[gdb/contrib] Handle DW_LANG_Mips_Assembler in dwarf-to-dwarf-assembler.py

I ran gdb/contrib/dwarf-to-dwarf-assembler.py on a hello world executable, and
ran into:
...
Traceback (most recent call last):
  File "dwarf-to-dwarf-assembler.py", line 654, in <module>
    main(sys.argv)
    ~~~~^^^^^^^^^^
  File "dwarf-to-dwarf-assembler.py", line 650, in main
    generator.generate()
    ~~~~~~~~~~~~~~~~~~^^
  File "dwarf-to-dwarf-assembler.py", line 622, in generate
    self.generate_die(die, indent_count)
    ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^
  File "dwarf-to-dwarf-assembler.py", line 601, in generate_die
    die_lines = die.format(self.dwarf_parser.offset_to_die, indent_count)
  File "dwarf-to-dwarf-assembler.py", line 291, in format
    return "\n".join(self.format_lines(offset_die_lookup, indent_count))
                     ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "dwarf-to-dwarf-assembler.py", line 388, in format_lines
    inner_lines = super().format_lines(offset_die_lookup, indent_count + 1)
  File "dwarf-to-dwarf-assembler.py", line 263, in format_lines
    attr_line = attr.format(
        offset_die_lookup, indent_count=indent_count + 1
    )
  File "dwarf-to-dwarf-assembler.py", line 209, in format
    s += "@" + LANG_NAME[self.value]
               ~~~~~~~~~^^^^^^^^^^^^
KeyError: 32769
...

The problem is that the language 0x8001 (DW_LANG_lo_user + 1) is not listed in
elftools.dwarf.enums.ENUM_DW_LANG.

This is MIPS vendor extension DW_LANG_MIPS_assembler, commonly used for
any assembly in DWARF versions that don't define a value for it (starting v6,
there's DW_LANG_Assembly).

Fix the generic case by emitting:
...
	    DW_AT_language 32769 DW_FORM_sdata
...
and this specific case by emitting:
...
	    DW_AT_language @DW_LANG_Mips_Assembler
...

Approved-By: Tom Tromey <tom@tromey.com>

diff --git a/gdb/contrib/dwarf-to-dwarf-assembler.py b/gdb/contrib/dwarf-to-dwarf-assembler.py
index 3efaf0dc85d827bb39fa34c8bea23c553c857dd9..ca4c76968353527f24f785893419ab539f86c1c6 100755 (executable)
--- a/gdb/contrib/dwarf-to-dwarf-assembler.py
+++ b/gdb/contrib/dwarf-to-dwarf-assembler.py
@@ -206,7 +206,13 @@ class DWARFAttribute:
         s += " "
 
         if self.name == "DW_AT_language" and isinstance(self.value, int):
-            s += "@" + LANG_NAME[self.value]
+            if LANG_NAME.get(self.value) is None:
+                if self.value == 0x8001:
+                    s += "@DW_LANG_Mips_Assembler"
+                else:
+                    s += str(self.value) + " DW_FORM_sdata"
+            else:
+                s += "@" + LANG_NAME[self.value]
         elif self.name == "DW_AT_encoding" and isinstance(self.value, int):
             s += "@" + ATE_NAME[self.value]
         else: