[llvm] r251680 - Update the discriminator assignment algorithm
David Blaikie via llvm-commits
llvm-commits at lists.llvm.org
Thu Oct 29 21:13:54 PDT 2015
On Thu, Oct 29, 2015 at 7:38 PM, Dehao Chen via llvm-commits <
llvm-commits at lists.llvm.org> wrote:
> Author: dehao
> Date: Thu Oct 29 21:38:29 2015
> New Revision: 251680
>
> URL: http://llvm.org/viewvc/llvm-project?rev=251680&view=rev
> Log:
> Update the discriminator assignment algorithm
>
> * If a scope has already been assigned a discriminator, do not reassign a
> nested discriminator for it.
> * If the file and line both match, even if the column does not match, we
> should assign a new discriminator for the stmt.
>
Why do we need a discriminator even when the column is distinct?
>
> original code:
> ; #1 int foo(int i) {
> ; #2 if (i == 3 || i == 5) return 100; else return 99;
> ; #3 }
>
> ; i == 3: discriminator 0
> ; i == 5: discriminator 2
> ; return 100: discriminator 1
> ; return 99: discriminator 3
>
> Added:
> llvm/trunk/test/Transforms/AddDiscriminators/oneline.ll
> Modified:
> llvm/trunk/lib/Transforms/Utils/AddDiscriminators.cpp
>
> Modified: llvm/trunk/lib/Transforms/Utils/AddDiscriminators.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/AddDiscriminators.cpp?rev=251680&r1=251679&r2=251680&view=diff
>
> ==============================================================================
> --- llvm/trunk/lib/Transforms/Utils/AddDiscriminators.cpp (original)
> +++ llvm/trunk/lib/Transforms/Utils/AddDiscriminators.cpp Thu Oct 29
> 21:38:29 2015
> @@ -180,7 +180,7 @@ bool AddDiscriminators::runOnFunction(Fu
> BasicBlock *Succ = Last->getSuccessor(I);
> Instruction *First = Succ->getFirstNonPHIOrDbgOrLifetime();
> const DILocation *FirstDIL = First->getDebugLoc();
> - if (!FirstDIL)
> + if (!FirstDIL || FirstDIL->getDiscriminator())
> continue;
>
> // If the first instruction (First) of Succ is at the same file
> @@ -202,21 +202,22 @@ bool AddDiscriminators::runOnFunction(Fu
> unsigned Discriminator = FirstDIL->computeNewDiscriminator();
> auto *NewScope =
> Builder.createLexicalBlockFile(Scope, File, Discriminator);
> - auto *NewDIL =
> - DILocation::get(Ctx, FirstDIL->getLine(),
> FirstDIL->getColumn(),
> - NewScope, FirstDIL->getInlinedAt());
> - DebugLoc newDebugLoc = NewDIL;
>
> // Attach this new debug location to First and every
> // instruction following First that shares the same location.
> for (BasicBlock::iterator I1(*First), E1 = Succ->end(); I1 != E1;
> ++I1) {
> - if (I1->getDebugLoc().get() != FirstDIL)
> - break;
> - I1->setDebugLoc(newDebugLoc);
> - DEBUG(dbgs() << NewDIL->getFilename() << ":" <<
> NewDIL->getLine()
> - << ":" << NewDIL->getColumn() << ":"
> - << NewDIL->getDiscriminator() << *I1 << "\n");
> + const DILocation *CurrentDIL = I1->getDebugLoc();
> + if (CurrentDIL && CurrentDIL->getLine() == FirstDIL->getLine()
> &&
> + CurrentDIL->getFilename() == FirstDIL->getFilename()) {
> + I1->setDebugLoc(DILocation::get(Ctx, CurrentDIL->getLine(),
> + CurrentDIL->getColumn(),
> NewScope,
> + CurrentDIL->getInlinedAt()));
> + DEBUG(dbgs() << CurrentDIL->getFilename() << ":"
> + << CurrentDIL->getLine() << ":"
> + << CurrentDIL->getColumn() << ":"
> + << CurrentDIL->getDiscriminator() << *I1 <<
> "\n");
> + }
> }
> DEBUG(dbgs() << "\n");
> Changed = true;
>
> Added: llvm/trunk/test/Transforms/AddDiscriminators/oneline.ll
> URL:
> http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/AddDiscriminators/oneline.ll?rev=251680&view=auto
>
> ==============================================================================
> --- llvm/trunk/test/Transforms/AddDiscriminators/oneline.ll (added)
> +++ llvm/trunk/test/Transforms/AddDiscriminators/oneline.ll Thu Oct 29
> 21:38:29 2015
> @@ -0,0 +1,98 @@
> +; RUN: opt < %s -add-discriminators -S | FileCheck %s
> +
> +; Discriminator support for code that is written in one line:
> +; #1 int foo(int i) {
> +; #2 if (i == 3 || i == 5) return 100; else return 99;
> +; #3 }
> +
> +; i == 3: discriminator 0
> +; i == 5: discriminator 2
> +; return 100: discriminator 1
> +; return 99: discriminator 3
> +
> +define i32 @_Z3fooi(i32 %i) #0 {
> + %1 = alloca i32, align 4
> + %2 = alloca i32, align 4
> + store i32 %i, i32* %2, align 4, !tbaa !13
