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Use more compact loops.

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This commit is contained in:
Sven Michael Klose
2020-11-01 22:59:07 +01:00
committed by greg-king5
parent 99c0815cdb
commit f59cb9af06
13 changed files with 90 additions and 94 deletions
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15
libsrc/common/memcmp.s
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@@ -13,11 +13,11 @@ _memcmp:
; Calculate (-count-1) and store it into ptr3. This is some overhead here but
; saves time in the compare loop
eor #$FF
sta ptr3
txa
eor #$FF
sta ptr3+1
inx
stx ptr3+1
tax
inx
stx ptr3 ; Save count with each byte incremented separately
; Get the pointer parameters
@@ -33,7 +33,7 @@ _memcmp:
; Head of compare loop: Test for the end condition
Loop: inx ; Bump low byte of (-count-1)
Loop: dex ; Bump low byte of (-count-1)
beq BumpHiCnt ; Jump on overflow
; Do the compare
@@ -53,7 +53,7 @@ Comp: lda (ptr1),y
; Entry on low counter byte overflow
BumpHiCnt:
inc ptr3+1 ; Bump high byte of (-count-1)
dec ptr3+1 ; Bump high byte of (-count-1)
bne Comp ; Jump if not done
jmp return0 ; Count is zero, areas are identical
@@ -67,4 +67,3 @@ NotEqual:
Greater:
ldx #$01 ; Make result positive
rts