How to disassemble a program using xobjdump

• version

  1.0.1

• scope

  Example.

  This code is provided as example code for a user to base their code on.

• description

  How to disassemble a program using xobjdump

• boards

  Unless otherwise specified, this example runs on the SliceKIT Core Board, but can easily be run on any XMOS device by using a different XN file.

The xTIMEcomposer tools contain the xobjdump utility, which you can use to disassemble a given executable. For example, compile the following code:

#include <print.h>

int main() {
  printstr("Hello World!\n");
  return 0;
}

From the command line, the resulting executable can be disassembled as follows:

xobjdump -d a.xe

This will produce the following output:

....
<main>:
             0x000100ac: 44 77:       entsp (u6)      0x4
             0x000100ae: 4e 68:       ldc (ru6)       r1, 0xe
             0x000100b0: 00 f0 05 60: ldaw (lru6)     r0, dp[0x5]
             0x000100b4: 00 f0 4d d0: bl (lu10)       0x4d <printstr>
             0x000100b8: 40 68:       ldc (ru6)       r1, 0x0
             0x000100ba: 42 54:       stw (ru6)       r1, sp[0x2]
             0x000100bc: 01 54:       stw (ru6)       r0, sp[0x1]
             0x000100be: 02 5c:       ldw (ru6)       r0, sp[0x2]
             0x000100c0: c4 77:       retsp (u6)      0x4
....

You can use xobjdump to intermix the source lines with the disassembly output. This is enabled via the -S command line option:

xobjdump -S a.xe

This will produce the following output:

....
int main() {
             0x000100ac: 44 77:       entsp (u6)      0x4
             0x000100ae: 4e 68:       ldc (ru6)       r1, 0xe
  printstr("Hello World!\n");
             0x000100b0: 00 f0 05 60: ldaw (lru6)     r0, dp[0x5]
             0x000100b4: 00 f0 4d d0: bl (lu10)       0x4d <printstr>
             0x000100b8: 40 68:       ldc (ru6)       r1, 0x0
  return 0;
             0x000100ba: 42 54:       stw (ru6)       r1, sp[0x2]
             0x000100bc: 01 54:       stw (ru6)       r0, sp[0x1]
             0x000100be: 02 5c:       ldw (ru6)       r0, sp[0x2]
             0x000100c0: c4 77:       retsp (u6)      0x4
....