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Diffstat (limited to 'arch/arm/lib/findbit.S')
-rw-r--r--arch/arm/lib/findbit.S40
1 files changed, 30 insertions, 10 deletions
diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S
index 8c4defc4f3c..64f6bc1a913 100644
--- a/arch/arm/lib/findbit.S
+++ b/arch/arm/lib/findbit.S
@@ -25,7 +25,10 @@ ENTRY(_find_first_zero_bit_le)
teq r1, #0
beq 3f
mov r2, #0
-1: ldrb r3, [r0, r2, lsr #3]
+1:
+ ARM( ldrb r3, [r0, r2, lsr #3] )
+ THUMB( lsr r3, r2, #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
@@ -44,7 +47,9 @@ ENTRY(_find_next_zero_bit_le)
beq 3b
ands ip, r2, #7
beq 1b @ If new byte, goto old routine
- ldrb r3, [r0, r2, lsr #3]
+ ARM( ldrb r3, [r0, r2, lsr #3] )
+ THUMB( lsr r3, r2, #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
@@ -61,7 +66,10 @@ ENTRY(_find_first_bit_le)
teq r1, #0
beq 3f
mov r2, #0
-1: ldrb r3, [r0, r2, lsr #3]
+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
@@ -80,7 +88,9 @@ ENTRY(_find_next_bit_le)
beq 3b
ands ip, r2, #7
beq 1b @ If new byte, goto old routine
- ldrb r3, [r0, r2, lsr #3]
+ 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
@@ -95,7 +105,9 @@ ENTRY(_find_first_zero_bit_be)
beq 3f
mov r2, #0
1: eor r3, r2, #0x18 @ big endian byte ordering
- ldrb r3, [r0, r3, lsr #3]
+ 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
@@ -111,7 +123,9 @@ ENTRY(_find_next_zero_bit_be)
ands ip, r2, #7
beq 1b @ If new byte, goto old routine
eor r3, r2, #0x18 @ big endian byte ordering
- ldrb r3, [r0, r3, lsr #3]
+ 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
@@ -125,7 +139,9 @@ ENTRY(_find_first_bit_be)
beq 3f
mov r2, #0
1: eor r3, r2, #0x18 @ big endian byte ordering
- ldrb r3, [r0, r3, lsr #3]
+ 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
@@ -141,7 +157,9 @@ ENTRY(_find_next_bit_be)
ands ip, r2, #7
beq 1b @ If new byte, goto old routine
eor r3, r2, #0x18 @ big endian byte ordering
- ldrb r3, [r0, r3, lsr #3]
+ 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
@@ -156,8 +174,8 @@ ENDPROC(_find_next_bit_be)
*/
.L_found:
#if __LINUX_ARM_ARCH__ >= 5
- rsb r1, r3, #0
- and r3, r3, r1
+ rsb r0, r3, #0
+ and r3, r3, r0
clz r3, r3
rsb r3, r3, #31
add r0, r2, r3
@@ -172,5 +190,7 @@ ENDPROC(_find_next_bit_be)
addeq r2, r2, #1
mov r0, r2
#endif
+ cmp r1, r0 @ Clamp to maxbit
+ movlo r0, r1
mov pc, lr