1bit and 2bit LCD drivers: Low-level bit handling optimisations.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@10225 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 8 insertions, 2 deletions

diff --git a/firmware/drivers/lcd-recorder.c b/firmware/drivers/lcd-recorder.c
index d75b989dd2..22bfebe289 100644
--- a/firmware/drivers/lcd-recorder.c
+++ b/firmware/drivers/lcd-recorder.c
@@ -441,7 +441,10 @@ static void solidblock(unsigned char *address, unsigned mask, unsigned bits)
                        ICODE_ATTR;
 static void solidblock(unsigned char *address, unsigned mask, unsigned bits)
 {
-    *address = (*address & ~mask) | (bits & mask);
+    unsigned data = *(char*)address;
+
+    bits    ^= data;
+    *address = data ^ (bits & mask);
 }
 
 static void flipinvblock(unsigned char *address, unsigned mask, unsigned bits)
@@ -469,7 +472,10 @@ static void solidinvblock(unsigned char *address, unsigned mask, unsigned bits)
                           ICODE_ATTR;
 static void solidinvblock(unsigned char *address, unsigned mask, unsigned bits)
 {
-    *address = (*address & ~mask) | (~bits & mask);
+    unsigned data = *(char *)address;
+    
+    bits     = ~bits ^ data;
+    *address = data ^ (bits & mask);
 }
 
 lcd_blockfunc_type* const lcd_blockfuncs[8] = {