Fixed the comments to say where the actual Left-Hand Side and Right-Hand Side are put.

A description of positions [left, right] is appropriate more for C code than for Assembly code.  (A description of timing [first argument, second argument] is more appropriate for the way that Assembly code is written.)
This commit is contained in:
Greg King 2014-05-11 10:43:06 -04:00
parent 228b9d1718
commit f82a43b98d
5 changed files with 20 additions and 24 deletions

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@ -5,9 +5,7 @@
;
.export _cc65_umul8x8r16
.import umul8x8r16, popa
.include "zeropage.inc"
.import umul8x8r16, popa, ptr1:zp
;---------------------------------------------------------------------------

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@ -13,9 +13,9 @@
;---------------------------------------------------------------------------
; 16x16 => 32 signed multiplication routine.
;
; lhs rhs result result also in
; LHS RHS result result also in
; -------------------------------------------------------------
; ptr1 ax ax:sreg
; ax ptr1 ax:sreg
;
; There is probably a faster way to do this.
;

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@ -13,14 +13,14 @@
;---------------------------------------------------------------------------
; 16x16 => 32 unsigned multiplication routine. Because the overhead for a
; 16x16 => 16 unsigned multiplication routine is small, we will tag it with
; the matching labels as well.
; the matching labels, as well.
;
; routine lhs rhs result result also in
; routine LHS RHS result result also in
; -----------------------------------------------------------------------
; umul16x16r32 ptr1 ax ax:sreg ptr1:sreg
; umul16x16r32m ptr1 ptr3 ax:sreg ptr1:sreg
; umul16x16r16 ptr1 ax ax ptr1
; umul16x16r16m ptr1 ptr3 ax ptr1
; umul16x16r32 ax ptr1 ax:sreg ptr1:sreg
; umul16x16r32m ptr3 ptr1 ax:sreg ptr1:sreg
; umul16x16r16 ax ptr1 ax ptr1
; umul16x16r16m ptr3 ptr1 ax ptr1
;
; ptr3 is left intact by the routine.
;

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@ -13,14 +13,14 @@
;---------------------------------------------------------------------------
; 8x16 => 24 unsigned multiplication routine. Because the overhead for a
; 8x16 => 16 unsigned multiplication routine is small, we will tag it with
; the matching labels as well.
; the matching labels, as well.
;
; routine lhs rhs result result also in
; routine LHS RHS result result also in
; -----------------------------------------------------------------------
; umul8x16r24 ptr1-lo ax ax:sreg-lo ptr1:sreg-lo
; umul8x16r24m ptr1-lo ptr3 ax:sreg-lo ptr1:sreg-lo
; umul8x16r24 ax ptr1-low ax:sreg-low ptr1:sreg-low
; umul8x16r24m ptr3 ptr1-low ax:sreg-low ptr1:sreg-low
;
; ptr3 ist left intact by the routine.
; ptr3 is left intact by the routine.
;
umul8x16r24:

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@ -1,7 +1,7 @@
;
; Ullrich von Bassewitz, 2010-11-02
;
; CC65 runtime: 8x8 => 16 multiplication
; CC65 runtime: 8x8 => 16 unsigned multiplication
;
.export umul8x8r16, umul8x8r16m
@ -9,11 +9,11 @@
;---------------------------------------------------------------------------
; 8x8 => 16 multiplication routine.
; 8x8 => 16 unsigned multiplication routine.
;
; lhs rhs result result also in
; LHS RHS result result in also
; -------------------------------------------------------------
; ptr1-lo ptr3-lo ax ptr1
; .A (ptr3-low) ptr1-low .XA ptr1
;
umul8x8r16:
@ -21,7 +21,7 @@ umul8x8r16:
umul8x8r16m:
lda #0 ; Clear byte 1
ldy #8 ; Number of bits
lsr ptr1 ; Get first bit of lhs into carry
lsr ptr1 ; Get first bit of RHS into carry
@L0: bcc @L1
clc
adc ptr3
@ -30,8 +30,6 @@ umul8x8r16m:
dey
bne @L0
tax
stx ptr1+1 ; Result in a/x and ptr1
stx ptr1+1 ; Result in .XA and ptr1
lda ptr1 ; Load the result
rts ; Done