Index: llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp =================================================================== --- llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -6151,6 +6151,10 @@ const auto *Rec = cast(CachedDVI.SCEV); if (!Rec->isAffine()) return; + + // Some SCEVs are very large and require excessive resources to translate. + if(CachedDVI.SCEV->getExpressionSize() > 64) + return; // Initialise a new builder with the iteration count expression. In // combination with the value's SCEV this enables recovery. @@ -6196,7 +6200,11 @@ if (!IVAddRec->isAffine()) return; - // The iteratioun count is required to recover location values. + // Some SCEVs are very large and require excessive resources to translate. + if(IVAddRec->getExpressionSize() > 64) + return; + + // The iteration count is required to recover location values. SCEVDbgValueBuilder IterCountExpr; IterCountExpr.pushValue(LSRInductionVar); if (!IterCountExpr.SCEVToIterCountExpr(*IVAddRec, SE)) Index: llvm/test/Transforms/LoopStrengthReduce/pr51656.ll =================================================================== --- /dev/null +++ llvm/test/Transforms/LoopStrengthReduce/pr51656.ll @@ -0,0 +1,142 @@ +; RUN: opt -loop-reduce -S %s | FileCheck %s +; REQUIRES: x86-registered-target + +;; This test ensures that no attempt is made to translate long SCEVs into +;; DIExpressions. Attempting the translation can use excessive resources and +;; result in crashes. + +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@c = dso_local local_unnamed_addr global i32 0, align 4, !dbg !0 +@b = dso_local local_unnamed_addr global i32 0, align 4, !dbg !9 +@a = dso_local local_unnamed_addr global i32 0, align 4, !dbg !5 + +define dso_local i32 @d() local_unnamed_addr #0 !dbg !16 { +entry: + %b.promoted = load i32, i32* @b, align 4, !tbaa !29 + %mul = mul nsw i32 %b.promoted, %b.promoted, !dbg !33 + %mul.1 = mul nsw i32 %mul, %mul, !dbg !33 + %mul.2 = mul nsw i32 %mul.1, %mul.1, !dbg !33 + %mul.3 = mul nsw i32 %mul.2, %mul.2, !dbg !33 + %mul.4 = mul nsw i32 %mul.3, %mul.3, !dbg !33 + %mul.5 = mul nsw i32 %mul.4, %mul.4, !dbg !33 + %mul.6 = mul nsw i32 %mul.5, %mul.5, !dbg !33 + %mul.7 = mul nsw i32 %mul.6, %mul.6, !dbg !33 + %mul.8 = mul nsw i32 %mul.7, %mul.7, !dbg !33 + %mul.9 = mul nsw i32 %mul.8, %mul.8, !dbg !33 + %mul.10 = mul nsw i32 %mul.9, %mul.9, !dbg !33 + %mul.11 = mul nsw i32 %mul.10, %mul.10, !dbg !33 + %mul.12 = mul nsw i32 %mul.11, %mul.11, !dbg !33 + %mul.13 = mul nsw i32 %mul.12, %mul.12, !dbg !33 + %mul.14 = mul nsw i32 %mul.13, %mul.13, !dbg !33 + %mul.15 = mul nsw i32 %mul.14, %mul.14, !dbg !33 + %mul.16 = mul nsw i32 %mul.15, %mul.15, !dbg !33 + %mul.17 = mul nsw i32 %mul.16, %mul.16, !dbg !33 + %mul.18 = mul nsw i32 %mul.17, %mul.17, !dbg !33 + %mul.19 = mul nsw i32 %mul.18, %mul.18, !dbg !33 + %mul.20 = mul nsw i32 %mul.19, %mul.19, !dbg !33 + %mul.21 = mul nsw i32 %mul.20, %mul.20, !dbg !33 + %mul.22 = mul nsw i32 %mul.21, %mul.21, !dbg !33 + %mul.23 = mul nsw i32 %mul.22, %mul.22, !dbg !33 + %mul.24 = mul nsw i32 %mul.23, %mul.23, !dbg !33 + %mul.25 = mul nsw i32 %mul.24, %mul.24, !dbg !33 + %mul.26 = mul nsw i32 %mul.25, %mul.25, !dbg !33 + %mul.27 = mul nsw i32 %mul.26, %mul.26, !dbg !33 + %mul.28 = mul nsw i32 %mul.27, %mul.27, !dbg !33 + %mul.29 = mul nsw i32 %mul.28, %mul.28, !dbg !33 + %mul.30 = mul nsw i32 %mul.29, %mul.29, !dbg !33 + %mul.31 = mul nsw i32 %mul.30, %mul.30, !dbg !33 + %mul.32 = mul nsw i32 %mul.31, %mul.31, !dbg !33 + %mul.33 = mul nsw i32 %mul.32, %mul.32, !dbg !33 + %mul.34 = mul nsw i32 %mul.33, %mul.33, !dbg !33 + %mul.35 = mul nsw i32 %mul.34, %mul.34, !dbg !33 + %mul.36 = mul nsw i32 %mul.35, %mul.35, !dbg !33 + %mul.37 = mul nsw i32 %mul.36, %mul.36, !dbg !33 + %mul.38 = mul nsw i32 %mul.37, %mul.37, !dbg !33 + %mul.39 = mul nsw i32 %mul.38, %mul.38, !dbg !33 + %mul.40 = mul nsw i32 %mul.39, %mul.39, !dbg !33 + %mul.41 = mul nsw i32 %mul.40, %mul.40, !dbg !33 + %mul.42 = mul nsw i32 %mul.41, %mul.41, !dbg !33 + %mul.43 = mul nsw i32 %mul.42, %mul.42, !dbg !33 + %mul.44 = mul nsw i32 %mul.43, %mul.43, !dbg !33 + %mul.45 = mul nsw i32 %mul.44, %mul.44, !dbg !33 + %mul.46 = mul nsw i32 %mul.45, %mul.45, !dbg !33 + %mul.47 = mul nsw i32 %mul.46, %mul.46, !dbg !33 + store i32 49, i32* @c, align 