uxn/projects/library/math32.tal

433 lines
12 KiB
Tal

( math32.tal )
( )
( This library supports arithmetic on 32-bit unsigned integers, )
( also known as long values. )
( )
( 32-bit long values are represented by two 16-bit short values: )
( )
( decimal hexadecimal uxn literals )
( 0 0x00000000 #0000 #0000 )
( 1 0x00000001 #0000 #0001 )
( 4660 0x00001234 #0000 #1234 )
( 65535 0x0000ffff #0000 #ffff )
( 65536 0x00010000 #0001 #0000 )
( 16777215 0x00ffffff #00ff #ffff )
( 4294967295 0xffffffff #ffff #ffff )
( )
( The most significant 16-bit, the "high bits", are stored first. )
( We document long values as x** -- equivalent to xhi* xlo*. )
( )
( Operations supported: )
( )
( NAME STACK EFFECT DEFINITION )
( add32 x** y** -> z** x + y )
( sub32 x** y** -> z** x - y )
( mul16 x* y* -> z** x * y )
( mul32 x** y** -> z** x * y )
( div32 x** y** -> q** x / y )
( mod32 x** y** -> r** x % y )
( divmod32 x** y** -> q** r** x / y, x % y )
( gcd32 x** y** -> z** gcd(x, y) )
( negate32 x** -> z** -x )
( lshift32 x** n^ -> z** x<<n )
( rshift32 x** n^ -> z** x>>n )
( and32 x** y** -> z** x & y )
( or32 x** y** -> z** x | y )
( xor32 x** y** -> z** x ^ y )
( complement32 x** -> z** ~x )
( eq32 x** y** -> bool^ x == y )
( ne32 x** y** -> bool^ x != y )
( is-zero32 x** -> bool^ x == 0 )
( non-zero32 x** -> bool^ x != 0 )
( lt32 x** y** -> bool^ x < y )
( gt32 x** y** -> bool^ x > y )
( lteq32 x** y** -> bool^ x <= y )
( gteq32 x** y** -> bool^ x >= y )
( bitcount8 x^ -> bool^ floor(log2(x))+1 )
( bitcount16 x* -> bool^ floor(log2(x))+1 )
( bitcount32 x** -> bool^ floor(log2(x))+1 )
( )
( In addition to the code this file uses 44 bytes of registers )
( to store temporary state: )
( )
( - shared memory, 16 bytes )
( - mul32 memory, 12 bytes )
( - _divmod32 memory, 16 bytes )
%COMPLEMENT32 { SWP2 #ffff EOR2 SWP2 #ffff EOR2 }
%DUP4 { OVR2 OVR2 }
%POP4 { POP2 POP2 }
( bitcount: number of bits needed to represent number )
( equivalent to floor[log2[x]] + 1 )
@bitcount8 ( x^ -> n^ )
#00 SWP ( n x )
&loop
DUP #00 EQU ( n x x=0 )
,&done JCN ( n x )
#01 SFT ( n x>>1 )
SWP INC SWP ( n+1 x>>1 )
,&loop JMP
&done
POP ( n )
JMP2r
