[llvm] [llvm-dwarfdump] Support for DW_AT_language_name and DW_AT_language_version (PR #162449)

via llvm-commits llvm-commits at lists.llvm.org
Wed Oct 8 03:01:54 PDT 2025


llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-debuginfo

Author: Michael Buch (Michael137)

<details>
<summary>Changes</summary>

Depends on:
* https://github.com/llvm/llvm-project/pull/162434
* https://github.com/llvm/llvm-project/pull/162446

Makes sure we dump the attributes in a user-friendly way.

More info on the attributes here: https://dwarfstd.org/languages-v6.html

---
Full diff: https://github.com/llvm/llvm-project/pull/162449.diff


7 Files Affected:

- (modified) llvm/include/llvm/BinaryFormat/Dwarf.def (+3) 
- (modified) llvm/include/llvm/BinaryFormat/Dwarf.h (+2) 
- (modified) llvm/lib/BinaryFormat/Dwarf.cpp (+22) 
- (modified) llvm/lib/DebugInfo/DWARF/DWARFDie.cpp (+2-1) 
- (added) llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_name.s (+35) 
- (added) llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_version.s (+35) 
- (modified) llvm/unittests/BinaryFormat/DwarfTest.cpp (+35) 


``````````diff
diff --git a/llvm/include/llvm/BinaryFormat/Dwarf.def b/llvm/include/llvm/BinaryFormat/Dwarf.def
index 2c9a3c0f6fb04..fbf22cc6f760b 100644
--- a/llvm/include/llvm/BinaryFormat/Dwarf.def
+++ b/llvm/include/llvm/BinaryFormat/Dwarf.def
@@ -424,6 +424,9 @@ HANDLE_DW_AT(0x89, export_symbols, 5, DWARF)
 HANDLE_DW_AT(0x8a, deleted, 5, DWARF)
 HANDLE_DW_AT(0x8b, defaulted, 5, DWARF)
 HANDLE_DW_AT(0x8c, loclists_base, 5, DWARF)
+// New in Dwarf v6:
+HANDLE_DW_AT(0x90, language_name, 6, DWARF)
+HANDLE_DW_AT(0x91, language_version, 6, DWARF)
 
 // Vendor extensions:
 HANDLE_DW_AT(0x806, GHS_namespace_alias, 0, GHS)
diff --git a/llvm/include/llvm/BinaryFormat/Dwarf.h b/llvm/include/llvm/BinaryFormat/Dwarf.h
index 2c5012510a5c3..ba74ab9515a75 100644
--- a/llvm/include/llvm/BinaryFormat/Dwarf.h
+++ b/llvm/include/llvm/BinaryFormat/Dwarf.h
@@ -997,6 +997,7 @@ LLVM_ABI StringRef VisibilityString(unsigned Visibility);
 LLVM_ABI StringRef VirtualityString(unsigned Virtuality);
 LLVM_ABI StringRef EnumKindString(unsigned EnumKind);
 LLVM_ABI StringRef LanguageString(unsigned Language);
+LLVM_ABI StringRef SourceLanguageNameString(SourceLanguageName Lang);
 LLVM_ABI StringRef CaseString(unsigned Case);
 LLVM_ABI StringRef ConventionString(unsigned Convention);
 LLVM_ABI StringRef InlineCodeString(unsigned Code);
@@ -1038,6 +1039,7 @@ LLVM_ABI unsigned getSubOperationEncoding(unsigned OpEncoding,
 LLVM_ABI unsigned getVirtuality(StringRef VirtualityString);
 LLVM_ABI unsigned getEnumKind(StringRef EnumKindString);
 LLVM_ABI unsigned getLanguage(StringRef LanguageString);
+LLVM_ABI unsigned getSourceLanguageName(StringRef SourceLanguageNameString);
 LLVM_ABI unsigned getCallingConvention(StringRef LanguageString);
 LLVM_ABI unsigned getAttributeEncoding(StringRef EncodingString);
 LLVM_ABI unsigned getMacinfo(StringRef MacinfoString);
diff --git a/llvm/lib/BinaryFormat/Dwarf.cpp b/llvm/lib/BinaryFormat/Dwarf.cpp
index 8b24044e19e50..033c6a44be638 100644
--- a/llvm/lib/BinaryFormat/Dwarf.cpp
+++ b/llvm/lib/BinaryFormat/Dwarf.cpp
@@ -472,6 +472,26 @@ StringRef llvm::dwarf::LanguageDescription(dwarf::SourceLanguageName lname) {
   return "Unknown";
 }
 
+llvm::StringRef llvm::dwarf::SourceLanguageNameString(SourceLanguageName Lang) {
+  switch (Lang) {
+#define HANDLE_DW_LNAME(ID, NAME, DESC, LOWER_BOUND)                           \
+  case DW_LNAME_##NAME:                                                        \
+    return "DW_LNAME_" #NAME;
+#include "llvm/BinaryFormat/Dwarf.def"
+  }
+
