freebsd-nq/lib/libc/arm/aeabi/aeabi_asm_float.S
Andrew Turner cb8bcafa71 Add support for the __aeabi_c*cmp* functions. These are similar to the
existing functions with the exception they use the condition flags to
store the result.

Differential Revision:	https://reviews.freebsd.org/D872
Silence from:	current@ and numerics@
MFC after:	1 week
2014-10-14 14:27:51 +00:00

109 lines
2.7 KiB
ArmAsm

/*
* Copyright (C) 2014 Andrew Turner
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
#define PCR_Z (1 << 30)
#define PCR_C (1 << 29)
/*
* These functions return the result in the CPSR register.
*
* For __aeabi_cfcmple:
* Z C
* LT 0 0
* EQ 1 1
* else 0 1
*
* __aeabi_cfrcmple is the same as __aeabi_cfcmple, however the arguments
* have been swapped.
*/
ENTRY(__aeabi_cfcmple)
push {r4, r5, ip, lr}
/* Backup the input registers */
mov r4, r0
mov r5, r1
/* Is it less than? */
bl __aeabi_fcmplt
cmp r0, #1
bne 1f
/* Yes, clear Z and C */
msr cpsr_c, #(0)
b 99f
1:
/* Restore the input regsters for the next function call */
mov r0, r4
mov r1, r5
/* Is it equal? */
bl __aeabi_fcmpeq
cmp r0, #1
bne 2f
/* Yes, set Z and C */
msr cpsr_c, #(PCR_Z | PCR_C)
b 99f
2:
/* Not less than or equal, set C and clear Z */
msr cpsr_c, #(PCR_C)
99:
pop {r4, r5, ip, pc}
END(__aeabi_cfcmple)
ENTRY(__aeabi_cfrcmple)
/* Swap the arguments */
mov ip, r0
mov r0, r1
mov r1, ip
b __aeabi_cfcmple
END(__aeabi_cfrcmple)
/*
* This is just like __aeabi_cfcmple except it will not throw an exception
* in the presence of a quiet NaN. If either argument is a signalling NaN we
* will still signal.
*/
ENTRY(__aeabi_cfcmpeq)
/* Check if we can call __aeabi_cfcmple safely */
push {r0, r1, r2, lr}
bl __aeabi_cfcmpeq_helper
cmp r0, #1
pop {r0, r1, r2, lr}
beq 1f
bl __aeabi_cfcmple
RET
1:
msreq cpsr_c, #(PCR_C)
RET
END(__aeabi_cfcmpeq)