[PATCH 3/5] ARM: findbit: convert to macros

[Russell King (Oracle)]

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@xxxxxxxxxxxxxxx>
---
 arch/arm/lib/findbit.S | 158 +++++++++++------------------------------
 1 file 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
 
-- 
2.30.2