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3625ff3a AT |
1 | #ifndef VVS_STDLIB_MATH |
2 | #define VVS_STDLIB_MATH | |
3 | ||
2612f47f | 4 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
bb21580a AT |
5 | @ Name: |
6 | @ random (10000) | |
2612f47f | 7 | @ Description: |
f969012f DNR |
8 | @ Returns a pseudo-random number. |
9 | @ Before using for the first time, seed heap[0] with a non-zero value. | |
10 | @ This PRNG was taken from: https://en.wikipedia.org/wiki/Xorshift | |
2612f47f AT |
11 | @ Call Stack: |
12 | @ empty | |
13 | @ Return Stack: | |
14 | @ random number <-- TOS | |
15 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | |
f969012f | 16 | #include <logic.pvvs> |
2612f47f | 17 | NSSVTSSSSN | Mark: 10000 (random) |
b15f1da5 | 18 | |
f969012f | 19 | @ Fetch seed from heap[0]. |
b15f1da5 AT |
20 | SSSSN | PUSH 0 (ptr) |
21 | TTT | LOAD | |
b15f1da5 | 22 | |
f969012f DNR |
23 | @ Set TOS ^= TOS << 13 |
24 | SNS | DUP | |
25 | SSSTTSTN | PUSH +13 | |
26 | NSTTSTTSTN | JSR > 101101 (lshift) | |
27 | NSTTSTSTTN | JSR > 101011 (xor) | |
28 | ||
29 | @ Set TOS ^= TOS >> 7 | |
30 | SNS | DUP | |
31 | SSSTTTN | PUSH +7 | |
32 | NSTTSTTSSN | JSR > 101100 (rshift) | |
33 | NSTTSTSTTN | JSR > 101011 (xor) | |
34 | ||
35 | @ Set TOS ^= TOS << 17 | |
36 | SNS | DUP | |
37 | SSSTSSSTN | PUSH +17 | |
38 | NSTTSTTSTN | JSR > 101101 (lshift) | |
39 | NSTTSTSTTN | JSR > 101011 (xor) | |
40 | ||
41 | @ Store a copy of the new seed at heap[0] and return. | |
b15f1da5 AT |
42 | SNS | DUP |
43 | SSSSN | PUSH 0 (ptr) | |
44 | SNT | SWAP | |
45 | TTS | STORE | |
2612f47f AT |
46 | NTN | RTS |
47 | ||
3625ff3a | 48 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
bb21580a AT |
49 | @ Name: |
50 | @ abs (10001) | |
3625ff3a | 51 | @ Description: |
bb21580a | 52 | @ Returns the absolute value of its argument |
3625ff3a AT |
53 | @ Call Stack: |
54 | @ signed number <-- TOS | |
55 | @ Return Stack: | |
56 | @ abs(signed number) <-- TOS | |
57 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | |
58 | NSSVTSSSTN | Mark: 10001 (absolute value) | |
7359501c AT |
59 | |
60 | @ Catch -(2^63) as a special case since its absolute value will overflow | |
61 | @ a twos-complement 64-bit word. Return zero as though the absolute value | |
62 | @ overflowed to the bottom of the non-negative integers rather than | |
63 | @ overflowing back to the most negative integer. | |
64 | SNS | DUP | |
65 | SSTTSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSN | -(2^63) | |
66 | TSST | SUBTRACT | |
67 | NTSSSSTSSSTSSSSSSTSN | BRZ > 00010001 00000010 | |
68 | ||
69 | @ Handle all the other numbers. | |
3625ff3a AT |
70 | SNS | DUP |
