mirror of
https://github.com/lua/lua
synced 2024-11-22 12:51:30 +03:00
4d5de1c1fb
When creating code for a jump on a 'not' condition, the code generator was removing an instruction (the OP_NOT) without adjusting its corresponding line information. This fix also added tests for this case and extra functionality in the test library to debug line info. structures.
1697 lines
47 KiB
C
1697 lines
47 KiB
C
/*
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** $Id: lcode.c $
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** Code generator for Lua
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** See Copyright Notice in lua.h
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*/
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#define lcode_c
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#define LUA_CORE
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#include "lprefix.h"
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#include <limits.h>
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#include <math.h>
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#include <stdlib.h>
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#include "lua.h"
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#include "lcode.h"
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#include "ldebug.h"
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#include "ldo.h"
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#include "lgc.h"
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#include "llex.h"
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#include "lmem.h"
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#include "lobject.h"
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#include "lopcodes.h"
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#include "lparser.h"
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#include "lstring.h"
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#include "ltable.h"
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#include "lvm.h"
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/* Maximum number of registers in a Lua function (must fit in 8 bits) */
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#define MAXREGS 255
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#define hasjumps(e) ((e)->t != (e)->f)
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static int codesJ (FuncState *fs, OpCode o, int sj, int k);
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/* semantic error */
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l_noret luaK_semerror (LexState *ls, const char *msg) {
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ls->t.token = 0; /* remove "near <token>" from final message */
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luaX_syntaxerror(ls, msg);
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}
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/*
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** If expression is a numeric constant, fills 'v' with its value
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** and returns 1. Otherwise, returns 0.
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*/
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static int tonumeral(const expdesc *e, TValue *v) {
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if (hasjumps(e))
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return 0; /* not a numeral */
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switch (e->k) {
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case VKINT:
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if (v) setivalue(v, e->u.ival);
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return 1;
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case VKFLT:
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if (v) setfltvalue(v, e->u.nval);
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return 1;
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default: return 0;
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}
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}
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/*
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** Return the previous instruction of the current code. If there
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** may be a jump target between the current instruction and the
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** previous one, return an invalid instruction (to avoid wrong
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** optimizations).
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*/
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static Instruction *previousinstruction (FuncState *fs) {
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static const Instruction invalidinstruction = -1;
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if (fs->pc > fs->lasttarget)
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return &fs->f->code[fs->pc - 1]; /* previous instruction */
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else
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return cast(Instruction*, &invalidinstruction);
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}
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/*
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** Create a OP_LOADNIL instruction, but try to optimize: if the previous
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** instruction is also OP_LOADNIL and ranges are compatible, adjust
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** range of previous instruction instead of emitting a new one. (For
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** instance, 'local a; local b' will generate a single opcode.)
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*/
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void luaK_nil (FuncState *fs, int from, int n) {
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int l = from + n - 1; /* last register to set nil */
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Instruction *previous = previousinstruction(fs);
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if (GET_OPCODE(*previous) == OP_LOADNIL) { /* previous is LOADNIL? */
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int pfrom = GETARG_A(*previous); /* get previous range */
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int pl = pfrom + GETARG_B(*previous);
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if ((pfrom <= from && from <= pl + 1) ||
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(from <= pfrom && pfrom <= l + 1)) { /* can connect both? */
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if (pfrom < from) from = pfrom; /* from = min(from, pfrom) */
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if (pl > l) l = pl; /* l = max(l, pl) */
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SETARG_A(*previous, from);
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SETARG_B(*previous, l - from);
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return;
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} /* else go through */
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}
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luaK_codeABC(fs, OP_LOADNIL, from, n - 1, 0); /* else no optimization */
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}
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/*
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** Gets the destination address of a jump instruction. Used to traverse
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** a list of jumps.
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*/
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static int getjump (FuncState *fs, int pc) {
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int offset = GETARG_sJ(fs->f->code[pc]);
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if (offset == NO_JUMP) /* point to itself represents end of list */
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return NO_JUMP; /* end of list */
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else
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return (pc+1)+offset; /* turn offset into absolute position */
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}
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/*
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** Fix jump instruction at position 'pc' to jump to 'dest'.
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** (Jump addresses are relative in Lua)
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*/
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static void fixjump (FuncState *fs, int pc, int dest) {
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Instruction *jmp = &fs->f->code[pc];
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int offset = dest - (pc + 1);
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lua_assert(dest != NO_JUMP);
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if (!(-OFFSET_sJ <= offset && offset <= MAXARG_sJ - OFFSET_sJ))
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luaX_syntaxerror(fs->ls, "control structure too long");
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lua_assert(GET_OPCODE(*jmp) == OP_JMP);
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SETARG_sJ(*jmp, offset);
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}
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/*
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** Concatenate jump-list 'l2' into jump-list 'l1'
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*/
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void luaK_concat (FuncState *fs, int *l1, int l2) {
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if (l2 == NO_JUMP) return; /* nothing to concatenate? */
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else if (*l1 == NO_JUMP) /* no original list? */
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*l1 = l2; /* 'l1' points to 'l2' */
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else {
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int list = *l1;
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int next;
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while ((next = getjump(fs, list)) != NO_JUMP) /* find last element */
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list = next;
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fixjump(fs, list, l2); /* last element links to 'l2' */
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}
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}
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/*
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** Create a jump instruction and return its position, so its destination
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** can be fixed later (with 'fixjump').
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*/
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int luaK_jump (FuncState *fs) {
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return codesJ(fs, OP_JMP, NO_JUMP, 0);
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}
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/*
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** Code a 'return' instruction
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*/
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void luaK_ret (FuncState *fs, int first, int nret) {
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OpCode op;
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switch (nret) {
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case 0: op = OP_RETURN0; break;
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case 1: op = OP_RETURN1; break;
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default: op = OP_RETURN; break;
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}
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luaK_codeABC(fs, op, first, nret + 1, 0);
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}
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/*
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** Code a "conditional jump", that is, a test or comparison opcode
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** followed by a jump. Return jump position.
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*/
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static int condjump (FuncState *fs, OpCode op, int A, int B, int k) {
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luaK_codeABCk(fs, op, A, B, 0, k);
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return luaK_jump(fs);
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}
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/*
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** returns current 'pc' and marks it as a jump target (to avoid wrong
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** optimizations with consecutive instructions not in the same basic block).
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*/
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int luaK_getlabel (FuncState *fs) {
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fs->lasttarget = fs->pc;
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return fs->pc;
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}
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/*
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** Returns the position of the instruction "controlling" a given
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** jump (that is, its condition), or the jump itself if it is
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** unconditional.
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*/
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static Instruction *getjumpcontrol (FuncState *fs, int pc) {
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Instruction *pi = &fs->f->code[pc];
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if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1))))
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return pi-1;
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else
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return pi;
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}
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/*
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** Patch destination register for a TESTSET instruction.
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** If instruction in position 'node' is not a TESTSET, return 0 ("fails").
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** Otherwise, if 'reg' is not 'NO_REG', set it as the destination
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** register. Otherwise, change instruction to a simple 'TEST' (produces
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** no register value)
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*/
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static int patchtestreg (FuncState *fs, int node, int reg) {
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Instruction *i = getjumpcontrol(fs, node);
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if (GET_OPCODE(*i) != OP_TESTSET)
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return 0; /* cannot patch other instructions */
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if (reg != NO_REG && reg != GETARG_B(*i))
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SETARG_A(*i, reg);
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else {
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/* no register to put value or register already has the value;
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change instruction to simple test */
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*i = CREATE_ABCk(OP_TEST, GETARG_B(*i), 0, 0, GETARG_k(*i));
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}
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return 1;
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}
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/*
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** Traverse a list of tests ensuring no one produces a value
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*/
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static void removevalues (FuncState *fs, int list) {
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for (; list != NO_JUMP; list = getjump(fs, list))
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patchtestreg(fs, list, NO_REG);
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}
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/*
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** Traverse a list of tests, patching their destination address and
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** registers: tests producing values jump to 'vtarget' (and put their
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** values in 'reg'), other tests jump to 'dtarget'.
