DebugInfo: Simplify subprogram declaration creation/references and accidentally refix PR11300.

Also simplifies the linkage name handling a little too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209311 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 36 insertions, 38 deletions

diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index f09cb6ade6..8382990a6c 100644
--- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -1384,40 +1384,37 @@ DIE *DwarfUnit::getOrCreateSubprogramDIE(DISubprogram SP) {
   if (DIE *SPDie = getDIE(SP))
     return SPDie;
 
-  DISubprogram SPDecl = SP.getFunctionDeclaration();
-  if (SPDecl.isSubprogram())
+  DIE *DeclDie = nullptr;
+  StringRef DeclLinkageName;
+  if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
     // Add subprogram definitions to the CU die directly.
     ContextDIE = &getUnitDie();
+    DeclDie = getOrCreateSubprogramDIE(SPDecl);
+    DeclLinkageName = SPDecl.getLinkageName();
+  }
 
   // DW_TAG_inlined_subroutine may refer to this DIE.
   DIE &SPDie = createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, SP);
 
-  DIE *DeclDie = nullptr;
-  if (SPDecl.isSubprogram())
-    DeclDie = getOrCreateSubprogramDIE(SPDecl);
 
   // Add function template parameters.
   addTemplateParams(SPDie, SP.getTemplateParams());
 
-  if (DeclDie)
-    // Refer function declaration directly.
-    addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
-
   // Add the linkage name if we have one and it isn't in the Decl.
   StringRef LinkageName = SP.getLinkageName();
-  if (!LinkageName.empty()) {
-    if (SPDecl.isSubprogram() && !SPDecl.getLinkageName().empty())
-      assert(SPDecl.getLinkageName() == SP.getLinkageName() &&
-             "decl has a linkage name and it is different");
-    else
-      addString(SPDie, dwarf::DW_AT_MIPS_linkage_name,
-                GlobalValue::getRealLinkageName(LinkageName));
-  }
-
-  // If this DIE is going to refer declaration info using AT_specification
-  // then there is no need to add other attributes.
-  if (DeclDie)
+  assert(((LinkageName.empty() || DeclLinkageName.empty()) ||
+          LinkageName == DeclLinkageName) &&
+         "decl has a linkage name and it is different");
+  if (!LinkageName.empty() && DeclLinkageName.empty())
+    addString(SPDie, dwarf::DW_AT_MIPS_linkage_name,
+              GlobalValue::getRealLinkageName(LinkageName));
+
+  if (DeclDie) {
+    // Refer to the function declaration where all the other attributes will be
+    // found.
+    addDIEEntry(SPDie, dwarf::DW_AT_specification, *DeclDie);
     return &SPDie;
+  }
 
   // Constructors and operators for anonymous aggregates do not have names.
   if (!SP.getName().empty())
diff --git a/test/DebugInfo/X86/DW_AT_linkage_name.ll b/test/DebugInfo/X86/DW_AT_linkage_name.ll
index 4aa69f2aa2..76d3abbe35 100644
--- a/test/DebugInfo/X86/DW_AT_linkage_name.ll
+++ b/test/DebugInfo/X86/DW_AT_linkage_name.ll
@@ -18,12 +18,12 @@
 ; Test that we do emit a linkage name for a specific instance of it.
 
 ; CHECK: DW_TAG_subprogram
-; CHECK: [[A:.*]]:     DW_TAG_subprogram
+; CHECK: [[A_DTOR:.*]]:     DW_TAG_subprogram
 ; CHECK: DW_AT_name {{.*}} "~A"
 ; CHECK-NOT: DW_AT_MIPS_linkage_name
 ; CHECK: DW_TAG_subprogram
-; CHECK-NEXT:  DW_AT_specification {{.*}}[[A]]
 ; CHECK-NEXT: DW_AT_MIPS_linkage_name {{.*}} "_ZN1AD2Ev"
+; CHECK-NEXT: DW_AT_specification {{.*}}[[A_DTOR]]
 
 
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
diff --git a/test/DebugInfo/X86/DW_AT_specification.ll b/test/DebugInfo/X86/DW_AT_specification.ll
index 64b00800d6..b93cdf081d 100644
--- a/test/DebugInfo/X86/DW_AT_specification.ll
+++ b/test/DebugInfo/X86/DW_AT_specification.ll
@@ -3,10 +3,10 @@
 
 ; test that the DW_AT_specification is a back edge in the file.
 