71 | NTTSSSTSSSTSSSSSSSSN | BMI > 00010001 00000000 | |
72 | NSNSSSTSSSTSSSSSSSTN | JMP > 00010001 00000001 | |
73 | NSSVSSSTSSSTSSSSSSSSN | Mark: 00010001 00000000 | |
74 | SSTTN | PUSH -1 | |
75 | TSSN | MULTIPLY | |
76 | NSSVSSSTSSSTSSSSSSSTN | Mark: 00010001 00000001 | |
77 | NTN | RTS | |
78 | ||
7359501c AT |
79 | @ Special case: Push 0 and return. |
80 | NSSVSSSTSSSTSSSSSSTSN | Mark: 00010001 00000010 | |
81 | SNN | DROP | |
82 | SSSSN | PUSH 0 | |
83 | NTN | RTS | |
84 | ||
37372ed0 AT |
85 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
86 | @ Name: | |
87 | @ gcd (10010) | |
88 | @ Description: | |
89 | @ Returns greatest common divisor of X and Y. | |
90 | @ Call Stack: | |
91 | @ Y | |
92 | @ X <-- TOS | |
93 | @ Return Stack: | |
94 | @ gcd(X,Y) <-- TOS | |
95 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | |
96 | #include <stack.pvvs> | |
97 | NSSVTSSTSN | Mark: 10010 (gcd) | |
98 | ||
99 | @ Since 1 > -1, transform problem into gcd(abs(X),abs(Y)). | |
100 | SNT | SWAP | |
101 | NSTTSSSTN | JSR > 10001 (abs) | |
102 | SNT | SWAP | |
103 | NSTTSSSTN | JSR > 10001 (abs) | |
104 | ||
105 | @ Verify neither operand is zero. | |
106 | SNT | SWAP | |
107 | SNS | DUP | |
108 | NTSSSSTSSTSSSSSSSSSN | BRZ > 00010010 00000000 (gcd:zero input) | |
109 | SNT | SWAP | |
110 | SNS | DUP | |
111 | NTSSSSTSSTSSSSSSSSSN | BRZ > 00010010 00000000 (gcd:zero input) | |
112 | ||
113 | @ Verify X != Y and sort X,Y so the smaller is TOS. | |
114 | SNS | DUP | |
115 | SSSTTN | PUSH 3 | |
116 | NSTTTSSN | JSR > 1100 (deepdup) | |
117 | SNT | SWAP | |
118 | TSST | SUBTRACT | |
119 | @ TOS> Y-X, X, Y | |
120 | NTTSSSTSSTSSSSSSSSTN | BMI > 00010010 00000001 (gcd:swap inputs) | |
121 | NSNSSSTSSTSSSSSSSTSN | JMP > 00010010 00000010 (gcd:main loop) | |
122 | NSSVSSSTSSTSSSSSSSSTN | MARK: 00010010 00000001 (gcd:swap inputs) | |
123 | SNT | SWAP | |
124 | ||
125 | @ Main gcd loop. | |
126 | @ Euclidean algorithm. | |
127 | NSSVSSSTSSTSSSSSSSTSN | MARK: 00010010 00000010 (gcd:main loop) | |
128 | SNS | DUP | |
129 | SSSTTN | PUSH 3 | |
130 | NSTTSTSN | JSR > 1010 (stackrotate) | |
131 | TSTT | MODULO | |
132 | SNS | DUP | |
133 | NTSSSSTSSTSSSSSSSTTN | BRZ > 00010010 00000011 (gcd:loop termination) | |
134 | NSNSSSTSSTSSSSSSSTSN | JMP > 00010010 00000010 (gcd:main loop) | |
135 | NSSVSSSTSSTSSSSSSSTTN | MARK: 00010010 00000011 (gcd:loop termination) | |
136 | SNN | DROP | |
137 | NTN | RTS | |
138 | ||
139 | @ At least one operand was zero. | |
140 | @ Since we define gcd(a,0) = a, return the other operand. | |
141 | NSSVSSSTSSTSSSSSSSSSN | MARK: 00010010 00000000 (gcd:zero input) | |
142 | SNN | DROP | |
143 | NTN | RTS | |
144 | ||
3625ff3a | 145 | #endif |