[ dwarfdump ] Add symbolic dump of known DWARF attribute values.

[dblaikie]

lib/DebugInfo/DWARFDebugInfoEntry.cpp

90 ↗

(On Diff #13248)

Roll the "Val" variable into the if condition to reduce its scope:

if (Optional<uint64_t> Val = formValue.getAsUnsignedConstant())

Name = AttributeValueString(attr, Val.getValue());

(personally I prefer using the pointer-like interface of Optional (so I would write "*Val" rather than "Val.getValue()") but opinions differ and there's no solid convention in the codebase so far - so do whichever you prefer, I just mention it in case you aren't aware of it)

96 ↗

(On Diff #13248)

Mistaken indentation here? (looks like a 4 space instead of a 2, but it might be the review software being weird)

lib/Support/Dwarf.cpp

799 ↗

(On Diff #13248)

As a follow-up, if you like, all these functions should /probably/ be modified to return StringRef, that way we don't have to compute their length later on (or do null-test walks) in printing functions, etc.

799 ↗

(On Diff #13248)

Should the type of Attr be something more type-safe? (the actual enum of DWARF attributes)

829 ↗

(On Diff #13248)

This line is unreachable (so far as I can see?) and should be deleted.

(alternatively you could leave this one and remove the default case from the switch)

[friss]

lib/DebugInfo/DWARFDebugInfoEntry.cpp

90 ↗

(On Diff #13248)

Will do. I wasn't aware of Optional::operator*. I'll use it.

96 ↗

(On Diff #13248)

No the indentation is really off.

lib/Support/Dwarf.cpp

799 ↗

(On Diff #13248)

I first wrote it like that, but I was finding the cast at the call site awkward. I can add it back, but we have no guarantee that the data we've read from the DWARF file will actually be a known Attribute, thus I find it more accurate to allow all values.

829 ↗

(On Diff #13248)

I actually wondered while writing the code if all supported compilers could correctly do the control flow analysis that proves that the second return is unnecessary. I added the default case to prevent warnings about missed cases when I was using a typed enum Attr, but now the default case can just go away.

[dblaikie]

Looks good with your responses (& implied/pending updates) to the last round of comments, please commit once you've made those changes.

lib/Support/Dwarf.cpp

799 ↗

(On Diff #13248)

Fair enough.

[friss]

Closed by commit rL217186 (authored by @friss).

llvm/trunk/include/llvm/Support/Dwarf.h

private:
   enum {
     KIND_OFFSET = 4,
     KIND_MASK = 7 << KIND_OFFSET,
     LINKAGE_OFFSET = 7,
     LINKAGE_MASK = 1 << LINKAGE_OFFSET
   };
 };
 
+/// Returns the symbolic string representing Val when used as a value
+/// for attribute Attr.
+const char *AttributeValueString(uint16_t Attr, unsigned Val);
+
 } // End of namespace dwarf
 
 } // End of namespace llvm
 
 #endif

llvm/trunk/lib/DebugInfo/DWARFDebugInfoEntry.cpp

else
     OS << format(" [DW_FORM_Unknown_%x]", form);
 
   DWARFFormValue formValue(form);
 
   if (!formValue.extractValue(u->getDebugInfoExtractor(), offset_ptr, u))
     return;
 
   OS << "\t(";
+  
+  const char *Name = nullptr;
+  if (Optional<uint64_t> Val = formValue.getAsUnsignedConstant())
+    Name = AttributeValueString(attr, *Val);
+
+  if (Name) {
+    OS << Name;
+  } else {
     formValue.dump(OS, u);
+  }
+
   OS << ")\n";
 }
 
 bool DWARFDebugInfoEntryMinimal::extractFast(const DWARFUnit *U,
                                              uint32_t *OffsetPtr) {
   Offset = *OffsetPtr;
   DataExtractor DebugInfoData = U->getDebugInfoExtractor();
   uint32_t UEndOffset = U->getNextUnitOffset();