@bitcount16 ( x* -> n^ )
SWP ( xlo xhi )
;bitcount8 JSR2 ( xlo nhi )
DUP #00 NEQ ( xlo nhi nhi!=0 )
,&hi-set JCN ( xlo nhi )
SWP ;bitcount8 JSR2 ADD ( nhi+nlo )
JMP2r
&hi-set
SWP POP #08 ADD ( nhi+8 )
JMP2r
@bitcount32 ( x** -> n^ )
SWP2 ( xlo* xhi* )
;bitcount16 JSR2 ( xlo* nhi )
DUP #00 NEQ ( xlo* nhi nhi!=0 )
,&hi-set JCN ( xlo* nhi )
ROT ROT ;bitcount16 JSR2 ADD JMP2r ( nhi+nlo )
&hi-set
ROT ROT POP2 #10 ADD ( nhi+16 )
JMP2r
( equality )
( x == y )
@eq32 ( xhi* xlo* yhi* ylo* -> bool^ )
ROT2 EQU2 STH
EQU2 STHr AND JMP2r
( x != y )
@ne32 ( xhi* xlo* yhi* ylo* -> bool^ )
ROT2 NEQ2 STH
NEQ2 STHr ORA JMP2r
( x == 0 )
@is-zero32 ( x** -> bool^ )
ORA2 #0000 EQU2 JMP2r
( x != 0 )
@non-zero32 ( x** -> bool^ )
ORA2 #0000 NEQ2 JMP2r
( comparisons )
( x < y )
@lt32 ( x** y** -> bool^ )
ROT2 SWP2 ( xhi yhi xlo ylo )
LTH2 ,&lt-lo JCN ( xhi yhi )
LTH2 JMP2r
&lt-lo
GTH2 #00 EQU JMP2r
( x <= y )
@lteq32 ( x** y** -> bool^ )
ROT2 SWP2 ( xhi yhi xlo ylo )
GTH2 ,&gt-lo JCN ( xhi yhi )
GTH2 #00 EQU JMP2r
&gt-lo
LTH2 JMP2r
( x > y )
@gt32 ( x** y** -> bool^ )
ROT2 SWP2 ( xhi yhi xlo ylo )
GTH2 ,&gt-lo JCN ( xhi yhi )
GTH2 JMP2r
&gt-lo
LTH2 #00 EQU JMP2r
( x > y )
@gteq32 ( x** y** -> bool^ )
ROT2 SWP2 ( xhi yhi xlo ylo )
LTH2 ,&lt-lo JCN ( xhi yhi )
LTH2 #00 EQU JMP2r
&lt-lo
GTH2 JMP2r
( bitwise operations )
( x & y )
@and32 ( xhi* xlo* yhi* ylo* -> xhi|yhi* xlo|ylo* )
ROT2 AND2 STH2 AND2 STH2r JMP2r
( x | y )
@or32 ( xhi* xlo* yhi* ylo* -> xhi|yhi* xlo|ylo* )
ROT2 ORA2 STH2 ORA2 STH2r JMP2r
( x ^ y )
@xor32 ( xhi* xlo* yhi* ylo* -> xhi|yhi* xlo|ylo* )
ROT2 EOR2 STH2 EOR2 STH2r JMP2r
( ~x )
@complement32 ( x** -> ~x** )
COMPLEMENT32 JMP2r
( temporary registers )
( shared by most operations, except mul32 and div32 )
@m32 [ &x0 $1 &x1 $1 &x2 $1 &x3 $1
&y0 $1 &y1 $1 &y2 $1 &y3 $1
&z0 $1 &z1 $1 &z2 $1 &z3 $1
&w0 $1 &w1 $1 &w2 $2 ]
( bit shifting )
( x >> n )
@rshift32 ( x** n^ -> x<<n )
DUP #08 LTH ;rshift32-0 JCN2 ( x n )
DUP #10 LTH ;rshift32-1 JCN2 ( x n )
DUP #18 LTH ;rshift32-2 JCN2 ( x n )
;rshift32-3 JMP2 ( x n )
JMP2r
( shift right by 0-7 bits )
@rshift32-0 ( x** n^ -> x<<n )
STHk SFT ;m32/z3 STA ( write z3 )
