Avoid using relocations for ref_addr in .dwo files

In dwo files the fixed offset can be used - if the dwos are linked into
a dwp, the dwo consumer must use the dwp tables to find out where the
original range of the debug_info was and resolve the "section relative"
value relative to that original range - effectively
avoiding/reimplementing the relocation handling.

llvm-svn: 301072

1 files changed, 46 insertions, 0 deletions

diff --git a/llvm/test/DebugInfo/X86/split-dwarf-cross-unit-reference.ll b/llvm/test/DebugInfo/X86/split-dwarf-cross-unit-reference.ll
new file mode 100644
index 00000000000..89222596a6d
--- /dev/null
+++ b/llvm/test/DebugInfo/X86/split-dwarf-cross-unit-reference.ll
@@ -0,0 +1,46 @@
+; RUN: llc -split-dwarf-file=foo.dwo -filetype=obj -o - < %s | llvm-objdump -r - | FileCheck %s
+
+; CHECK-NOT: .rela.debug_info.dwo
+; CHECK: RELOCATION RECORDS FOR [.rela.debug_info]:
+; CHECK-NOT: RELOCATION RECORDS
+; Expect one relocation in debug_info, between f3 and f1.
+; CHECK: R_X86_64_32 .debug_info
+; CHECK-NOT: .debug_info
+; CHECK: RELOCATION RECORDS
+; CHECK-NOT: .rela.debug_info.dwo
+
+
+; Function Attrs: noinline nounwind optnone uwtable
+define void @_Z2f1v() !dbg !7 {
+entry:
+  ret void, !dbg !10
+}
+
+; Function Attrs: noinline uwtable
+define void @_Z2f3v() !dbg !13 {
+entry:
+  call void @_Z2f1v(), !dbg !14
+  ret void, !dbg !16
+}
+
+!llvm.dbg.cu = !{!0, !3}
+!llvm.ident = !{!5, !5}
+!llvm.module.flags = !{!6}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 5.0.0 (trunk 301051) (llvm/trunk 301062)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "a.cpp", directory: "/usr/local/google/home/blaikie/dev/scratch")
+!2 = !{}
+!3 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !4, producer: "clang version 5.0.0 (trunk 301051) (llvm/trunk 301062)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!4 = !DIFile(filename: "b.cpp", directory: "/usr/local/google/home/blaikie/dev/scratch")
+!5 = !{!"clang version 5.0.0 (trunk 301051) (llvm/trunk 301062)"}
+!6 = !{i32 2, !"Debug Info Version", i32 3}
+!7 = distinct !DISubprogram(name: "f1", linkageName: "_Z2f1v", scope: !1, file: !1, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!8 = !DISubroutineType(types: !9)
+!9 = !{null}
+!10 = !DILocation(line: 1, scope: !7)
+!11 = distinct !DISubprogram(name: "f2", linkageName: "_Z2f2v", scope: !1, file: !1, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!12 = !DILocation(line: 1, scope: !11)
+!13 = distinct !DISubprogram(name: "f3", linkageName: "_Z2f3v", scope: !4, file: !4, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, unit: !3, variables: !2)
+!14 = !DILocation(line: 1, scope: !11, inlinedAt: !15)
+!15 = distinct !DILocation(line: 1, scope: !13)
+!16 = !DILocation(line: 1, scope: !13)