llvm/trunk/lib/Support/Dwarf.cpp

const char *llvm::dwarf::GDBIndexEntryLinkageString(GDBIndexEntryLinkage Linkage) {
   switch (Linkage) {
   case GIEL_EXTERNAL:
     return "EXTERNAL";
   case GIEL_STATIC:
     return "STATIC";
   }
   llvm_unreachable("Unknown GDBIndexEntryLinkage value");
 }
+
+const char *llvm::dwarf::AttributeValueString(uint16_t Attr, unsigned Val) {
+  switch (Attr) {
+  case DW_AT_accessibility:
+    return AccessibilityString(Val);
+  case DW_AT_virtuality:
+    return VirtualityString(Val);
+  case DW_AT_language:
+    return LanguageString(Val);
+  case DW_AT_encoding:
+    return AttributeEncodingString(Val);
+  case DW_AT_decimal_sign:
+    return DecimalSignString(Val);
+  case DW_AT_endianity:
+    return EndianityString(Val);
+  case DW_AT_visibility:
+    return VisibilityString(Val);
+  case DW_AT_identifier_case:
+    return CaseString(Val);
+  case DW_AT_calling_convention:
+    return ConventionString(Val);
+  case DW_AT_inline:
+    return InlineCodeString(Val);
+  case DW_AT_ordering:
+    return ArrayOrderString(Val);
+  case DW_AT_discr_value:
+    return DiscriminantString(Val);
+  }
+
+  return nullptr;
+}

llvm/trunk/test/DebugInfo/X86/debug-info-access.ll

 ;
 ; CHECK: DW_TAG_subprogram
 ; CHECK:     DW_AT_name {{.*}}"pub_default")
 ; CHECK-NOT: DW_AT_accessibility
 ; CHECK: DW_TAG
 ;
 ; CHECK: DW_TAG_inheritance
 ; CHECK-NOT: DW_TAG
-; CHECK:     DW_AT_accessibility {{.*}}(0x01)
+; CHECK:     DW_AT_accessibility {{.*}}(DW_ACCESS_public)
 ;
 ; CHECK: DW_TAG_member
 ; CHECK:     DW_AT_name {{.*}}"public_static")
 ; CHECK-NOT: DW_TAG
-; CHECK:     DW_AT_accessibility {{.*}}(0x01)
+; CHECK:     DW_AT_accessibility {{.*}}(DW_ACCESS_public)
 ;
 ; CHECK: DW_TAG_subprogram
 ; CHECK:     DW_AT_name {{.*}}"pub")
 ; CHECK-NOT: DW_TAG
-; CHECK:     DW_AT_accessibility {{.*}}(0x01)
+; CHECK:     DW_AT_accessibility {{.*}}(DW_ACCESS_public)
 ;
 ; CHECK: DW_TAG_subprogram
 ; CHECK:     DW_AT_name {{.*}}"prot")
 ; CHECK-NOT: DW_TAG
-; CHECK:     DW_AT_accessibility {{.*}}(0x02)
+; CHECK:     DW_AT_accessibility {{.*}}(DW_ACCESS_protected)
 ;
 ; CHECK: DW_TAG_subprogram
 ; CHECK:     DW_AT_name {{.*}}"priv_default")
 ; CHECK-NOT: DW_AT_accessibility
 ; CHECK: DW_TAG
 ;
 ; CHECK: DW_TAG_member
 ; CHECK:     DW_AT_name {{.*}}"union_priv")
 ; CHECK-NOT: DW_TAG
-; CHECK:     DW_AT_accessibility {{.*}}(0x03)
+; CHECK:     DW_AT_accessibility {{.*}}(DW_ACCESS_private)
 ;
 ; CHECK: DW_TAG_subprogram
 ; CHECK:     DW_AT_name {{.*}}"union_pub_default")
 ; CHECK-NOT: DW_AT_accessibility
 ; CHECK: DW_TAG
 ;
 ; CHECK: DW_TAG_subprogram
 ; CHECK:     DW_AT_name {{.*}}"free")