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*/
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static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
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int dtarget) {
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while (list != NO_JUMP) {
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int next = getjump(fs, list);
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if (patchtestreg(fs, list, reg))
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fixjump(fs, list, vtarget);
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else
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fixjump(fs, list, dtarget); /* jump to default target */
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list = next;
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}
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}
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/*
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** Path all jumps in 'list' to jump to 'target'.
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** (The assert means that we cannot fix a jump to a forward address
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** because we only know addresses once code is generated.)
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*/
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void luaK_patchlist (FuncState *fs, int list, int target) {
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lua_assert(target <= fs->pc);
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patchlistaux(fs, list, target, NO_REG, target);
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}
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void luaK_patchtohere (FuncState *fs, int list) {
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int hr = luaK_getlabel(fs); /* mark "here" as a jump target */
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luaK_patchlist(fs, list, hr);
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}
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/*
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** Correct a jump list to jump to 'target'. If 'hasclose' is true,
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** 'target' contains an OP_CLOSE instruction (see first assert).
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** Only the jumps with ('m' == true) need that close; other jumps
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** avoid it jumping to the next instruction.
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*/
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void luaK_patchgoto (FuncState *fs, int list, int target, int hasclose) {
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lua_assert(!hasclose || GET_OPCODE(fs->f->code[target]) == OP_CLOSE);
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while (list != NO_JUMP) {
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int next = getjump(fs, list);
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lua_assert(!GETARG_m(fs->f->code[list]) || hasclose);
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patchtestreg(fs, list, NO_REG); /* do not generate values */
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if (!hasclose || GETARG_m(fs->f->code[list]))
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fixjump(fs, list, target);
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else /* there is a CLOSE instruction but jump does not need it */
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fixjump(fs, list, target + 1); /* avoid CLOSE instruction */
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list = next;
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}
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}
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/*
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** Mark (using the 'm' arg) all jumps in 'list' to close upvalues. Mark
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** will instruct 'luaK_patchgoto' to make these jumps go to OP_CLOSE
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** instructions.
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*/
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void luaK_patchclose (FuncState *fs, int list) {
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for (; list != NO_JUMP; list = getjump(fs, list)) {
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lua_assert(GET_OPCODE(fs->f->code[list]) == OP_JMP);
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SETARG_m(fs->f->code[list], 1);
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}
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}
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/*
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** MAXimum number of successive Instructions WiTHout ABSolute line
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** information.
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*/
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#if !defined(MAXIWTHABS)
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#define MAXIWTHABS 120
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#endif
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/* limit for difference between lines in relative line info. */
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#define LIMLINEDIFF 0x80
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/*
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** Save line info for a new instruction. If difference from last line
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** does not fit in a byte, of after that many instructions, save a new
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** absolute line info; (in that case, the special value 'ABSLINEINFO'
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** in 'lineinfo' signals the existence of this absolute information.)
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** Otherwise, store the difference from last line in 'lineinfo'.
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*/
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static void savelineinfo (FuncState *fs, Proto *f, int line) {
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int linedif = line - fs->previousline;
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int pc = fs->pc - 1; /* last instruction coded */
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if (abs(linedif) >= LIMLINEDIFF || fs->iwthabs++ > MAXIWTHABS) {
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luaM_growvector(fs->ls->L, f->abslineinfo, fs->nabslineinfo,
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f->sizeabslineinfo, AbsLineInfo, MAX_INT, "lines");
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f->abslineinfo[fs->nabslineinfo].pc = pc;
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f->abslineinfo[fs->nabslineinfo++].line = line;
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linedif = ABSLINEINFO; /* signal that there is absolute information */
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fs->iwthabs = 0; /* restart counter */
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}
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luaM_growvector(fs->ls->L, f->lineinfo, pc, f->sizelineinfo, ls_byte,
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MAX_INT, "opcodes");
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f->lineinfo[pc] = linedif;
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fs->previousline = line; /* last line saved */
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}
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/*
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** Remove line information from the last instruction.
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** If line information for that instruction is absolute, set 'iwthabs'
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** above its max to force the new (replacing) instruction to have
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** absolute line info, too.
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*/
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static void removelastlineinfo (FuncState *fs) {
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Proto *f = fs->f;
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int pc = fs->pc - 1; /* last instruction coded */
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if (f->lineinfo[pc] != ABSLINEINFO) { /* relative line info? */
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fs->previousline -= f->lineinfo[pc]; /* last line saved */
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fs->iwthabs--;
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}
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else { /* absolute line information */
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fs->nabslineinfo--; /* remove it */
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lua_assert(f->abslineinfo[fs->nabslineinfo].pc = pc);
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fs->iwthabs = MAXIWTHABS + 1; /* force next line info to be absolute */
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}
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}
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/*
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** Remove the last instruction created, correcting line information
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** accordingly.
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*/
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static void removelastinstruction (FuncState *fs) {
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removelastlineinfo(fs);
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fs->pc--;
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}
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/*
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** Emit instruction 'i', checking for array sizes and saving also its
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** line information. Return 'i' position.
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*/
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static int luaK_code (FuncState *fs, Instruction i) {
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Proto *f = fs->f;
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/* put new instruction in code array */
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luaM_growvector(fs->ls->L, f->code, fs->pc, f->sizecode, Instruction,
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MAX_INT, "opcodes");
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f->code[fs->pc++] = i;
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savelineinfo(fs, f, fs->ls->lastline);
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return fs->pc - 1; /* index of new instruction */
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}
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/*
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** Format and emit an 'iABC' instruction. (Assertions check consistency
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** of parameters versus opcode.)
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*/
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int luaK_codeABCk (FuncState *fs, OpCode o, int a, int b, int c, int k) {
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lua_assert(getOpMode(o) == iABC);
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lua_assert(a <= MAXARG_A && b <= MAXARG_B &&
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c <= MAXARG_C && (k & ~1) == 0);
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return luaK_code(fs, CREATE_ABCk(o, a, b, c, k));
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}
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#define codeABsC(fs,o,a,b,c,k) luaK_codeABCk(fs,o,a,b,((c) + OFFSET_sC),k)
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/*
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** Format and emit an 'iABx' instruction.
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*/
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int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
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lua_assert(getOpMode(o) == iABx);
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lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx);
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return luaK_code(fs, CREATE_ABx(o, a, bc));
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}
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/*
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** Format and emit an 'iAsBx' instruction.
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*/
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int luaK_codeAsBx (FuncState *fs, OpCode o, int a, int bc) {
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unsigned int b = bc + OFFSET_sBx;
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lua_assert(getOpMode(o) == iAsBx);
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lua_assert(a <= MAXARG_A && b <= MAXARG_Bx);
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return luaK_code(fs, CREATE_ABx(o, a, b));
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}
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/*
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** Format and emit an 'isJ' instruction.
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*/
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static int codesJ (FuncState *fs, OpCode o, int sj, int k) {
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unsigned int j = sj + OFFSET_sJ;
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lua_assert(getOpMode(o) == isJ);
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lua_assert(j <= MAXARG_sJ && (k & ~1) == 0);
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return luaK_code(fs, CREATE_sJ(o, j, k));
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}
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/*
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** Emit an "extra argument" instruction (format 'iAx')
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*/
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static int codeextraarg (FuncState *fs, int a) {
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lua_assert(a <= MAXARG_Ax);
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return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a));
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}
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/*
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** Emit a "load constant" instruction, using either 'OP_LOADK'
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** (if constant index 'k' fits in 18 bits) or an 'OP_LOADKX'
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** instruction with "extra argument".
