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Luma3DS-3GX/exceptions/arm9/source/handlers.s

61 lines
1.5 KiB
ArmAsm

@
@ handlers.s
@ by TuxSH
@
@ This is part of Luma3DS, see LICENSE.txt for details
@
.macro GEN_HANDLER name
.global \name
.type \name, %function
\name:
stmfd sp!, {r0-r7} @ FIQ has its own r8-r14 regs
ldr r1, =\@ @ macro expansion counter
b _commonHandler
.size \name, . - \name
.endm
.text
.arm
.align 4
.global _commonHandler
.type _commonHandler, %function
_commonHandler:
mrs r2, spsr
mov r6, sp
mrs r3, cpsr
orr r3, #0x1c0 @ disable Imprecise Aborts, IRQ and FIQ (AIF)
ands r4, r2, #0xf @ get the mode that triggered the exception
moveq r4, #0xf @ usr => sys
bic r5, r3, #0xf
orr r5, r4
msr cpsr_c, r5 @ change processor mode
stmfd r6!, {r8-lr}
msr cpsr_c, r3 @ restore processor mode
mov sp, r6
stmfd sp!, {r2,lr} @ it's a bit of a mess, but we will fix that later
@ order of saved regs now: cpsr, pc + (2/4/8), r8-r14, r0-r7
mov r0, sp
b mainHandler
GEN_HANDLER FIQHandler
GEN_HANDLER undefinedInstructionHandler
GEN_HANDLER prefetchAbortHandler
GEN_HANDLER dataAbortHandler
.global setupStack
.type setupStack, %function
setupStack:
cmp r0, #0
moveq r0, #0xf @ usr => sys
mrs r2, cpsr
bic r3, r2, #0xf
orr r3, r0 @ processor mode
msr cpsr_c, r3 @ change processor mode
mov sp, r1
msr cpsr_c, r2 @ restore processor mode
bx lr