DebugInfo: Remove MDString-based type references

Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*.  It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType.  The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata.  Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

  http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296

1 files changed, 7 insertions, 7 deletions

diff --git a/llvm/test/DebugInfo/Generic/virtual-index.ll b/llvm/test/DebugInfo/Generic/virtual-index.ll
index 68973bc4369..010f2ba5226 100644
--- a/llvm/test/DebugInfo/Generic/virtual-index.ll
+++ b/llvm/test/DebugInfo/Generic/virtual-index.ll
@@ -42,7 +42,7 @@ define void @_ZN1A1gEv(%struct.A* %this) unnamed_addr !dbg !19 {
 !1 = !DIFile(filename: "x", directory: "x")
 !2 = !{}
 !3 = !{!4}
-!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "A", file: !1, line: 1, size: 64, align: 64, elements: !5, vtableHolder: !"_ZTS1A", identifier: "_ZTS1A")
+!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "A", file: !1, line: 1, size: 64, align: 64, elements: !5, vtableHolder: !4, identifier: "_ZTS1A")
 !5 = !{!6, !12, !16}
 !6 = !DIDerivedType(tag: DW_TAG_member, name: "_vptr$A", scope: !1, file: !1, baseType: !7, size: 64, flags: DIFlagArtificial)
 !7 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !8, size: 64)
@@ -50,18 +50,18 @@ define void @_ZN1A1gEv(%struct.A* %this) unnamed_addr !dbg !19 {
 !9 = !DISubroutineType(types: !10)
 !10 = !{!11}
 !11 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
-!12 = !DISubprogram(name: "f", linkageName: "_ZN1A1fEv", scope: !"_ZTS1A", file: !1, line: 2, type: !13, isLocal: false, isDefinition: false, scopeLine: 2, containingType: !"_ZTS1A", virtuality: DW_VIRTUALITY_virtual, virtualIndex: 0, flags: DIFlagPrototyped, isOptimized: false)
+!12 = !DISubprogram(name: "f", linkageName: "_ZN1A1fEv", scope: !4, file: !1, line: 2, type: !13, isLocal: false, isDefinition: false, scopeLine: 2, containingType: !4, virtuality: DW_VIRTUALITY_virtual, virtualIndex: 0, flags: DIFlagPrototyped, isOptimized: false)
 !13 = !DISubroutineType(types: !14)
 !14 = !{null, !15}
-!15 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !"_ZTS1A", size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
-!16 = !DISubprogram(name: "g", linkageName: "_ZN1A1gEv", scope: !"_ZTS1A", file: !1, line: 3, type: !13, isLocal: false, isDefinition: false, scopeLine: 3, containingType: !"_ZTS1A", virtuality: DW_VIRTUALITY_virtual, virtualIndex: 4294967295, flags: DIFlagPrototyped, isOptimized: false)
-!18 = distinct !DISubprogram(name: "f", linkageName: "_ZN1A1fEv", scope: !"_ZTS1A", file: !1, line: 6, type: !13, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, declaration: !12, variables: !2)
-!19 = distinct !DISubprogram(name: "g", linkageName: "_ZN1A1gEv", scope: !"_ZTS1A", file: !1, line: 7, type: !13, isLocal: false, isDefinition: true, scopeLine: 7, flags: DIFlagPrototyped, isOptimized: false, unit: !0, declaration: !16, variables: !2)
+!15 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !4, size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
+!16 = !DISubprogram(name: "g", linkageName: "_ZN1A1gEv", scope: !4, file: !1, line: 3, type: !13, isLocal: false, isDefinition: false, scopeLine: 3, containingType: !4, virtuality: DW_VIRTUALITY_virtual, virtualIndex: 4294967295, flags: DIFlagPrototyped, isOptimized: false)
+!18 = distinct !DISubprogram(name: "f", linkageName: "_ZN1A1fEv", scope: !4, file: !1, line: 6, type: !13, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, declaration: !12, variables: !2)
+!19 = distinct !DISubprogram(name: "g", linkageName: "_ZN1A1gEv", scope: !4, file: !1, line: 7, type: !13, isLocal: false, isDefinition: true, scopeLine: 7, flags: DIFlagPrototyped, isOptimized: false, unit: !0, declaration: !16, variables: !2)
 !20 = !{i32 2, !"Dwarf Version", i32 4}
 !21 = !{i32 2, !"Debug Info Version", i32 3}
 !22 = !{!"clang version 3.9.0 (trunk 263469) (llvm/trunk 263156)"}
 !23 = !DILocalVariable(name: "this", arg: 1, scope: !18, type: !24, flags: DIFlagArtificial | DIFlagObjectPointer)
-!24 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !"_ZTS1A", size: 64, align: 64)
+!24 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !4, size: 64, align: 64)
 !25 = !DIExpression()
 !26 = !DILocation(line: 0, scope: !18)
 !27 = !DILocation(line: 6, column: 14, scope: !18)