banan-os/libc/math.S

26 lines
590 B
ArmAsm
Raw Normal View History

2023-05-10 22:35:20 +03:00
.global floorl;
floorl:
fldt 8(%rsp)
fnstenv -28(%rsp) /* store fpu environment */
/* We use here %edx although only the low 1 bits are defined.
But none of the operations should care and they are faster
than the 16 bit operations. */
movl $0x400,%edx /* round towards -oo */
orl -28(%rsp),%edx
andl $0xf7ff,%edx
movl %edx,-32(%rsp)
fldcw -32(%rsp) /* load modified control word */
frndint /* round */
/* Preserve "invalid" exceptions from sNaN input. */
fnstsw
andl $0x1, %eax
orl %eax, -24(%rsp)
fldenv -28(%rsp) /* restore original environment */
ret