/
integrator-crt0.S
47 lines (41 loc) · 1.05 KB
/
integrator-crt0.S
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/* .text is used instead of .section .text so it works with arm-aout too. */
.text
.global _start
.type _start, %function
_start:
/* Issue Angel SWI to read stack info */
mov r0, #0x16
adr r1, .LC0 /* point at ptr to 4 words to receive data */
swi 0x123456
ldr r0, .LC0 /* point at values read */
ldr r1, [r0, #8]
mov sp, r1
ldr r1, [r0, #12]
/* Zero the memory in the .bss section. */
mov a2, #0 /* Second arg: fill value */
mov fp, a2 /* Null frame pointer */
mov r7, a2 /* Null frame pointer for Thumb */
ldr a1, .LC1 /* First arg: start of memory block */
ldr a3, .LC2
sub a3, a3, a1 /* Third arg: length of block */
bl memset
mov r0, #0 /* no arguments */
mov r1, #0 /* no argv either */
bl main
b .
.LC0:
.word __heap_base__
.LC1:
.word __bss_start__
.LC2:
.word __bss_end__
/* Workspace for Angel calls. */
.data
/* Data returned by monitor SWI. */
.global __stack_base__
.global __heap_limit__
.global __heap_base__
__heap_base__: .word 0
__heap_limit__: .word 0
__stack_base__: .word 0
StackLimit: .word 0