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commit f87436760c751280d22ad3586ea0ea55e01bbad2 (HEAD -> master, master/master)
Date:   Tue Oct 29 11:35:16 2019 +0100

    MSBASIC: Don't copy CHRGET/CHRGET to zero page
    
    To free up more zero page and allow for a deeper stack. TXTPTR is
    still in zero page, so the program doesn't grow a lot. We now do:
    
                    sty SCRATCH
                    ldy #0
                    lda (TXTPTR),y
                    ldy SCRATCH
    
    instead of:
    
            TXTPTR=*+1
                    lda 60000       ; Self modifying operand
        
    All this incurs a slow down of 3.5% in benchmarks. This speed might
    be won back if we put the responsibility of saving Y to the caller
    (as must have been done in CBM-128 BASIC 7.0). But there are so many
    calling sites, this can be too much work.
    
    This benchmark now works:
    
            10 INPUT"HOW MANY DIGITS";N
            20 T=TIME
            30 L=INT(10*N/3)+1:DIM A(L)
            40 Z$="000000":T$="999999"
            50 FOR I=1TOL:A(I)=2:NEXT
            60 M=0:P=0
            70 FOR J=1TON:Q=0:K=2*L+1
            80 FOR I=L TO 1 STEP -1
            90 K=K-2:X=10*A(I)+Q*I
            100 Q=INT(X/K):A(I)=X-Q*K
            110 NEXT
            120 Y=INT(Q/10):A(1)=Q-10*Y:Q=Y
            130 IF Q=9 THEN M=M+1:GOTO170
            140 IF Q>9 THEN PRINT CHR$(49+P);LEFT$(Z$,M);:GOTO170
            150 PRINT CHR$(48+P);LEFT$(T$,M);
            160 P=Q:M=0
            170 NEXT
            180 PRINT CHR$(48+P)
            190 PRINT (TIME-T)/60
    
    Results:
    
            Micro-Soft BASIC        28 digits       510 s   (radix 10)
            Micro-Soft BASIC        14 digits       130 s   (radix 10)
    
    For reference:
    
            10 REM 28 digits of pi
            20 M=94:FOR I=0 TO M-1
            30 Z(I)=20:NEXTI:?"PI=";
            40 E=D%100:D=0:FORI=1TOM
            50 J=M-I:D=D+D*J+Z(J)*100
            60 A=J+J+1:Z(J)=D%A:D=D/A
            70 NEXTI:M=M-6:E=E+D/100
            80 ?E/10;:IF M=88 ?".";
            90 ?E%10;:IF M>10 GOTO 40
    
    Result:
    
            Tiny BASIC              28 digits       65 s    (radix 100)