linux/arch/xtensa/include/asm/asmmacro.h

154 lines
2.7 KiB
C

/*
* include/asm-xtensa/asmmacro.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2005 Tensilica Inc.
*/
#ifndef _XTENSA_ASMMACRO_H
#define _XTENSA_ASMMACRO_H
#include <variant/core.h>
/*
* Some little helpers for loops. Use zero-overhead-loops
* where applicable and if supported by the processor.
*
* __loopi ar, at, size, inc
* ar register initialized with the start address
* at scratch register used by macro
* size size immediate value
* inc increment
*
* __loops ar, as, at, inc_log2[, mask_log2][, cond][, ncond]
* ar register initialized with the start address
* as register initialized with the size
* at scratch register use by macro
* inc_log2 increment [in log2]
* mask_log2 mask [in log2]
* cond true condition (used in loop'cond')
* ncond false condition (used in b'ncond')
*
* __loop as
* restart loop. 'as' register must not have been modified!
*
* __endla ar, at, incr
* ar start address (modified)
* as scratch register used by macro
* inc increment
*/
/*
* loop for given size as immediate
*/
.macro __loopi ar, at, size, incr
#if XCHAL_HAVE_LOOPS
movi \at, ((\size + \incr - 1) / (\incr))
loop \at, 99f
#else
addi \at, \ar, \size
98:
#endif
.endm
/*
* loop for given size in register
*/
.macro __loops ar, as, at, incr_log2, mask_log2, cond, ncond
#if XCHAL_HAVE_LOOPS
.ifgt \incr_log2 - 1
addi \at, \as, (1 << \incr_log2) - 1
.ifnc \mask_log2,
extui \at, \at, \incr_log2, \mask_log2
.else
srli \at, \at, \incr_log2
.endif
.endif
loop\cond \at, 99f
#else
.ifnc \mask_log2,
extui \at, \as, \incr_log2, \mask_log2
.else
.ifnc \ncond,
srli \at, \as, \incr_log2
.endif
.endif
.ifnc \ncond,
b\ncond \at, 99f
.endif
.ifnc \mask_log2,
slli \at, \at, \incr_log2
add \at, \ar, \at
.else
add \at, \ar, \as
.endif
#endif
98:
.endm
/*
* loop from ar to ax
*/
.macro __loopt ar, as, at, incr_log2
#if XCHAL_HAVE_LOOPS
sub \at, \as, \ar
.ifgt \incr_log2 - 1
addi \at, \at, (1 << \incr_log2) - 1
srli \at, \at, \incr_log2
.endif
loop \at, 99f
#else
98:
#endif
.endm
/*
* restart loop. registers must be unchanged
*/
.macro __loop as
#if XCHAL_HAVE_LOOPS
loop \as, 99f
#else
98:
#endif
.endm
/*
* end of loop with no increment of the address.
*/
.macro __endl ar, as
#if !XCHAL_HAVE_LOOPS
bltu \ar, \as, 98b
#endif
99:
.endm
/*
* end of loop with increment of the address.
*/
.macro __endla ar, as, incr
addi \ar, \ar, \incr
__endl \ar \as
.endm
#endif /* _XTENSA_ASMMACRO_H */