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author | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-08-11 16:53:41 +0200 |
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committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-11-14 13:00:58 +0100 |
commit | 2953a3e187e054a4cfba4190a2037dc16b327372 (patch) | |
tree | 891b573875b4db880f99e1357e1d9edb3941ceea /arch/arm/lib | |
parent | ARM: findbit: provide more efficient ARMv7 implementation (diff) | |
download | linux-2953a3e187e054a4cfba4190a2037dc16b327372.tar.xz linux-2953a3e187e054a4cfba4190a2037dc16b327372.zip |
ARM: findbit: convert to macros
Since the pairs of _find_first and _find_next functions are pretty
similar, use macros to generate this code. This commit does not
change the generated code.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm/lib')
-rw-r--r-- | arch/arm/lib/findbit.S | 158 |
1 files changed, 42 insertions, 116 deletions
diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S index 256e095d490b..8280f66d38a5 100644 --- a/arch/arm/lib/findbit.S +++ b/arch/arm/lib/findbit.S @@ -14,155 +14,81 @@ #include <asm/assembler.h> .text -/* - * Purpose : Find a 'zero' bit - * Prototype: int find_first_zero_bit(void *addr, unsigned int maxbit); - */ -ENTRY(_find_first_zero_bit_le) - teq r1, #0 + .macro find_first, endian, set, name +ENTRY(_find_first_\name\()bit_\endian) + teq r1, #0 beq 3f mov r2, #0 1: + .ifc \endian, be + eor r3, r2, #0x18 + ARM( ldrb r3, [r0, r3, lsr #3] ) + THUMB( lsr r3, #3 ) + THUMB( ldrb r3, [r0, r3] ) + .else ARM( ldrb r3, [r0, r2, lsr #3] ) THUMB( lsr r3, r2, #3 ) THUMB( ldrb r3, [r0, r3] ) + .endif + .ifeq \set eors r3, r3, #0xff @ invert bits + .else + movs r3, r3 + .endif bne .L_found @ any now set - found zero bit add r2, r2, #8 @ next bit pointer 2: cmp r2, r1 @ any more? blo 1b 3: mov r0, r1 @ no free bits ret lr -ENDPROC(_find_first_zero_bit_le) +ENDPROC(_find_first_\name\()bit_\endian) + .endm -/* - * Purpose : Find next 'zero' bit - * Prototype: int find_next_zero_bit(void *addr, unsigned int maxbit, int offset) - */ -ENTRY(_find_next_zero_bit_le) + .macro find_next, endian, set, name +ENTRY(_find_next_\name\()bit_\endian) cmp r2, r1 bhs 3b ands ip, r2, #7 beq 1b @ If new byte, goto old routine + .ifc \endian, be + eor r3, r2, #0x18 + ARM( ldrb r3, [r0, r3, lsr #3] ) + THUMB( lsr r3, #3 ) + THUMB( ldrb r3, [r0, r3] ) + .else ARM( ldrb r3, [r0, r2, lsr #3] ) THUMB( lsr r3, r2, #3 ) THUMB( ldrb r3, [r0, r3] ) + .endif + .ifeq \set eor r3, r3, #0xff @ now looking for a 1 bit + .endif movs r3, r3, lsr ip @ shift off unused bits bne .L_found orr r2, r2, #7 @ if zero, then no bits here add r2, r2, #1 @ align bit pointer b 2b @ loop for next bit -ENDPROC(_find_next_zero_bit_le) +ENDPROC(_find_next_\name\()bit_\endian) + .endm -/* - * Purpose : Find a 'one' bit - * Prototype: int find_first_bit(const unsigned long *addr, unsigned int maxbit); - */ -ENTRY(_find_first_bit_le) - teq r1, #0 - beq 3f - mov r2, #0 -1: - ARM( ldrb