1 /*
2 ** Math library.
3 ** Copyright (C) 2005-2021 Mike Pall. See Copyright Notice in luajit.h
4 */
5
6 #include <math.h>
7
8 #define lib_math_c
9 #define LUA_LIB
10
11 #include "lua.h"
12 #include "lauxlib.h"
13 #include "lualib.h"
14
15 #include "lj_obj.h"
16 #include "lj_lib.h"
17 #include "lj_vm.h"
18 #include "lj_prng.h"
19
20 /* ------------------------------------------------------------------------ */
21
22 #define LJLIB_MODULE_math
23
24 LJLIB_ASM(math_abs) LJLIB_REC(.)
25 {
26 lj_lib_checknumber(L, 1);
27 return FFH_RETRY;
28 }
LJLIB_REC(math_round IRFPM_FLOOR)29 LJLIB_ASM_(math_floor) LJLIB_REC(math_round IRFPM_FLOOR)
30 LJLIB_ASM_(math_ceil) LJLIB_REC(math_round IRFPM_CEIL)
31
32 LJLIB_ASM(math_sqrt) LJLIB_REC(math_unary IRFPM_SQRT)
33 {
34 lj_lib_checknum(L, 1);
35 return FFH_RETRY;
36 }
LJLIB_REC(math_call IRCALL_log10)37 LJLIB_ASM_(math_log10) LJLIB_REC(math_call IRCALL_log10)
38 LJLIB_ASM_(math_exp) LJLIB_REC(math_call IRCALL_exp)
39 LJLIB_ASM_(math_sin) LJLIB_REC(math_call IRCALL_sin)
40 LJLIB_ASM_(math_cos) LJLIB_REC(math_call IRCALL_cos)
41 LJLIB_ASM_(math_tan) LJLIB_REC(math_call IRCALL_tan)
42 LJLIB_ASM_(math_asin) LJLIB_REC(math_call IRCALL_asin)
43 LJLIB_ASM_(math_acos) LJLIB_REC(math_call IRCALL_acos)
44 LJLIB_ASM_(math_atan) LJLIB_REC(math_call IRCALL_atan)
45 LJLIB_ASM_(math_sinh) LJLIB_REC(math_call IRCALL_sinh)
46 LJLIB_ASM_(math_cosh) LJLIB_REC(math_call IRCALL_cosh)
47 LJLIB_ASM_(math_tanh) LJLIB_REC(math_call IRCALL_tanh)
48 LJLIB_ASM_(math_frexp)
49 LJLIB_ASM_(math_modf)
50
51 LJLIB_ASM(math_log) LJLIB_REC(math_log)
52 {
53 double x = lj_lib_checknum(L, 1);
54 if (L->base+1 < L->top) {
55 double y = lj_lib_checknum(L, 2);
56 #ifdef LUAJIT_NO_LOG2
57 x = log(x); y = 1.0 / log(y);
58 #else
59 x = lj_vm_log2(x); y = 1.0 / lj_vm_log2(y);
60 #endif
61 setnumV(L->base-1-LJ_FR2, x*y); /* Do NOT join the expression to x / y. */
62 return FFH_RES(1);
63 }
64 return FFH_RETRY;
65 }
66
67 LJLIB_LUA(math_deg) /* function(x) return x * 57.29577951308232 end */
LJLIB_LUA(math_rad)68 LJLIB_LUA(math_rad) /* function(x) return x * 0.017453292519943295 end */
69
70 LJLIB_ASM(math_atan2) LJLIB_REC(.)
71 {
72 lj_lib_checknum(L, 1);
73 lj_lib_checknum(L, 2);
74 return FFH_RETRY;
75 }
76 LJLIB_ASM_(math_pow) LJLIB_REC(.)
LJLIB_ASM_(math_fmod)77 LJLIB_ASM_(math_fmod)
78
79 LJLIB_ASM(math_ldexp) LJLIB_REC(.)
80 {
81 lj_lib_checknum(L, 1);
82 #if LJ_DUALNUM && !LJ_TARGET_X86ORX64
83 lj_lib_checkint(L, 2);
84 #else
85 lj_lib_checknum(L, 2);
86 #endif
87 return FFH_RETRY;
88 }
89
LJLIB_REC(math_minmax IR_MIN)90 LJLIB_ASM(math_min) LJLIB_REC(math_minmax IR_MIN)
91 {
92 int i = 0;
93 do { lj_lib_checknumber(L, ++i); } while (L->base+i < L->top);
94 return FFH_RETRY;
95 }
96 LJLIB_ASM_(math_max) LJLIB_REC(math_minmax IR_MAX)
97
98 LJLIB_PUSH(3.14159265358979323846) LJLIB_SET(pi)
99 LJLIB_PUSH(1e310) LJLIB_SET(huge)
100
101 /* ------------------------------------------------------------------------ */
102
103 /* This implements a Tausworthe PRNG with period 2^223. Based on:
104 ** Tables of maximally-equidistributed combined LFSR generators,
105 ** Pierre L'Ecuyer, 1991, table 3, 1st entry.