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*/
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static int luaK_codek (FuncState *fs, int reg, int k) {
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if (k <= MAXARG_Bx)
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return luaK_codeABx(fs, OP_LOADK, reg, k);
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else {
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int p = luaK_codeABx(fs, OP_LOADKX, reg, 0);
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codeextraarg(fs, k);
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return p;
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}
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}
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/*
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** Check register-stack level, keeping track of its maximum size
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** in field 'maxstacksize'
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*/
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void luaK_checkstack (FuncState *fs, int n) {
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int newstack = fs->freereg + n;
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if (newstack > fs->f->maxstacksize) {
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if (newstack >= MAXREGS)
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luaX_syntaxerror(fs->ls,
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"function or expression needs too many registers");
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fs->f->maxstacksize = cast_byte(newstack);
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}
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}
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/*
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** Reserve 'n' registers in register stack
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*/
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void luaK_reserveregs (FuncState *fs, int n) {
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luaK_checkstack(fs, n);
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fs->freereg += n;
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}
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/*
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** Free register 'reg', if it is neither a constant index nor
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** a local variable.
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)
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*/
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static void freereg (FuncState *fs, int reg) {
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if (reg >= fs->nactvar) {
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fs->freereg--;
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lua_assert(reg == fs->freereg);
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}
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}
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/*
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** Free two registers in proper order
|
|
*/
|
|
static void freeregs (FuncState *fs, int r1, int r2) {
|
|
if (r1 > r2) {
|
|
freereg(fs, r1);
|
|
freereg(fs, r2);
|
|
}
|
|
else {
|
|
freereg(fs, r2);
|
|
freereg(fs, r1);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Free register used by expression 'e' (if any)
|
|
*/
|
|
static void freeexp (FuncState *fs, expdesc *e) {
|
|
if (e->k == VNONRELOC)
|
|
freereg(fs, e->u.info);
|
|
}
|
|
|
|
|
|
/*
|
|
** Free registers used by expressions 'e1' and 'e2' (if any) in proper
|
|
** order.
|
|
*/
|
|
static void freeexps (FuncState *fs, expdesc *e1, expdesc *e2) {
|
|
int r1 = (e1->k == VNONRELOC) ? e1->u.info : -1;
|
|
int r2 = (e2->k == VNONRELOC) ? e2->u.info : -1;
|
|
freeregs(fs, r1, r2);
|
|
}
|
|
|
|
|
|
/*
|
|
** Add constant 'v' to prototype's list of constants (field 'k').
|
|
** Use scanner's table to cache position of constants in constant list
|
|
** and try to reuse constants. Because some values should not be used
|
|
** as keys (nil cannot be a key, integer keys can collapse with float
|
|
** keys), the caller must provide a useful 'key' for indexing the cache.
|
|
*/
|
|
static int addk (FuncState *fs, TValue *key, TValue *v) {
|
|
lua_State *L = fs->ls->L;
|
|
Proto *f = fs->f;
|
|
TValue *idx = luaH_set(L, fs->ls->h, key); /* index scanner table */
|
|
int k, oldsize;
|
|
if (ttisinteger(idx)) { /* is there an index there? */
|
|
k = cast_int(ivalue(idx));
|
|
/* correct value? (warning: must distinguish floats from integers!) */
|
|
if (k < fs->nk && ttypetag(&f->k[k]) == ttypetag(v) &&
|
|
luaV_rawequalobj(&f->k[k], v))
|
|
return k; /* reuse index */
|
|
}
|
|
/* constant not found; create a new entry */
|
|
oldsize = f->sizek;
|
|
k = fs->nk;
|
|
/* numerical value does not need GC barrier;
|
|
table has no metatable, so it does not need to invalidate cache */
|
|
setivalue(idx, k);
|
|
luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants");
|
|
while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
|
|
setobj(L, &f->k[k], v);
|
|
fs->nk++;
|
|
luaC_barrier(L, f, v);
|
|
return k;
|
|
}
|
|
|
|
|
|
/*
|
|
** Add a string to list of constants and return its index.
|
|
*/
|
|
int luaK_stringK (FuncState *fs, TString *s) {
|
|
TValue o;
|
|
setsvalue(fs->ls->L, &o, s);
|
|
return addk(fs, &o, &o); /* use string itself as key */
|
|
}
|
|
|
|
|
|
/*
|
|
** Add an integer to list of constants and return its index.
|
|
** Integers use userdata as keys to avoid collision with floats with
|
|
** same value; conversion to 'void*' is used only for hashing, so there
|
|
** are no "precision" problems.
|
|
*/
|
|
static int luaK_intK (FuncState *fs, lua_Integer n) {
|
|
TValue k, o;
|
|
setpvalue(&k, cast_voidp(cast_sizet(n)));
|
|
setivalue(&o, n);
|
|
return addk(fs, &k, &o);
|
|
}
|
|
|
|
/*
|
|
** Add a float to list of constants and return its index.
|
|
*/
|
|
static int luaK_numberK (FuncState *fs, lua_Number r) {
|
|
TValue o;
|
|
setfltvalue(&o, r);
|
|
return addk(fs, &o, &o); /* use number itself as key */
|
|
}
|
|
|
|
|
|
/*
|
|
** Add a boolean to list of constants and return its index.
|
|
*/
|
|
static int boolK (FuncState *fs, int b) {
|
|
TValue o;
|
|
setbvalue(&o, b);
|
|
return addk(fs, &o, &o); /* use boolean itself as key */
|
|
}
|
|
|
|
|
|
/*
|
|
** Add nil to list of constants and return its index.
|
|
*/
|
|
static int nilK (FuncState *fs) {
|
|
TValue k, v;
|
|
setnilvalue(&v);
|
|
/* cannot use nil as key; instead use table itself to represent nil */
|
|
sethvalue(fs->ls->L, &k, fs->ls->h);
|
|
return addk(fs, &k, &v);
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether 'i' can be stored in an 'sC' operand.
|
|
** Equivalent to (0 <= i + OFFSET_sC && i + OFFSET_sC <= MAXARG_C)
|
|
** but without risk of overflows in the addition.
|
|
*/
|
|
static int fitsC (lua_Integer i) {
|
|
return (-OFFSET_sC <= i && i <= MAXARG_C - OFFSET_sC);
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether 'i' can be stored in an 'sBx' operand.
|
|
*/
|
|
static int fitsBx (lua_Integer i) {
|
|
return (-OFFSET_sBx <= i && i <= MAXARG_Bx - OFFSET_sBx);
|
|
}
|
|
|
|
|
|
void luaK_int (FuncState *fs, int reg, lua_Integer i) {
|
|
if (fitsBx(i))
|
|
luaK_codeAsBx(fs, OP_LOADI, reg, cast_int(i));
|
|
else
|
|
luaK_codek(fs, reg, luaK_intK(fs, i));
|
|
}
|
|
|
|
|
|
static int floatI (lua_Number f, lua_Integer *fi) {
|
|
return (luaV_flttointeger(f, fi, 0) && fitsBx(*fi));
|
|
}
|
|
|
|
|
|
static void luaK_float (FuncState *fs, int reg, lua_Number f) {
|
|
lua_Integer fi;
|
|
if (floatI(f, &fi))
|
|
luaK_codeAsBx(fs, OP_LOADF, reg, cast_int(fi));
|
|
else
|
|
luaK_codek(fs, reg, luaK_numberK(fs, f));
|
|
}
|
|
|
|
|
|
/*
|
|
** Fix an expression to return the number of results 'nresults'.
|
|
** Either 'e' is a multi-ret expression (function call or vararg)
|
|
** or 'nresults' is LUA_MULTRET (as any expression can satisfy that).
|
|
*/
|
|
void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
|
|
Instruction *pc = &getinstruction(fs, e);
|
|
if (e->k == VCALL) /* expression is an open function call? */
|
|
SETARG_C(*pc, nresults + 1);
|
|
else if (e->k == VVARARG) {
|
|
SETARG_C(*pc, nresults + 1);
|
|
SETARG_A(*pc, fs->freereg);
|
|
luaK_reserveregs(fs, 1);
|
|
}
|
|
else lua_assert(nresults == LUA_MULTRET);
|
|
}
|
|
|
|
|
|
/*
|
|
** Fix an expression to return one result.
|
|
** If expression is not a multi-ret expression (function call or
|
|
** vararg), it already returns one result, so nothing needs to be done.
|
|
** Function calls become VNONRELOC expressions (as its result comes
|
|
** fixed in the base register of the call), while vararg expressions
|
|
** become VRELOC (as OP_VARARG puts its results where it wants).
|
|
** (Calls are created returning one result, so that does not need
|
|
** to be fixed.)
|
|
*/
|
|
void luaK_setoneret (FuncState *fs, expdesc *e) {
|
|
if (e->k == VCALL) { /* expression is an open function call? */
|
|
/* already returns 1 value */
|
|
lua_assert(GETARG_C(getinstruction(fs, e)) == 2);
|
|
e->k = VNONRELOC; /* result has fixed position */
|
|
e->u.info = GETARG_A(getinstruction(fs, e));
|
|
}
|
|
else if (e->k == VVARARG) {
|
|
SETARG_C(getinstruction(fs, e), 2);
|
|
e->k = VRELOC; /* can relocate its simple result */
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensure that expression 'e' is not a variable.
