src/lj_ffrecord.c

   1 /*
   2 ** Fast function call recorder.
   3 ** Copyright (C) 2005-2023 Mike Pall. See Copyright Notice in luajit.h
   4 */
   5
   6 #define lj_ffrecord_c
   7 #define LUA_CORE
   8
   9 #include "lj_obj.h"
  10
  11 #if LJ_HASJIT
  12
  13 #include "lj_err.h"
  14 #include "lj_str.h"
  15 #include "lj_tab.h"
  16 #include "lj_frame.h"
  17 #include "lj_bc.h"
  18 #include "lj_ff.h"
  19 #include "lj_ir.h"
  20 #include "lj_jit.h"
  21 #include "lj_ircall.h"
  22 #include "lj_iropt.h"
  23 #include "lj_trace.h"
  24 #include "lj_record.h"
  25 #include "lj_ffrecord.h"
  26 #include "lj_crecord.h"
  27 #include "lj_dispatch.h"
  28 #include "lj_vm.h"
  29 #include "lj_strscan.h"
  30
  31 /* Some local macros to save typing. Undef'd at the end. */
  32 #define IR(ref)                 (&J->cur.ir[(ref)])
  33
  34 /* Pass IR on to next optimization in chain (FOLD). */
  35 #define emitir(ot, a, b)        (lj_ir_set(J, (ot), (a), (b)), lj_opt_fold(J))
  36
  37 /* -- Fast function recording handlers ------------------------------------ */
  38
  39 /* Conventions for fast function call handlers:
  40 **
  41 ** The argument slots start at J->base[0]. All of them are guaranteed to be
  42 ** valid and type-specialized references. J->base[J->maxslot] is set to 0
  43 ** as a sentinel. The runtime argument values start at rd->argv[0].
  44 **
  45 ** In general fast functions should check for presence of all of their
  46 ** arguments and for the correct argument types. Some simplifications
  47 ** are allowed if the interpreter throws instead. But even if recording
  48 ** is aborted, the generated IR must be consistent (no zero-refs).
  49 **
  50 ** The number of results in rd->nres is set to 1. Handlers that return
  51 ** a different number of results need to override it. A negative value
  52 ** prevents return processing (e.g. for pending calls).
  53 **
  54 ** Results need to be stored starting at J->base[0]. Return processing
  55 ** moves them to the right slots later.
  56 **
  57 ** The per-ffid auxiliary data is the value of the 2nd part of the
  58 ** LJLIB_REC() annotation. This allows handling similar functionality
  59 ** in a common handler.
  60 */
  61
  62 /* Type of handler to record a fast function. */
  63 typedef void (LJ_FASTCALL *RecordFunc)(jit_State *J, RecordFFData *rd);
  64
  65 /* Get runtime value of int argument. */
  66 static int32_t argv2int(jit_State *J, TValue *o)
  67 {
  68   if (!lj_strscan_numberobj(o))
  69     lj_trace_err(J, LJ_TRERR_BADTYPE);
  70   return tvisint(o) ? intV(o) : lj_num2int(numV(o));
  71 }
  72
  73 /* Get runtime value of string argument. */
  74 static GCstr *argv2str(jit_State *J, TValue *o)
  75 {
  76   if (LJ_LIKELY(tvisstr(o))) {
  77     return strV(o);
  78   } else {
  79     GCstr *s;
  80     if (!tvisnumber(o))
  81       lj_trace_err(J, LJ_TRERR_BADTYPE);
  82     if (tvisint(o))
  83       s = lj_str_fromint(J->L, intV(o));
  84     else
  85       s = lj_str_fromnum(J->L, &o->n);
  86     setstrV(J->L, o, s);
  87     return s;
  88   }
  89 }
  90
  91 /* Return number of results wanted by caller. */
  92 static ptrdiff_t results_wanted(jit_State *J)
  93 {
  94   TValue *frame = J->L->base-1;
  95   if (frame_islua(frame))
  96     return (ptrdiff_t)bc_b(frame_pc(frame)[-1]) - 1;
  97   else
  98     return -1;
  99 }
 100
 101 /* Throw error for unsupported variant of fast function. */
 102 LJ_NORET static void recff_nyiu(jit_State *J)
 103 {
 104   setfuncV(J->L, &J->errinfo, J->fn);
 105   lj_trace_err_info(J, LJ_TRERR_NYIFFU);
 106 }
 107
 108 /* Fallback handler for all fast functions that are not recorded (yet). */
 109 static void LJ_FASTCALL recff_nyi(jit_State *J, RecordFFData *rd)
 110 {
 111   setfuncV(J->L, &J->errinfo, J->fn);
 112   lj_trace_err_info(J, LJ_TRERR_NYIFF);
 113   UNUSED(rd);
 114 }
 115
 116 /* C functions can have arbitrary side-effects and are not recorded (yet). */
 117 static void LJ_FASTCALL recff_c(jit_State *J, RecordFFData *rd)
 118 {
 119   setfuncV(J->L, &J->errinfo, J->fn);
 120   lj_trace_err_info(J, LJ_TRERR_NYICF);
 121   UNUSED(rd);
 122 }
 123
