Fix the bitcode upgrade for DIGlobalVariable in a DIImportedEntity context.

The bitcode upgrade for DIGlobalVariable unconditionally wrapped
DIGlobalVariables in a DIGlobalVariableExpression. When a
DIGlobalVariable is referenced by a DIImportedEntity, however, this is
wrong. This patch fixes the bitcode upgrade by deferring the creation
of DIGlobalVariableExpressions until we know the context of the
DIGlobalVariable.

<rdar://problem/30134279>

Differential Revision: https://reviews.llvm.org/D29349

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294318 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 16 insertions, 12 deletions

diff --git a/test/Bitcode/DIGlobalVariableExpression.ll b/test/Bitcode/DIGlobalVariableExpression.ll
index 0bb0488b131..f6796bbdb7a 100644
--- a/test/Bitcode/DIGlobalVariableExpression.ll
+++ b/test/Bitcode/DIGlobalVariableExpression.ll
@@ -7,12 +7,16 @@
 ; CHECK: @h = common global i32 0, align 4, !dbg ![[H:[0-9]+]]
 ; CHECK: ![[G]] = {{.*}}!DIGlobalVariableExpression(var: ![[GVAR:[0-9]+]], expr: ![[GEXPR:[0-9]+]])
 ; CHECK: ![[GVAR]] = distinct !DIGlobalVariable(name: "g",
+; CHECK: DICompileUnit({{.*}}, imports: ![[IMPORTS:[0-9]+]]
 ; CHECK: !DIGlobalVariableExpression(var: ![[CVAR:[0-9]+]], expr: ![[CEXPR:[0-9]+]])
 ; CHECK: ![[CVAR]] = distinct !DIGlobalVariable(name: "c",
 ; CHECK: ![[CEXPR]] = !DIExpression(DW_OP_constu, 23, DW_OP_stack_value)
-; CHECK: ![[H]] = {{.*}}!DIGlobalVariableExpression(var: ![[HVAR:[0-9]+]])
-; CHECK: ![[HVAR]] = distinct !DIGlobalVariable(name: "h",
+; CHECK: ![[HVAR:[0-9]+]] = distinct !DIGlobalVariable(name: "h",
+; CHECK: ![[IMPORTS]] = !{![[CIMPORT:[0-9]+]]}
+; CHECK: ![[CIMPORT]] = !DIImportedEntity({{.*}}entity: ![[HVAR]]
 ; CHECK: ![[GEXPR]] = !DIExpression(DW_OP_plus, 1)
+; CHECK: ![[H]] = {{.*}}!DIGlobalVariableExpression(var: ![[HVAR]])
+
 @g = common global i32 0, align 4, !dbg !0
 @h = common global i32 0, align 4, !dbg !11
 
@@ -21,9 +25,9 @@
 !llvm.ident = !{!9}
 
 !0 = distinct !DIGlobalVariable(name: "g", scope: !1, file: !2, line: 1, type: !5, isLocal: false, isDefinition: true, expr: !DIExpression(DW_OP_plus, 1))
-!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !2, producer: "clang version 4.0.0 (trunk 286129) (llvm/trunk 286128)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !3, globals: !4)
+!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !2, producer: "clang version 4.0.0 (trunk 286129) (llvm/trunk 286128)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !4, imports: !3)
 !2 = !DIFile(filename: "a.c", directory: "/")
-!3 = !{}
+!3 = !{!12}
 !4 = !{!0, !10, !11}
 !5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
 !6 = !{i32 2, !"Dwarf Version", i32 4}
@@ -32,3 +36,4 @@
 !9 = !{!"clang version 4.0.0 (trunk 286129) (llvm/trunk 286128)"}
 !10 = distinct !DIGlobalVariable(name: "c", scope: !1, file: !2, line: 1, type: !5, isLocal: false, isDefinition: true, expr: !DIExpression(DW_OP_constu, 23, DW_OP_stack_value))
 !11 = distinct !DIGlobalVariable(name: "h", scope: !1, file: !2, line: 2, type: !5, isLocal: false, isDefinition: true)
+!12 = !DIImportedEntity(tag: DW_TAG_imported_declaration, line: 1, scope: !1, entity: !11)
diff --git a/test/Bitcode/DIGlobalVariableExpression.ll.bc b/test/Bitcode/DIGlobalVariableExpression.ll.bc
index 54b6dbd6351..0eeb3aaca82 100644
--- a/test/Bitcode/DIGlobalVariableExpression.ll.bc
+++ b/test/Bitcode/DIGlobalVariableExpression.ll.bc
diff --git a/test/Bitcode/dityperefs-3.8.ll b/test/Bitcode/dityperefs-3.8.ll
index b032805bd28..09225d4eba3 100644
--- a/test/Bitcode/dityperefs-3.8.ll
+++ b/test/Bitcode/dityperefs-3.8.ll
@@ -18,14 +18,13 @@
 ; CHECK-NEXT: !7 = !DILocalVariable(name: "V1", scope: !6, type: !2)
 ; CHECK-NEXT: !8 = !DIObjCProperty(name: "P1", type: !1)
 ; CHECK-NEXT: !9 = !DITemplateTypeParameter(type: !1)
-; CHECK-NEXT: !10 = distinct !DIGlobalVariableExpression(var: !11)
-; CHECK-NEXT: !11 = !DIGlobalVariable(name: "G",{{.*}} type: !1,
-; CHECK-NEXT: !12 = !DITemplateValueParameter(type: !1, value: i32* @G1)
-; CHECK-NEXT: !13 = !DIImportedEntity(tag: DW_TAG_imported_module, name: "T2", scope: !0, entity: !1)
-; CHECK-NEXT: !14 = !DICompositeType(tag: DW_TAG_structure_type, name: "T3", file: !0, elements: !15, identifier: "T3")
-; CHECK-NEXT: !15 = !{!16}
-; CHECK-NEXT: !16 = !DISubprogram(scope: !14,
-; CHECK-NEXT: !17 = !DIDerivedType(tag: DW_TAG_ptr_to_member_type,{{.*}} extraData: !14)
+; CHECK-NEXT: !10 = !DIGlobalVariable(name: "G",{{.*}} type: !1,
+; CHECK-NEXT: !11 = !DITemplateValueParameter(type: !1, value: i32* @G1)
+; CHECK-NEXT: !12 = !DIImportedEntity(tag: DW_TAG_imported_module, name: "T2", scope: !0, entity: !1)
+; CHECK-NEXT: !13 = !DICompositeType(tag: DW_TAG_structure_type, name: "T3", file: !0, elements: !14, identifier: "T3")
+; CHECK-NEXT: !14 = !{!15}
+; CHECK-NEXT: !15 = !DISubprogram(scope: !13,
+; CHECK-NEXT: !16 = !DIDerivedType(tag: DW_TAG_ptr_to_member_type,{{.*}} extraData: !13)
 
 !0 = !DIFile(filename: "path/to/file", directory: "/path/to/dir")
 !1 = !DICompositeType(tag: DW_TAG_structure_type, name: "T1", file: !0, identifier: "T1")