|
|
** (Expression still may have jump lists.)
|
|
*/
|
|
void luaK_dischargevars (FuncState *fs, expdesc *e) {
|
|
switch (e->k) {
|
|
case VLOCAL: { /* already in a register */
|
|
e->k = VNONRELOC; /* becomes a non-relocatable value */
|
|
break;
|
|
}
|
|
case VUPVAL: { /* move value to some (pending) register */
|
|
e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
|
|
e->k = VRELOC;
|
|
break;
|
|
}
|
|
case VINDEXUP: {
|
|
e->u.info = luaK_codeABC(fs, OP_GETTABUP, 0, e->u.ind.t, e->u.ind.idx);
|
|
e->k = VRELOC;
|
|
break;
|
|
}
|
|
case VINDEXI: {
|
|
freereg(fs, e->u.ind.t);
|
|
e->u.info = luaK_codeABC(fs, OP_GETI, 0, e->u.ind.t, e->u.ind.idx);
|
|
e->k = VRELOC;
|
|
break;
|
|
}
|
|
case VINDEXSTR: {
|
|
freereg(fs, e->u.ind.t);
|
|
e->u.info = luaK_codeABC(fs, OP_GETFIELD, 0, e->u.ind.t, e->u.ind.idx);
|
|
e->k = VRELOC;
|
|
break;
|
|
}
|
|
case VINDEXED: {
|
|
freeregs(fs, e->u.ind.t, e->u.ind.idx);
|
|
e->u.info = luaK_codeABC(fs, OP_GETTABLE, 0, e->u.ind.t, e->u.ind.idx);
|
|
e->k = VRELOC;
|
|
break;
|
|
}
|
|
case VVARARG: case VCALL: {
|
|
luaK_setoneret(fs, e);
|
|
break;
|
|
}
|
|
default: break; /* there is one value available (somewhere) */
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures expression value is in register 'reg' (and therefore
|
|
** 'e' will become a non-relocatable expression).
|
|
** (Expression still may have jump lists.)
|
|
*/
|
|
static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
|
|
luaK_dischargevars(fs, e);
|
|
switch (e->k) {
|
|
case VNIL: {
|
|
luaK_nil(fs, reg, 1);
|
|
break;
|
|
}
|
|
case VFALSE: case VTRUE: {
|
|
luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
|
|
break;
|
|
}
|
|
case VK: {
|
|
luaK_codek(fs, reg, e->u.info);
|
|
break;
|
|
}
|
|
case VKFLT: {
|
|
luaK_float(fs, reg, e->u.nval);
|
|
break;
|
|
}
|
|
case VKINT: {
|
|
luaK_int(fs, reg, e->u.ival);
|
|
break;
|
|
}
|
|
case VRELOC: {
|
|
Instruction *pc = &getinstruction(fs, e);
|
|
SETARG_A(*pc, reg); /* instruction will put result in 'reg' */
|
|
break;
|
|
}
|
|
case VNONRELOC: {
|
|
if (reg != e->u.info)
|
|
luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
|
|
break;
|
|
}
|
|
default: {
|
|
lua_assert(e->k == VJMP);
|
|
return; /* nothing to do... */
|
|
}
|
|
}
|
|
e->u.info = reg;
|
|
e->k = VNONRELOC;
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures expression value is in any register.
|
|
** (Expression still may have jump lists.)
|
|
*/
|
|
static void discharge2anyreg (FuncState *fs, expdesc *e) {
|
|
if (e->k != VNONRELOC) { /* no fixed register yet? */
|
|
luaK_reserveregs(fs, 1); /* get a register */
|
|
discharge2reg(fs, e, fs->freereg-1); /* put value there */
|
|
}
|
|
}
|
|
|
|
|
|
static int code_loadbool (FuncState *fs, int A, int b, int jump) {
|
|
luaK_getlabel(fs); /* those instructions may be jump targets */
|
|
return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump);
|
|
}
|
|
|
|
|
|
/*
|
|
** check whether list has any jump that do not produce a value
|
|
** or produce an inverted value
|
|
*/
|
|
static int need_value (FuncState *fs, int list) {
|
|
for (; list != NO_JUMP; list = getjump(fs, list)) {
|
|
Instruction i = *getjumpcontrol(fs, list);
|
|
if (GET_OPCODE(i) != OP_TESTSET) return 1;
|
|
}
|
|
return 0; /* not found */
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures final expression result (which includes results from its
|
|
** jump ** lists) is in register 'reg'.
|
|
** If expression has jumps, need to patch these jumps either to
|
|
** its final position or to "load" instructions (for those tests
|
|
** that do not produce values).
|
|
*/
|
|
static void exp2reg (FuncState *fs, expdesc *e, int reg) {
|
|
discharge2reg(fs, e, reg);
|
|
if (e->k == VJMP) /* expression itself is a test? */
|
|
luaK_concat(fs, &e->t, e->u.info); /* put this jump in 't' list */
|
|
if (hasjumps(e)) {
|
|
int final; /* position after whole expression */
|
|
int p_f = NO_JUMP; /* position of an eventual LOAD false */
|
|
int p_t = NO_JUMP; /* position of an eventual LOAD true */
|
|
if (need_value(fs, e->t) || need_value(fs, e->f)) {
|
|
int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs);
|
|
p_f = code_loadbool(fs, reg, 0, 1);
|
|
p_t = code_loadbool(fs, reg, 1, 0);
|
|
luaK_patchtohere(fs, fj);
|
|
}
|
|
final = luaK_getlabel(fs);
|
|
patchlistaux(fs, e->f, final, reg, p_f);
|
|
patchlistaux(fs, e->t, final, reg, p_t);
|
|
}
|
|
e->f = e->t = NO_JUMP;
|
|
e->u.info = reg;
|
|
e->k = VNONRELOC;
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures final expression result is in next available register.