 124 /* -- Base library fast functions ----------------------------------------- */
 125
 126 static void LJ_FASTCALL recff_assert(jit_State *J, RecordFFData *rd)
 127 {
 128   /* Arguments already specialized. The interpreter throws for nil/false. */
 129   rd->nres = J->maxslot;  /* Pass through all arguments. */
 130 }
 131
 132 static void LJ_FASTCALL recff_type(jit_State *J, RecordFFData *rd)
 133 {
 134   /* Arguments already specialized. Result is a constant string. Neat, huh? */
 135   uint32_t t;
 136   if (tvisnumber(&rd->argv[0]))
 137     t = ~LJ_TNUMX;
 138   else if (LJ_64 && tvislightud(&rd->argv[0]))
 139     t = ~LJ_TLIGHTUD;
 140   else
 141     t = ~itype(&rd->argv[0]);
 142   J->base[0] = lj_ir_kstr(J, strV(&J->fn->c.upvalue[t]));
 143   UNUSED(rd);
 144 }
 145
 146 static void LJ_FASTCALL recff_getmetatable(jit_State *J, RecordFFData *rd)
 147 {
 148   TRef tr = J->base[0];
 149   if (tr) {
 150     RecordIndex ix;
 151     ix.tab = tr;
 152     copyTV(J->L, &ix.tabv, &rd->argv[0]);
 153     if (lj_record_mm_lookup(J, &ix, MM_metatable))
 154       J->base[0] = ix.mobj;
 155     else
 156       J->base[0] = ix.mt;
 157   }  /* else: Interpreter will throw. */
 158 }
 159
 160 static void LJ_FASTCALL recff_setmetatable(jit_State *J, RecordFFData *rd)
 161 {
 162   TRef tr = J->base[0];
 163   TRef mt = J->base[1];
 164   if (tref_istab(tr) && (tref_istab(mt) || (mt && tref_isnil(mt)))) {
 165     TRef fref, mtref;
 166     RecordIndex ix;
 167     ix.tab = tr;
 168     copyTV(J->L, &ix.tabv, &rd->argv[0]);
 169     lj_record_mm_lookup(J, &ix, MM_metatable); /* Guard for no __metatable. */
 170     fref = emitir(IRT(IR_FREF, IRT_P32), tr, IRFL_TAB_META);
 171     mtref = tref_isnil(mt) ? lj_ir_knull(J, IRT_TAB) : mt;
 172     emitir(IRT(IR_FSTORE, IRT_TAB), fref, mtref);
 173     if (!tref_isnil(mt))
 174       emitir(IRT(IR_TBAR, IRT_TAB), tr, 0);
 175     J->base[0] = tr;
 176     J->needsnap = 1;
 177   }  /* else: Interpreter will throw. */
 178 }
 179
 180 static void LJ_FASTCALL recff_rawget(jit_State *J, RecordFFData *rd)
 181 {
 182   RecordIndex ix;
 183   ix.tab = J->base[0]; ix.key = J->base[1];
 184   if (tref_istab(ix.tab) && ix.key) {
 185     ix.val = 0; ix.idxchain = 0;
 186     settabV(J->L, &ix.tabv, tabV(&rd->argv[0]));
 187     copyTV(J->L, &ix.keyv, &rd->argv[1]);
 188     J->base[0] = lj_record_idx(J, &ix);
 189   }  /* else: Interpreter will throw. */
 190 }
 191
 192 static void LJ_FASTCALL recff_rawset(jit_State *J, RecordFFData *rd)
 193 {
 194   RecordIndex ix;
 195   ix.tab = J->base[0]; ix.key = J->base[1]; ix.val = J->base[2];
 196   if (tref_istab(ix.tab) && ix.key && ix.val) {
 197     ix.idxchain = 0;
 198     settabV(J->L, &ix.tabv, tabV(&rd->argv[0]));
 199     copyTV(J->L, &ix.keyv, &rd->argv[1]);
 200     copyTV(J->L, &ix.valv, &rd->argv[2]);
 201     lj_record_idx(J, &ix);
 202     /* Pass through table at J->base[0] as result. */
 203   }  /* else: Interpreter will throw. */
 204 }
 205
 206 static void LJ_FASTCALL recff_rawequal(jit_State *J, RecordFFData *rd)
 207 {
 208   TRef tra = J->base[0];
 209   TRef trb = J->base[1];
 210   if (tra && trb) {
 211     int diff = lj_record_objcmp(J, tra, trb, &rd->argv[0], &rd->argv[1]);
 212     J->base[0] = diff ? TREF_FALSE : TREF_TRUE;
 213   }  /* else: Interpreter will throw. */
 214 }
 215
 216 #if LJ_52
 217 static void LJ_FASTCALL recff_rawlen(jit_State *J, RecordFFData *rd)
 218 {
 219   TRef tr = J->base[0];
 220   if (tref_isstr(tr))
 221     J->base[0] = emitir(IRTI(IR_FLOAD), tr, IRFL_STR_LEN);
 222   else if (tref_istab(tr))
 223     J->base[0] = lj_ir_call(J, IRCALL_lj_tab_len, tr);
 224   /* else: Interpreter will throw. */
 225   UNUSED(rd);
 226 }
 227 #endif
 228
 229 /* Determine mode of select() call. */
 230 int32_t lj_ffrecord_select_mode(jit_State *J, TRef tr, TValue *tv)
 231 {
 232   if (tref_isstr(tr) && *strVdata(tv) == '#') {  /* select('#', ...) */
 233     if (strV(tv)->len == 1) {
 234       emitir(IRTG(IR_EQ, IRT_STR), tr, lj_ir_kstr(J, strV(tv)));
 235     } else {
 236       TRef trptr = emitir(IRT(IR_STRREF, IRT_P32), tr, lj_ir_kint(J, 0));
 237       TRef trchar = emitir(IRT(IR_XLOAD, IRT_U8), trptr, IRXLOAD_READONLY);
