Commit 1984a27d authored by Tom Weaver's avatar Tom Weaver
Browse files

[DBG][OPT] Attempt to salvage or undef debug info when removing trivially... 

[DBG][OPT] Attempt to salvage or undef debug info when removing trivially deletable instructions in the Reassociate Expression pass.

Reviewed By: aprantl, vsk

Differential revision: https://reviews.llvm.org/D69943
parent 75af15d8

llvm/lib/Transforms/Scalar/Reassociate.cpp.rej

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File added.

Preview size limit exceeded, changes collapsed.

llvm/test/Transforms/Reassociate/reassociate_salvages_debug_info.ll

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; RUN: opt < %s -reassociate -S | FileCheck %s



; Check that reassociate pass now salvages debug info when dropping instructions.



define hidden i32 @main(i32 %argc, i8** %argv) {

entry:

  ; CHECK: call void @llvm.dbg.value(metadata i32 %argc, metadata [[VAR_B:![0-9]+]], metadata !DIExpression(DW_OP_plus_uconst, 1, DW_OP_stack_value))

  %add = add nsw i32 %argc, 1, !dbg !26

  call void @llvm.dbg.value(metadata i32 %add, metadata !22, metadata !DIExpression()), !dbg !25

  %add1 = add nsw i32 %argc, %add, !dbg !27

  ret i32 %add1, !dbg !28

}



declare void @llvm.dbg.declare(metadata, metadata, metadata) #1

declare void @llvm.dbg.value(metadata, metadata, metadata) #1



!llvm.dbg.cu = !{!0}

!llvm.module.flags = !{!3, !4, !5, !6}

!llvm.ident = !{!7}



!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 10.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, debugInfoForProfiling: true, nameTableKind: None)

!1 = !DIFile(filename: "test2.cpp", directory: "C:\")

!2 = !{}

!3 = !{i32 2, !"Dwarf Version", i32 4}

!4 = !{i32 2, !"Debug Info Version", i32 3}

!5 = !{i32 1, !"wchar_size", i32 2}

!6 = !{i32 7, !"PIC Level", i32 2}

!7 = !{!"clang version 10.0.0"}

!8 = distinct !DISubprogram(name: "main", scope: !9, file: !9, line: 1, type: !10, scopeLine: 1, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !18)

!9 = !DIFile(filename: "./test2.cpp", directory: "C:\")

!10 = !DISubroutineType(types: !11)

!11 = !{!12, !13, !14}

!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)

!13 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !12)

!14 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !15, size: 64)

!15 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !16, size: 64)

!16 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !17)

!17 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)

!18 = !{!19, !20, !21, !22, !23, !24}

!19 = !DILocalVariable(name: "argc", arg: 1, scope: !8, file: !9, line: 1, type: !13)

!20 = !DILocalVariable(name: "argv", arg: 2, scope: !8, file: !9, line: 1, type: !14)

!21 = !DILocalVariable(name: "a", scope: !8, file: !9, line: 2, type: !12)

; CHECK: [[VAR_B]] = !DILocalVariable(name: "b"

!22 = !DILocalVariable(name: "b", scope: !8, file: !9, line: 3, type: !12)

!23 = !DILocalVariable(name: "to_return", scope: !8, file: !9, line: 4, type: !12)

!24 = !DILocalVariable(name: "result", scope: !8, file: !9, line: 5, type: !12)

!25 = !DILocation(line: 0, scope: !8)

!26 = !DILocation(line: 3, scope: !8)

!27 = !DILocation(line: 4, scope: !8)

!28 = !DILocation(line: 6, scope: !8)

llvm/test/Transforms/Reassociate/undef_intrinsics_when_deleting_instructions.ll

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; RUN: opt < %s -reassociate -S | FileCheck %s



; Check that reassociate pass now undefs debug intrinsics that reference a value

; that gets dropped and cannot be salvaged.



define hidden i32 @main() local_unnamed_addr {

entry:

  %foo = alloca i32, align 4, !dbg !20

  %foo.0.foo.0..sroa_cast = bitcast i32* %foo to i8*, !dbg !20

  call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %foo.0.foo.0..sroa_cast), !dbg !20

  store volatile i32 4, i32* %foo, align 4, !dbg !20, !tbaa !21

  %foo.0.foo.0. = load volatile i32, i32* %foo, align 4, !dbg !25, !tbaa !21

  %foo.0.foo.0.15 = load volatile i32, i32* %foo, align 4, !dbg !27, !tbaa !21

  %foo.0.foo.0.16 = load volatile i32, i32* %foo, align 4, !dbg !28, !tbaa !21

  ; CHECK-NOT: %add = add nsw i32 %foo.0.foo.0., %foo.0.foo.0.15

  %add = add nsw i32 %foo.0.foo.0., %foo.0.foo.0.15, !dbg !29

  ; CHECK: call void @llvm.dbg.value(metadata i32 undef, metadata [[VAR_A:![0-9]+]], metadata !DIExpression())

  call void @llvm.dbg.value(metadata i32 %add, metadata !19, metadata !DIExpression()), !dbg !26