#00 STHkr SFT2 #00 ;m32/z3 LDA ORA2 ;m32/z2 STA2 ( write z2,z3 )
#00 STHkr SFT2 #00 ;m32/z2 LDA ORA2 ;m32/z1 STA2 ( write z1,z2 )
#00 STHr SFT2 #00 ;m32/z1 LDA ORA2 ( compute z0,z1 )
;m32/z2 LDA2
JMP2r
( shift right by 8-15 bits )
@rshift32-1 ( x** n^ -> x<<n )
#08 SUB STH POP
STHkr SFT ;m32/z3 STA ( write z3 )
#00 STHkr SFT2 #00 ;m32/z3 LDA ORA2 ;m32/z2 STA2 ( write z2,z3 )
#00 STHr SFT2 #00 ;m32/z2 LDA ORA2 ( compute z1,z2 )
#00 ROT ROT ;m32/z3 LDA
JMP2r
( shift right by 16-23 bits )
@rshift32-2 ( x** n^ -> x<<n )
#10 SUB STH POP2
STHkr SFT ;m32/z3 STA ( write z3 )
#00 STHr SFT2 #00 ;m32/z3 LDA ORA2 ( compute z2,z3 )
#0000 SWP2
JMP2r
( shift right by 16-23 bits )
@rshift32-3 ( x** n^ -> x<<n )
#18 SUB STH POP2 POP ( x0 )
#00 SWP #0000 SWP2 ( 00 00 00 x0 )
STHr SFT
JMP2r
( x << n )
@lshift32 ( x** n^ -> x<<n )
DUP #08 LTH ;lshift32-0 JCN2 ( x n )
DUP #10 LTH ;lshift32-1 JCN2 ( x n )
DUP #18 LTH ;lshift32-2 JCN2 ( x n )
;lshift32-3 JMP2 ( x n )
JMP2r
( shift left by 0-7 bits )
@lshift32-0 ( x** n^ -> x<<n )
#40 SFT STH ( stash n<<4 )
#00 SWP STHkr SFT2 ;m32/z2 STA2 ( store z2,z3 )
#00 SWP STHkr SFT2 #00 ;m32/z2 LDA ORA2 ;m32/z1 STA2 ( store z1,z2 )
#00 SWP STHkr SFT2 #00 ;m32/z1 LDA ORA2 ;m32/z0 STA2 ( store z0,z1 )
STHr SFT ;m32/z0 LDA ORA ( calculate z0 )
;m32/z1 LDA ;m32/z2 LDA2
JMP2r
( shift left by 8-15 bits )
@lshift32-1 ( x** n^ -> x<<n )
#08 SUB #40 SFT STH ( stash [n-8]<<4 )
#00 SWP STHkr SFT2 ;m32/z1 STA2 ( store z1,z2 )
#00 SWP STHkr SFT2 #00 ;m32/z1 LDA ORA2 ;m32/z0 STA2 ( store z0,z1 )
STHr SFT ;m32/z0 LDA ORA ( calculate z0 )
SWP POP ( x0 unused )
;m32/z1 LDA2 #00
JMP2r
( shift left by 16-23 bits )
@lshift32-2 ( x** n^ -> x<<n )
#10 SUB #40 SFT STH ( stash [n-16]<<4 )
#00 SWP STHkr SFT2 ;m32/z0 STA2 ( store z0,z1 )
STHr SFT ;m32/z0 LDA ORA ( calculate z0 )
STH POP2 STHr
;m32/z1 LDA #0000
JMP2r
( shift left by 24-31 bits )
@lshift32-3 ( x** n^ -> x<<n )
#18 SUB #40 SFT ( x0 x1 x2 x3 r=[n-24]<<4 )
SFT ( x0 x1 x2 x3<<r )
SWP2 POP2 SWP POP #0000 #00
JMP2r
( arithmetic )
( x + y )
@add32 ( xhi* xlo* yhi* ylo* -> zhi* zlo* )
;m32/y2 STA2 ;m32/y0 STA2 ( save ylo, yhi )
;m32/x2 STA2 ;m32/x0 STA2 ( save xlo, xhi )
