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/* AArch64 virt. Drop EL2 to EL1 if we came up there, enable SIMD
(the compiler copies the genome with q registers), then stack, bss, C. */
.section .text.init
.global _start
_start:
mrs x0, CurrentEL
lsr x0, x0, #2
cmp x0, #2
b.ne 1f
mov x0, #(1 << 31) /* EL1 is AArch64 */
msr HCR_EL2, x0
mrs x0, CPTR_EL2
bic x0, x0, #(1 << 10) /* do not trap SIMD to EL2 */
msr CPTR_EL2, x0
mov x0, #0x3c5 /* EL1h, interrupts masked */
msr SPSR_EL2, x0
adr x0, 1f
msr ELR_EL2, x0
eret
1:
mrs x0, CPACR_EL1
orr x0, x0, #(3 << 20) /* FPEN: SIMD does not trap */
msr CPACR_EL1, x0
isb
ldr x0, =_stack_top
mov sp, x0
ldr x0, =_sbss
ldr x1, =_ebss
2:
cmp x0, x1
b.hs 3f
str xzr, [x0], #8
b 2b
3:
bl bare_main
4:
wfe
b 4b
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