[llvm] r274400 - [CodeView] Include the offset of nested members

[David Majnemer via llvm-commits]

Author: majnemer
Date: Fri Jul  1 18:12:48 2016
New Revision: 274400

URL: http://llvm.org/viewvc/llvm-project?rev=274400&view=rev
Log:
[CodeView] Include the offset of nested members

Given something like:
  struct S {
    int a;
    struct { int b; };
  };

We would fail to give 'b' offset 4.  Instead, we would give it the
offset it has inside of it's struct.

Added:
    llvm/trunk/test/DebugInfo/COFF/anonymous-struct.ll
Modified:
    llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp?rev=274400&r1=274399&r2=274400&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp Fri Jul  1 18:12:48 2016
@@ -1378,7 +1378,7 @@ TypeIndex CodeViewDebug::lowerTypeEnum(c
 struct llvm::ClassInfo {
   struct MemberInfo {
     const DIDerivedType *MemberTypeNode;
-    unsigned BaseOffset;
+    uint64_t BaseOffset;
   };
   // [MemberInfo]
   typedef std::vector<MemberInfo> MemberList;
@@ -1416,7 +1416,7 @@ void CodeViewDebug::collectMemberInfo(Cl
   // An unnamed member must represent a nested struct or union. Add all the
   // indirect fields to the current record.
   assert((DDTy->getOffsetInBits() % 8) == 0 && "Unnamed bitfield member!");
-  unsigned Offset = DDTy->getOffsetInBits() / 8;
+  uint64_t Offset = DDTy->getOffsetInBits();
   const DIType *Ty = DDTy->getBaseType().resolve();
   const DICompositeType *DCTy = cast<DICompositeType>(Ty);
   ClassInfo NestedInfo = collectClassInfo(DCTy);
@@ -1578,12 +1578,13 @@ CodeViewDebug::lowerRecordFieldList(cons
     }
 
     // Data member.
-    uint64_t MemberOffsetInBits = Member->getOffsetInBits();
+    uint64_t MemberOffsetInBits =
+        Member->getOffsetInBits() + MemberInfo.BaseOffset;
     if (Member->isBitField()) {
       uint64_t StartBitOffset = MemberOffsetInBits;
       if (const auto *CI =
               dyn_cast_or_null<ConstantInt>(Member->getStorageOffsetInBits())) {
-        MemberOffsetInBits = CI->getZExtValue();
+        MemberOffsetInBits = CI->getZExtValue() + MemberInfo.BaseOffset;
       }
       StartBitOffset -= MemberOffsetInBits;
       MemberBaseType = TypeTable.writeBitField(BitFieldRecord(

Added: llvm/trunk/test/DebugInfo/COFF/anonymous-struct.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/COFF/anonymous-struct.ll?rev=274400&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/COFF/anonymous-struct.ll (added)
+++ llvm/trunk/test/DebugInfo/COFF/anonymous-struct.ll Fri Jul  1 18:12:48 2016
@@ -0,0 +1,61 @@
+; RUN: llc < %s -filetype=obj | llvm-readobj - -codeview | FileCheck %s
+
+; C++ source to regenerate:
+; struct S {
+;   int x;
+;   struct { int a; } ;
+; } s;
+
+; CHECK: CodeViewTypes [
+; CHECK:  FieldList ([[S_fl:.*]]) {
+; CHECK:    TypeLeafKind: LF_FIELDLIST (0x1203)
+; CHECK:    DataMember {
+; CHECK:      Type: int (0x74)
+; CHECK:      FieldOffset: 0x0
+; CHECK:      Name: x
+; CHECK:    }
+; CHECK:    DataMember {
+; CHECK:      Type: int (0x74)
+; CHECK:      FieldOffset: 0x4
+; CHECK:      Name: a
+; CHECK:    }
+; CHECK:  }
+; CHECK:  Struct ({{.*}}) {
+; CHECK:    TypeLeafKind: LF_STRUCTURE (0x1505)
+; CHECK:    MemberCount: 2
+; CHECK:    Properties [ (0x0)
+; CHECK:    ]
+; CHECK:    FieldList: <field list> ([[S_fl]])
+; CHECK:    SizeOf: 8
+; CHECK:    Name: S
+; CHECK:  }
+
+target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
+target triple = "i686-pc-windows-msvc18.0.0"
+
+%struct.S = type { i32, %struct.anon }
+%struct.anon = type { i32 }
+
+ at s = common global %struct.S zeroinitializer, align 4
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!14, !15}
+!llvm.ident = !{!16}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.9.0 (trunk 274261) (llvm/trunk 274262)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, globals: !3)
+!1 = !DIFile(filename: "-", directory: "/usr/local/google/home/majnemer/llvm/src")
+!2 = !{}
+!3 = !{!4}
+!4 = distinct !DIGlobalVariable(name: "s", scope: !0, file: !5, line: 5, type: !6, isLocal: false, isDefinition: true, variable: %struct.S* @s)
+!5 = !DIFile(filename: "<stdin>", directory: "/usr/local/google/home/majnemer/llvm/src")
+!6 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "S", file: !5, line: 2, size: 64, align: 32, elements: !7)
+!7 = !{!8, !10}
+!8 = !DIDerivedType(tag: DW_TAG_member, name: "x", scope: !6, file: !5, line: 3, baseType: !9, size: 32, align: 32)
+!9 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!10 = !DIDerivedType(tag: DW_TAG_member, scope: !6, file: !5, line: 4, baseType: !11, size: 32, align: 32, offset: 32)
+!11 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !6, file: !5, line: 4, size: 32, align: 32, elements: !12)
+!12 = !{!13}
+!13 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !11, file: !5, line: 4, baseType: !9, size: 32, align: 32)
+!14 = !{i32 2, !"CodeView", i32 1}
+!15 = !{i32 2, !"Debug Info Version", i32 3}
+!16 = !{!"clang version 3.9.0 (trunk 274261) (llvm/trunk 274262)"}