|
|
*/
|
|
void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
|
|
luaK_dischargevars(fs, e);
|
|
freeexp(fs, e);
|
|
luaK_reserveregs(fs, 1);
|
|
exp2reg(fs, e, fs->freereg - 1);
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures final expression result is in some (any) register
|
|
** and return that register.
|
|
*/
|
|
int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
|
|
luaK_dischargevars(fs, e);
|
|
if (e->k == VNONRELOC) { /* expression already has a register? */
|
|
if (!hasjumps(e)) /* no jumps? */
|
|
return e->u.info; /* result is already in a register */
|
|
if (e->u.info >= fs->nactvar) { /* reg. is not a local? */
|
|
exp2reg(fs, e, e->u.info); /* put final result in it */
|
|
return e->u.info;
|
|
}
|
|
}
|
|
luaK_exp2nextreg(fs, e); /* otherwise, use next available register */
|
|
return e->u.info;
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures final expression result is either in a register
|
|
** or in an upvalue.
|
|
*/
|
|
void luaK_exp2anyregup (FuncState *fs, expdesc *e) {
|
|
if (e->k != VUPVAL || hasjumps(e))
|
|
luaK_exp2anyreg(fs, e);
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures final expression result is either in a register
|
|
** or it is a constant.
|
|
*/
|
|
void luaK_exp2val (FuncState *fs, expdesc *e) {
|
|
if (hasjumps(e))
|
|
luaK_exp2anyreg(fs, e);
|
|
else
|
|
luaK_dischargevars(fs, e);
|
|
}
|
|
|
|
|
|
/*
|
|
** Ensures final expression result is in a valid R/K index
|
|
** (that is, it is either in a register or in 'k' with an index
|
|
** in the range of R/K indices).
|
|
** Returns 1 if expression is K, 0 otherwise.
|
|
*/
|
|
int luaK_exp2RK (FuncState *fs, expdesc *e) {
|
|
luaK_exp2val(fs, e);
|
|
switch (e->k) { /* move constants to 'k' */
|
|
case VTRUE: e->u.info = boolK(fs, 1); goto vk;
|
|
case VFALSE: e->u.info = boolK(fs, 0); goto vk;
|
|
case VNIL: e->u.info = nilK(fs); goto vk;
|
|
case VKINT: e->u.info = luaK_intK(fs, e->u.ival); goto vk;
|
|
case VKFLT: e->u.info = luaK_numberK(fs, e->u.nval); goto vk;
|
|
case VK:
|
|
vk:
|
|
e->k = VK;
|
|
if (e->u.info <= MAXINDEXRK) /* constant fits in 'argC'? */
|
|
return 1;
|
|
else break;
|
|
default: break;
|
|
}
|
|
/* not a constant in the right range: put it in a register */
|
|
luaK_exp2anyreg(fs, e);
|
|
return 0;
|
|
}
|
|
|
|
|
|
static void codeABRK (FuncState *fs, OpCode o, int a, int b,
|
|
expdesc *ec) {
|
|
int k = luaK_exp2RK(fs, ec);
|
|
luaK_codeABCk(fs, o, a, b, ec->u.info, k);
|
|
}
|
|
|
|
|
|
/*
|
|
** Generate code to store result of expression 'ex' into variable 'var'.
|
|
*/
|
|
void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
|
|
switch (var->k) {
|
|
case VLOCAL: {
|
|
freeexp(fs, ex);
|
|
exp2reg(fs, ex, var->u.info); /* compute 'ex' into proper place */
|
|
return;
|
|
}
|
|
case VUPVAL: {
|
|
int e = luaK_exp2anyreg(fs, ex);
|
|
luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
|
|
break;
|
|
}
|
|
case VINDEXUP: {
|
|
codeABRK(fs, OP_SETTABUP, var->u.ind.t, var->u.ind.idx, ex);
|
|
break;
|
|
}
|
|
case VINDEXI: {
|
|
codeABRK(fs, OP_SETI, var->u.ind.t, var->u.ind.idx, ex);
|
|
break;
|
|
}
|
|
case VINDEXSTR: {
|
|
codeABRK(fs, OP_SETFIELD, var->u.ind.t, var->u.ind.idx, ex);
|
|
break;
|
|
}
|
|
case VINDEXED: {
|
|
codeABRK(fs, OP_SETTABLE, var->u.ind.t, var->u.ind.idx, ex);
|
|
break;
|
|
}
|
|
default: lua_assert(0); /* invalid var kind to store */
|
|
}
|
|
freeexp(fs, ex);
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit SELF instruction (convert expression 'e' into 'e:key(e,').
|
|
*/
|
|
void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
|
|
int ereg;
|
|
luaK_exp2anyreg(fs, e);
|
|
ereg = e->u.info; /* register where 'e' was placed */
|
|
freeexp(fs, e);
|
|
e->u.info = fs->freereg; /* base register for op_self */
|
|
e->k = VNONRELOC; /* self expression has a fixed register */
|
|
luaK_reserveregs(fs, 2); /* function and 'self' produced by op_self */
|
|
codeABRK(fs, OP_SELF, e->u.info, ereg, key);
|
|
freeexp(fs, key);
|
|
}
|
|
|
|
|
|
/*
|
|
** Negate condition 'e' (where 'e' is a comparison).
|
|
*/
|
|
static void negatecondition (FuncState *fs, expdesc *e) {
|
|
Instruction *pc = getjumpcontrol(fs, e->u.info);
|
|
lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
|
|
GET_OPCODE(*pc) != OP_TEST);
|
|
SETARG_k(*pc, (GETARG_k(*pc) ^ 1));
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit instruction to jump if 'e' is 'cond' (that is, if 'cond'
|
|
** is true, code will jump if 'e' is true.) Return jump position.
|
|
** Optimize when 'e' is 'not' something, inverting the condition
|
|
** and removing the 'not'.
|
|
*/
|
|
static int jumponcond (FuncState *fs, expdesc *e, int cond) {
|
|
if (e->k == VRELOC) {
|
|
Instruction ie = getinstruction(fs, e);
|
|
if (GET_OPCODE(ie) == OP_NOT) {
|
|
removelastinstruction(fs); /* remove previous OP_NOT */
|
|
return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond);
|
|
}
|
|
/* else go through */
|
|
}
|
|
discharge2anyreg(fs, e);
|
|
freeexp(fs, e);
|
|
return condjump(fs, OP_TESTSET, NO_REG, e->u.info, cond);
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit code to go through if 'e' is true, jump otherwise.
|
|
*/
|
|
void luaK_goiftrue (FuncState *fs, expdesc *e) {
|
|
int pc; /* pc of new jump */
|
|
luaK_dischargevars(fs, e);
|
|
switch (e->k) {
|
|
case VJMP: { /* condition? */
|
|
negatecondition(fs, e); /* jump when it is false */
|
|
pc = e->u.info; /* save jump position */
|
|
break;
|
|
}
|
|
case VK: case VKFLT: case VKINT: case VTRUE: {
|
|
pc = NO_JUMP; /* always true; do nothing */
|
|
break;
|
|
}
|
|
default: {
|
|
pc = jumponcond(fs, e, 0); /* jump when false */
|
|
break;
|
|
}
|
|
}
|
|
luaK_concat(fs, &e->f, pc); /* insert new jump in false list */
|
|
luaK_patchtohere(fs, e->t); /* true list jumps to here (to go through) */
|
|
e->t = NO_JUMP;
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit code to go through if 'e' is false, jump otherwise.
|
|
*/
|
|
void luaK_goiffalse (FuncState *fs, expdesc *e) {
|
|
int pc; /* pc of new jump */
|
|
luaK_dischargevars(fs, e);
|
|
switch (e->k) {
|
|
case VJMP: {
|
|
pc = e->u.info; /* already jump if true */
|
|
break;
|
|
}
|
|
case VNIL: case VFALSE: {
|
|
pc = NO_JUMP; /* always false; do nothing */
|
|
break;
|
|
}
|
|
default: {
|
|
pc = jumponcond(fs, e, 1); /* jump if true */
|
|
break;
|
|
}
|
|
}
|
|
luaK_concat(fs, &e->t, pc); /* insert new jump in 't' list */
|
|
luaK_patchtohere(fs, e->f); /* false list jumps to here (to go through) */
|
|
e->f = NO_JUMP;
