debug/programs/step.S

   1 // Test stepping over a variety of instructions.
   2
   3         .global main
   4
   5 main:
   6         la      t0, trap_entry          // 0, 4
   7         csrw    mtvec, t0               // 0x8
   8
   9         li      t0, 5                   // 0xc
  10         beq     zero, zero, one         // 0x10
  11         nop                             // 0x14
  12 one:
  13         beq     zero, t0, one           // 0x18
  14         // Use t0 instead of ra to force a 32-bit opcode in C mode. Otherwise
  15         // 32-bit and 64-bit binaries end up with different instructions (I
  16         // didn't pursue this).
  17         jal     t0, two                 // 0x1c
  18
  19 three:
  20         .word   0                       // 0x20
  21         nop                             // 0x24
  22
  23 two:
  24         jr      t0                      // 0x28
  25
  26         .align  2
  27 trap_entry:
  28         j       trap_entry              // 0x2c