 238       emitir(IRTG(IR_EQ, IRT_INT), trchar, lj_ir_kint(J, '#'));
 239     }
 240     return 0;
 241   } else {  /* select(n, ...) */
 242     int32_t start = argv2int(J, tv);
 243     if (start == 0) lj_trace_err(J, LJ_TRERR_BADTYPE);  /* A bit misleading. */
 244     return start;
 245   }
 246 }
 247
 248 static void LJ_FASTCALL recff_select(jit_State *J, RecordFFData *rd)
 249 {
 250   TRef tr = J->base[0];
 251   if (tr) {
 252     ptrdiff_t start = lj_ffrecord_select_mode(J, tr, &rd->argv[0]);
 253     if (start == 0) {  /* select('#', ...) */
 254       J->base[0] = lj_ir_kint(J, J->maxslot - 1);
 255     } else if (tref_isk(tr)) {  /* select(k, ...) */
 256       ptrdiff_t n = (ptrdiff_t)J->maxslot;
 257       if (start < 0) start += n;
 258       else if (start > n) start = n;
 259       if (start >= 1) {
 260         ptrdiff_t i;
 261         rd->nres = n - start;
 262         for (i = 0; i < n - start; i++)
 263           J->base[i] = J->base[start+i];
 264       }  /* else: Interpreter will throw. */
 265     } else {
 266       recff_nyiu(J);
 267     }
 268   }  /* else: Interpreter will throw. */
 269 }
 270
 271 static void LJ_FASTCALL recff_tonumber(jit_State *J, RecordFFData *rd)
 272 {
 273   TRef tr = J->base[0];
 274   TRef base = J->base[1];
 275   if (tr && !tref_isnil(base)) {
 276     base = lj_opt_narrow_toint(J, base);
 277     if (!tref_isk(base) || IR(tref_ref(base))->i != 10)
 278       recff_nyiu(J);
 279   }
 280   if (tref_isnumber_str(tr)) {
 281     if (tref_isstr(tr)) {
 282       TValue tmp;
 283       if (!lj_strscan_num(strV(&rd->argv[0]), &tmp))
 284         recff_nyiu(J);  /* Would need an inverted STRTO for this case. */
 285       tr = emitir(IRTG(IR_STRTO, IRT_NUM), tr, 0);
 286     }
 287 #if LJ_HASFFI
 288   } else if (tref_iscdata(tr)) {
 289     lj_crecord_tonumber(J, rd);
 290     return;
 291 #endif
 292   } else {
 293     tr = TREF_NIL;
 294   }
 295   J->base[0] = tr;
 296   UNUSED(rd);
 297 }
 298
 299 static TValue *recff_metacall_cp(lua_State *L, lua_CFunction dummy, void *ud)
 300 {
 301   jit_State *J = (jit_State *)ud;
 302   lj_record_tailcall(J, 0, 1);
 303   UNUSED(L); UNUSED(dummy);
 304   return NULL;
 305 }
 306
 307 static int recff_metacall(jit_State *J, RecordFFData *rd, MMS mm)
 308 {
 309   RecordIndex ix;
 310   ix.tab = J->base[0];
 311   copyTV(J->L, &ix.tabv, &rd->argv[0]);
 312   if (lj_record_mm_lookup(J, &ix, mm)) {  /* Has metamethod? */
 313     int errcode;
 314     TValue argv0;
 315     /* Temporarily insert metamethod below object. */
 316     J->base[1] = J->base[0];
 317     J->base[0] = ix.mobj;
 318     copyTV(J->L, &argv0, &rd->argv[0]);
 319     copyTV(J->L, &rd->argv[1], &rd->argv[0]);
 320     copyTV(J->L, &rd->argv[0], &ix.mobjv);
 321     /* Need to protect lj_record_tailcall because it may throw. */
 322     errcode = lj_vm_cpcall(J->L, NULL, J, recff_metacall_cp);
 323     /* Always undo Lua stack changes to avoid confusing the interpreter. */
 324     copyTV(J->L, &rd->argv[0], &argv0);
 325     if (errcode)
 326       lj_err_throw(J->L, errcode);  /* Propagate errors. */
 327     rd->nres = -1;  /* Pending call. */
 328     return 1;  /* Tailcalled to metamethod. */
 329   }
 330   return 0;
 331 }
 332
 333 static void LJ_FASTCALL recff_tostring(jit_State *J, RecordFFData *rd)
 334 {
 335   TRef tr = J->base[0];
 336   if (tref_isstr(tr)) {
 337     /* Ignore __tostring in the string base metatable. */
 338     /* Pass on result in J->base[0]. */
 339   } else if (!recff_metacall(J, rd, MM_tostring)) {
 340     if (tref_isnumber(tr)) {
 341       J->base[0] = emitir(IRT(IR_TOSTR, IRT_STR), tr, 0);
 342     } else if (tref_ispri(tr)) {
 343       J->base[0] = lj_ir_kstr(J, strV(&J->fn->c.upvalue[tref_type(tr)]));
 344     } else {
 345       recff_nyiu(J);
 346     }
 347   }
 348 }
 349
 350 static void LJ_FASTCALL recff_ipairs_aux(jit_State *J, RecordFFData *rd)
 351 {
 352   RecordIndex ix;
 353   ix.tab = J->base[0];
 354   if (tref_istab(ix.tab)) {
 355     if (!tvisnumber(&rd->argv[1]))  /* No support for string coercion. */
 356       lj_trace_err(J, LJ_TRERR_BADTYPE);
 357     setintV(&ix.keyv, numberVint(&rd->argv[1])+1);
