Tiny optimizations for multiplication.

2020-08-29 16:21:45 +02:00 · 2020-08-29 16:21:45 +02:00 · f54e01781b
parent 5158ee2092
commit f54e01781b
2 changed files with 5 additions and 6 deletions
--- a/libsrc/runtime/lmul.s
+++ b/libsrc/runtime/lmul.s
@ -63,7 +63,7 @@ L0:     lsr     tmp4
        bcc     L1
        clc
        adc     ptr3
-        pha
+        tax
        lda     ptr3+1
        adc     tmp2
        sta     tmp2
@ -73,7 +73,7 @@ L0:     lsr     tmp4
        lda     ptr4+1
        adc     tmp4
        sta     tmp4
-        pla
+        txa
 L1:     dey
        bpl     L0
        lda     ptr1            ; Load the low result word
--- a/libsrc/runtime/umul8x16r24.s
+++ b/libsrc/runtime/umul8x16r24.s
@ -41,20 +41,19 @@ umul8x16r16m:
 .endif

        ldy     #8              ; Number of bits
-        ldx     ptr3            ; Get into register for speed
        lda     ptr1
        ror     a               ; Get next bit into carry
@L0:    bcc     @L1

        clc
-        pha
-        txa
+        tax
+        lda     ptr3
        adc     ptr1+1
        sta     ptr1+1
        lda     ptr3+1
        adc     sreg
        sta     sreg
-        pla
+        txa

@L1:    ror     sreg
        ror     ptr1+1