4, !dbg !36, !tbaa !29 + store i32 %mul.47, i32* @b, align 4, !dbg !37, !tbaa !29 + %.pr = load i32, i32* @a, align 4, !dbg !38, !tbaa !29 + %tobool.not8 = icmp eq i32 %.pr, 0, !dbg !39 + br i1 %tobool.not8, label %for.end3, label %for.body2.preheader, !dbg !39 + +for.body2.preheader: ; preds = %entry + br label %for.body2, !dbg !39 + +for.body2: ; preds = %for.body2.preheader, %for.body2 + %0 = phi i32 [ %sub, %for.body2 ], [ %.pr, %for.body2.preheader ] + %sub = sub nsw i32 %0, %mul.47, !dbg !40 + ;; CHECK: call void @llvm.dbg.value(metadata !DIArgList(i32 undef, i32 %mul.47), metadata !20, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_minus, DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_LLVM_convert, 64, DW_ATE_signed, DW_OP_stack_value)) + call void @llvm.dbg.value(metadata i32 %sub, metadata !20, metadata !DIExpression(DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_LLVM_convert, 64, DW_ATE_signed, DW_OP_stack_value)), !dbg !41 + %tobool.not = icmp eq i32 %sub, 0, !dbg !39 + br i1 %tobool.not, label %for.cond1.for.end3_crit_edge, label %for.body2, !dbg !39, !llvm.loop !42 + +for.cond1.for.end3_crit_edge: ; preds = %for.body2 + store i32 0, i32* @a, align 4, !dbg !40, !tbaa !29 + br label %for.end3, !dbg !39 + +for.end3: ; preds = %for.cond1.for.end3_crit_edge, %entry + ret i32 undef, !dbg !45 +} + +declare void @llvm.dbg.value(metadata, metadata, metadata) #1 + +!llvm.dbg.cu = !{!2} +!llvm.module.flags = !{!11, !12, !13, !14} +!llvm.ident = !{!15} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "c", scope: !2, file: !7, line: 2, type: !8, isLocal: false, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 14.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, globals: !4, splitDebugInlining: false, nameTableKind: None) +!3 = !DIFile(filename: "test.c", directory: "/test") +!4 = !{!5, !9, !0} +!5 = !DIGlobalVariableExpression(var: !6, expr: !DIExpression()) +!6 = distinct !DIGlobalVariable(name: "a", scope: !2, file: !7, line: 2, type: !8, isLocal: false, isDefinition: true) +!7 = !DIFile(filename: "./test.c", directory: "/test") +!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!9 = !DIGlobalVariableExpression(var: !10, expr: !DIExpression()) +!10 = distinct !DIGlobalVariable(name: "b", scope: !2, file: !7, line: 2, type: !8, isLocal: false, isDefinition: true) +!11 = !{i32 7, !"Dwarf Version", i32 4} +!12 = !{i32 2, !"Debug Info Version", i32 3} +!13 = !{i32 1, !"wchar_size", i32 4} +!14 = !{i32 7, !"uwtable", i32 1} +!15 = !{!"clang version 14.0.0"} +!16 = distinct !DISubprogram(name: "d", scope: !7, file: !7, line: 3, type: !17, scopeLine: 3, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !19) +!17 = !DISubroutineType(types: !18) +!18 = !{!8} +!19 = !{!20} +!20 = !DILocalVariable(name: "e", scope: !21, file: !7, line: 8, type: !24) +!21 = distinct !DILexicalBlock(scope: !22, file: !7, line: 7, column: 14) +!22 = distinct !DILexicalBlock(scope: !23, file: !7, line: 7, column: 3) +!23 = distinct !DILexicalBlock(scope: !16, file: !7, line: 7, column: 3) +!24 = !DIDerivedType(tag: DW_TAG_typedef, name: "uint64_t", file: !25, line: 27, baseType: !26) +!25 = !DIFile(filename: "/usr/include/x86_64-linux-gnu/bits/stdint-uintn.h", directory: "") +!26 = !DIDerivedType(tag: DW_TAG_typedef, name: "__uint64_t", file: !27, line: 44, baseType: !28) +!27 = !DIFile(filename: "/usr/include/x86_64-linux-gnu/bits/types.h", directory: "") +!28 = !DIBasicType(name: "long unsigned int", size: 64, encoding: DW_ATE_unsigned) +!29 = !{!30, !30, i64 0} +!30 = !{!"int", !31, i64 0} +!31 = !{!"omnipotent char", !32, i64 0} +!32 = !{!"Simple C/C++ TBAA"} +!33 = !DILocation(line: 6, column: 7, scope: !34) +!34 = distinct !DILexicalBlock(scope: !35, file: !7, line: 5, column: 3) +!35 = distinct !DILexicalBlock(scope: !16, file: !7, line: 5, column: 3) +!36 = !DILocation(line: 0, scope: !16) +!37 = !DILocation(line: 0, scope: !34) +!38 = !DILocation(line: 7, column: 10, scope: !22) +!39 = !DILocation(line: 7, column: 3, scope: !23) +!40 = !DILocation(line: 8, column: 20, scope: !21) +!41 = !DILocation(line: 0, scope: !21) +!42 = distinct !{!42, !39, !43, !44} +!43 = !DILocation(line: 9, column: 3, scope: !23) +!44 = !{!"llvm.loop.mustprogress"} +!45 = !DILocation(line: 10, column: 1, scope: !16)