|
|
}
|
|
|
|
|
|
/*
|
|
** Code 'not e', doing constant folding.
|
|
*/
|
|
static void codenot (FuncState *fs, expdesc *e) {
|
|
luaK_dischargevars(fs, e);
|
|
switch (e->k) {
|
|
case VNIL: case VFALSE: {
|
|
e->k = VTRUE; /* true == not nil == not false */
|
|
break;
|
|
}
|
|
case VK: case VKFLT: case VKINT: case VTRUE: {
|
|
e->k = VFALSE; /* false == not "x" == not 0.5 == not 1 == not true */
|
|
break;
|
|
}
|
|
case VJMP: {
|
|
negatecondition(fs, e);
|
|
break;
|
|
}
|
|
case VRELOC:
|
|
case VNONRELOC: {
|
|
discharge2anyreg(fs, e);
|
|
freeexp(fs, e);
|
|
e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.info, 0);
|
|
e->k = VRELOC;
|
|
break;
|
|
}
|
|
default: lua_assert(0); /* cannot happen */
|
|
}
|
|
/* interchange true and false lists */
|
|
{ int temp = e->f; e->f = e->t; e->t = temp; }
|
|
removevalues(fs, e->f); /* values are useless when negated */
|
|
removevalues(fs, e->t);
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether expression 'e' is a small literal string
|
|
*/
|
|
static int isKstr (FuncState *fs, expdesc *e) {
|
|
return (e->k == VK && !hasjumps(e) && e->u.info <= MAXARG_B &&
|
|
ttisshrstring(&fs->f->k[e->u.info]));
|
|
}
|
|
|
|
/*
|
|
** Check whether expression 'e' is a literal integer.
|
|
*/
|
|
int luaK_isKint (expdesc *e) {
|
|
return (e->k == VKINT && !hasjumps(e));
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether expression 'e' is a literal integer in
|
|
** proper range to fit in register C
|
|
*/
|
|
static int isCint (expdesc *e) {
|
|
return luaK_isKint(e) && (l_castS2U(e->u.ival) <= l_castS2U(MAXARG_C));
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether expression 'e' is a literal integer in
|
|
** proper range to fit in register sC
|
|
*/
|
|
static int isSCint (expdesc *e) {
|
|
return luaK_isKint(e) && fitsC(e->u.ival);
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether expression 'e' is a literal integer or float in
|
|
** proper range to fit in register sC
|
|
*/
|
|
static int isSCnumber (expdesc *e, lua_Integer *i) {
|
|
if (e->k == VKINT)
|
|
*i = e->u.ival;
|
|
else if (!(e->k == VKFLT && floatI(e->u.nval, i)))
|
|
return 0; /* not a number */
|
|
if (!hasjumps(e) && fitsC(*i)) {
|
|
*i += OFFSET_sC;
|
|
return 1;
|
|
}
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
** Create expression 't[k]'. 't' must have its final result already in a
|
|
** register or upvalue. Upvalues can only be indexed by literal strings.
|
|
** Keys can be literal strings in the constant table or arbitrary
|
|
** values in registers.
|
|
*/
|
|
void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
|
|
lua_assert(!hasjumps(t) && (vkisinreg(t->k) || t->k == VUPVAL));
|
|
if (t->k == VUPVAL && !isKstr(fs, k)) /* upvalue indexed by non string? */
|
|
luaK_exp2anyreg(fs, t); /* put it in a register */
|
|
t->u.ind.t = t->u.info; /* register or upvalue index */
|
|
if (t->k == VUPVAL) {
|
|
t->u.ind.idx = k->u.info; /* literal string */
|
|
t->k = VINDEXUP;
|
|
}
|
|
else if (isKstr(fs, k)) {
|
|
t->u.ind.idx = k->u.info; /* literal string */
|
|
t->k = VINDEXSTR;
|
|
}
|
|
else if (isCint(k)) {
|
|
t->u.ind.idx = cast_int(k->u.ival); /* integer constant in proper range */
|
|
t->k = VINDEXI;
|
|
}
|
|
else {
|
|
t->u.ind.idx = luaK_exp2anyreg(fs, k); /* register */
|
|
t->k = VINDEXED;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Return false if folding can raise an error.
|
|
** Bitwise operations need operands convertible to integers; division
|
|
** operations cannot have 0 as divisor.
|
|
*/
|
|
static int validop (int op, TValue *v1, TValue *v2) {
|
|
switch (op) {
|
|
case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR:
|
|
case LUA_OPSHL: case LUA_OPSHR: case LUA_OPBNOT: { /* conversion errors */
|
|
lua_Integer i;
|
|
return (tointegerns(v1, &i) && tointegerns(v2, &i));
|
|
}
|
|
case LUA_OPDIV: case LUA_OPIDIV: case LUA_OPMOD: /* division by 0 */
|
|
return (nvalue(v2) != 0);
|
|
default: return 1; /* everything else is valid */
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Try to "constant-fold" an operation; return 1 iff successful.
|
|
** (In this case, 'e1' has the final result.)
|
|
*/
|
|
static int constfolding (FuncState *fs, int op, expdesc *e1,
|
|
const expdesc *e2) {
|
|
TValue v1, v2, res;
|
|
if (!tonumeral(e1, &v1) || !tonumeral(e2, &v2) || !validop(op, &v1, &v2))
|
|
return 0; /* non-numeric operands or not safe to fold */
|
|
luaO_rawarith(fs->ls->L, op, &v1, &v2, &res); /* does operation */
|
|
if (ttisinteger(&res)) {
|
|
e1->k = VKINT;
|
|
e1->u.ival = ivalue(&res);
|
|
}
|
|
else { /* folds neither NaN nor 0.0 (to avoid problems with -0.0) */
|
|
lua_Number n = fltvalue(&res);
|
|
if (luai_numisnan(n) || n == 0)
|
|
return 0;
|
|
e1->k = VKFLT;
|
|
e1->u.nval = n;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit code for unary expressions that "produce values"
|
|
** (everything but 'not').
|
|
** Expression to produce final result will be encoded in 'e'.
|
|
*/
|
|
static void codeunexpval (FuncState *fs, OpCode op, expdesc *e, int line) {
|
|
int r = luaK_exp2anyreg(fs, e); /* opcodes operate only on registers */
|
|
freeexp(fs, e);
|
|
e->u.info = luaK_codeABC(fs, op, 0, r, 0); /* generate opcode */
|
|
e->k = VRELOC; /* all those operations are relocatable */
|
|
luaK_fixline(fs, line);
|
|
}
|
|
|
|
|
|
static void finishbinexpval (FuncState *fs, expdesc *e1, expdesc *e2,
|
|
int pc, int line) {
|
|
freeexps(fs, e1, e2);
|
|
e1->u.info = pc;
|
|
e1->k = VRELOC; /* all those operations are relocatable */
|
|
luaK_fixline(fs, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit code for binary expressions that "produce values"
|
|
** (everything but logical operators 'and'/'or' and comparison
|
|
** operators).
|
|
** Expression to produce final result will be encoded in 'e1'.
|
|
** Because 'luaK_exp2anyreg' can free registers, its calls must be
|
|
** in "stack order" (that is, first on 'e2', which may have more
|
|
** recent registers to be released).
|
|
*/
|
|
static void codebinexpval (FuncState *fs, OpCode op,
|
|
expdesc *e1, expdesc *e2, int line) {
|
|
int v2 = luaK_exp2anyreg(fs, e2); /* both operands are in registers */
|
|
int v1 = luaK_exp2anyreg(fs, e1);
|
|
int pc = luaK_codeABC(fs, op, 0, v1, v2); /* generate opcode */
|
|
finishbinexpval(fs, e1, e2, pc, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Code binary operators ('+', '-', ...) with immediate operands.
