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.section ".text.exceptions"
.globl svc
svc:
cpsid aif
stmfd sp!, {r0-r12,lr}
ldr r0, [lr, #-4]
bic r0, #0xFF000000
// SVC #0 returns to supervisor mode
// TODO: Make supervisor mode return to a specific location
// (rather than to a user location) such as the kernel loop
cmp r0, #3
bgt svc_exit
beq svc_000003
cmp r0, #2
beq svc_000002
cmp r0, #1
beq svc_000001
cmp r0, #1
beq svc_000000
svc_000000:
cps #0x13
b svc_exit
svc_000001:
b svc_exit
svc_000002:
ldmfd sp!, {r0-r12,lr}
b schedule
svc_000003:
ldr r3, =scheduler
ldr r2, [r3, #0]
ldr r1, [r2, #8] // sp_base
cmp r1, #-1
beq svc_exit
ldr r3, =stacks_table
mov r0, #0
strb r0, [r3, r1]
// Free the thread after freeing the stack
mov r0, r2
bl free
b svc_exit
svc_exit:
ldmfd sp!, {r0-r12,pc}^
.section .data
svc_msg: .asciz "SVC Handler #"
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