isa6

Download: isa6.zip

This code uses stw and ldw instructions, referenced to the stack or frame pointer. The stack pointer is set explicity and then copied to the frame pointer. This means that there are no references to memory other than through the stack.

Contents

.include "./nios_macros.m"

.text

.global main
.type main, @function

main:
    movi    sp,0xffc
    addi    sp,sp,-64
    stw    ra,60(sp)
    stw    fp,56(sp)
    mov    fp,sp
    movi    r4,24
    stw    r4,8(fp)
    movi    r4,19
    stw    r4,4(fp)
    ldw    r3,8(fp)
    ldw    r5,4(fp)
    add    r4,r3,r5
    stw    r4,0(fp)
    ldw    fp,56(sp)
end:
    br    end   /* wait here once the program has completed */
.end

#!/bin/sh
nios2-elf-gcc isa6.s
nios2-elf-size a.out > isa6.size.txt
nios2-elf-objdump -dS a.out > isa6.disassemble.txt
nios2-elf-objdump -h a.out > isa6.headers.txt
nios2-elf-nm a.out > isa6.symbols.txt
nios2-elf-objcopy -S -O binary a.out isa6.bin
nios2-iss -td:sim6.txt --trace-from=main -f a.out

   text       data        bss        dec        hex    filename
    622        896          0       1518        5ee    a.out

00000030 <main>:
  30:    06c3ff04     movi    sp,4092
  34:    defff004     addi    sp,sp,-64
  38:    dfc00f15     stw    ra,60(sp)
  3c:    df000e15     stw    fp,56(sp)
  40:    d839883a     mov    fp,sp
  44:    01000604     movi    r4,24
  48:    e1000215     stw    r4,8(fp)
  4c:    010004c4     movi    r4,19
  50:    e1000115     stw    r4,4(fp)
  54:    e0c00217     ldw    r3,8(fp)
  58:    e1400117     ldw    r5,4(fp)
  5c:    1949883a     add    r4,r3,r5
  60:    e1000015     stw    r4,0(fp)
  64:    df000e17     ldw    fp,56(sp)

00000068 <end>:
  68:    003fff06     br    68 <end>

0x00000030 <main>:      0x06c3ff04  movi sp, 4092 [dstData=0xffc dstReg=sp]
0x00000034 <main+0x4>:  0xdefff004  addi sp, sp, -64 [dstData=0xfbc dstReg=sp]
0x00000038 <main+0x8>:  0xdfc00f15  stw ra, 60(sp) [memAddr=0xff8 stData=0xa8]
0x0000003c <main+0xc>:  0xdf000e15  stw fp, 56(sp) [memAddr=0xff4 stData=0xdeadbeef]
0x00000040 <main+0x10>: 0xd839883a  mov fp, sp [dstData=0xfbc dstReg=fp]
0x00000044 <main+0x14>: 0x01000604  movi r4, 24 [dstData=0x18 dstReg=r4]
0x00000048 <main+0x18>: 0xe1000215  stw r4, 8(fp) [memAddr=0xfc4 stData=0x18]
0x0000004c <main+0x1c>: 0x010004c4  movi r4, 19 [dstData=0x13 dstReg=r4]
0x00000050 <main+0x20>: 0xe1000115  stw r4, 4(fp) [memAddr=0xfc0 stData=0x13]
0x00000054 <main+0x24>: 0xe0c00217  ldw r3, 8(fp) [memAddr=0xfc4 ldData=0x18 dstReg=r3]
0x00000058 <main+0x28>: 0xe1400117  ldw r5, 4(fp) [memAddr=0xfc0 ldData=0x13 dstReg=r5]
0x0000005c <main+0x2c>: 0x1949883a  add r4, r3, r5 [dstData=0x2b dstReg=r4]
0x00000060 <main+0x30>: 0xe1000015  stw r4, 0(fp) [memAddr=0xfbc stData=0x2b]
0x00000064 <main+0x34>: 0xdf000e17  ldw fp, 56(sp) [memAddr=0xff4 ldData=0xdeadbeef dstReg=fp]
0x00000068 <end>:       0x003fff06  br 0x68 <end>

Maintained by John Loomis, last updated Wed Apr 11 09:49:03 2007