ARM asm LCD and ATA driver functions: Don't save r12 as it is a scratch reg. Saves a bit of stack and execution time.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21795 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 8 insertions, 8 deletions

diff --git a/firmware/target/arm/as3525/sansa-clip/lcd-as-clip.S b/firmware/target/arm/as3525/sansa-clip/lcd-as-clip.S
index ed430178b9..5a52eb032c 100644
--- a/firmware/target/arm/as3525/sansa-clip/lcd-as-clip.S
+++ b/firmware/target/arm/as3525/sansa-clip/lcd-as-clip.S
@@ -39,15 +39,15 @@
  *   r3/r4 - current block of phases
  *   r5/r6 - current block of values
  *   r7 - lcd data accumulator
- *   r8 - phase signs mask
+ *   r12 - phase signs mask
  *   lr - lcd bridge address
  */
 
 lcd_grey_data:
-    stmfd   sp!, {r4-r8, lr}
-    mov     r8, #0x80
-    orr     r8, r8, r8, lsl #8
-    orr     r8, r8, r8, lsl #16
+    stmfd   sp!, {r4-r7, lr}
+    mov     r12, #0x80
+    orr     r12, r12, r12, lsl #8
+    orr     r12, r12, r12, lsl #16
 
     ldr     lr, =GPIOA_BASE
     mov     r3, #(1<<5)
@@ -70,7 +70,7 @@ lcd_grey_data:
     orrne   r7, r7, #0x2000
     tst     r3, #0x80000000
     orrne   r7, r7, #0x1000
-    bic     r3, r3, r8
+    bic     r3, r3, r12
     add     r3, r3, r5
 
     /* set bits 3..0 */
@@ -82,7 +82,7 @@ lcd_grey_data:
     orrne   r7, r7, #0x02
     tst     r4, #0x80000000
     orrne   r7, r7, #0x01
-    bic     r4, r4, r8
+    bic     r4, r4, r12
     add     r4, r4, r6
 
     stmia   r1!, {r3-r4}
@@ -102,5 +102,5 @@ lcd_grey_data:
     ands    r5, r5, #(1<<10)    @ wait until push fifo empties
     beq     1b
 
-    ldmfd   sp!, {r4-r8, pc}
+    ldmfd   sp!, {r4-r7, pc}
     .size   lcd_grey_data,.-lcd_grey_data