lifetime markers. if the original lifetime intrinsics - // exists. + // Reconstruction of lifetime markers. + // 1. Insert new lifetime.start to the dominator for all src and dest uses. + // 2. Remove original markers except possibly last lifetime.end if (!LifetimeMarkers.empty()) { - for (Instruction *I : LifetimeMarkers) - eraseInstruction(I); + LLVMContext &C = SrcAlloca->getContext(); + IRBuilder<> Builder(C); + ConstantInt *AllocaSize = ConstantInt::get(Type::getInt64Ty(C), -1); + if (!Size.isScalable()) + AllocaSize = ConstantInt::get(Type::getInt64Ty(C), Size); + // Create a new lifetime start marker before the first user of src or alloca + // users. + MemoryAccess *StartMA; + if (auto *DomI = dyn_cast_if_present<Instruction *>(StartPt)) { + Builder.SetInsertPoint(DomI->getParent(), DomI->getIterator()); + auto *Start = Builder.CreateLifetimeStart(SrcAlloca, AllocaSize); + StartMA = MSSAU->createMemoryAccessBefore(Start, nullptr, + MSSA->getMemoryAccess(DomI)); + } else { + auto *DomB = cast<BasicBlock *>(StartPt); + Builder.SetInsertPoint(DomB->getTerminator()); + auto *Start = Builder.CreateLifetimeStart(SrcAlloca, AllocaSize); + StartMA = MSSAU->createMemoryAccessInBB( + Start, nullptr, Start->getParent(), MemorySSA::BeforeTerminator); + } + MSSAU->insertDef(cast<MemoryDef>(StartMA), /*RenameUses=*/true); + + // Remove all lifetime markers except . if the original lifetime intrinsics + // exists. + for (Instruction *I : LifetimeMarkers) { + if (EndPts.find(I) == EndPts.end()) + eraseInstruction(I); + } } // As this transformation can cause memory accesses that didn't previously diff --git a/llvm/test/Transforms/MemCpyOpt/lifetime-missing.ll b/llvm/test/Transforms/MemCpyOpt/lifetime-missing.ll index 0626f09702f7e21..e3190cee45d2da4 100644 --- a/llvm/test/Transforms/MemCpyOpt/lifetime-missing.ll +++ b/llvm/test/Transforms/MemCpyOpt/lifetime-missing.ll @@ -15,6 +15,7 @@ define void @test() { ; CHECK-NEXT: entry: ; CHECK-NEXT: [[AGG_TMP_SROA_14:%.*]] = alloca [20 x i8], align 4 ; CHECK-NEXT: [[AGG_TMP_SROA_14_128_SROA_IDX:%.*]] = getelementptr i8, ptr [[AGG_TMP_SROA_14]], i64 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[AGG_TMP_SROA_14]]) ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr [[AGG_TMP_SROA_14_128_SROA_IDX]], i8 0, i64 1, i1 false) ; CHECK-NEXT: [[AGG_TMP3_SROA_35_128_SROA_IDX:%.*]] = getelementptr i8, ptr [[AGG_TMP_SROA_14]], i64 4 ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr inttoptr (i64 4 to ptr), i8 0, i64 1, i1 false) diff --git a/llvm/test/Transforms/MemCpyOpt/stack-move.ll b/llvm/test/Transforms/MemCpyOpt/stack-move.ll index 6089c0a4d7cf507..998b742e480bb73 100644 --- a/llvm/test/Transforms/MemCpyOpt/stack-move.ll +++ b/llvm/test/Transforms/MemCpyOpt/stack-move.ll @@ -24,9 +24,11 @@ declare i32 @use_writeonly(ptr noundef) memory(write) define void @basic_memcpy() { ; CHECK-LABEL: define void @basic_memcpy() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -67,9 +69,11 @@ define i32 @use_not_dominated_by_src_alloca() { define void @basic_memmove() { ; CHECK-LABEL: define void @basic_memmove() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -92,9 +96,11 @@ define void @basic_memmove() { define void @load_store() { ; CHECK-LABEL: define void @load_store() { ; CHECK-NEXT: [[SRC:%.*]] = alloca i32, align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr [[SRC]]) ; CHECK-NEXT: store i32 42, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca i32, align 4 @@ -118,9 +124,11 @@ define void @load_store_scalable(<vscale x 4 x i32> %x) { ; CHECK-LABEL: define void @load_store_scalable ; CHECK-SAME: (<vscale x 4 x i32> [[X:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca <vscale x 4 x i32>, align 16 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 -1, ptr [[SRC]]) ; CHECK-NEXT: store <vscale x 4 x i32> [[X]], ptr [[SRC]], align 16 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 -1, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca <vscale x 4 x i32> @@ -144,9 +152,11 @@ define void @load_store_scalable(<vscale x 4 x i32> %x) { define