 358     settabV(J->L, &ix.tabv, tabV(&rd->argv[0]));
 359     ix.val = 0; ix.idxchain = 0;
 360     ix.key = lj_opt_narrow_toint(J, J->base[1]);
 361     J->base[0] = ix.key = emitir(IRTI(IR_ADD), ix.key, lj_ir_kint(J, 1));
 362     J->base[1] = lj_record_idx(J, &ix);
 363     rd->nres = tref_isnil(J->base[1]) ? 0 : 2;
 364   }  /* else: Interpreter will throw. */
 365 }
 366
 367 static void LJ_FASTCALL recff_ipairs(jit_State *J, RecordFFData *rd)
 368 {
 369   TRef tr = J->base[0];
 370   if (!((LJ_52 || (LJ_HASFFI && tref_iscdata(tr))) &&
 371         recff_metacall(J, rd, MM_ipairs))) {
 372     if (tref_istab(tr)) {
 373       J->base[0] = lj_ir_kfunc(J, funcV(&J->fn->c.upvalue[0]));
 374       J->base[1] = tr;
 375       J->base[2] = lj_ir_kint(J, 0);
 376       rd->nres = 3;
 377     }  /* else: Interpreter will throw. */
 378   }
 379 }
 380
 381 static void LJ_FASTCALL recff_pcall(jit_State *J, RecordFFData *rd)
 382 {
 383   if (J->maxslot >= 1) {
 384     lj_record_call(J, 0, J->maxslot - 1);
 385     rd->nres = -1;  /* Pending call. */
 386   }  /* else: Interpreter will throw. */
 387 }
 388
 389 static TValue *recff_xpcall_cp(lua_State *L, lua_CFunction dummy, void *ud)
 390 {
 391   jit_State *J = (jit_State *)ud;
 392   lj_record_call(J, 1, J->maxslot - 2);
 393   UNUSED(L); UNUSED(dummy);
 394   return NULL;
 395 }
 396
 397 static void LJ_FASTCALL recff_xpcall(jit_State *J, RecordFFData *rd)
 398 {
 399   if (J->maxslot >= 2) {
 400     TValue argv0, argv1;
 401     TRef tmp;
 402     int errcode;
 403     /* Swap function and traceback. */
 404     tmp = J->base[0]; J->base[0] = J->base[1]; J->base[1] = tmp;
 405     copyTV(J->L, &argv0, &rd->argv[0]);
 406     copyTV(J->L, &argv1, &rd->argv[1]);
 407     copyTV(J->L, &rd->argv[0], &argv1);
 408     copyTV(J->L, &rd->argv[1], &argv0);
 409     /* Need to protect lj_record_call because it may throw. */
 410     errcode = lj_vm_cpcall(J->L, NULL, J, recff_xpcall_cp);
 411     /* Always undo Lua stack swap to avoid confusing the interpreter. */
 412     copyTV(J->L, &rd->argv[0], &argv0);
 413     copyTV(J->L, &rd->argv[1], &argv1);
 414     if (errcode)
 415       lj_err_throw(J->L, errcode);  /* Propagate errors. */
 416     rd->nres = -1;  /* Pending call. */
 417   }  /* else: Interpreter will throw. */
 418 }
 419
 420 /* -- Math library fast functions ----------------------------------------- */
 421
 422 static void LJ_FASTCALL recff_math_abs(jit_State *J, RecordFFData *rd)
 423 {
 424   TRef tr = lj_ir_tonum(J, J->base[0]);
 425   J->base[0] = emitir(IRTN(IR_ABS), tr, lj_ir_knum_abs(J));
 426   UNUSED(rd);
 427 }
 428
 429 /* Record rounding functions math.floor and math.ceil. */
 430 static void LJ_FASTCALL recff_math_round(jit_State *J, RecordFFData *rd)
 431 {
 432   TRef tr = J->base[0];
 433   if (!tref_isinteger(tr)) {  /* Pass through integers unmodified. */
 434     tr = emitir(IRTN(IR_FPMATH), lj_ir_tonum(J, tr), rd->data);
 435     /* Result is integral (or NaN/Inf), but may not fit an int32_t. */
 436     if (LJ_DUALNUM) {  /* Try to narrow using a guarded conversion to int. */
 437       lua_Number n = lj_vm_foldfpm(numberVnum(&rd->argv[0]), rd->data);
 438       if (n == (lua_Number)lj_num2int(n))
 439         tr = emitir(IRTGI(IR_CONV), tr, IRCONV_INT_NUM|IRCONV_CHECK);
 440     }
 441     J->base[0] = tr;
 442   }
 443 }
 444
 445 /* Record unary math.* functions, mapped to IR_FPMATH opcode. */
 446 static void LJ_FASTCALL recff_math_unary(jit_State *J, RecordFFData *rd)
 447 {
 448   J->base[0] = emitir(IRTN(IR_FPMATH), lj_ir_tonum(J, J->base[0]), rd->data);
 449 }
 450
 451 /* Record math.log. */
 452 static void LJ_FASTCALL recff_math_log(jit_State *J, RecordFFData *rd)
 453 {
 454   TRef tr = lj_ir_tonum(J, J->base[0]);
 455   if (J->base[1]) {
 456 #ifdef LUAJIT_NO_LOG2
 457     uint32_t fpm = IRFPM_LOG;
 458 #else
 459     uint32_t fpm = IRFPM_LOG2;
 460 #endif
 461     TRef trb = lj_ir_tonum(J, J->base[1]);
 462     tr = emitir(IRTN(IR_FPMATH), tr, fpm);
 463     trb = emitir(IRTN(IR_FPMATH), trb, fpm);
 464     trb = emitir(IRTN(IR_DIV), lj_ir_knum_one(J), trb);
 465     tr = emitir(IRTN(IR_MUL), tr, trb);
