Changeset 998 for trunk

Timestamp:

12/04/10 08:12:39 (2 years ago)

Author:

reyalp

Message:

optimize reversebytes, from philmoz in ​http://chdk.setepontos.com/index.php?topic=5865.msg57559#msg57559

File:

• trunk/lib/armutil/reversebytes.S (modified) (1 diff)

trunk/lib/armutil/reversebytes.S

@@ -12 +12 @@
         
         // out = ((in>>8) & 0xFF00FF) | ((in&0xFF00FF) << 8);
-        mov     r3, r4, lsr #8  // r3 = in >> 8
-        and     r3, r3, r2              // r3 &= 0xFF00FF
+        and     r3, r2, r4, lsr #8              // r3 = 0xFF00FF & (in >> 8)
         and     r4, r4, r2              // r4 = in & 0xFF00FF
         orr     r4, r3, r4, asl #8 // out = r3 | (r4 << 8)
 
-        mov     r3, r5, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r5, lsr #8
         and     r5, r5, r2
         orr     r5, r3, r5, asl #8
 
-        mov     r3, r6, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r6, lsr #8
         and     r6, r6, r2
         orr     r6, r3, r6, asl #8
 
-        mov     r3, r7, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r7, lsr #8
         and     r7, r7, r2
         orr     r7, r3, r7, asl #8
 
-        mov     r3, r8, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r8, lsr #8
         and     r8, r8, r2
         orr     r8, r3, r8, asl #8
 
-        mov     r3, r9, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r9, lsr #8
         and     r9, r9, r2
         orr     r9, r3, r9, asl #8
 
-        mov     r3, r10, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r10, lsr #8
         and     r10, r10, r2
         orr     r10, r3, r10, asl #8
 
-        mov     r3, r11, lsr #8
-        and     r3, r3, r2
+        and     r3, r2, r11, lsr #8
         and     r11, r11, r2
         orr     r11, r3, r11, asl #8