void @align_up() { ; CHECK-LABEL: define void @align_up() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 8 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -169,10 +179,12 @@ define void @align_up() { define void @remove_extra_lifetime_intrinsics() { ; CHECK-LABEL: define void @remove_extra_lifetime_intrinsics() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP3:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -221,11 +233,13 @@ define void @no_lifetime() { define void @alias_no_mod() { ; CHECK-LABEL: define void @alias_no_mod() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: [[DEST_ALIAS:%.*]] = getelementptr [[STRUCT_FOO]], ptr [[SRC]], i32 0, i32 0 ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[SRC_ALIAS:%.*]] = getelementptr [[STRUCT_FOO]], ptr [[SRC]], i32 0, i32 0 ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -258,9 +272,11 @@ define void @alias_no_mod() { define void @remove_scoped_noalias() { ; CHECK-LABEL: define void @remove_scoped_noalias() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]), !alias.scope !0 ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -282,9 +298,11 @@ define void @remove_scoped_noalias() { define void @remove_alloca_metadata() { ; CHECK-LABEL: define void @remove_alloca_metadata() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]), !alias.scope !0 ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4, !annotation !3 @@ -307,9 +325,11 @@ define void @remove_alloca_metadata() { define void @noalias_on_lifetime() { ; CHECK-LABEL: define void @noalias_on_lifetime() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]), !alias.scope !0 ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]), !noalias !0 ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -331,9 +351,11 @@ define void @noalias_on_lifetime() { define void @src_ref_dest_ref_after_copy() { ; CHECK-LABEL: define void @src_ref_dest_ref_after_copy() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_readonly(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_readonly(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -355,9 +377,11 @@ define void @src_ref_dest_ref_after_copy() { define void @src_mod_dest_mod_after_copy() { ; CHECK-LABEL: define void @src_mod_dest_mod_after_copy() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_writeonly(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_writeonly(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -378,6 +402,7 @@ define void @src_mod_dest_mod_after_copy() { define void @avoid_memory_use_last_user_crash() { ; CHECK-LABEL: define void @avoid_memory_use_last_user_crash() { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[SRC]], align 4 ; CHECK-NEXT: ret void @@ -396,6 +421,7 @@ define void @avoid_memory_use_last_user_crash() { define void @terminator_lastuse() personality i32 0 { ; CHECK-LABEL: define void @terminator_lastuse() personality i32 0 { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: [[RV:%.*]] = invoke i32 @use_nocapture(ptr [[SRC]]) @@ -430,6 +456,7 @@ define void @multi_bb_memcpy(i1 %b) { ; CHECK-LABEL: define void @multi_bb_memcpy ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca i32, align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr [[SRC]]) ; CHECK-NEXT: store i32 42, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: br label [[BB0:%.*]] @@ -437,6 +464,7 @@ define void @multi_bb_memcpy(i1 %b) { ; CHECK-NEXT: br label [[BB1:%.*]] ; CHECK: bb1: ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca i32, align 4 @@ -462,11 +490,13 @@ define void @multi_bb_load_store(i1 %b) { ; CHECK-LABEL: define void @multi_bb_load_store ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca i32, align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr [[SRC]]) ; CHECK-NEXT: store i32 42, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) ; CHECK-NEXT: br label [[BB0:%.*]] ; CHECK: bb0: ; CHECK-NEXT: [[TMP2:%.