 466   } else {
 467     tr = emitir(IRTN(IR_FPMATH), tr, IRFPM_LOG);
 468   }
 469   J->base[0] = tr;
 470   UNUSED(rd);
 471 }
 472
 473 /* Record math.atan2. */
 474 static void LJ_FASTCALL recff_math_atan2(jit_State *J, RecordFFData *rd)
 475 {
 476   TRef tr = lj_ir_tonum(J, J->base[0]);
 477   TRef tr2 = lj_ir_tonum(J, J->base[1]);
 478   J->base[0] = emitir(IRTN(IR_ATAN2), tr, tr2);
 479   UNUSED(rd);
 480 }
 481
 482 /* Record math.ldexp. */
 483 static void LJ_FASTCALL recff_math_ldexp(jit_State *J, RecordFFData *rd)
 484 {
 485   TRef tr = lj_ir_tonum(J, J->base[0]);
 486 #if LJ_TARGET_X86ORX64
 487   TRef tr2 = lj_ir_tonum(J, J->base[1]);
 488 #else
 489   TRef tr2 = lj_opt_narrow_toint(J, J->base[1]);
 490 #endif
 491   J->base[0] = emitir(IRTN(IR_LDEXP), tr, tr2);
 492   UNUSED(rd);
 493 }
 494
 495 /* Record math.asin, math.acos, math.atan. */
 496 static void LJ_FASTCALL recff_math_atrig(jit_State *J, RecordFFData *rd)
 497 {
 498   TRef y = lj_ir_tonum(J, J->base[0]);
 499   TRef x = lj_ir_knum_one(J);
 500   uint32_t ffid = rd->data;
 501   if (ffid != FF_math_atan) {
 502     TRef tmp = emitir(IRTN(IR_MUL), y, y);
 503     tmp = emitir(IRTN(IR_SUB), x, tmp);
 504     tmp = emitir(IRTN(IR_FPMATH), tmp, IRFPM_SQRT);
 505     if (ffid == FF_math_asin) { x = tmp; } else { x = y; y = tmp; }
 506   }
 507   J->base[0] = emitir(IRTN(IR_ATAN2), y, x);
 508 }
 509
 510 static void LJ_FASTCALL recff_math_htrig(jit_State *J, RecordFFData *rd)
 511 {
 512   TRef tr = lj_ir_tonum(J, J->base[0]);
 513   J->base[0] = emitir(IRTN(IR_CALLN), tr, rd->data);
 514 }
 515
 516 static void LJ_FASTCALL recff_math_modf(jit_State *J, RecordFFData *rd)
 517 {
 518   TRef tr = J->base[0];
 519   if (tref_isinteger(tr)) {
 520     J->base[0] = tr;
 521     J->base[1] = lj_ir_kint(J, 0);
 522   } else {
 523     TRef trt;
 524     tr = lj_ir_tonum(J, tr);
 525     trt = emitir(IRTN(IR_FPMATH), tr, IRFPM_TRUNC);
 526     J->base[0] = trt;
 527     J->base[1] = emitir(IRTN(IR_SUB), tr, trt);
 528   }
 529   rd->nres = 2;
 530 }
 531
 532 static void LJ_FASTCALL recff_math_degrad(jit_State *J, RecordFFData *rd)
 533 {
 534   TRef tr = lj_ir_tonum(J, J->base[0]);
 535   TRef trm = lj_ir_knum(J, numV(&J->fn->c.upvalue[0]));
 536   J->base[0] = emitir(IRTN(IR_MUL), tr, trm);
 537   UNUSED(rd);
 538 }
 539
 540 static void LJ_FASTCALL recff_math_pow(jit_State *J, RecordFFData *rd)
 541 {
 542   J->base[0] = lj_opt_narrow_pow(J, J->base[0], J->base[1],
 543                                  &rd->argv[0], &rd->argv[1]);
 544   UNUSED(rd);
 545 }
 546
 547 static void LJ_FASTCALL recff_math_minmax(jit_State *J, RecordFFData *rd)
 548 {
 549   TRef tr = lj_ir_tonumber(J, J->base[0]);
 550   uint32_t op = rd->data;
 551   BCReg i;
 552   for (i = 1; J->base[i] != 0; i++) {
 553     TRef tr2 = lj_ir_tonumber(J, J->base[i]);
 554     IRType t = IRT_INT;
 555     if (!(tref_isinteger(tr) && tref_isinteger(tr2))) {
 556       if (tref_isinteger(tr)) tr = emitir(IRTN(IR_CONV), tr, IRCONV_NUM_INT);
 557       if (tref_isinteger(tr2)) tr2 = emitir(IRTN(IR_CONV), tr2, IRCONV_NUM_INT);
 558       t = IRT_NUM;
 559     }
 560     tr = emitir(IRT(op, t), tr, tr2);
 561   }
 562   J->base[0] = tr;
 563 }
 564
 565 static void LJ_FASTCALL recff_math_random(jit_State *J, RecordFFData *rd)
 566 {
 567   GCudata *ud = udataV(&J->fn->c.upvalue[0]);
 568   TRef tr, one;
 569   lj_ir_kgc(J, obj2gco(ud), IRT_UDATA);  /* Prevent collection. */
 570   tr = lj_ir_call(J, IRCALL_lj_math_random_step, lj_ir_kptr(J, uddata(ud)));
 571   one = lj_ir_knum_one(J);
 572   tr = emitir(IRTN(IR_SUB), tr, one);
 573   if (J->base[0]) {
 574     TRef tr1 = lj_ir_tonum(J, J->base[0]);
 575     if (J->base[1]) {  /* d = floor(d*(r2-r1+1.0)) + r1 */
 576       TRef tr2 = lj_ir_tonum(J, J->base[1]);
 577       tr2 = emitir(IRTN(IR_SUB), tr2, tr1);
 578       tr2 = emitir(IRTN(IR_ADD), tr2, one);
 579       tr = emitir(IRTN(IR_MUL), tr, tr2);
 580       tr = emitir(IRTN(IR_FPMATH), tr, IRFPM_FLOOR);
 581       tr = emitir(IRTN(IR_ADD), tr, tr1);
 582     } else {  /* d = floor(d*r1) + 1.0 */
 583       tr = emitir(IRTN(IR_MUL), tr, tr1);