+  return {};
+}
+
+unsigned
+llvm::dwarf::getSourceLanguageName(StringRef SourceLanguageNameString) {
+  return StringSwitch<unsigned>(SourceLanguageNameString)
+#define HANDLE_DW_LNAME(ID, NAME, DESC, LOWER_BOUND)                           \
+  .Case("DW_LNAME_" #NAME, DW_LNAME_##NAME)
+#include "llvm/BinaryFormat/Dwarf.def"
+      .Default(0);
+}
+
 StringRef llvm::dwarf::CaseString(unsigned Case) {
   switch (Case) {
   case DW_ID_case_sensitive:
@@ -762,6 +782,8 @@ StringRef llvm::dwarf::AttributeValueString(uint16_t Attr, unsigned Val) {
     return DefaultedMemberString(Val);
   case DW_AT_APPLE_enum_kind:
     return EnumKindString(Val);
+  case DW_AT_language_name:
+    return SourceLanguageNameString(static_cast<SourceLanguageName>(Val));
   }
 
   return StringRef();
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
index edc69a36cdff2..212a0c039298b 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
@@ -149,7 +149,8 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
   if (!Name.empty())
     WithColor(OS, Color) << Name;
   else if (Attr == DW_AT_decl_line || Attr == DW_AT_decl_column ||
-           Attr == DW_AT_call_line || Attr == DW_AT_call_column) {
+           Attr == DW_AT_call_line || Attr == DW_AT_call_column ||
+           Attr == DW_AT_language_version) {
     if (std::optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
       OS << *Val;
     else
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_name.s b/llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_name.s
new file mode 100644
index 0000000000000..af581753be56a
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_name.s
@@ -0,0 +1,35 @@
+# Demonstrate dumping DW_AT_language_name.
+# RUN: llvm-mc -triple=x86_64--linux -filetype=obj < %s | \
+# RUN:     llvm-dwarfdump -v - | FileCheck %s
+
+# CHECK: .debug_abbrev contents:
+# CHECK: DW_AT_language_name DW_FORM_data2
+# CHECK: DW_AT_language_name DW_FORM_data2
+# CHECK: .debug_info contents:
+# CHECK: DW_AT_language_name [DW_FORM_data2] (DW_LNAME_C)
+# CHECK: DW_AT_language_name [DW_FORM_data2] (0x0000)
+
+        .section        .debug_abbrev,"", at progbits
+        .byte   1                       # Abbreviation Code
+        .byte   17                      # DW_TAG_compile_unit
+        .byte   1                       # DW_CHILDREN_no 
+        .ascii  "\220\001"              # DW_AT_language_name
+        .byte   5                       # DW_FORM_data2
+        .ascii  "\220\001"              # DW_AT_language_name
+        .byte   5                       # DW_FORM_data2
+        .byte   0                       # EOM(1)
+        .byte   0                       # EOM(2)
+        .byte   0                       # EOM(3)
+
+        .section        .debug_info,"", at progbits
+        .long   .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
+.Ldebug_info_start0:
+        .short  5                       # DWARF version number
+        .byte   1                       # Unit type
+        .byte   8                       # Address Size (in bytes)
+        .long   .debug_abbrev           # Offset Into Abbrev. Section
+        .byte   1                       # Abbrev [1] DW_TAG_compile_unit
+        .short  3                       # DW_AT_language_name
+        .short  0                       # DW_AT_language_name
+        .byte   0 
+.Ldebug_info_end0:
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_version.s b/llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_version.s
new file mode 100644
index 0000000000000..f1be8fdf6cd3e
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/DW_AT_language_version.s