llvm/trunk/test/DebugInfo/X86/debug-info-static-member.ll

 ;
 ; PRESENT:      .debug_info contents:
 ; PRESENT:      DW_TAG_class_type
 ; PRESENT-NEXT: DW_AT_name {{.*}} "C"
 ; PRESENT:      0x[[DECL_A:[0-9a-f]+]]: DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "a"
 ; PRESENT:      DW_AT_external
 ; PRESENT:      DW_AT_declaration
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x03)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_private)
 ; PRESENT:      DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "const_a"
 ; PRESENT:      DW_AT_external
 ; PRESENT:      DW_AT_declaration
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x03)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_private)
 ; PRESENT:      DW_AT_const_value {{.*}} (1)
 ; PRESENT:      0x[[DECL_B:[0-9a-f]+]]: DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "b"
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x02)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_protected)
 ; PRESENT:      DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "const_b"
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x02)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_protected)
 ; PRESENT:      DW_AT_const_value [DW_FORM_udata] (1078523331)
 ; PRESENT:      0x[[DECL_C:[0-9a-f]+]]: DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "c"
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; PRESENT:      DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "const_c"
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; PRESENT:      DW_AT_const_value {{.*}} (18)
 ; While we're here, a normal member has data_member_location and
 ; accessibility attributes.
 ; PRESENT:      DW_TAG_member
 ; PRESENT-NEXT: DW_AT_name {{.*}} "d"
 ; PRESENT:      DW_AT_data_member_location
-; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; PRESENT:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; PRESENT:      NULL
 ; Definitions point back to their declarations, and have a location.
 ; PRESENT:      DW_TAG_variable
 ; PRESENT-NEXT: DW_AT_specification {{.*}} {0x[[DECL_A]]}
 ; PRESENT-NEXT: DW_AT_location
 ; PRESENT-NEXT: DW_AT_linkage_name {{.*}} "_ZN1C1aE"
 ; PRESENT:      DW_TAG_variable
 ; PRESENT-NEXT: DW_AT_specification {{.*}} {0x[[DECL_B]]}
 ; PRESENT-NEXT: DW_AT_location
 ; PRESENT-NEXT: DW_AT_linkage_name {{.*}} "_ZN1C1bE"
 ; PRESENT:      DW_TAG_variable
 ; PRESENT-NEXT: DW_AT_specification {{.*}} {0x[[DECL_C]]}
 ; PRESENT-NEXT: DW_AT_location
 ; PRESENT-NEXT: DW_AT_linkage_name {{.*}} "_ZN1C1cE"
 
 ; For Darwin gdb:
 ; DARWINP:      .debug_info contents:
 ; DARWINP:      DW_TAG_class_type
 ; DARWINP-NEXT: DW_AT_name {{.*}} "C"
 ; DARWINP:      0x[[DECL_A:[0-9a-f]+]]: DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "a"
 ; DARWINP:      DW_AT_external
 ; DARWINP:      DW_AT_declaration
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x03)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_private)
 ; DARWINP:      DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "const_a"
 ; DARWINP:      DW_AT_external
 ; DARWINP:      DW_AT_declaration
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x03)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_private)
 ; DARWINP:      DW_AT_const_value {{.*}} (1)
 ; DARWINP:      0x[[DECL_B:[0-9a-f]+]]: DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "b"
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x02)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_protected)
 ; DARWINP:      DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "const_b"
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x02)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_protected)
 ; DARWINP:      DW_AT_const_value [DW_FORM_udata] (1078523331)
 ; DARWINP:      0x[[DECL_C:[0-9a-f]+]]: DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "c"
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; DARWINP:      DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "const_c"
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; DARWINP:      DW_AT_const_value {{.*}} (18)
 ; While we're here, a normal member has data_member_location and
 ; accessibility attributes.
 ; DARWINP:      DW_TAG_member
 ; DARWINP-NEXT: DW_AT_name {{.*}} "d"
 ; DARWINP:      DW_AT_data_member_location
-; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; DARWINP:      DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; DARWINP:      NULL
 ; Definitions point back to their declarations, and have a location.
 ; DARWINP:      DW_TAG_variable
 ; DARWINP-NEXT: DW_AT_specification {{.*}} {0x[[DECL_A]]}
 ; DARWINP-NEXT: DW_AT_location
 ; DARWINP-NEXT: DW_AT_linkage_name {{.*}} "_ZN1C1aE"
 ; DARWINP:      DW_TAG_variable
 ; DARWINP-NEXT: DW_AT_specification {{.*}} {0x[[DECL_B]]}