 584       tr = emitir(IRTN(IR_FPMATH), tr, IRFPM_FLOOR);
 585       tr = emitir(IRTN(IR_ADD), tr, one);
 586     }
 587   }
 588   J->base[0] = tr;
 589   UNUSED(rd);
 590 }
 591
 592 /* -- Bit library fast functions ------------------------------------------ */
 593
 594 /* Record unary bit.tobit, bit.bnot, bit.bswap. */
 595 static void LJ_FASTCALL recff_bit_unary(jit_State *J, RecordFFData *rd)
 596 {
 597   TRef tr = lj_opt_narrow_tobit(J, J->base[0]);
 598   J->base[0] = (rd->data == IR_TOBIT) ? tr : emitir(IRTI(rd->data), tr, 0);
 599 }
 600
 601 /* Record N-ary bit.band, bit.bor, bit.bxor. */
 602 static void LJ_FASTCALL recff_bit_nary(jit_State *J, RecordFFData *rd)
 603 {
 604   TRef tr = lj_opt_narrow_tobit(J, J->base[0]);
 605   uint32_t op = rd->data;
 606   BCReg i;
 607   for (i = 1; J->base[i] != 0; i++)
 608     tr = emitir(IRTI(op), tr, lj_opt_narrow_tobit(J, J->base[i]));
 609   J->base[0] = tr;
 610 }
 611
 612 /* Record bit shifts. */
 613 static void LJ_FASTCALL recff_bit_shift(jit_State *J, RecordFFData *rd)
 614 {
 615   TRef tr = lj_opt_narrow_tobit(J, J->base[0]);
 616   TRef tsh = lj_opt_narrow_tobit(J, J->base[1]);
 617   IROp op = (IROp)rd->data;
 618   if (!(op < IR_BROL ? LJ_TARGET_MASKSHIFT : LJ_TARGET_MASKROT) &&
 619       !tref_isk(tsh))
 620     tsh = emitir(IRTI(IR_BAND), tsh, lj_ir_kint(J, 31));
 621 #ifdef LJ_TARGET_UNIFYROT
 622   if (op == (LJ_TARGET_UNIFYROT == 1 ? IR_BROR : IR_BROL)) {
 623     op = LJ_TARGET_UNIFYROT == 1 ? IR_BROL : IR_BROR;
 624     tsh = emitir(IRTI(IR_NEG), tsh, tsh);
 625   }
 626 #endif
 627   J->base[0] = emitir(IRTI(op), tr, tsh);
 628 }
 629
 630 /* -- String library fast functions --------------------------------------- */
 631
 632 static void LJ_FASTCALL recff_string_len(jit_State *J, RecordFFData *rd)
 633 {
 634   J->base[0] = emitir(IRTI(IR_FLOAD), lj_ir_tostr(J, J->base[0]), IRFL_STR_LEN);
 635   UNUSED(rd);
 636 }
 637
 638 /* Handle string.byte (rd->data = 0) and string.sub (rd->data = 1). */
 639 static void LJ_FASTCALL recff_string_range(jit_State *J, RecordFFData *rd)
 640 {
 641   TRef trstr = lj_ir_tostr(J, J->base[0]);
 642   TRef trlen = emitir(IRTI(IR_FLOAD), trstr, IRFL_STR_LEN);
 643   TRef tr0 = lj_ir_kint(J, 0);
 644   TRef trstart, trend;
 645   GCstr *str = argv2str(J, &rd->argv[0]);
 646   int32_t start, end;
 647   if (rd->data) {  /* string.sub(str, start [,end]) */
 648     start = argv2int(J, &rd->argv[1]);
 649     trstart = lj_opt_narrow_toint(J, J->base[1]);
 650     trend = J->base[2];
 651     if (tref_isnil(trend)) {
 652       trend = lj_ir_kint(J, -1);
 653       end = -1;
 654     } else {
 655       trend = lj_opt_narrow_toint(J, trend);
 656       end = argv2int(J, &rd->argv[2]);
 657     }
 658   } else {  /* string.byte(str, [,start [,end]]) */
 659     if (tref_isnil(J->base[1])) {
 660       start = 1;
 661       trstart = lj_ir_kint(J, 1);
 662     } else {
 663       start = argv2int(J, &rd->argv[1]);
 664       trstart = lj_opt_narrow_toint(J, J->base[1]);
 665     }
 666     if (J->base[1] && !tref_isnil(J->base[2])) {
 667       trend = lj_opt_narrow_toint(J, J->base[2]);
 668       end = argv2int(J, &rd->argv[2]);
 669     } else {
 670       trend = trstart;
 671       end = start;
 672     }
 673   }
 674   if (end < 0) {
 675     emitir(IRTGI(IR_LT), trend, tr0);
 676     trend = emitir(IRTI(IR_ADD), emitir(IRTI(IR_ADD), trlen, trend),
 677                    lj_ir_kint(J, 1));
 678     end = end+(int32_t)str->len+1;
 679   } else if ((MSize)end <= str->len) {
 680     emitir(IRTGI(IR_ULE), trend, trlen);
 681   } else {
 682     emitir(IRTGI(IR_GT), trend, trlen);
 683     end = (int32_t)str->len;
 684     trend = trlen;
 685   }
 686   if (start < 0) {
 687     emitir(IRTGI(IR_LT), trstart, tr0);
 688     trstart = emitir(IRTI(IR_ADD), trlen, trstart);
 689     start = start+(int32_t)str->len;
 690     emitir(start < 0 ? IRTGI(IR_LT) : IRTGI(IR_GE), trstart, tr0);
 691     if (start < 0) {
 692       trstart = tr0;
 693       start = 0;
 694     }
 695   } else {
 696     if (start == 0) {
 697       emitir(IRTGI(IR_EQ), trstart, tr0);
 698       trstart = tr0;
 699     } else {
 700       trstart = emitir(IRTI(IR_ADD), trstart, lj_ir_kint(J, -1));
