mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-23 11:13:28 +01:00
4f09faa3f6
Summary: Bug: https://bugs.llvm.org/show_bug.cgi?id=39024 The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here: A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins. B) Instructions in the middle block have different line numbers which give the impression of another iteration. In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks. I have set up a separate review D61933 for a fix which is required for this patch. Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse Reviewed By: hfinkel, jmorse Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits Tags: #llvm, #debug-info Differential Revision: https://reviews.llvm.org/D60831 > llvm-svn: 363046 llvm-svn: 363786
103 lines
4.3 KiB
LLVM
Executable File
103 lines
4.3 KiB
LLVM
Executable File
; Confirm that the line number for the for.body.preheader block
|
|
; branch is the the start of the loop.
|
|
|
|
; RUN: opt -simplifycfg -loop-simplify -S <%s | FileCheck %s
|
|
;
|
|
; CHECK: for.body.preheader:
|
|
; CHECK-NEXT: br label %for.body, !dbg ![[DL:[0-9]+]]
|
|
; CHECK: ![[DL]] = !DILocation(line: 8,
|
|
|
|
; This IR can be generated by running:
|
|
; clang src.cpp -O0 -g -S -emit-llvm -Xclang -disable-O0-optnone -o - | \
|
|
; opt -O2 -S -opt-bisect-limit=27 -o -
|
|
;
|
|
; Where src.cpp contains:
|
|
; int foo(int count, int *bar)
|
|
; {
|
|
; if (count + 1 > 256)
|
|
; return 0;
|
|
;
|
|
; int ret = count;
|
|
; int tmp;
|
|
; for (int j = 0; j < count; j++) {
|
|
; tmp = bar[j];
|
|
; ret += tmp;
|
|
; }
|
|
;
|
|
; return ret;
|
|
; }
|
|
|
|
define dso_local i32 @"foo"(i32 %count, i32* nocapture readonly %bar) local_unnamed_addr !dbg !8 {
|
|
entry:
|
|
%cmp = icmp sgt i32 %count, 255, !dbg !16
|
|
br i1 %cmp, label %return, label %for.cond.preheader, !dbg !16
|
|
|
|
for.cond.preheader: ; preds = %entry
|
|
%cmp16 = icmp slt i32 0, %count, !dbg !19
|
|
br i1 %cmp16, label %for.body.lr.ph, label %return.loopexit, !dbg !19
|
|
|
|
for.body.lr.ph: ; preds = %for.cond.preheader
|
|
br label %for.body, !dbg !19
|
|
|
|
for.body: ; preds = %for.body.lr.ph, %for.body
|
|
%j.08 = phi i32 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
|
|
%ret.07 = phi i32 [ %count, %for.body.lr.ph ], [ %add2, %for.body ]
|
|
%0 = zext i32 %j.08 to i64, !dbg !22
|
|
%arrayidx = getelementptr inbounds i32, i32* %bar, i64 %0, !dbg !22
|
|
%1 = load i32, i32* %arrayidx, align 4, !dbg !22
|
|
%add2 = add nsw i32 %1, %ret.07, !dbg !27
|
|
%inc = add nuw nsw i32 %j.08, 1, !dbg !28
|
|
%cmp1 = icmp slt i32 %inc, %count, !dbg !19
|
|
br i1 %cmp1, label %for.body, label %for.cond.return.loopexit_crit_edge, !dbg !19, !llvm.loop !29
|
|
|
|
for.cond.return.loopexit_crit_edge: ; preds = %for.body
|
|
%split = phi i32 [ %add2, %for.body ]
|
|
br label %return.loopexit, !dbg !19
|
|
|
|
return.loopexit: ; preds = %for.cond.return.loopexit_crit_edge, %for.cond.preheader
|
|
%ret.0.lcssa = phi i32 [ %split, %for.cond.return.loopexit_crit_edge ], [ %count, %for.cond.preheader ], !dbg !31
|
|
br label %return, !dbg !32
|
|
|
|
return: ; preds = %return.loopexit, %entry
|
|
%retval.0 = phi i32 [ 0, %entry ], [ %ret.0.lcssa, %return.loopexit ], !dbg !31
|
|
ret i32 %retval.0, !dbg !32
|
|
}
|
|
|
|
!llvm.dbg.cu = !{!0}
|
|
!llvm.module.flags = !{!3, !4, !5, !6}
|
|
!llvm.ident = !{!7}
|
|
|
|
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)
|
|
!1 = !DIFile(filename: "src.cpp", directory: "")
|
|
!2 = !{}
|
|
!3 = !{i32 2, !"CodeView", i32 1}
|
|
!4 = !{i32 2, !"Debug Info Version", i32 3}
|
|
!5 = !{i32 1, !"wchar_size", i32 2}
|
|
!6 = !{i32 7, !"PIC Level", i32 2}
|
|
!7 = !{!""}
|
|
!8 = distinct !DISubprogram(name: "foo", linkageName: "?foo@@YAHHPEAH@Z", scope: !1, file: !1, line: 1, type: !9, scopeLine: 2, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
|
|
!9 = !DISubroutineType(types: !10)
|
|
!10 = !{!11, !11, !12}
|
|
!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
|
|
!12 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !11, size: 64)
|
|
!13 = !DILocalVariable(name: "bar", arg: 2, scope: !8, file: !1, line: 1, type: !12)
|
|
!14 = !DILocation(line: 1, scope: !8)
|
|
!15 = !DILocalVariable(name: "count", arg: 1, scope: !8, file: !1, line: 1, type: !11)
|
|
!16 = !DILocation(line: 3, scope: !8)
|
|
!17 = !DILocalVariable(name: "j", scope: !18, file: !1, line: 8, type: !11)
|
|
!18 = distinct !DILexicalBlock(scope: !8, file: !1, line: 8)
|
|
!19 = !DILocation(line: 8, scope: !18)
|
|
!20 = !DILocalVariable(name: "ret", scope: !8, file: !1, line: 6, type: !11)
|
|
!21 = !DILocation(line: 6, scope: !8)
|
|
!22 = !DILocation(line: 9, scope: !23)
|
|
!23 = distinct !DILexicalBlock(scope: !24, file: !1, line: 8)
|
|
!24 = distinct !DILexicalBlock(scope: !18, file: !1, line: 8)
|
|
!25 = !DILocalVariable(name: "tmp", scope: !8, file: !1, line: 7, type: !11)
|
|
!26 = !DILocation(line: 7, scope: !8)
|
|
!27 = !DILocation(line: 10, scope: !23)
|
|
!28 = !DILocation(line: 8, scope: !24)
|
|
!29 = distinct !{!29, !19, !30}
|
|
!30 = !DILocation(line: 11, scope: !18)
|
|
!31 = !DILocation(line: 0, scope: !8)
|
|
!32 = !DILocation(line: 14, scope: !8)
|