Minor math optimizations

2019-02-28 17:30:34 +01:00
parent 0ea78be056
commit cc6559c3f6
4 changed files with 16 additions and 10 deletions
--- a/libsrc/runtime/umul8x16r24.s
+++ b/libsrc/runtime/umul8x16r24.s
@@ -9,6 +9,7 @@

        .include        "zeropage.inc"

+        .macpack        cpu

 ;---------------------------------------------------------------------------
 ; 8x16 => 24 unsigned multiplication routine. Because the overhead for a
@@ -30,9 +31,14 @@ umul8x16r16:

 umul8x16r24m:
 umul8x16r16m:
+.if (.cpu .bitand ::CPU_ISET_65SC02)
+        stz     ptr1+1
+        stz     sreg
+.else
        ldx     #0
        stx     ptr1+1
        stx     sreg
+.endif

        ldy     #8              ; Number of bits
        ldx     ptr3            ; Get into register for speed