 701       emitir(IRTGI(IR_GE), trstart, tr0);
 702       start--;
 703     }
 704   }
 705   if (rd->data) {  /* Return string.sub result. */
 706     if (end - start >= 0) {
 707       /* Also handle empty range here, to avoid extra traces. */
 708       TRef trptr, trslen = emitir(IRTI(IR_SUB), trend, trstart);
 709       emitir(IRTGI(IR_GE), trslen, tr0);
 710       trptr = emitir(IRT(IR_STRREF, IRT_P32), trstr, trstart);
 711       J->base[0] = emitir(IRT(IR_SNEW, IRT_STR), trptr, trslen);
 712     } else {  /* Range underflow: return empty string. */
 713       emitir(IRTGI(IR_LT), trend, trstart);
 714       J->base[0] = lj_ir_kstr(J, lj_str_new(J->L, strdata(str), 0));
 715     }
 716   } else {  /* Return string.byte result(s). */
 717     ptrdiff_t i, len = end - start;
 718     if (len > 0) {
 719       TRef trslen = emitir(IRTI(IR_SUB), trend, trstart);
 720       emitir(IRTGI(IR_EQ), trslen, lj_ir_kint(J, (int32_t)len));
 721       if (J->baseslot + len > LJ_MAX_JSLOTS)
 722         lj_trace_err_info(J, LJ_TRERR_STACKOV);
 723       rd->nres = len;
 724       for (i = 0; i < len; i++) {
 725         TRef tmp = emitir(IRTI(IR_ADD), trstart, lj_ir_kint(J, (int32_t)i));
 726         tmp = emitir(IRT(IR_STRREF, IRT_P32), trstr, tmp);
 727         J->base[i] = emitir(IRT(IR_XLOAD, IRT_U8), tmp, IRXLOAD_READONLY);
 728       }
 729     } else {  /* Empty range or range underflow: return no results. */
 730       emitir(IRTGI(IR_LE), trend, trstart);
 731       rd->nres = 0;
 732     }
 733   }
 734 }
 735
 736 /* -- Table library fast functions ---------------------------------------- */
 737
 738 static void LJ_FASTCALL recff_table_getn(jit_State *J, RecordFFData *rd)
 739 {
 740   if (tref_istab(J->base[0]))
 741     J->base[0] = lj_ir_call(J, IRCALL_lj_tab_len, J->base[0]);
 742   /* else: Interpreter will throw. */
 743   UNUSED(rd);
 744 }
 745
 746 static void LJ_FASTCALL recff_table_remove(jit_State *J, RecordFFData *rd)
 747 {
 748   TRef tab = J->base[0];
 749   rd->nres = 0;
 750   if (tref_istab(tab)) {
 751     if (tref_isnil(J->base[1])) {  /* Simple pop: t[#t] = nil */
 752       TRef trlen = lj_ir_call(J, IRCALL_lj_tab_len, tab);
 753       GCtab *t = tabV(&rd->argv[0]);
 754       MSize len = lj_tab_len(t);
 755       emitir(IRTGI(len ? IR_NE : IR_EQ), trlen, lj_ir_kint(J, 0));
 756       if (len) {
 757         RecordIndex ix;
 758         ix.tab = tab;
 759         ix.key = trlen;
 760         settabV(J->L, &ix.tabv, t);
 761         setintV(&ix.keyv, len);
 762         ix.idxchain = 0;
 763         if (results_wanted(J) != 0) {  /* Specialize load only if needed. */
 764           ix.val = 0;
 765           J->base[0] = lj_record_idx(J, &ix);  /* Load previous value. */
 766           rd->nres = 1;
 767           /* Assumes ix.key/ix.tab is not modified for raw lj_record_idx(). */
 768         }
 769         ix.val = TREF_NIL;
 770         lj_record_idx(J, &ix);  /* Remove value. */
 771       }
 772     } else {  /* Complex case: remove in the middle. */
 773       recff_nyiu(J);
 774     }
 775   }  /* else: Interpreter will throw. */
 776 }
 777
 778 static void LJ_FASTCALL recff_table_insert(jit_State *J, RecordFFData *rd)
 779 {
 780   RecordIndex ix;
 781   ix.tab = J->base[0];
 782   ix.val = J->base[1];
 783   rd->nres = 0;
 784   if (tref_istab(ix.tab) && ix.val) {
 785     if (!J->base[2]) {  /* Simple push: t[#t+1] = v */
 786       TRef trlen = lj_ir_call(J, IRCALL_lj_tab_len, ix.tab);
 787       GCtab *t = tabV(&rd->argv[0]);
 788       ix.key = emitir(IRTI(IR_ADD), trlen, lj_ir_kint(J, 1));
 789       settabV(J->L, &ix.tabv, t);
 790       setintV(&ix.keyv, lj_tab_len(t) + 1);
 791       ix.idxchain = 0;
 792       lj_record_idx(J, &ix);  /* Set new value. */
 793     } else {  /* Complex case: insert in the middle. */
 794       recff_nyiu(J);
 795     }
 796   }  /* else: Interpreter will throw. */
 797 }
 798
 799 /* -- I/O library fast functions ------------------------------------------ */
 800
 801 /* Get FILE* for I/O function. Any I/O error aborts recording, so there's
 802 ** no need to encode the alternate cases for any of the guards.
