[Unroll][DebugInfo] Propagate loop body's debug location to epilog preheader

NewExit and epilog PreHeader should has the same debug loc as the original loop
body, instead of original loop exit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321465 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 132 insertions, 2 deletions

diff --git a/test/Transforms/LoopUnroll/runtime-epilog-debuginfo.ll b/test/Transforms/LoopUnroll/runtime-epilog-debuginfo.ll
new file mode 100644
index 00000000000..28db1c83406
--- /dev/null
+++ b/test/Transforms/LoopUnroll/runtime-epilog-debuginfo.ll
@@ -0,0 +1,128 @@
+; RUN: opt -loop-unroll -unroll-runtime -unroll-runtime-epilog -S %s | FileCheck %s
+
+; Test that epilogue is tagged with the same debug information as original loop body rather than original loop exit.
+
+; CHECK: for.body.i:
+; CHECK:   br i1 {{.*}}, label %lee1.exit.loopexit.unr-lcssa.loopexit, label %for.body.i, !dbg ![[LOOP_LOC:[0-9]+]]
+; CHECK: lee1.exit.loopexit.unr-lcssa.loopexit:
+; CHECK:   br label %lee1.exit.loopexit.unr-lcssa, !dbg ![[LOOP_LOC]]
+; CHECK: lee1.exit.loopexit.unr-lcssa:
+; CHECK:   %lcmp.mod = icmp ne i32 %xtraiter, 0, !dbg ![[LOOP_LOC]]
+; CHECK:   br i1 %lcmp.mod, label %for.body.i.epil.preheader, label %lee1.exit.loopexit, !dbg ![[LOOP_LOC]]
+; CHECK: for.body.i.epil.preheader:
+; CHECK:   br label %for.body.i.epil, !dbg ![[LOOP_LOC]]
+; CHECK: lee1.exit.loopexit:
+; CHECK:   br label %lee1.exit, !dbg ![[EXIT_LOC:[0-9]+]]
+
+; CHECK-DAG: ![[LOOP_LOC]] = !DILocation(line: 5, column: 3, scope: !{{.*}}, inlinedAt: !{{.*}})
+; CHECK-DAG: ![[EXIT_LOC]] = !DILocation(line: 11, column: 12, scope: !{{.*}}, inlinedAt: !{{.*}})
+
+; Function Attrs: nounwind readnone
+define i32 @goo(i32 %a, i32 %b) local_unnamed_addr #0 !dbg !8 {
+entry:
+  tail call void @llvm.dbg.value(metadata i32 %a, i64 0, metadata !13, metadata !15), !dbg !16
+  tail call void @llvm.dbg.value(metadata i32 %b, i64 0, metadata !14, metadata !15), !dbg !17
+  tail call void @llvm.dbg.value(metadata i32 %a, i64 0, metadata !18, metadata !15), !dbg !26
+  tail call void @llvm.dbg.value(metadata i32 %b, i64 0, metadata !21, metadata !15), !dbg !28
+  tail call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !22, metadata !15), !dbg !29
+  tail call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !23, metadata !15), !dbg !30
+  tail call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !23, metadata !15), !dbg !30
+  tail call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !22, metadata !15), !dbg !29
+  %cmp7.i = icmp eq i32 %b, 0, !dbg !31
+  br i1 %cmp7.i, label %lee1.exit, label %for.body.i.preheader, !dbg !33
+
+for.body.i.preheader:                             ; preds = %entry
+  br label %for.body.i, !dbg !34
+
+for.body.i:                                       ; preds = %for.body.i.preheader, %for.body.i
+  %i.09.i = phi i32 [ %inc.i, %for.body.i ], [ 0, %for.body.i.preheader ]
+  %t.08.i = phi i32 [ %add1.i, %for.body.i ], [ 0, %for.body.i.preheader ]
+  %div.i = sdiv i32 %t.08.i, 2, !dbg !34
+  %add.i = add i32 %t.08.i, %a, !dbg !35