|
|
*/
|
|
static void codebini (FuncState *fs, OpCode op,
|
|
expdesc *e1, expdesc *e2, int k, int line) {
|
|
int v2 = cast_int(e2->u.ival); /* immediate operand */
|
|
int v1 = luaK_exp2anyreg(fs, e1);
|
|
int pc = codeABsC(fs, op, 0, v1, v2, k); /* generate opcode */
|
|
finishbinexpval(fs, e1, e2, pc, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Code arithmetic operators ('+', '-', ...). If second operand is a
|
|
** constant in the proper range, use variant opcodes with immediate
|
|
** operands.
|
|
*/
|
|
static void codearith (FuncState *fs, OpCode op,
|
|
expdesc *e1, expdesc *e2, int flip, int line) {
|
|
if (!isSCint(e2))
|
|
codebinexpval(fs, op, e1, e2, line); /* use standard operators */
|
|
else /* use immediate operators */
|
|
codebini(fs, cast(OpCode, op - OP_ADD + OP_ADDI), e1, e2, flip, line);
|
|
}
|
|
|
|
|
|
static void swapexps (expdesc *e1, expdesc *e2) {
|
|
expdesc temp = *e1; *e1 = *e2; *e2 = temp; /* swap 'e1' and 'e2' */
|
|
}
|
|
|
|
|
|
/*
|
|
** Code commutative operators ('+', '*'). If first operand is a
|
|
** constant, change order of operands to use immediate operator.
|
|
*/
|
|
static void codecommutative (FuncState *fs, OpCode op,
|
|
expdesc *e1, expdesc *e2, int line) {
|
|
int flip = 0;
|
|
if (isSCint(e1)) {
|
|
swapexps(e1, e2);
|
|
flip = 1;
|
|
}
|
|
codearith(fs, op, e1, e2, flip, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Code bitwise operations; they are all associative, so the function
|
|
** tries to put an integer constant as the 2nd operand (a K operand).
|
|
*/
|
|
static void codebitwise (FuncState *fs, BinOpr opr,
|
|
expdesc *e1, expdesc *e2, int line) {
|
|
int inv = 0;
|
|
int v1, v2, pc;
|
|
OpCode op;
|
|
if (e1->k == VKINT && luaK_exp2RK(fs, e1)) {
|
|
swapexps(e1, e2); /* 'e2' will be the constant operand */
|
|
inv = 1;
|
|
}
|
|
else if (!(e2->k == VKINT && luaK_exp2RK(fs, e2))) { /* no constants? */
|
|
op = cast(OpCode, opr - OPR_BAND + OP_BAND);
|
|
codebinexpval(fs, op, e1, e2, line); /* all-register opcodes */
|
|
return;
|
|
}
|
|
v1 = luaK_exp2anyreg(fs, e1);
|
|
v2 = e2->u.info; /* index in K array */
|
|
op = cast(OpCode, opr - OPR_BAND + OP_BANDK);
|
|
lua_assert(ttisinteger(&fs->f->k[v2]));
|
|
pc = luaK_codeABCk(fs, op, 0, v1, v2, inv);
|
|
finishbinexpval(fs, e1, e2, pc, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Code shift operators. If second operand is constant, use immediate
|
|
** operand (negating it if shift is in the other direction).
|
|
*/
|
|
static void codeshift (FuncState *fs, OpCode op,
|
|
expdesc *e1, expdesc *e2, int line) {
|
|
if (isSCint(e2)) {
|
|
int changedir = 0;
|
|
if (op == OP_SHL) {
|
|
changedir = 1;
|
|
e2->u.ival = -(e2->u.ival);
|
|
}
|
|
codebini(fs, OP_SHRI, e1, e2, changedir, line);
|
|
}
|
|
else
|
|
codebinexpval(fs, op, e1, e2, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit code for order comparisons.
|
|
** When the first operand A is an integral value in the proper range,
|
|
** change (A < B) to (B > A) and (A <= B) to (B >= A) so that
|
|
** it can use an immediate operand.
|
|
*/
|
|
static void codeorder (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
|
|
int r1, r2;
|
|
lua_Integer im;
|
|
if (isSCnumber(e2, &im)) {
|
|
/* use immediate operand */
|
|
r1 = luaK_exp2anyreg(fs, e1);
|
|
r2 = cast_int(im);
|
|
op = cast(OpCode, (op - OP_LT) + OP_LTI);
|
|
}
|
|
else if (isSCnumber(e1, &im)) {
|
|
/* transform (A < B) to (B > A) and (A <= B) to (B >= A) */
|
|
r1 = luaK_exp2anyreg(fs, e2);
|
|
r2 = cast_int(im);
|
|
op = (op == OP_LT) ? OP_GTI : OP_GEI;
|
|
}
|
|
else { /* regular case, compare two registers */
|
|
r1 = luaK_exp2anyreg(fs, e1);
|
|
r2 = luaK_exp2anyreg(fs, e2);
|
|
}
|
|
freeexps(fs, e1, e2);
|
|
e1->u.info = condjump(fs, op, r1, r2, 1);
|
|
e1->k = VJMP;
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit code for equality comparisons ('==', '~=').
|
|
** 'e1' was already put as RK by 'luaK_infix'.
|
|
*/
|
|
static void codeeq (FuncState *fs, BinOpr opr, expdesc *e1, expdesc *e2) {
|
|
int r1, r2;
|
|
lua_Integer im;
|
|
OpCode op;
|
|
if (e1->k != VNONRELOC) {
|
|
lua_assert(e1->k == VK || e1->k == VKINT || e1->k == VKFLT);
|
|
swapexps(e1, e2);
|
|
}
|
|
r1 = luaK_exp2anyreg(fs, e1); /* 1nd expression must be in register */
|
|
if (isSCnumber(e2, &im)) {
|
|
op = OP_EQI;
|
|
r2 = cast_int(im); /* immediate operand */
|
|
}
|
|
else if (luaK_exp2RK(fs, e2)) { /* 1st expression is constant? */
|
|
op = OP_EQK;
|
|
r2 = e2->u.info; /* constant index */
|
|
}
|
|
else {
|
|
op = OP_EQ; /* will compare two registers */
|
|
r2 = luaK_exp2anyreg(fs, e2);
|
|
}
|
|
freeexps(fs, e1, e2);
|
|
e1->u.info = condjump(fs, op, r1, r2, (opr == OPR_EQ));
|
|
e1->k = VJMP;
|
|
}
|
|
|
|
|
|
/*
|
|
** Apply prefix operation 'op' to expression 'e'.
|
|
*/
|
|
void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) {
|
|
static const expdesc ef = {VKINT, {0}, NO_JUMP, NO_JUMP};
|
|
switch (op) {
|
|
case OPR_MINUS: case OPR_BNOT: /* use 'ef' as fake 2nd operand */
|
|
if (constfolding(fs, op + LUA_OPUNM, e, &ef))
|
|
break;
|
|
/* FALLTHROUGH */
|
|
case OPR_LEN:
|
|
codeunexpval(fs, cast(OpCode, op + OP_UNM), e, line);
|
|
break;
|
|
case OPR_NOT: codenot(fs, e); break;
|
|
default: lua_assert(0);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Process 1st operand 'v' of binary operation 'op' before reading
|
|
** 2nd operand.
|
|
*/
|
|
void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
|
|
switch (op) {
|
|
case OPR_AND: {
|
|
luaK_goiftrue(fs, v); /* go ahead only if 'v' is true */
|
|
break;
|
|
}
|
|
case OPR_OR: {
|
|
luaK_goiffalse(fs, v); /* go ahead only if 'v' is false */
|
|
break;
|
|
}
|
|
case OPR_CONCAT: {
|
|
luaK_exp2nextreg(fs, v); /* operand must be on the stack */
|
|
break;
|
|
}
|
|
case OPR_ADD: case OPR_SUB:
|
|
case OPR_MUL: case OPR_DIV: case OPR_IDIV:
|
|
case OPR_MOD: case OPR_POW:
|
|
case OPR_BAND: case OPR_BOR: case OPR_BXOR:
|
|
case OPR_SHL: case OPR_SHR: {
|
|
if (!tonumeral(v, NULL))
|
|
luaK_exp2anyreg(fs, v);
|
|
/* else keep numeral, which may be folded with 2nd operand */
|
|
break;
|
|
}
|
|
case OPR_EQ: case OPR_NE: {
|
|
if (!tonumeral(v, NULL))
|
|
luaK_exp2RK(fs, v);
|
|
/* else keep numeral, which may be an immediate operand */
|
|
break;
|
|
}
|
|
case OPR_LT: case OPR_LE:
|
|
case OPR_GT: case OPR_GE: {
|
|
lua_Integer dummy;
|
|
if (!isSCnumber(v, &dummy))
|
|
luaK_exp2anyreg(fs, v);
|
|
/* else keep numeral, which may be an immediate operand */
|
|
break;
|
|
}
|
|
default: lua_assert(0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Create code for '(e1 .. e2)'.