 803 */
 804 static TRef recff_io_fp(jit_State *J, TRef *udp, int32_t id)
 805 {
 806   TRef tr, ud, fp;
 807   if (id) {  /* io.func() */
 808     tr = lj_ir_kptr(J, &J2G(J)->gcroot[id]);
 809     ud = emitir(IRT(IR_XLOAD, IRT_UDATA), tr, 0);
 810   } else {  /* fp:method() */
 811     ud = J->base[0];
 812     if (!tref_isudata(ud))
 813       lj_trace_err(J, LJ_TRERR_BADTYPE);
 814     tr = emitir(IRT(IR_FLOAD, IRT_U8), ud, IRFL_UDATA_UDTYPE);
 815     emitir(IRTGI(IR_EQ), tr, lj_ir_kint(J, UDTYPE_IO_FILE));
 816   }
 817   *udp = ud;
 818   fp = emitir(IRT(IR_FLOAD, IRT_PTR), ud, IRFL_UDATA_FILE);
 819   emitir(IRTG(IR_NE, IRT_PTR), fp, lj_ir_knull(J, IRT_PTR));
 820   return fp;
 821 }
 822
 823 static void LJ_FASTCALL recff_io_write(jit_State *J, RecordFFData *rd)
 824 {
 825   TRef ud, fp = recff_io_fp(J, &ud, rd->data);
 826   TRef zero = lj_ir_kint(J, 0);
 827   TRef one = lj_ir_kint(J, 1);
 828   ptrdiff_t i = rd->data == 0 ? 1 : 0;
 829   for (; J->base[i]; i++) {
 830     TRef str = lj_ir_tostr(J, J->base[i]);
 831     TRef buf = emitir(IRT(IR_STRREF, IRT_P32), str, zero);
 832     TRef len = emitir(IRTI(IR_FLOAD), str, IRFL_STR_LEN);
 833     if (tref_isk(len) && IR(tref_ref(len))->i == 1) {
 834       TRef tr = emitir(IRT(IR_XLOAD, IRT_U8), buf, IRXLOAD_READONLY);
 835       tr = lj_ir_call(J, IRCALL_fputc, tr, fp);
 836       if (results_wanted(J) != 0)  /* Check result only if not ignored. */
 837         emitir(IRTGI(IR_NE), tr, lj_ir_kint(J, -1));
 838     } else {
 839       TRef tr = lj_ir_call(J, IRCALL_fwrite, buf, one, len, fp);
 840       if (results_wanted(J) != 0)  /* Check result only if not ignored. */
 841         emitir(IRTGI(IR_EQ), tr, len);
 842     }
 843   }
 844   J->base[0] = LJ_52 ? ud : TREF_TRUE;
 845 }
 846
 847 static void LJ_FASTCALL recff_io_flush(jit_State *J, RecordFFData *rd)
 848 {
 849   TRef ud, fp = recff_io_fp(J, &ud, rd->data);
 850   TRef tr = lj_ir_call(J, IRCALL_fflush, fp);
 851   if (results_wanted(J) != 0)  /* Check result only if not ignored. */
 852     emitir(IRTGI(IR_EQ), tr, lj_ir_kint(J, 0));
 853   J->base[0] = TREF_TRUE;
 854 }
 855
 856 /* -- Record calls to fast functions -------------------------------------- */
 857
 858 #include "lj_recdef.h"
 859
 860 static uint32_t recdef_lookup(GCfunc *fn)
 861 {
 862   if (fn->c.ffid < sizeof(recff_idmap)/sizeof(recff_idmap[0]))
 863     return recff_idmap[fn->c.ffid];
 864   else
 865     return 0;
 866 }
 867
 868 /* Record entry to a fast function or C function. */
 869 void lj_ffrecord_func(jit_State *J)
 870 {
 871   RecordFFData rd;
 872   uint32_t m = recdef_lookup(J->fn);
 873   rd.data = m & 0xff;
 874   rd.nres = 1;  /* Default is one result. */
 875   rd.argv = J->L->base;
 876   J->base[J->maxslot] = 0;  /* Mark end of arguments. */
 877   (recff_func[m >> 8])(J, &rd);  /* Call recff_* handler. */
 878   if (rd.nres >= 0) {
 879     if (J->postproc == LJ_POST_NONE) J->postproc = LJ_POST_FFRETRY;
 880     lj_record_ret(J, 0, rd.nres);
 881   }
 882 }
 883
 884 #undef IR
 885 #undef emitir
 886
 887 #endif