+  %add1.i = add i32 %add.i, %div.i, !dbg !36
+  tail call void @llvm.dbg.value(metadata i32 %add1.i, i64 0, metadata !22, metadata !15), !dbg !29
+  %inc.i = add nuw i32 %i.09.i, 1, !dbg !37
+  tail call void @llvm.dbg.value(metadata i32 %inc.i, i64 0, metadata !23, metadata !15), !dbg !30
+  tail call void @llvm.dbg.value(metadata i32 %inc.i, i64 0, metadata !23, metadata !15), !dbg !30
+  tail call void @llvm.dbg.value(metadata i32 %add1.i, i64 0, metadata !22, metadata !15), !dbg !29
+  %exitcond.i = icmp eq i32 %inc.i, %b, !dbg !31
+  br i1 %exitcond.i, label %lee1.exit.loopexit, label %for.body.i, !dbg !33, !llvm.loop !38
+
+lee1.exit.loopexit:                               ; preds = %for.body.i
+  %add1.i.lcssa = phi i32 [ %add1.i, %for.body.i ]
+  br label %lee1.exit, !dbg !41
+
+lee1.exit:                                        ; preds = %lee1.exit.loopexit, %entry
+  %t.0.lcssa.i = phi i32 [ 0, %entry ], [ %add1.i.lcssa, %lee1.exit.loopexit ]
+  tail call void @llvm.dbg.value(metadata i32 %a, i64 0, metadata !44, metadata !15), !dbg !47
+  tail call void @llvm.dbg.value(metadata i32 %b, i64 0, metadata !45, metadata !15), !dbg !48
+  %add.i4 = add nsw i32 %b, %a, !dbg !41
+  %sub.i = sub nsw i32 %a, %b, !dbg !49
+  %mul.i = mul nsw i32 %add.i4, %sub.i, !dbg !50
+  %add = add nsw i32 %t.0.lcssa.i, %mul.i, !dbg !51
+  ret i32 %add, !dbg !52
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1
+
+attributes #0 = { nounwind readnone "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="arm7tdmi" "target-features"="+neon,+strict-align,+vfp3,-crypto,-d16,-fp-armv8,-fp-only-sp,-fp16,-vfp4" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5, !6}
+!llvm.ident = !{!7}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "Snapdragon LLVM ARM Compiler 4.0.5 (based on llvm.org 4.0+)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "t.c", directory: "/prj/llvm-arm/scratch1/zhaoshiz/bugs/debug-symbol")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{i32 1, !"min_enum_size", i32 4}
+!7 = !{!"Snapdragon LLVM ARM Compiler 4.0.5 (based on llvm.org 4.0+)"}
+!8 = distinct !DISubprogram(name: "goo", scope: !1, file: !1, line: 23, type: !9, isLocal: false, isDefinition: true, scopeLine: 23, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !12)
+!9 = !DISubroutineType(types: !10)
+!10 = !{!11, !11, !11}
+!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!12 = !{!13, !14}
+!13 = !DILocalVariable(name: "a", arg: 1, scope: !8, file: !1, line: 23, type: !11)
+!14 = !DILocalVariable(name: "b", arg: 2, scope: !8, file: !1, line: 23, type: !11)
+!15 = !DIExpression()
+!16 = !DILocation(line: 23, column: 14, scope: !8)
+!17 = !DILocation(line: 23, column: 21, scope: !8)
+!18 = !DILocalVariable(name: "a", arg: 1, scope: !19, file: !1, line: 3, type: !11)
+!19 = distinct !DISubprogram(name: "lee1", scope: !1, file: !1, line: 3, type: !9, isLocal: true, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !20)
+!20 = !{!18, !21, !22, !23}
+!21 = !DILocalVariable(name: "b", arg: 2, scope: !19, file: !1, line: 3, type: !11)
+!22 = !DILocalVariable(name: "t", scope: !19, file: !1, line: 4, type: !11)
