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for this (and three other) functions in this test Darwin's port is producing very different code from linux (and it's not especially obvious to me why it would, since I've not [at least inentionally] modified any vector stuff): | |
EDIT: explanation is that the Linux long double is 128 bit, where the Darwin ABI has long double same as double. | |
long double | |
check_l_pos (long double x, long double y) | |
{ | |
return x * __builtin_copysignl (1.0, y); | |
} | |
Darwin aarch64 port; | |
lC0: | |
.xword -9223372036854775808 | |
.xword -9223372036854775808 | |
.globl _check_l_pos | |
_check_l_pos: | |
adrp x0, lC0@PAGE | |
ldr q31, [x0, #lC0@PAGEOFF] | |
and v31.16b, v31.16b, v1.16b | |
eor v0.16b, v31.16b, v0.16b | |
ret | |
aarch64-none-linux-gnu: | |
.LC1: | |
.word 0 | |
.word 0 | |
.word 0 | |
.word 1073676288 | |
.LC2: | |
.word 0 | |
.word 0 | |
.word 0 | |
.word -1073807360 | |
.global __multf3 | |
.align 2 | |
.align 4 | |
.global check_l_pos | |
.type check_l_pos, %function | |
check_l_pos: | |
stp x29, x30, [sp, -32]! | |
adrp x0, .LC1 | |
add x0, x0, :lo12:.LC1 | |
mov x29, sp | |
str q1, [sp, 16] | |
mov v1.16b, v0.16b | |
ldr q0, [x0] | |
ldr x0, [sp, 24] | |
tbz x0, #63, .L5 | |
adrp x0, .LC2 | |
add x0, x0, :lo12:.LC2 | |
ldr q0, [x0] | |
.L5: | |
bl __multf3 | |
ldp x29, x30, [sp], 32 | |
ret | |
==== |
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