*]] = call i32 @use_nocapture(ptr nocapture [[SRC]]) +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca i32, align 4 @@ -534,6 +564,7 @@ define void @multi_bb_simple_br(i1 %b) { ; CHECK-LABEL: define void @multi_bb_simple_br ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = call i32 @use_nocapture(ptr nocapture noundef [[SRC]]) ; CHECK-NEXT: br i1 [[B]], label [[BB0:%.*]], label [[BB1:%.*]] @@ -544,6 +575,7 @@ define void @multi_bb_simple_br(i1 %b) { ; CHECK-NEXT: [[TMP3:%.*]] = call i32 @use_nocapture(ptr nocapture noundef [[SRC]]) ; CHECK-NEXT: br label [[BB2]] ; CHECK: bb2: +; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 12, ptr nocapture [[SRC]]) ; CHECK-NEXT: ret void ; %src = alloca %struct.Foo, align 4 @@ -574,6 +606,7 @@ define void @multi_bb_dom_test0(i1 %b) { ; CHECK-LABEL: define void @multi_bb_dom_test0 ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: br i1 [[B]], label [[BB0:%.*]], label [[BB1:%.*]] ; CHECK: bb0: ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 @@ -657,6 +690,7 @@ define void @multi_bb_pdom_test0(i1 %b) { ; CHECK-LABEL: define void @multi_bb_pdom_test0 ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: br i1 [[B]], label [[BB0:%.*]], label [[BB1:%.*]] ; CHECK: bb0: @@ -697,6 +731,7 @@ define void @multi_bb_pdom_test1(i1 %b) { ; CHECK-LABEL: define void @multi_bb_pdom_test1 ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32 20, i32 30 }, ptr [[SRC]], align 4 ; CHECK-NEXT: br i1 [[B]], label [[BB0:%.*]], label [[BB1:%.*]] ; CHECK: bb0: @@ -735,6 +770,7 @@ define void @multi_bb_pdom_test2(i1 %b) { ; CHECK-LABEL: define void @multi_bb_pdom_test2 ; CHECK-SAME: (i1 [[B:%.*]]) { ; CHECK-NEXT: [[SRC:%.*]] = alloca [[STRUCT_FOO:%.*]], align 4 +; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 12, ptr [[SRC]]) ; CHECK-NEXT: store [[STRUCT_FOO]] { i32 10, i32... [truncated] |
| ✅ With the latest revision this PR passed the C/C++ code formatter. |
khei4 force-pushed the perf/stack-move-multi-bb-lifetime-spans branch from f4781f1 to a720474 Compare 
Contributor
| Are you planning on submitting this eventually? For use-after-scope in sanitizers the more lifetime annotations the better. |
Contributor Author
| @fmayer
Yes, I believe this patch resolves #66403. I'm also okay with you taking over this or an alternative patch if you're interested :). I'm a little busy for a few months. |
Contributor
Can you elaborate a bit what is missing? Shepherding through review, or is it not done? |
Contributor Author
Sure.
Not done yet. So, I guess the first thing to be done is to verify this is correct to some kind. This patch introduces more lifetime markers than the current main, so if it's better to be based on this patch, checking that the sanitizer won't crash for sufficient tests may be sufficient (I only checked the correctness for this patch with Thank you for pinging, if you need more concrete things about this patch, please ping me again. |
| @khei4 is there a PR here for https://reviews.llvm.org/D159075 or did that patch get lost? |
Contributor Author
Thanks! Not yet. I'm now preparing to rebase the patch, and it'll be ported with more descriptions to Github in a few weeks :) |
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
4 participants
Add this suggestion to a batch that can be applied as a single commit. This suggestion is invalid because no changes were made to the code. Suggestions cannot be applied while the pull request is closed. Suggestions cannot be applied while viewing a subset of changes. Only one suggestion per line can be applied in a batch. Add this suggestion to a batch that can be applied as a single commit. Applying suggestions on deleted lines is not supported. You must change the existing code in this line in order to create a valid suggestion. Outdated suggestions cannot be applied. This suggestion has been applied or marked resolved. Suggestions cannot be applied from pending reviews. Suggestions cannot be applied on multi-line comments. Suggestions cannot be applied while the pull request is queued to merge. Suggestion cannot be applied right now. Please check back later.
Fixes #66403
This patch did two things for the stack-move optimization reduction pattern.