+!23 = !DILocalVariable(name: "i", scope: !24, file: !1, line: 5, type: !25)
+!24 = distinct !DILexicalBlock(scope: !19, file: !1, line: 5, column: 3)
+!25 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned)
+!26 = !DILocation(line: 3, column: 22, scope: !19, inlinedAt: !27)
+!27 = distinct !DILocation(line: 24, column: 27, scope: !8)
+!28 = !DILocation(line: 3, column: 29, scope: !19, inlinedAt: !27)
+!29 = !DILocation(line: 4, column: 7, scope: !19, inlinedAt: !27)
+!30 = !DILocation(line: 5, column: 17, scope: !24, inlinedAt: !27)
+!31 = !DILocation(line: 5, column: 23, scope: !32, inlinedAt: !27)
+!32 = distinct !DILexicalBlock(scope: !24, file: !1, line: 5, column: 3)
+!33 = !DILocation(line: 5, column: 3, scope: !24, inlinedAt: !27)
+!34 = !DILocation(line: 6, column: 13, scope: !32, inlinedAt: !27)
+!35 = !DILocation(line: 6, column: 11, scope: !32, inlinedAt: !27)
+!36 = !DILocation(line: 6, column: 7, scope: !32, inlinedAt: !27)
+!37 = !DILocation(line: 5, column: 28, scope: !32, inlinedAt: !27)
+!38 = distinct !{!38, !39, !40}
+!39 = !DILocation(line: 5, column: 3, scope: !24)
+!40 = !DILocation(line: 6, column: 14, scope: !24)
+!41 = !DILocation(line: 11, column: 12, scope: !42, inlinedAt: !46)
+!42 = distinct !DISubprogram(name: "lee2", scope: !1, file: !1, line: 10, type: !9, isLocal: true, isDefinition: true, scopeLine: 10, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !43)
+!43 = !{!44, !45}
+!44 = !DILocalVariable(name: "a", arg: 1, scope: !42, file: !1, line: 10, type: !11)
+!45 = !DILocalVariable(name: "b", arg: 2, scope: !42, file: !1, line: 10, type: !11)
+!46 = distinct !DILocation(line: 24, column: 40, scope: !8)
+!47 = !DILocation(line: 10, column: 22, scope: !42, inlinedAt: !46)
+!48 = !DILocation(line: 10, column: 29, scope: !42, inlinedAt: !46)
+!49 = !DILocation(line: 11, column: 20, scope: !42, inlinedAt: !46)
+!50 = !DILocation(line: 11, column: 16, scope: !42, inlinedAt: !46)
+!51 = !DILocation(line: 24, column: 38, scope: !8)
+!52 = !DILocation(line: 24, column: 3, scope: !8)
diff --git a/test/Transforms/LoopUnroll/runtime-loop1.ll b/test/Transforms/LoopUnroll/runtime-loop1.ll
index d180980c95b..32463373ca9 100644
--- a/test/Transforms/LoopUnroll/runtime-loop1.ll
+++ b/test/Transforms/LoopUnroll/runtime-loop1.ll
@@ -13,9 +13,11 @@
 ; EPILOG:   br i1 %niter.ncmp.1, label %for.end.loopexit.unr-lcssa.loopexit, label %for.body, !dbg [[BODY_LOC:![0-9]+]]
 ; EPILOG-NOT: br i1 %niter.ncmp.2, label %for.end.loopexit{{.*}}, label %for.body
 ; EPILOG: for.body.epil.preheader:
-; EPILOG:   br label %for.body.epil, !dbg [[EXIT_LOC:![0-9]+]]
+; EPILOG:   br label %for.body.epil, !dbg [[BODY_LOC]]
 ; EPILOG: for.body.epil:
-; EPILOG:   br label %for.end.loopexit.epilog-lcssa, !dbg [[BODY_LOC:![0-9]+]]
+; EPILOG:   br label %for.end.loopexit.epilog-lcssa, !dbg [[BODY_LOC]]
+; EPILOG: for.end.loopexit:
+; EPILOG:   br label %for.end, !dbg [[EXIT_LOC:![0-9]+]]
 
 ; EPILOG-DAG: [[PH_LOC]] = !DILocation(line: 101, column: 1, scope: !{{.*}})
 ; EPILOG-DAG: [[BODY_LOC]] = !DILocation(line: 102, column: 1, scope: !{{.*}})