  %foo.0.foo.0.17 = load volatile i32, i32* %foo, align 4, !dbg !30, !tbaa !21

  %cmp = icmp eq i32 %foo.0.foo.0.17, 4, !dbg !30

  br i1 %cmp, label %if.then, label %if.end, !dbg !32



  ; CHECK-LABEL: if.then:

if.then:

  ; CHECK-NOT: %add1 = add nsw i32 %add, %foo.0.foo.0.16

  %add1 = add nsw i32 %add, %foo.0.foo.0.16, !dbg !33

  ; CHECK: call void @llvm.dbg.value(metadata i32 undef, metadata [[VAR_A]], metadata !DIExpression())

  call void @llvm.dbg.value(metadata i32 %add1, metadata !19, metadata !DIExpression()), !dbg !26

  ; CHECK: call void @llvm.dbg.value(metadata i32 undef, metadata [[VAR_CHEESE:![0-9]+]], metadata !DIExpression())

  call void @llvm.dbg.value(metadata i32 %add, metadata !18, metadata !DIExpression()), !dbg !26

  %sub = add nsw i32 %add, -12, !dbg !34

  %sub3 = sub nsw i32 %add1, %sub, !dbg !34

  %mul = mul nsw i32 %sub3, 20, !dbg !36

  %div = sdiv i32 %mul, 3, !dbg !37

  br label %if.end, !dbg !38



if.end:

  %a.0 = phi i32 [ %div, %if.then ], [ 0, %entry ], !dbg !39

  call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull %foo.0.foo.0..sroa_cast), !dbg !40

  ret i32 %a.0, !dbg !41

}



declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture) #1

declare void @llvm.dbg.declare(metadata, metadata, metadata) #2

declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture) #1

declare void @llvm.dbg.value(metadata, metadata, metadata) #2



!llvm.dbg.cu = !{!0}

!llvm.module.flags = !{!3, !4, !5, !6}

!llvm.ident = !{!7}



!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, debugInfoForProfiling: true, nameTableKind: None)

!1 = !DIFile(filename: "test.cpp", directory: "F:\")

!2 = !{}

!3 = !{i32 2, !"Dwarf Version", i32 4}

!4 = !{i32 2, !"Debug Info Version", i32 3}

!5 = !{i32 1, !"wchar_size", i32 2}

!6 = !{i32 7, !"PIC Level", i32 2}

!7 = !{!"clang version 10.0.0"}

!8 = distinct !DISubprogram(name: "main", scope: !9, file: !9, line: 1, type: !10, scopeLine: 1, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !13)

!9 = !DIFile(filename: "./test.cpp", directory: "F:\")

!10 = !DISubroutineType(types: !11)

!11 = !{!12}

!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)

!13 = !{!14, !16, !17, !18, !19}

!14 = !DILocalVariable(name: "foo", scope: !8, file: !9, line: 2, type: !15)

!15 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !12)

!16 = !DILocalVariable(name: "read1", scope: !8, file: !9, line: 3, type: !12)

!17 = !DILocalVariable(name: "read2", scope: !8, file: !9, line: 4, type: !12)

; CHECK: [[VAR_CHEESE]] = !DILocalVariable(name: "cheese"

!18 = !DILocalVariable(name: "cheese", scope: !8, file: !9, line: 6, type: !12)

; CHECK: [[VAR_A]] = !DILocalVariable(name: "a"

!19 = !DILocalVariable(name: "a", scope: !8, file: !9, line: 7, type: !12)

!20 = !DILocation(line: 2, scope: !8)

!21 = !{!22, !22, i64 0}

!22 = !{!"int", !23, i64 0}

!23 = !{!"omnipotent char", !24, i64 0}

!24 = !{!"Simple C++ TBAA"}

!25 = !DILocation(line: 3, scope: !8)

!26 = !DILocation(line: 0, scope: !8)

!27 = !DILocation(line: 4, scope: !8)

!28 = !DILocation(line: 6, scope: !8)

!29 = !DILocation(line: 7, scope: !8)

!30 = !DILocation(line: 10, scope: !31)

!31 = distinct !DILexicalBlock(scope: !8, file: !9, line: 10)

!32 = !DILocation(line: 10, scope: !8)

!33 = !DILocation(line: 8, scope: !8)

!34 = !DILocation(line: 12, scope: !35)

!35 = distinct !DILexicalBlock(scope: !31, file: !9, line: 10)

!36 = !DILocation(line: 13, scope: !35)

!37 = !DILocation(line: 14, scope: !35)

!38 = !DILocation(line: 15, scope: !35)

!39 = !DILocation(line: 0, scope: !31)

!40 = !DILocation(line: 20, scope: !8)

!41 = !DILocation(line: 19, scope: !8)