#0000 #0000 ;m32/z0 STA2 ;m32/z2 STA2 ( reset zhi, zlo )
( x3 + y3 => z2z3 )
#00 ;m32/x3 LDA #00 ;m32/y3 LDA ADD2 ;m32/z2 STA2
( x2 + y2 + z2 => z1z2 )
#00 ;m32/x2 LDA ;m32/z1 LDA2 ADD2 ;m32/z1 STA2
#00 ;m32/y2 LDA ;m32/z1 LDA2 ADD2 ;m32/z1 STA2
( x1 + y1 + z1 => z0z1 )
#00 ;m32/x1 LDA ;m32/z0 LDA2 ADD2 ;m32/z0 STA2
#00 ;m32/y1 LDA ;m32/z0 LDA2 ADD2 ;m32/z0 STA2
( x0 + y0 + z0 => z0 )
;m32/x0 LDA ;m32/z0 LDA ADD ;m32/z0 STA
;m32/y0 LDA ;m32/z0 LDA ADD ;m32/z0 STA
( load zhi,zlo )
;m32/z0 LDA2 ;m32/z2 LDA2
JMP2r
( -x )
@negate32 ( x** -> -x** )
COMPLEMENT32
INC2 ( ~xhi -xlo )
DUP2 #0000 NEQ2 ( ~xhi -xlo non-zero? )
,&done JCN ( xlo non-zero => don't inc hi )
SWP2 INC2 SWP2 ( -xhi -xlo )
&done
JMP2r
( x - y )
@sub32 ( x** y** -> z** )
;negate32 JSR2 ;add32 JSR2 JMP2r
( 16-bit multiplication )
@mul16 ( x* y* -> z** )
;m32/y1 STA ;m32/y0 STA ( save ylo, yhi )
;m32/x1 STA ;m32/x0 STA ( save xlo, xhi )
#0000 #00 ;m32/z1 STA2 ;m32/z3 STA ( reset z1,z2,z3 )
#0000 #00 ;m32/w0 STA2 ;m32/w2 STA ( reset w0,w1,w2 )
( x1 * y1 => z1z2 )
#00 ;m32/x1 LDA #00 ;m32/y1 LDA MUL2 ;m32/z2 STA2
( x0 * y1 => z0z1 )
#00 ;m32/x0 LDA #00 ;m32/y1 LDA MUL2 ;m32/z1 LDA2 ADD2 ;m32/z1 STA2
( x1 * y0 => w1w2 )
#00 ;m32/x1 LDA #00 ;m32/y0 LDA MUL2 ;m32/w1 STA2
( x0 * y0 => w0w1 )
#00 ;m32/x0 LDA #00 ;m32/y0 LDA MUL2 ;m32/w0 LDA2 ADD2 ;m32/w0 STA2
( add z and a<<8 )
#00 ;m32/z1 LDA2 ;m32/z3 LDA
;m32/w0 LDA2 ;m32/w2 LDA #00
;add32 JSR2
JMP2r
( x * y )
@mul32 ( x** y** -> z** )
,&y1 STR2 ,&y0 STR2 ( save ylo, yhi )
,&x1 STR2 ,&x0 STR2 ( save xlo, xhi )
,&y1 LDR2 ,&x1 LDR2 ;mul16 JSR2 ( [x1*y1] )
,&z1 STR2 ,&z0 STR2 ( sum = x1*y1, save zlo, zhi )
,&y1 LDR2 ,&x0 LDR2 MUL2 ( [x0*y1]<<16 )
,&y0 LDR2 ,&x1 LDR2 MUL2 ( [x1*y0]<<16 )
( [x0*y0]<<32 will completely overflow )
ADD2 ,&z0 LDR2 ADD2 ( sum += x0*y1<<16 + x1*y0<<16 )
,&z1 LDR2
JMP2r
[ &x0 $2 &x1 $2
&y0 $2 &y1 $2
&z0 $2 &z1 $2 ]
@div32 ( x** y** -> q** )
;_divmod32 JSR2
;_divmod32/quo0 LDA2 ;_divmod32/quo1 LDA2
JMP2r
@mod32 ( x** y** -> r** )
;_divmod32 JSR2
;_divmod32/rem0 LDA2 ;_divmod32/rem1 LDA2
JMP2r
@divmod32 ( x** y** -> q** r** )
;_divmod32 JSR2
;_divmod32/quo0 LDA2 ;_divmod32/quo1 LDA2