106 ** Full-period ME-CF generator with L=64, J=4, k=223, N1=49.
107 */
108
109 /* Union needed for bit-pattern conversion between uint64_t and double. */
110 typedef union { uint64_t u64; double d; } U64double;
111
112 /* PRNG seeding function. */
random_seed(PRNGState * rs,double d)113 static void random_seed(PRNGState *rs, double d)
114 {
115 uint32_t r = 0x11090601; /* 64-k[i] as four 8 bit constants. */
116 int i;
117 for (i = 0; i < 4; i++) {
118 U64double u;
119 uint32_t m = 1u << (r&255);
120 r >>= 8;
121 u.d = d = d * 3.14159265358979323846 + 2.7182818284590452354;
122 if (u.u64 < m) u.u64 += m; /* Ensure k[i] MSB of u[i] are non-zero. */
123 rs->u[i] = u.u64;
124 }
125 for (i = 0; i < 10; i++)
126 (void)lj_prng_u64(rs);
127 }
128
129 /* PRNG extract function. */
130 LJLIB_PUSH(top-2) /* Upvalue holds userdata with PRNGState. */
LJLIB_CF(math_random)131 LJLIB_CF(math_random) LJLIB_REC(.)
132 {
133 int n = (int)(L->top - L->base);
134 PRNGState *rs = (PRNGState *)(uddata(udataV(lj_lib_upvalue(L, 1))));
135 U64double u;
136 double d;
137 u.u64 = lj_prng_u64d(rs);
138 d = u.d - 1.0;
139 if (n > 0) {
140 #if LJ_DUALNUM
141 int isint = 1;
142 double r1;
143 lj_lib_checknumber(L, 1);
144 if (tvisint(L->base)) {
145 r1 = (lua_Number)intV(L->base);
146 } else {
147 isint = 0;
148 r1 = numV(L->base);
149 }
150 #else
151 double r1 = lj_lib_checknum(L, 1);
152 #endif
153 if (n == 1) {
154 d = lj_vm_floor(d*r1) + 1.0; /* d is an int in range [1, r1] */
155 } else {
156 #if LJ_DUALNUM
157 double r2;
158 lj_lib_checknumber(L, 2);
159 if (tvisint(L->base+1)) {
160 r2 = (lua_Number)intV(L->base+1);
161 } else {
162 isint = 0;
163 r2 = numV(L->base+1);
164 }
165 #else
166 double r2 = lj_lib_checknum(L, 2);
167 #endif
168 d = lj_vm_floor(d*(r2-r1+1.0)) + r1; /* d is an int in range [r1, r2] */
169 }
170 #if LJ_DUALNUM
171 if (isint) {
172 setintV(L->top-1, lj_num2int(d));
173 return 1;
174 }
175 #endif
176 } /* else: d is a double in range [0, 1] */
177 setnumV(L->top++, d);
178 return 1;
179 }
180
181 /* PRNG seed function. */
182 LJLIB_PUSH(top-2) /* Upvalue holds userdata with PRNGState. */
LJLIB_CF(math_randomseed)183 LJLIB_CF(math_randomseed)
184 {
185 PRNGState *rs = (PRNGState *)(uddata(udataV(lj_lib_upvalue(L, 1))));
186 random_seed(rs, lj_lib_checknum(L, 1));
187 return 0;
188 }
189
190 /* ------------------------------------------------------------------------ */
191
192 #include "lj_libdef.h"
193
luaopen_math(lua_State * L)194 LUALIB_API int luaopen_math(lua_State *L)
195 {
196 PRNGState *rs = (PRNGState *)lua_newuserdata(L, sizeof(PRNGState));
197 lj_prng_seed_fixed(rs);
198 LJ_LIB_REG(L, LUA_MATHLIBNAME, math);
199 return 1;
200 }
201
202