|
|
** For '(e1 .. e2.1 .. e2.2)' (which is '(e1 .. (e2.1 .. e2.2))',
|
|
** because concatenation is right associative), merge both CONCATs.
|
|
*/
|
|
static void codeconcat (FuncState *fs, expdesc *e1, expdesc *e2, int line) {
|
|
Instruction *ie2 = previousinstruction(fs);
|
|
if (GET_OPCODE(*ie2) == OP_CONCAT) { /* is 'e2' a concatenation? */
|
|
int n = GETARG_B(*ie2); /* # of elements concatenated in 'e2' */
|
|
lua_assert(e1->u.info + 1 == GETARG_A(*ie2));
|
|
freeexp(fs, e2);
|
|
SETARG_A(*ie2, e1->u.info); /* correct first element ('e1') */
|
|
SETARG_B(*ie2, n + 1); /* will concatenate one more element */
|
|
}
|
|
else { /* 'e2' is not a concatenation */
|
|
luaK_codeABC(fs, OP_CONCAT, e1->u.info, 2, 0); /* new concat opcode */
|
|
freeexp(fs, e2);
|
|
luaK_fixline(fs, line);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Finalize code for binary operation, after reading 2nd operand.
|
|
*/
|
|
void luaK_posfix (FuncState *fs, BinOpr opr,
|
|
expdesc *e1, expdesc *e2, int line) {
|
|
switch (opr) {
|
|
case OPR_AND: {
|
|
lua_assert(e1->t == NO_JUMP); /* list closed by 'luK_infix' */
|
|
luaK_dischargevars(fs, e2);
|
|
luaK_concat(fs, &e2->f, e1->f);
|
|
*e1 = *e2;
|
|
break;
|
|
}
|
|
case OPR_OR: {
|
|
lua_assert(e1->f == NO_JUMP); /* list closed by 'luK_infix' */
|
|
luaK_dischargevars(fs, e2);
|
|
luaK_concat(fs, &e2->t, e1->t);
|
|
*e1 = *e2;
|
|
break;
|
|
}
|
|
case OPR_CONCAT: { /* e1 .. e2 */
|
|
luaK_exp2nextreg(fs, e2);
|
|
codeconcat(fs, e1, e2, line);
|
|
break;
|
|
}
|
|
case OPR_ADD: case OPR_MUL: {
|
|
if (!constfolding(fs, opr + LUA_OPADD, e1, e2))
|
|
codecommutative(fs, cast(OpCode, opr + OP_ADD), e1, e2, line);
|
|
break;
|
|
}
|
|
case OPR_SUB: case OPR_DIV:
|
|
case OPR_IDIV: case OPR_MOD: case OPR_POW: {
|
|
if (!constfolding(fs, opr + LUA_OPADD, e1, e2))
|
|
codearith(fs, cast(OpCode, opr + OP_ADD), e1, e2, 0, line);
|
|
break;
|
|
}
|
|
case OPR_BAND: case OPR_BOR: case OPR_BXOR: {
|
|
if (!constfolding(fs, opr + LUA_OPADD, e1, e2))
|
|
codebitwise(fs, opr, e1, e2, line);
|
|
break;
|
|
}
|
|
case OPR_SHL: {
|
|
if (!constfolding(fs, LUA_OPSHL, e1, e2)) {
|
|
if (isSCint(e1)) {
|
|
swapexps(e1, e2);
|
|
codebini(fs, OP_SHLI, e1, e2, 1, line);
|
|
}
|
|
else
|
|
codeshift(fs, OP_SHL, e1, e2, line);
|
|
}
|
|
break;
|
|
}
|
|
case OPR_SHR: {
|
|
if (!constfolding(fs, LUA_OPSHR, e1, e2))
|
|
codeshift(fs, OP_SHR, e1, e2, line);
|
|
break;
|
|
}
|
|
case OPR_EQ: case OPR_NE: {
|
|
codeeq(fs, opr, e1, e2);
|
|
break;
|
|
}
|
|
case OPR_LT: case OPR_LE: {
|
|
OpCode op = cast(OpCode, (opr - OPR_EQ) + OP_EQ);
|
|
codeorder(fs, op, e1, e2);
|
|
break;
|
|
}
|
|
case OPR_GT: case OPR_GE: {
|
|
/* '(a > b)' <=> '(b < a)'; '(a >= b)' <=> '(b <= a)' */
|
|
OpCode op = cast(OpCode, (opr - OPR_NE) + OP_EQ);
|
|
swapexps(e1, e2);
|
|
codeorder(fs, op, e1, e2);
|
|
break;
|
|
}
|
|
default: lua_assert(0);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Change line information associated with current position, by removing
|
|
** previous info and adding it again with new line.
|
|
*/
|
|
void luaK_fixline (FuncState *fs, int line) {
|
|
removelastlineinfo(fs);
|
|
savelineinfo(fs, fs->f, line);
|
|
}
|
|
|
|
|
|
/*
|
|
** Emit a SETLIST instruction.
|
|
** 'base' is register that keeps table;
|
|
** 'nelems' is #table plus those to be stored now;
|
|
** 'tostore' is number of values (in registers 'base + 1',...) to add to
|
|
** table (or LUA_MULTRET to add up to stack top).
|
|
*/
|
|
void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
|
|
int c = (nelems - 1)/LFIELDS_PER_FLUSH + 1;
|
|
int b = (tostore == LUA_MULTRET) ? 0 : tostore;
|
|
lua_assert(tostore != 0 && tostore <= LFIELDS_PER_FLUSH);
|
|
if (c <= MAXARG_C)
|
|
luaK_codeABC(fs, OP_SETLIST, base, b, c);
|
|
else if (c <= MAXARG_Ax) {
|
|
luaK_codeABC(fs, OP_SETLIST, base, b, 0);
|
|
codeextraarg(fs, c);
|
|
}
|
|
else
|
|
luaX_syntaxerror(fs->ls, "constructor too long");
|
|
fs->freereg = base + 1; /* free registers with list values */
|
|
}
|
|
|
|
|
|
/*
|
|
** return the final target of a jump (skipping jumps to jumps)
|
|
*/
|
|
static int finaltarget (Instruction *code, int i) {
|
|
int count;
|
|
for (count = 0; count < 100; count++) { /* avoid infinite loops */
|
|
Instruction pc = code[i];
|
|
if (GET_OPCODE(pc) != OP_JMP)
|
|
break;
|
|
else
|
|
i += GETARG_sJ(pc) + 1;
|
|
}
|
|
return i;
|
|
}
|
|
|
|
|
|
/*
|
|
** Do a final pass over the code of a function, doing small peephole
|
|
** optimizations and adjustments.
|
|
*/
|
|
void luaK_finish (FuncState *fs) {
|
|
int i;
|
|
Proto *p = fs->f;
|
|
for (i = 0; i < fs->pc; i++) {
|
|
Instruction *pc = &p->code[i];
|
|
lua_assert(i == 0 || isOT(*(pc - 1)) == isIT(*pc));
|
|
switch (GET_OPCODE(*pc)) {
|
|
case OP_RETURN0: case OP_RETURN1: {
|
|
if (p->sizep == 0 && !p->is_vararg)
|
|
break; /* no extra work */
|
|
/* else use OP_RETURN to do the extra work */
|
|
SET_OPCODE(*pc, OP_RETURN);
|
|
} /* FALLTHROUGH */
|
|
case OP_RETURN: case OP_TAILCALL: {
|
|
if (p->sizep > 0 || p->is_vararg) {
|
|
SETARG_C(*pc, p->is_vararg ? p->numparams + 1 : 0);
|
|
SETARG_k(*pc, 1); /* signal that there is extra work */
|
|
}
|
|
break;
|
|
}
|
|
case OP_JMP: {
|
|
int target = finaltarget(p->code, i);
|
|
fixjump(fs, i, target);
|
|
break;
|
|
}
|
|
default: break;
|
|
}
|
|
}
|
|
}
|