Syntax highlighting for objdump output

Question

Currently I am working a lot with objdump output (arm / thumb instructions):

The command (arm-none-eabi-objdump -h -S main.elf > main.lst) creates a mixture of assembly (with addresses and hex representations) and c-code. Like this:

080009e4 <configure_led1>:

// configure ccu4 of led1
void configure_led1(uint16_t off_time, uint16_t on_time){
 80009e4:       b480            push    {r7}
 80009e6:       b085            sub     sp, #20
 80009e8:       af00            add     r7, sp, #0
 80009ea:       4603            mov     r3, r0
 80009ec:       460a            mov     r2, r1

Unfortunately the syntax highlighting of vim gets confused by this file. It uses assembly syntax highlighting for the file (:set filetype? returns asm). This syntax doesn't work well with the instruction addresses and hex representations in front of the actual assembly instructions.

How do I need to configure vim to use correct highlighting? Does vim have a specific filetype for objdump output?

Answer 1

This is rather meant as a demonstration, not a full-featured syntax file. But it should work correctly against an example above (except only few assemblers, such as GNU, support C/C++ comments natively; in general such comments should be marked as C syntax region).

~/.vim/syntax/objdump.vim

" standard guard against syntax clash
if exists("b:current_syntax")
    finish
endif

" Asm is our main syntax; C is an extra one
runtime! syntax/asm.vim
unlet b:current_syntax
syntax include @C syntax/c.vim
unlet b:current_syntax

" a line starting with [A-Za-z_] is a C line
syntax region odCLine start=/^\h/ end=/$/ keepend contains=@C

" a line starting with a hex number is an objdump address/opcode
" stop at [:xdigit:][:blank:][:blank:] to interpret the rest as asm instruction (default)
syntax region odHead start='^\s*\x\+\>' end=/\x\s\{2,}\|$/ keepend contains=odHex,asmIdentifier

" hex number w/o any prefix (deadbeef)
syntax match odHex '\<\x\+\>' contained
hi def link odHex hexNumber

" assign current syntax
let b:current_syntax = 'objdump'

Of course, you still need filetype/ftdetect to make it working.