1; REQUIRES: object-emission 2 3; RUN: llc -mtriple=x86_64-apple-macosx10.10.0 -o %t %s 4 5; Testcase generated from: 6; #include <stdint.h> 7; int foo(int a) { 8; int b = (int16_t)a + 8; 9; int c = (int16_t)b + 8; 10; int d = (int16_t)c + 8; 11; int e = (int16_t)d + 8; 12; int f = (int16_t)e + 8; 13; return f; 14; } 15; by emitting the IR and then manually applying mem2reg to it. 16 17; This testcase would trigger the assert commited along with it if the 18; fix of r221709 isn't applied. There is no other check except the successful 19; run of llc. 20; What happened before r221709, is that SDDbgInfo (the data structure helping 21; SelectionDAG to keep track of dbg.values) kept a map keyed by SDNode pointers. 22; This map was never purged when the SDNodes were deallocated and thus if a new 23; SDNode was allocated in the same memory, it would have an entry in the SDDbgInfo 24; map upon creation (Reallocation in the same memory can happen easily as 25; SelectionDAG uses a Recycling allocator). This behavior could turn into a 26; pathological memory consumption explosion if the DAG combiner hit the 'right' 27; allocation patterns as could be seen in PR20893. 28; By nature, this test could bitrot quite easily. If it doesn't trigger an assert 29; when run with r221709 reverted, then it really doesn't test anything anymore. 30 31; Function Attrs: nounwind ssp uwtable 32define i32 @foo(i32 %a) #0 !dbg !8 { 33entry: 34 call void @llvm.dbg.value(metadata i32 %a, i64 0, metadata !16, metadata !17), !dbg !18 35 %conv = trunc i32 %a to i16, !dbg !19 36 %conv1 = sext i16 %conv to i32, !dbg !19 37 %add = add nsw i32 %conv1, 8, !dbg !19 38 call void @llvm.dbg.value(metadata i32 %add, i64 0, metadata !20, metadata !17), !dbg !21 39 %conv2 = trunc i32 %add to i16, !dbg !22 40 %conv3 = sext i16 %conv2 to i32, !dbg !22 41 %add4 = add nsw i32 %conv3, 8, !dbg !22 42 call void @llvm.dbg.value(metadata i32 %add4, i64 0, metadata !23, metadata !17), !dbg !24 43 %conv5 = trunc i32 %add4 to i16, !dbg !25 44 %conv6 = sext i16 %conv5 to i32, !dbg !25 45 %add7 = add nsw i32 %conv6, 8, !dbg !25 46 call void @llvm.dbg.value(metadata i32 %add7, i64 0, metadata !26, metadata !17), !dbg !27 47 %conv8 = trunc i32 %add7 to i16, !dbg !28 48 %conv9 = sext i16 %conv8 to i32, !dbg !28 49 %add10 = add nsw i32 %conv9, 8, !dbg !28 50 call void @llvm.dbg.value(metadata i32 %add10, i64 0, metadata !29, metadata !17), !dbg !30 51 %conv11 = trunc i32 %add10 to i16, !dbg !31 52 %conv12 = sext i16 %conv11 to i32, !dbg !31 53 %add13 = add nsw i32 %conv12, 8, !dbg !31 54 call void @llvm.dbg.value(metadata i32 %add13, i64 0, metadata !32, metadata !17), !dbg !33 55 ret i32 %add13, !dbg !34 56} 57 58; Function Attrs: nounwind readnone 59declare void @llvm.dbg.declare(metadata, metadata, metadata) #1 60 61; Function Attrs: nounwind readnone 62declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1 63 64attributes #0 = { nounwind ssp uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } 65attributes #1 = { nounwind readnone } 66 67!llvm.dbg.cu = !{!0} 68!llvm.module.flags = !{!13, !14} 69!llvm.ident = !{!15} 70 71!0 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 3.6.0 ", isOptimized: false, emissionKind: 1, file: !1, enums: !2, retainedTypes: !3, subprograms: !7, globals: !2, imports: !2) 72!1 = !DIFile(filename: "ghost-sdnode-dbgvalues.c", directory: "/tmp") 73!2 = !{} 74!3 = !{!4} 75!4 = !DIDerivedType(tag: DW_TAG_typedef, name: "int16_t", line: 30, file: !5, baseType: !6) 76!5 = !DIFile(filename: "/usr/include/sys/_types/_int16_t.h", directory: "/tmp") 77!6 = !DIBasicType(tag: DW_TAG_base_type, name: "short", size: 16, align: 16, encoding: DW_ATE_signed) 78!7 = !{!8} 79!8 = distinct !DISubprogram(name: "foo", line: 3, isLocal: false, isDefinition: true, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 3, file: !1, scope: !9, type: !10, variables: !2) 80!9 = !DIFile(filename: "ghost-sdnode-dbgvalues.c", directory: "/tmp") 81!10 = !DISubroutineType(types: !11) 82!11 = !{!12, !12} 83!12 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed) 84!13 = !{i32 2, !"Dwarf Version", i32 2} 85!14 = !{i32 2, !"Debug Info Version", i32 3} 86!15 = !{!"clang version 3.6.0 "} 87!16 = !DILocalVariable(name: "a", line: 3, arg: 1, scope: !8, file: !9, type: !12) 88!17 = !DIExpression() 89!18 = !DILocation(line: 3, column: 13, scope: !8) 90!19 = !DILocation(line: 4, column: 5, scope: !8) 91!20 = !DILocalVariable(name: "b", line: 4, scope: !8, file: !9, type: !12) 92!21 = !DILocation(line: 4, column: 9, scope: !8) 93!22 = !DILocation(line: 5, column: 5, scope: !8) 94!23 = !DILocalVariable(name: "c", line: 5, scope: !8, file: !9, type: !12) 95!24 = !DILocation(line: 5, column: 9, scope: !8) 96!25 = !DILocation(line: 6, column: 5, scope: !8) 97!26 = !DILocalVariable(name: "d", line: 6, scope: !8, file: !9, type: !12) 98!27 = !DILocation(line: 6, column: 9, scope: !8) 99!28 = !DILocation(line: 7, column: 5, scope: !8) 100!29 = !DILocalVariable(name: "e", line: 7, scope: !8, file: !9, type: !12) 101!30 = !DILocation(line: 7, column: 9, scope: !8) 102!31 = !DILocation(line: 8, column: 5, scope: !8) 103!32 = !DILocalVariable(name: "f", line: 8, scope: !8, file: !9, type: !12) 104!33 = !DILocation(line: 8, column: 9, scope: !8) 105!34 = !DILocation(line: 9, column: 5, scope: !8) 106