# output(): Hello, world.\n
|
# output(): Hello, world.\n
|
# mach(): all
|
# mach(): all
|
|
|
# Emit hello world while switching back and forth between arm/thumb.
|
# Emit hello world while switching back and forth between arm/thumb.
|
# ??? Unfinished
|
# ??? Unfinished
|
|
|
.macro invalid
|
.macro invalid
|
# This is "undefined" but it's not properly decoded yet.
|
# This is "undefined" but it's not properly decoded yet.
|
.word 0x07ffffff
|
.word 0x07ffffff
|
# This is stc which isn't recognized yet.
|
# This is stc which isn't recognized yet.
|
stc 0,cr0,[r0]
|
stc 0,cr0,[r0]
|
.endm
|
.endm
|
|
|
.global _start
|
.global _start
|
_start:
|
_start:
|
# Run some simple insns to confirm the engine is at least working.
|
# Run some simple insns to confirm the engine is at least working.
|
nop
|
nop
|
|
|
# Skip over output text.
|
# Skip over output text.
|
|
|
bl skip_output
|
bl skip_output
|
|
|
hello_text:
|
hello_text:
|
.asciz "Hello, world.\n"
|
.asciz "Hello, world.\n"
|
|
|
.p2align 2
|
.p2align 2
|
skip_output:
|
skip_output:
|
|
|
# Prime loop.
|
# Prime loop.
|
|
|
mov r4, r14
|
mov r4, r14
|
|
|
output_next:
|
output_next:
|
|
|
# Switch arm->thumb to output next chacter.
|
# Switch arm->thumb to output next chacter.
|
# At this point r4 must point to the next character to output.
|
# At this point r4 must point to the next character to output.
|
|
|
adr r0, into_thumb + 1
|
adr r0, into_thumb + 1
|
bx r0
|
bx r0
|
|
|
into_thumb:
|
into_thumb:
|
.thumb
|
.thumb
|
|
|
# Output a character.
|
# Output a character.
|
|
|
mov r0,#3 @ writec angel call
|
mov r0,#3 @ writec angel call
|
mov r1,r4
|
mov r1,r4
|
swi 0xab @ ??? Confirm number.
|
swi 0xab @ ??? Confirm number.
|
|
|
# Switch thumb->arm.
|
# Switch thumb->arm.
|
|
|
adr r5, back_to_arm
|
adr r5, back_to_arm
|
bx r5
|
bx r5
|
|
|
.p2align 2
|
.p2align 2
|
back_to_arm:
|
back_to_arm:
|
.arm
|
.arm
|
|
|
# Load next character, see if done.
|
# Load next character, see if done.
|
|
|
add r4,r4,#1
|
add r4,r4,#1
|
sub r3,r3,r3
|
sub r3,r3,r3
|
ldrb r5,[r4,r3]
|
ldrb r5,[r4,r3]
|
teq r5,#0
|
teq r5,#0
|
beq done
|
beq done
|
|
|
# Output a character (in arm mode).
|
# Output a character (in arm mode).
|
|
|
mov r0,#3
|
mov r0,#3
|
mov r1,r4
|
mov r1,r4
|
swi #0x123456
|
swi #0x123456
|
|
|
# Load next character, see if done.
|
# Load next character, see if done.
|
|
|
add r4,r4,#1
|
add r4,r4,#1
|
sub r3,r3,r3
|
sub r3,r3,r3
|
ldrb r5,[r4,r3]
|
ldrb r5,[r4,r3]
|
teq r5,#0
|
teq r5,#0
|
bne output_next
|
bne output_next
|
|
|
done:
|
done:
|
mov r0,#0x18
|
mov r0,#0x18
|
ldr r1,exit_code
|
ldr r1,exit_code
|
swi #0x123456
|
swi #0x123456
|
|
|
# If that fails, try to die with an invalid insn.
|
# If that fails, try to die with an invalid insn.
|
|
|
invalid
|
invalid
|
|
|
exit_code:
|
exit_code:
|
.word 0x20026
|
.word 0x20026
|
|
|
