From 32e6e8415c2ce1dbaea4c754d65ccd53e43a4ec9 Mon Sep 17 00:00:00 2001 From: Alexey Bataev Date: Tue, 1 Oct 2019 16:19:10 +0000 Subject: [PATCH] [OPENMP]Fix PR43516: Compiler crash with collapse(2) on non-rectangular loop. Missed check if the condition is also dependent when building final expressions for the collapsed loop directives. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@373348 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Sema/SemaOpenMP.cpp | 18 +++++++++++++----- test/OpenMP/for_codegen.cpp | 33 ++++++++++++++++----------------- 2 files changed, 29 insertions(+), 22 deletions(-) diff --git a/lib/Sema/SemaOpenMP.cpp b/lib/Sema/SemaOpenMP.cpp index b3a2ed62a7..42e1755b58 100644 --- a/lib/Sema/SemaOpenMP.cpp +++ b/lib/Sema/SemaOpenMP.cpp @@ -6247,13 +6247,21 @@ Expr *OpenMPIterationSpaceChecker::buildFinalCondition(Scope *S) const { Expr *OpenMPIterationSpaceChecker::buildPreCond( Scope *S, Expr *Cond, llvm::MapVector &Captures) const { + // Do not build a precondition when the condition/initialization is dependent + // to prevent pessimistic early loop exit. + // TODO: this can be improved by calculating min/max values but not sure that + // it will be very effective. + if (CondDependOnLC || InitDependOnLC) + return SemaRef.PerformImplicitConversion( + SemaRef.ActOnIntegerConstant(SourceLocation(), 1).get(), + SemaRef.Context.BoolTy, /*Action=*/Sema::AA_Casting, + /*AllowExplicit=*/true).get(); + // Try to build LB UB, where is <, >, <=, or >=. Sema::TentativeAnalysisScope Trap(SemaRef); - ExprResult NewLB = - InitDependOnLC ? LB : tryBuildCapture(SemaRef, LB, Captures); - ExprResult NewUB = - CondDependOnLC ? UB : tryBuildCapture(SemaRef, UB, Captures); + ExprResult NewLB = tryBuildCapture(SemaRef, LB, Captures); + ExprResult NewUB = tryBuildCapture(SemaRef, UB, Captures); if (!NewLB.isUsable() || !NewUB.isUsable()) return nullptr; @@ -7425,7 +7433,7 @@ checkOpenMPLoop(OpenMPDirectiveKind DKind, Expr *CollapseLoopCountExpr, Built.DependentCounters[Cnt] = nullptr; Built.DependentInits[Cnt] = nullptr; Built.FinalsConditions[Cnt] = nullptr; - if (IS.IsNonRectangularLB) { + if (IS.IsNonRectangularLB || IS.IsNonRectangularUB) { Built.DependentCounters[Cnt] = Built.Counters[NestedLoopCount - 1 - IS.LoopDependentIdx]; Built.DependentInits[Cnt] = diff --git a/test/OpenMP/for_codegen.cpp b/test/OpenMP/for_codegen.cpp index 756d6ccebf..925235ef96 100644 --- a/test/OpenMP/for_codegen.cpp +++ b/test/OpenMP/for_codegen.cpp @@ -89,23 +89,6 @@ void loop_with_counter_collapse() { // CHECK: [[NUM_ITERS_VAL:%.+]] = sub nsw i64 [[MUL]], 1 // CHECK: store i64 [[NUM_ITERS_VAL]], i64* [[NUM_ITERS:%.+]], - // Initialization - // CHECK: store i32 0, i32* [[I:%.+]], - // CHECK: [[I_INIT:%.+]] = load i32, i32* [[I]], - // CHECK: store i32 [[I_INIT]], i32* [[J:%.+]], - - // LIFETIME: call void @llvm.lifetime.end - // LIFETIME: call void @llvm.lifetime.end - - // Precondition for j counter - // CHECK: store i32 0, i32* [[TMP_I:%.+]], - // CHECK: [[J_LB_VAL:%.+]] = load i32, i32* [[TMP_I]], - // CHECK: [[I_VAL:%.+]] = load i32, i32* [[TMP_I]], - // CHECK: [[J_UB_VAL:%.+]] = add nsw i32 4, [[I_VAL]] - // CHECK: [[CMP:%.+]] = icmp slt i32 [[J_LB_VAL]], [[J_UB_VAL]] - // CHECK: br i1 [[CMP]], label %[[THEN:[^,]+]], label %[[ELSE:[^,]+]] - - // CHECK: [[THEN]]: // CHECK: store i64 0, i64* [[LB:%.+]], // CHECK: [[NUM_ITERS_VAL:%.+]] = load i64, i64* [[NUM_ITERS]], // CHECK: store i64 [[NUM_ITERS_VAL]], i64* [[UB:%.+]], @@ -633,6 +616,22 @@ void for_with_references() { k = cnt; } +// CHECK-LABEL: for_with_references_dep_cond +void for_with_references_dep_cond() { +// CHECK: [[I:%.+]] = alloca i8, +// CHECK: [[CNT:%.+]] = alloca i8*, +// CHECK: [[CNT_PRIV:%.+]] = alloca i8, +// CHECK: call void @__kmpc_for_static_init_8( +// CHECK-NOT: load i8, i8* [[CNT]], +// CHECK: call void @__kmpc_for_static_fini( + char i = 0; + char &cnt = i; +#pragma omp for collapse(2) + for (cnt = 0; cnt < 2; ++cnt) + for (int j = 0; j < 4 + cnt; j++) + k = cnt; +} + struct Bool { Bool(bool b) : b(b) {} operator bool() const { return b; } -- 2.40.0