1 files changed, 95 insertions, 0 deletions
diff --git a/test/DebugInfo/cross-cu-linkonce-distinct.ll b/test/DebugInfo/cross-cu-linkonce-distinct.ll
new file mode 100644
index 000000000000..2bd7c4718351
--- /dev/null
+++ b/test/DebugInfo/cross-cu-linkonce-distinct.ll
@@ -0,0 +1,95 @@
+; REQUIRES: object-emission
+
+; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck %s
+
+; Testing that two distinct (distinct by writing them in separate files, while
+; still fulfilling C++'s ODR by having identical token sequences) functions,
+; linked under LTO, get plausible debug info (and don't crash).
+
+; Built from source:
+; $ clang++ a.cpp b.cpp -g -c -emit-llvm
+; $ llvm-link a.bc b.bc -o ab.bc
+
+; This change is intended to tickle a case where the subprogram MDNode
+; associated with the llvm::Function will differ from the subprogram
+; referenced by the DbgLocs in the function.
+
+; $ sed -ie "s/!12, !0/!0, !12/" ab.ll
+; $ cat a.cpp
+; inline int func(int i) {
+;   return i * 2;
+; }
+; int (*x)(int) = &func;
+; $ cat b.cpp
+; inline int func(int i) {
+;   return i * 2;
+; }
+; int (*y)(int) = &func;
+
+; CHECK: DW_TAG_compile_unit
+; CHECK:   DW_TAG_subprogram
+; CHECK-NOT: DW_TAG
+; CHECK:     DW_AT_name {{.*}} "func"
+; CHECK: DW_TAG_compile_unit
+
+; FIXME: Maybe we should drop the subprogram here - since the function was
+; emitted in one CU, due to linkonce_odr uniquing. We certainly don't emit the
+; subprogram here if the source location for this definition is the same (see
+; test/DebugInfo/cross-cu-linkonce.ll), though it's very easy to tickle that
+; into failing even without duplicating the source as has been done in this
+; case (two cpp files in different directories, including the same header that
+; contains an inline function - clang will produce distinct subprogram metadata
+; that won't deduplicate owing to the file location information containing the
+; directory of the source file even though the file name is absolute, not
+; relative)
+
+; CHECK: DW_TAG_subprogram
+
+@x = global i32 (i32)* @_Z4funci, align 8
+@y = global i32 (i32)* @_Z4funci, align 8
+
+; Function Attrs: inlinehint nounwind uwtable
+define linkonce_odr i32 @_Z4funci(i32 %i) #0 {
+  %1 = alloca i32, align 4
+  store i32 %i, i32* %1, align 4
+  call void @llvm.dbg.declare(metadata i32* %1, metadata !22, metadata !{!"0x102"}), !dbg !23
+  %2 = load i32* %1, align 4, !dbg !24
+  %3 = mul nsw i32 %2, 2, !dbg !24
+  ret i32 %3, !dbg !24
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+attributes #0 = { inlinehint nounwind 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" }
+attributes #1 = { nounwind readnone }
+
+!llvm.dbg.cu = !{!12, !0}
+!llvm.module.flags = !{!19, !20}
+!llvm.ident = !{!21, !21}
+
+!0 = !{!"0x11\004\00clang version 3.5.0 \000\00\000\00\001", !1, !2, !2, !3, !9, !2} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/a.cpp] [DW_LANG_C_plus_plus]
+!1 = !{!"a.cpp", !"/tmp/dbginfo"}
+!2 = !{}
+!3 = !{!4}
+!4 = !{!"0x2e\00func\00func\00_Z4funci\001\000\001\000\006\00256\000\001", !1, !5, !6, null, i32 (i32)* @_Z4funci, null, null, !2} ; [ DW_TAG_subprogram ] [line 1] [def] [func]
+!5 = !{!"0x29", !1}          ; [ DW_TAG_file_type ] [/tmp/dbginfo/a.cpp]
+!6 = !{!"0x15\00\000\000\000\000\000\000", i32 0, null, null, !7, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
+!7 = !{!8, !8}
+!8 = !{!"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
+!9 = !{!10}
+!10 = !{!"0x34\00x\00x\00\004\000\001", null, !5, !11, i32 (i32)** @x, null} ; [ DW_TAG_variable ] [x] [line 4] [def]
+!11 = !{!"0xf\00\000\0064\0064\000\000", null, null, !6} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [from ]
+!12 = !{!"0x11\004\00clang version 3.5.0 \000\00\000\00\001", !13, !2, !2, !14, !17, !2} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/b.cpp] [DW_LANG_C_plus_plus]
+!13 = !{!"b.cpp", !"/tmp/dbginfo"}
+!14 = !{!15}
+!15 = !{!"0x2e\00func\00func\00_Z4funci\001\000\001\000\006\00256\000\001", !13, !16, !6, null, i32 (i32)* @_Z4funci, null, null, !2} ; [ DW_TAG_subprogram ] [line 1] [def] [func]
+!16 = !{!"0x29", !13}        ; [ DW_TAG_file_type ] [/tmp/dbginfo/b.cpp]
+!17 = !{!18}
+!18 = !{!"0x34\00y\00y\00\004\000\001", null, !16, !11, i32 (i32)** @y, null} ; [ DW_TAG_variable ] [y] [line 4] [def]
+!19 = !{i32 2, !"Dwarf Version", i32 4}
+!20 = !{i32 1, !"Debug Info Version", i32 2}
+!21 = !{!"clang version 3.5.0 "}
+!22 = !{!"0x101\00i\0016777217\000", !4, !5, !8} ; [ DW_TAG_arg_variable ] [i] [line 1]
+!23 = !MDLocation(line: 1, scope: !4)
+!24 = !MDLocation(line: 2, scope: !4)