> + call void @llvm.dbg.declare(metadata i32* %2, metadata !9, metadata
> !17), !dbg !18
> + %3 = load i32, i32* %2, align 4, !dbg !19, !tbaa !13
> + %4 = icmp eq i32 %3, 3, !dbg !21
> + br i1 %4, label %8, label %5, !dbg !22
> +
> +; <label>:5 ; preds = %0
> + %6 = load i32, i32* %2, align 4, !dbg !23, !tbaa !13
> +; CHECK: %6 = load i32, i32* %2, align 4, !dbg ![[THEN1:[0-9]+]],{{.*}}
> +
> + %7 = icmp eq i32 %6, 5, !dbg !24
> +; CHECK: %7 = icmp eq i32 %6, 5, !dbg ![[THEN2:[0-9]+]]
> +
> + br i1 %7, label %8, label %9, !dbg !25
> +; CHECK: br i1 %7, label %8, label %9, !dbg ![[THEN3:[0-9]+]]
> +
> +; <label>:8 ; preds = %5, %0
> + store i32 100, i32* %1, align 4, !dbg !26
> +; CHECK: store i32 100, i32* %1, align 4, !dbg ![[ELSE:[0-9]+]]
> +
> + br label %10, !dbg !26
> +; CHECK: br label %10, !dbg ![[ELSE]]
> +
> +; <label>:9 ; preds = %5
> + store i32 99, i32* %1, align 4, !dbg !27
> +; CHECK: store i32 99, i32* %1, align 4, !dbg ![[COMBINE:[0-9]+]]
> +
> + br label %10, !dbg !27
> +; CHECK: br label %10, !dbg ![[COMBINE]]
> +
> +; <label>:10 ; preds = %9, %8
> + %11 = load i32, i32* %1, align 4, !dbg !28
> + ret i32 %11, !dbg !28
> +}
> +
> +; Function Attrs: nounwind readnone
> +declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
> +
> +attributes #0 = { nounwind uwtable "disable-tail-calls"="false"
> "less-precise-fpmad"="false" "no-frame-pointer-elim"="false"
> "no-infs-fp-math"="false" "no-nans-fp-math"="false"
> "stack-protector-buffer-size"="8" "target-cpu"="x86-64"
> "target-features"="+fxsr,+mmx,+sse,+sse2" "unsafe-fp-math"="false"
> "use-soft-float"="false" }
> +attributes #1 = { nounwind readnone }
> +
> +!llvm.dbg.cu = !{!0}
> +!llvm.module.flags = !{!10, !11}
> +!llvm.ident = !{!12}
> +
> +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1,
> producer: "clang version 3.8.0 (trunk 250915)", isOptimized: true,
> runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3)
> +!1 = !DIFile(filename: "a.cc", directory:
> "/usr/local/google/home/dehao/discr")
> +!2 = !{}
> +!3 = !{!4}
> +!4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope:
> !1, file: !1, line: 1, type: !5, isLocal: false, isDefinition: true,
> scopeLine: 1, flags: DIFlagPrototyped, isOptimized: true, function: i32
> (i32)* @_Z3fooi, variables: !8)
> +!5 = !DISubroutineType(types: !6)
> +!6 = !{!7, !7}
> +!7 = !DIBasicType(name: "int", size: 32, align: 32, encoding:
> DW_ATE_signed)
> +!8 = !{!9}
> +!9 = !DILocalVariable(name: "i", arg: 1, scope: !4, file: !1, line: 1,
> type: !7)
> +!10 = !{i32 2, !"Dwarf Version", i32 4}
> +!11 = !{i32 2, !"Debug Info Version", i32 3}
> +!12 = !{!"clang version 3.8.0 (trunk 250915)"}
> +!13 = !{!14, !14, i64 0}
> +!14 = !{!"int", !15, i64 0}
> +!15 = !{!"omnipotent char", !16, i64 0}
> +!16 = !{!"Simple C/C++ TBAA"}
> +!17 = !DIExpression()
> +!18 = !DILocation(line: 1, column: 13, scope: !4)
> +!19 = !DILocation(line: 2, column: 7, scope: !20)
> +!20 = distinct !DILexicalBlock(scope: !4, file: !1, line: 2, column: 7)
> +!21 = !DILocation(line: 2, column: 9, scope: !20)
> +!22 = !DILocation(line: 2, column: 14, scope: !20)
> +!23 = !DILocation(line: 2, column: 17, scope: !20)
> +!24 = !DILocation(line: 2, column: 19, scope: !20)
> +!25 = !DILocation(line: 2, column: 7, scope: !4)
> +!26 = !DILocation(line: 2, column: 25, scope: !20)
> +!27 = !DILocation(line: 2, column: 42, scope: !20)
> +!28 = !DILocation(line: 3, column: 1, scope: !4)
> +
> +; CHECK: ![[THEN1]] = !DILocation(line: 2, column: 17, scope:
> ![[THENBLOCK:[0-9]+]])
> +; CHECK: ![[THENBLOCK]] = !DILexicalBlockFile({{.*}} discriminator: 2)
> +; CHECK: ![[THEN2]] = !DILocation(line: 2, column: 19, scope:
> ![[THENBLOCK]])
> +; CHECK: ![[THEN3]] = !DILocation(line: 2, column: 7, scope:
> ![[THENBLOCK]])
> +; CHECK: ![[ELSE]] = !DILocation(line: 2, column: 25, scope:
> ![[ELSEBLOCK:[0-9]+]])
> +; CHECK: ![[ELSEBLOCK]] = !DILexicalBlockFile({{.*}} discriminator: 1)
> +; CHECK: ![[COMBINE]] = !DILocation(line: 2, column: 42, scope:
> ![[COMBINEBLOCK:[0-9]+]])
> +; CHECK: ![[COMBINEBLOCK]] = !DILexicalBlockFile({{.*}} discriminator: 3)
>
>
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20151029/9e8f9450/attachment.html>
More information about the llvm-commits
mailing list