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| /* SPDX-License-Identifier: GPL-2.0 */
| #include "common.h"
|
| .data
| .balign 8
| success_message:
| .ascii "success: switch_endian_test\n\0"
|
| .balign 8
| failure_message:
| .ascii "failure: switch_endian_test\n\0"
|
| .section ".toc"
| .balign 8
| pattern:
| .8byte 0x5555AAAA5555AAAA
|
| .text
| FUNC_START(_start)
| /* Load the pattern */
| ld r15, pattern@TOC(%r2)
|
| /* Setup CR, only CR2-CR4 are maintained */
| lis r3, 0x00FF
| ori r3, r3, 0xF000
| mtcr r3
|
| /* Load the pattern slightly modified into the registers */
| mr r3, r15
| addi r4, r15, 4
|
| addi r5, r15, 32
| mtlr r5
|
| addi r5, r15, 5
| addi r6, r15, 6
| addi r7, r15, 7
| addi r8, r15, 8
|
| /* r9 - r12 are clobbered */
|
| addi r13, r15, 13
| addi r14, r15, 14
|
| /* Skip r15 we're using it */
|
| addi r16, r15, 16
| addi r17, r15, 17
| addi r18, r15, 18
| addi r19, r15, 19
| addi r20, r15, 20
| addi r21, r15, 21
| addi r22, r15, 22
| addi r23, r15, 23
| addi r24, r15, 24
| addi r25, r15, 25
| addi r26, r15, 26
| addi r27, r15, 27
| addi r28, r15, 28
| addi r29, r15, 29
| addi r30, r15, 30
| addi r31, r15, 31
|
| /*
| * Call the syscall to switch endian.
| * It clobbers r9-r12, XER, CTR and CR0-1,5-7.
| */
| li r0, __NR_switch_endian
| sc
|
| tdi 0, 0, 0x48 // b +8 if the endian was switched
| b .Lfail // exit if endian didn't switch
|
| #include "check-reversed.S"
|
| /* Flip back, r0 already has the switch syscall number */
| .long 0x02000044 /* sc */
|
| #include "check.S"
|
| ld r4, success_message@got(%r2)
| li r5, 28 // strlen(success_message)
| li r14, 0 // exit status
| .Lout:
| li r0, __NR_write
| li r3, 1 /* stdout */
| sc
| li r0, __NR_exit
| mr r3, r14
| sc
| b .
|
| .Lfail:
| ld r4, failure_message@got(%r2)
| li r5, 28 // strlen(failure_message)
| li r14, 1
| b .Lout
|
|