-; CHECK: DW_TAG_subprogram [{{[0-9]+}}] *
-; CHECK: DW_AT_specification [DW_FORM_ref4]      (cu + 0x[[OFFSET:[0-9a-f]*]] => {0x0000[[OFFSET]]})
-; CHECK: 0x0000[[OFFSET]]: DW_TAG_subprogram [{{[0-9]+}}] *
-; CHECK: DW_AT_name [DW_FORM_strp]	( .debug_str[0x{{[0-9a-f]*}}] = "bar")
+; CHECK: [[BAR_DECL:0x[0-9a-f]*]]: DW_TAG_subprogram
+; CHECK-NEXT: DW_AT_MIPS_linkage_name {{.*}} "_ZN3foo3barEv"
+; CHECK: DW_TAG_subprogram
+; CHECK-NEXT: DW_AT_specification {{.*}} {[[BAR_DECL]]}
 
 
 @_ZZN3foo3barEvE1x = constant i32 0, align 4
diff --git a/test/DebugInfo/X86/concrete_out_of_line.ll b/test/DebugInfo/X86/concrete_out_of_line.ll
index ae025ad0de..baa819de85 100644
--- a/test/DebugInfo/X86/concrete_out_of_line.ll
+++ b/test/DebugInfo/X86/concrete_out_of_line.ll
@@ -11,8 +11,12 @@
 ; CHECK:   DW_TAG_subprogram
 ; CHECK: [[ASSIGN_DECL:0x........]]:  DW_TAG_subprogram
 
+; CHECK: DW_TAG_class_type
+; CHECK: [[RELEASE_DECL:0x........]]:  DW_TAG_subprogram
+; CHECK: [[DTOR_DECL:0x........]]:  DW_TAG_subprogram
+
 ; CHECK: [[RELEASE:0x........]]: DW_TAG_subprogram
-; CHECK-NEXT:     DW_AT_specification {{.*}} {[[RELEASE_DECL:0x........]]}
+; CHECK:     DW_AT_specification {{.*}} {[[RELEASE_DECL]]}
 ; CHECK: DW_TAG_formal_parameter
 ; CHECK-NOT: NULL
 ; CHECK-NOT: DW_TAG
@@ -30,19 +34,14 @@
 ; CHECK: DW_TAG_inlined_subroutine
 ; CHECK-NEXT: DW_AT_abstract_origin {{.*}} {[[D2_ABS:0x........]]}
 
-; CHECK: DW_TAG_class_type
-; CHECK: [[RELEASE_DECL]]:  DW_TAG_subprogram
-; CHECK: [[DTOR_DECL:0x........]]:  DW_TAG_subprogram
-
-
 ; CHECK: [[D1_ABS]]: DW_TAG_subprogram
-; CHECK-NEXT:     DW_AT_specification {{.*}} {[[DTOR_DECL]]}
 ; CHECK-NEXT:     DW_AT_{{.*}}linkage_name
+; CHECK-NEXT:     DW_AT_specification {{.*}} {[[DTOR_DECL]]}
 ; CHECK-NEXT:     DW_AT_inline
 ; CHECK-NOT:     DW_AT_inline
 ; CHECK: [[D2_ABS]]: DW_TAG_subprogram
-; CHECK-NEXT:     DW_AT_specification {{.*}} {[[DTOR_DECL]]}
 ; CHECK-NEXT:     DW_AT_{{.*}}linkage_name
+; CHECK-NEXT:     DW_AT_specification {{.*}} {[[DTOR_DECL]]}
 ; CHECK-NEXT:     DW_AT_inline
 ; CHECK-NOT:     DW_AT_inline
 ; CHECK: DW_TAG
diff --git a/test/DebugInfo/X86/pr11300.ll b/test/DebugInfo/X86/pr11300.ll
index 772861a69b..b3c911252d 100644
--- a/test/DebugInfo/X86/pr11300.ll
+++ b/test/DebugInfo/X86/pr11300.ll
@@ -3,11 +3,13 @@
 
 ; test that the DW_AT_specification is a back edge in the file.
 
+; Skip the definition of zed(foo*)
 ; CHECK: DW_TAG_subprogram
-; CHECK: DW_AT_name [DW_FORM_strp]	( .debug_str[0x{{[0-9a-f]*}}] = "zed")
+; CHECK: DW_TAG_class_type
+; CHECK: [[BAR_DECL:0x[0-9a-f]*]]:     DW_TAG_subprogram
+; CHECK:     DW_AT_MIPS_linkage_name {{.*}} "_ZN3foo3barEv"
 ; CHECK: DW_TAG_subprogram
-; CHECK-NEXT: DW_AT_specification [DW_FORM_ref4]      (cu + {{.*}} => {[[BACK:0x[0-9a-f]*]]})
-; CHECK: [[BACK]]:     DW_TAG_subprogram
+; CHECK-NEXT: DW_AT_specification {{.*}} {[[BAR_DECL]]}
 
 %struct.foo = type { i8 }