llvm/trunk/test/DebugInfo/X86/empty-and-one-elem-array.ll

 
 declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
 
 ; An empty array should not have an AT_upper_bound attribute. But an array of 1
 ; should.
 
 ; CHECK:      DW_TAG_base_type
 ; CHECK-NEXT: DW_AT_name [DW_FORM_strp]  ( .debug_str[{{.*}}] = "int")
-; CHECK-NEXT: DW_AT_encoding [DW_FORM_data1]   (0x05)
+; CHECK-NEXT: DW_AT_encoding [DW_FORM_data1]   (DW_ATE_signed)
 ; CHECK-NEXT: DW_AT_byte_size [DW_FORM_data1]  (0x04)
 
 ; int foo::b[1]:
 ; CHECK: DW_TAG_structure_type
 ; CHECK: DW_AT_name{{.*}}"foo"
 ; CHECK:      DW_TAG_member
 ; CHECK:      DW_TAG_member
 ; CHECK-NEXT: DW_AT_name [DW_FORM_strp]  ( .debug_str[{{.*}}] = "b")

llvm/trunk/test/DebugInfo/X86/empty-array.ll

 ; CHECK:      DW_TAG_subrange_type
 ; CHECK-NEXT: DW_AT_type [DW_FORM_ref4]  (cu + 0x{{[0-9a-f]*}} => {[[BASE2:0x[0-9a-f]*]]})
 ; CHECK-NOT:  DW_AT_upper_bound
 
 ; CHECK: [[BASETYPE]]: DW_TAG_base_type
 ; CHECK: [[BASE2]]: DW_TAG_base_type
 ; CHECK-NEXT: DW_AT_name
 ; CHECK-NEXT: DW_AT_byte_size [DW_FORM_data1]  (0x08)
-; CHECK-NEXT: DW_AT_encoding [DW_FORM_data1]   (0x07)
+; CHECK-NEXT: DW_AT_encoding [DW_FORM_data1]   (DW_ATE_unsigned)
 
 !llvm.dbg.cu = !{!0}
 !llvm.module.flags = !{!21}
 
 !0 = metadata !{i32 786449, metadata !20, i32 4, metadata !"clang version 3.3 (trunk 169136)", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !1, metadata !3,  metadata !1, metadata !""} ; [ DW_TAG_compile_unit ] [/Volumes/Sandbox/llvm/t.cpp] [DW_LANG_C_plus_plus]
 !1 = metadata !{}
 !3 = metadata !{metadata !5}
 !5 = metadata !{i32 786484, i32 0, null, metadata !"a", metadata !"a", metadata !"", metadata !6, i32 1, metadata !7, i32 0, i32 1, %class.A* @a, null} ; [ DW_TAG_variable ] [a] [line 1] [def]

llvm/trunk/test/DebugInfo/X86/fission-cu.ll

 ; CHECK-NEXT: DW_AT_GNU_dwo_name [DW_FORM_strp] ( .debug_str[0x00000000] = "baz.dwo")
 ; CHECK-NEXT: DW_AT_comp_dir [DW_FORM_strp]     ( .debug_str[0x00000008] = "/usr/local/google/home/echristo/tmp")
 ; CHECK-NEXT: DW_AT_GNU_dwo_id [DW_FORM_data8]  (0x1f1f859683d49324)
 
