CCS/TMS320F28375D: ofd2000 results - meaning of "code" under abbreviations table

Lenio Cacula

Part Number: TMS320F28375D

Tool/software: Code Composer Studio

In the abbreviations table of the file generated by ofd2000 -g, one of the columns is named "code". What does it mean?

DWARF Abbreviations Tables in Section 132 (".debug_abbrev")

    --------------------------------------
    Abbreviations Table at Offset 0x0
    --------------------------------------

    offset   code child tag/attribute                 form            
    -------- ---- ----- -------------                 ----            
    0x0         1 yes   DW_TAG_array_type                             
    0x3                    DW_AT_sibling              DW_FORM_ref_addr
    0x5                    DW_AT_byte_size            DW_FORM_data2   
    0x7                    DW_AT_language             DW_FORM_data1   
    0x9                    DW_AT_type                 DW_FORM_ref_addr
    0xd         2 yes   DW_TAG_array_type                             
    0x10                   DW_AT_sibling              DW_FORM_ref_addr
    0x12                   DW_AT_byte_size            DW_FORM_data1   
    0x14                   DW_AT_language             DW_FORM_data1   
    0x16                   DW_AT_type                 DW_FORM_ref_addr
    0x1a        3 no    DW_TAG_formal_parameter                       
    0x1d                   DW_AT_location             DW_FORM_block1  
    0x1f                   DW_AT_name                 DW_FORM_string  
    0x21                   DW_AT_type                 DW_FORM_ref_addr
    0x23                   DW_AT_TI_symbol_name       DW_FORM_string  
    0x28        4 no    DW_TAG_formal_parameter                       
    0x2b                   DW_AT_type                 DW_FORM_ref_addr
    0x2f        5 yes   DW_TAG_lexical_block                          
    0x32                   DW_AT_sibling              DW_FORM_ref_addr
    0x34                   DW_AT_low_pc               DW_FORM_addr    
    0x36                   DW_AT_high_pc              DW_FORM_addr

over 5 years ago

0 Zachary Morgan over 5 years ago

TI__Intellectual 885 points

Hi Lenio,

The "code" column corresponds to the "abbreviation code" referred to in 7.5.3 of the DWARF 4 standard, which can be referenced at http://dwarfstd.org/doc/DWARF4.pdf. This value corresponds to the abbreviation code listed on a Debugging Information Entry in the debug_info section. For example, in a simple program, the debug_info section may contain:

...
    000000d2   4    DW_TAG_unspecified_type
    000000d3           DW_AT_name void
    000000d8   2    DW_TAG_base_type
    000000d9           DW_AT_name      bool
    000000de           DW_AT_byte_size 1
    000000df           DW_AT_encoding  DW_ATE_boolean
    000000e0   2    DW_TAG_base_type
    000000e1           DW_AT_name      signed char
    000000ed           DW_AT_byte_size 1
    000000ee           DW_AT_encoding  DW_ATE_signed_char
    000000ef   2    DW_TAG_base_type
    000000f0           DW_AT_name      unsigned char
    000000fe           DW_AT_byte_size 1
    000000ff           DW_AT_encoding  DW_ATE_unsigned_char
...

And the debug_info section may contain:

    offset   code child tag/attribute              form
    -------- ---- ----- -------------              ----
    0x0         1 yes   DW_TAG_compile_unit
    0x3                    DW_AT_name              DW_FORM_string
    0x5                    DW_AT_stmt_list         DW_FORM_data4
    0x7                    DW_AT_language          DW_FORM_data1
    0x9                    DW_AT_comp_dir          DW_FORM_string
    0xb                    DW_AT_producer          DW_FORM_string
    0xd                    DW_AT_TI_version        DW_FORM_data1
    0x12        2 no    DW_TAG_base_type
    0x15                   DW_AT_name              DW_FORM_string
    0x17                   DW_AT_byte_size         DW_FORM_data1
    0x19                   DW_AT_encoding          DW_FORM_data1
    0x1d        3 yes   DW_TAG_subprogram
    0x20                   DW_AT_sibling           DW_FORM_ref_addr
    0x22                   DW_AT_name              DW_FORM_string
    0x24                   DW_AT_low_pc            DW_FORM_addr
    0x26                   DW_AT_high_pc           DW_FORM_addr
    0x28                   DW_AT_external          DW_FORM_flag
    0x2a                   DW_AT_type              DW_FORM_ref_addr
    0x2c                   DW_AT_TI_symbol_name    DW_FORM_string
    0x2f                   DW_AT_TI_begin_file     DW_FORM_string
    0x32                   DW_AT_TI_begin_line     DW_FORM_data1
    0x35                   DW_AT_TI_begin_column   DW_FORM_data1
    0x38                   DW_AT_TI_end_file       DW_FORM_string
    0x3b                   DW_AT_TI_end_line       DW_FORM_data1
    0x3e                   DW_AT_TI_end_column     DW_FORM_data1
    0x41                   DW_AT_TI_max_frame_size DW_FORM_sdata
    0x46        4 no    DW_TAG_unspecified_type
    0x49                   DW_AT_name              DW_FORM_string
...

In this case, the abbrev code 4 is used once and the abbrev code 2 is used 3 times in this portion of the output. The debug_abbrev section is providing the structure of the information and the debug_info section is providing the values.

Code Composer Studio™︎

Code Composer Studio forum

CCS/TMS320F28375D: ofd2000 results - meaning of "code" under abbreviations table