;_divmod32/rem0 LDA2 ;_divmod32/rem1 LDA2
JMP2r
( calculate and store x / y and x % y )
@_divmod32 ( x** y** -> )
( store y and x for repeated use )
,&div1 STR2 ,&div0 STR2 ( y -> div )
,&rem1 STR2 ,&rem0 STR2 ( x -> rem )
( if x < y then the answer is 0 )
,&rem0 LDR2 ,&rem1 LDR2
,&div0 LDR2 ,&div1 LDR2
;lt32 JSR2 ,&is-zero JCN ,&not-zero JMP
&is-zero
#0000 ,&quo0 STR2 #0000 ,&quo1 STR2 JMP2r
( x >= y so the answer is >= 1 )
&not-zero
#0000 ,&quo0 STR2 #0000 ,&quo1 STR2 ( 0 -> quo )
( bitcount[x] - bitcount[y] determines the largest multiple of y to try )
,&rem0 LDR2 ,&rem1 LDR2 ;bitcount32 JSR2 ( rbits^ )
,&div0 LDR2 ,&div1 LDR2 ;bitcount32 JSR2 ( rbits^ dbits^ )
SUB ( shift=rbits-dits )
#00 DUP2 ( shift 0 shift 0 )
( 1<<shift -> cur )
#0000 #0001 ROT2 POP
;lshift32 JSR2 ,&cur1 STR2 ,&cur0 STR2
( div<<shift -> div )
,&div0 LDR2 ,&div1 LDR2 ROT2 POP
;lshift32 JSR2 ,&div1 STR2 ,&div0 STR2
,&loop JMP
[ &div0 $2 &div1 $2
&rem0 $2 &rem1 $2
&quo0 $2 &quo1 $2
&cur0 $2 &cur1 $2 ]
&loop
( if rem >= the current divisor, we can subtract it and add to quotient )
,&rem0 LDR2 ,&rem1 LDR2 ,&div0 LDR2 ,&div1 LDR2 ;lt32 JSR2 ( is rem < div? )
,&rem-lt JCN ( if rem < div skip this iteration )
( since rem >= div, we have found a multiple of y that divides x )
,&rem0 LDR2 ,&rem1 LDR2 ,&div0 LDR2 ,&div1 LDR2 ;sub32 JSR2 ,&rem1 STR2 ,&rem0 STR2 ( rem -= div )
,&quo0 LDR2 ,&quo1 LDR2 ,&cur0 LDR2 ,&cur1 LDR2 ;add32 JSR2 ,&quo1 STR2 ,&quo0 STR2 ( quo += cur )
&rem-lt
,&div0 LDR2 ,&div1 LDR2 #01 ;rshift32 JSR2 ,&div1 STR2 ,&div0 STR2 ( div >>= 1 )
,&cur0 LDR2 ,&cur1 LDR2 #01 ;rshift32 JSR2 ,&cur1 STR2 ,&cur0 STR2 ( cur >>= 1 )
,&cur0 LDR2 ,&cur1 LDR2 ;non-zero32 JSR2 ,&loop JCN ( if cur>0, loop. else we're done )
JMP2r
( greatest common divisor - euclidean algorithm )
@gcd32 ( x** y** -> z** )
&loop ( x y )
DUP4 ( x y y )
;is-zero32 JSR2 ( x y y=0? )
,&done JCN ( x y )
DUP4 ( x y y )
STH2 STH2 ( x y [y] )
;mod32 JSR2 ( r=x%y [y] )
STH2r ( rhi rlo yhi [ylo] )
ROT2 ( rlo yhi rhi [ylo] )
ROT2 ( yhi rhi rlo [ylo] )
STH2r ( yhi rhi rlo ylo )
ROT2 ( yhi rlo ylo rhi )
ROT2 ( yhi ylo rhi rlo )
,&loop JMP
&done
POP4 ( x )
JMP2r