r3, [r0, r2, lsr #3] ) - THUMB( lsr r3, r2, #3 ) - THUMB( ldrb r3, [r0, r3] ) - movs r3, r3 - bne .L_found @ any now set - found zero bit - add r2, r2, #8 @ next bit pointer -2: cmp r2, r1 @ any more? - blo 1b -3: mov r0, r1 @ no free bits - ret lr -ENDPROC(_find_first_bit_le) + .macro find_bit, endian, set, name + find_first \endian, \set, \name + find_next \endian, \set, \name + .endm -/* - * Purpose : Find next 'one' bit - * Prototype: int find_next_zero_bit(void *addr, unsigned int maxbit, int offset) - */ -ENTRY(_find_next_bit_le) - cmp r2, r1 - bhs 3b - ands ip, r2, #7 - beq 1b @ If new byte, goto old routine - ARM( ldrb r3, [r0, r2, lsr #3] ) - THUMB( lsr r3, r2, #3 ) - THUMB( ldrb r3, [r0, r3] ) - movs r3, r3, lsr ip @ shift off unused bits - bne .L_found - orr r2, r2, #7 @ if zero, then no bits here - add r2, r2, #1 @ align bit pointer - b 2b @ loop for next bit -ENDPROC(_find_next_bit_le) +/* _find_first_zero_bit_le and _find_next_zero_bit_le */ + find_bit le, 0, zero_ -#ifdef __ARMEB__ +/* _find_first_bit_le and _find_next_bit_le */ + find_bit le, 1 -ENTRY(_find_first_zero_bit_be) - teq r1, #0 - beq 3f - mov r2, #0 -1: eor r3, r2, #0x18 @ big endian byte ordering - ARM( ldrb r3, [r0, r3, lsr #3] ) - THUMB( lsr r3, #3 ) - THUMB( ldrb r3, [r0, r3] ) - eors r3, r3, #0xff @ invert bits - bne .L_found @ any now set - found zero bit - add r2, r2, #8 @ next bit pointer -2: cmp r2, r1 @ any more? - blo 1b -3: mov r0, r1 @ no free bits - ret lr -ENDPROC(_find_first_zero_bit_be) +#ifdef __ARMEB__ -ENTRY(_find_next_zero_bit_be) - cmp r2, r1 - bhs 3b - ands ip, r2, #7 - beq 1b @ If new byte, goto old routine - eor r3, r2, #0x18 @ big endian byte ordering - ARM( ldrb r3, [r0, r3, lsr #3] ) - THUMB( lsr r3, #3 ) - THUMB( ldrb r3, [r0, r3] ) - eor r3, r3, #0xff @ now looking for a 1 bit - movs r3, r3, lsr ip @ shift off unused bits - bne .L_found - orr r2, r2, #7 @ if zero, then no bits here - add r2, r2, #1 @ align bit pointer - b 2b @ loop for next bit -ENDPROC(_find_next_zero_bit_be) +/* _find_first_zero_bit_be and _find_next_zero_bit_be */ + find_bit be, 0, zero_ -ENTRY(_find_first_bit_be) - teq r1, #0 - beq 3f - mov r2, #0 -1: eor r3, r2, #0x18 @ big endian byte ordering - ARM( ldrb r3, [r0, r3, lsr #3] ) - THUMB( lsr r3, #3 ) - THUMB( ldrb r3, [r0, r3] ) - movs r3, r3 - bne .L_found @ any now set - found zero bit - add r2, r2, #8 @ next bit pointer -2: cmp r2, r1 @ any more? - blo 1b -3: mov r0, r1 @ no free bits - ret lr -ENDPROC(_find_first_bit_be) - -ENTRY(_find_next_bit_be) - cmp r2, r1 - bhs 3b - ands ip, r2, #7 - beq 1b @ If new byte, goto old routine - eor r3, r2, #0x18 @ big endian byte ordering - ARM( ldrb r3, [r0, r3, lsr #3] ) - THUMB( lsr r3, #3 ) - THUMB( ldrb r3, [r0, r3] ) - movs r3, r3, lsr ip @ shift off unused bits - bne .L_found - orr r2, r2, #7 @ if zero, then no bits here - add r2, r2, #1 @ align bit pointer - b 2b @ loop for next bit -ENDPROC(_find_next_bit_be) +/* _find_first_bit_be and _find_next_bit_be */ + find_bit be, 1 #endif |