 ; Check that the rest of the compile units have information.
 ; CHECK: .debug_info.dwo contents:
 ; CHECK: DW_TAG_compile_unit
 ; CHECK: DW_AT_producer [DW_FORM_GNU_str_index] ( indexed (00000000) string = "clang version 3.3 (trunk 169021) (llvm/trunk 169020)")
-; CHECK: DW_AT_language [DW_FORM_data2]        (0x000c)
+; CHECK: DW_AT_language [DW_FORM_data2]        (DW_LANG_C99)
 ; CHECK: DW_AT_name [DW_FORM_GNU_str_index]    ( indexed (00000001) string = "baz.c")
 ; CHECK-NOT: DW_AT_low_pc
 ; CHECK-NOT: DW_AT_stmt_list
 ; CHECK-NOT: DW_AT_comp_dir
 ; CHECK: DW_AT_GNU_dwo_id [DW_FORM_data8]  (0x1f1f859683d49324)
 ; CHECK: DW_TAG_variable
 ; CHECK: DW_AT_name [DW_FORM_GNU_str_index]     ( indexed (00000002) string = "a")
 ; CHECK: DW_AT_type [DW_FORM_ref4]       (cu + 0x{{[0-9a-f]*}} => {[[TYPE:0x[0-9a-f]*]]})

llvm/trunk/test/DebugInfo/X86/nondefault-subrange-array.ll

 ; CHECK-NEXT:                   DW_AT_type [DW_FORM_ref4]  (cu + 0x{{[0-9a-f]*}} => {[[BASE2:0x[0-9a-f]*]]})
 ; CHECK-NEXT:                   DW_AT_lower_bound [DW_FORM_data8]       (0xfffffffffffffffd)
 ; CHECK-NEXT:                   DW_AT_upper_bound [DW_FORM_data1]       (0x26)
 
 ; CHECK: [[BASE]]: DW_TAG_base_type
 ; CHECK: [[BASE2]]: DW_TAG_base_type
 ; CHECK-NEXT:                 DW_AT_name [DW_FORM_strp]       ( .debug_str[0x{{[0-9a-f]*}}] = "sizetype")
 ; CHECK-NEXT:                 DW_AT_byte_size [DW_FORM_data1] (0x08)
-; CHECK-NEXT:                 DW_AT_encoding [DW_FORM_data1]  (0x07)
+; CHECK-NEXT:                 DW_AT_encoding [DW_FORM_data1]  (DW_ATE_unsigned)
 
 !llvm.dbg.cu = !{!0}
 !llvm.module.flags = !{!21}
 
 !0 = metadata !{i32 786449, metadata !20, i32 4, metadata !"clang version 3.3 (trunk 169136)", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !1, metadata !3,  metadata !1, metadata !""} ; [ DW_TAG_compile_unit ] [/Volumes/Sandbox/llvm/t.cpp] [DW_LANG_C_plus_plus]
 !1 = metadata !{}
 !3 = metadata !{metadata !5}
 !5 = metadata !{i32 786484, i32 0, null, metadata !"a", metadata !"a", metadata !"", metadata !6, i32 1, metadata !7, i32 0, i32 1, %class.A* @a, null} ; [ DW_TAG_variable ] [a] [line 1] [def]

llvm/trunk/test/Linker/type-unique-simple2-a.ll

 ;
 ; $ cat a.cpp
 ; #include "ab.h"
 ; foo_t bar() {
 ;     return A().getFoo();
 ; }
 ;
 ; CHECK: _ZN1A6setFooEv
-; CHECK: DW_AT_accessibility [DW_FORM_data1]   (0x01)
+; CHECK: DW_AT_accessibility [DW_FORM_data1]   (DW_ACCESS_public)
 ; CHECK-NOT: DW_AT_accessibility
 ; CHECK: DW_TAG
 
 ; ModuleID = 'a.cpp'
 
 %class.A = type { i32 (...)** }
 
 @_ZTV1A = external unnamed_addr constant [4 x i8*]