@@ -0,0 +1,35 @@
+# Demonstrate dumping DW_AT_language_version.
+# RUN: llvm-mc -triple=x86_64--linux -filetype=obj < %s | \
+# RUN:     llvm-dwarfdump -v - | FileCheck %s
+
+# CHECK: .debug_abbrev contents:
+# CHECK: DW_AT_language_version DW_FORM_data4
+# CHECK: DW_AT_language_version DW_FORM_data2
+# CHECK: .debug_info contents:
+# CHECK: DW_AT_language_version [DW_FORM_data4] (201402)
+# CHECK: DW_AT_language_version [DW_FORM_data2] (0)
+
+        .section        .debug_abbrev,"", at progbits
+        .byte   1                       # Abbreviation Code
+        .byte   17                      # DW_TAG_compile_unit
+        .byte   1                       # DW_CHILDREN_no 
+        .ascii  "\221\001"              # DW_AT_language_version
+        .byte   6                       # DW_FORM_data4
+        .ascii  "\221\001"              # DW_AT_language_version
+        .byte   5                       # DW_FORM_data2
+        .byte   0                       # EOM(1)
+        .byte   0                       # EOM(2)
+        .byte   0                       # EOM(3)
+
+        .section        .debug_info,"", at progbits
+        .long   .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
+.Ldebug_info_start0:
+        .short  5                       # DWARF version number
+        .byte   1                       # Unit type
+        .byte   8                       # Address Size (in bytes)
+        .long   .debug_abbrev           # Offset Into Abbrev. Section
+        .byte   1                       # Abbrev [1] DW_TAG_compile_unit
+        .long   201402                  # DW_AT_language_version
+        .short  0                       # DW_AT_language_version
+        .byte   0 
+.Ldebug_info_end0:
diff --git a/llvm/unittests/BinaryFormat/DwarfTest.cpp b/llvm/unittests/BinaryFormat/DwarfTest.cpp
index 684e59fa2785c..1162eb709aa83 100644
--- a/llvm/unittests/BinaryFormat/DwarfTest.cpp
+++ b/llvm/unittests/BinaryFormat/DwarfTest.cpp
@@ -219,4 +219,39 @@ TEST(DwarfTest, lname) {
   EXPECT_EQ(roundtrip(DW_LANG_##NAME), DW_LANG_##NAME);
 #include "llvm/BinaryFormat/Dwarf.def"
 }
+
+TEST(DwarfTest, lname_getSourceLanguageName) {
+  // Some basics.
+  EXPECT_EQ(getSourceLanguageName("DW_LNAME_Ada"), DW_LNAME_Ada);
+  EXPECT_EQ(getSourceLanguageName("DW_LNAME_Metal"), DW_LNAME_Metal);
+
+  // Test invalid input.
+  EXPECT_EQ(getSourceLanguageName(""), 0U);
+  EXPECT_EQ(getSourceLanguageName("blah"), 0U);
+  EXPECT_EQ(getSourceLanguageName("DW_LNAME__something_unlikely"), 0U);
+  EXPECT_EQ(getSourceLanguageName("DW_LANG_C"), 0U);
+
+  // Test that we cover all DW_LNAME_ names.
+#define xstr(X) #X
+#define HANDLE_DW_LNAME(ID, NAME, DESC, LOWER_BOUND)                           \
+  EXPECT_EQ(getSourceLanguageName(xstr(DW_LNAME_##NAME)), DW_LNAME_##NAME);
+#include "llvm/BinaryFormat/Dwarf.def"
+}
+
+TEST(DwarfTest, lname_SourceLanguageNameString) {
+  // Some basics.
+  EXPECT_EQ(SourceLanguageNameString(DW_LNAME_C_plus_plus),
+            "DW_LNAME_C_plus_plus");
+  EXPECT_EQ(SourceLanguageNameString(DW_LNAME_CPP_for_OpenCL),
+            "DW_LNAME_CPP_for_OpenCL");
+
+  // Test invalid input.
+  EXPECT_EQ(SourceLanguageNameString(static_cast<SourceLanguageName>(0)), "");
+
+  // Test that we cover all DW_LNAME_ names.
+#define xstr(X) #X
+#define HANDLE_DW_LNAME(ID, NAME, DESC, LOWER_BOUND)                           \
+  EXPECT_EQ(SourceLanguageNameString(DW_LNAME_##NAME), xstr(DW_LNAME_##NAME));
+#include "llvm/BinaryFormat/Dwarf.def"
+}
 } // end namespace

``````````

</details>


https://github.com/llvm/llvm-project/pull/162449


More information about the llvm-commits mailing list