This work is based in part on code from NetBSD libm, libc and kernel. The library is partly public domain and partly BSD-style licensed.
22 lines
432 B
ArmAsm
22 lines
432 B
ArmAsm
/* $NetBSD: flt_rounds.S,v 1.6 2011/09/30 17:42:34 christos Exp $ */
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#include <machine/asm.h>
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/*
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* 00 0 round to zero
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* 01 1 round to nearest
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* 10 2 round to positive infinity
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* 11 3 round to negative infinity
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*/
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.text
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_ALIGN_TEXT
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ENTRY(__flt_rounds)
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fnstcw -4(%rsp)
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movl -4(%rsp), %ecx
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shrl $9, %ecx
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andl $6, %ecx
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movl $0x2d, %eax /* 0x2d = 00.10.11.01 */
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sarl %cl, %eax /* 0,1,2,3 -> 1,3,2,0 */
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andl $3, %eax
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ret
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