commit d388c165ef79cb9c668e28fa92242ffbc0430e54
parent ab07005568a399f2e97996677472d9e6e69c9f4f
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 18 Dec 2017 15:53:23 -0200
new opcodes 'FORLOOP1'/'FORPREP1' for "basic for" (integer variable
with increment of 1)
Diffstat:
4 files changed, 73 insertions(+), 18 deletions(-)
diff --git a/lopcodes.c b/lopcodes.c
@@ -1,5 +1,5 @@
/*
-** $Id: lopcodes.c,v 1.72 2017/12/04 17:41:30 roberto Exp roberto $
+** $Id: lopcodes.c,v 1.73 2017/12/13 18:32:09 roberto Exp roberto $
** Opcodes for Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -82,6 +82,8 @@ LUAI_DDEF const char *const luaP_opnames[NUM_OPCODES+1] = {
"RETURN",
"RETURN0",
"RETURN1",
+ "FORLOOP1",
+ "FORPREP1",
"FORLOOP",
"FORPREP",
"TFORCALL",
@@ -160,6 +162,8 @@ LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES] = {
,opmode(0, 0, iABC) /* OP_RETURN */
,opmode(0, 0, iABC) /* OP_RETURN0 */
,opmode(0, 0, iABC) /* OP_RETURN1 */
+ ,opmode(0, 1, iABx) /* OP_FORLOOP1 */
+ ,opmode(0, 1, iABx) /* OP_FORPREP1 */
,opmode(0, 1, iABx) /* OP_FORLOOP */
,opmode(0, 1, iABx) /* OP_FORPREP */
,opmode(0, 0, iABC) /* OP_TFORCALL */
diff --git a/lopcodes.h b/lopcodes.h
@@ -1,5 +1,5 @@
/*
-** $Id: lopcodes.h,v 1.178 2017/12/15 18:35:22 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.179 2017/12/15 18:53:48 roberto Exp roberto $
** Opcodes for Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -267,6 +267,10 @@ OP_RETURN,/* A B return R(A), ... ,R(A+B-2) (see note) */
OP_RETURN0,/* return */
OP_RETURN1,/* A return R(A) */
+OP_FORLOOP1,/* A Bx R(A)++;
+ if R(A) <= R(A+1) then { pc-=Bx; R(A+3)=R(A) } */
+OP_FORPREP1,/* A Bx R(A)--; pc+=Bx */
+
OP_FORLOOP,/* A Bx R(A)+=R(A+2);
if R(A) <?= R(A+1) then { pc-=Bx; R(A+3)=R(A) } */
OP_FORPREP,/* A Bx R(A)-=R(A+2); pc+=Bx */
diff --git a/lparser.c b/lparser.c
@@ -1,5 +1,5 @@
/*
-** $Id: lparser.c,v 2.172 2017/12/15 13:07:10 roberto Exp roberto $
+** $Id: lparser.c,v 2.173 2017/12/18 12:33:54 roberto Exp roberto $
** Lua Parser
** See Copyright Notice in lua.h
*/
@@ -1313,11 +1313,20 @@ static void repeatstat (LexState *ls, int line) {
}
-static void exp1 (LexState *ls) {
+/*
+** Read an expression and generate code to put its results in next
+** stack slot. Return true if expression is a constant integer and,
+** if 'i' is not-zero, its value is equal to 'i'.
+**
+*/
+static int exp1 (LexState *ls, int i) {
expdesc e;
+ int res;
expr(ls, &e);
+ res = luaK_isKint(&e) && (i == 0 || i == e.u.ival);
luaK_exp2nextreg(ls->fs, &e);
lua_assert(e.k == VNONRELOC);
+ return res;
}
@@ -1337,29 +1346,37 @@ static void fixforjump (FuncState *fs, int pc, int dest, int back) {
}
-static void forbody (LexState *ls, int base, int line, int nvars, int isnum) {
+/*
+** Generate code for a 'for' loop. 'kind' can be zero (a common for
+** loop), one (a basic for loop, with integer values and increment of
+** 1), or two (a generic for loop).
+*/
+static void forbody (LexState *ls, int base, int line, int nvars, int kind) {
/* forbody -> DO block */
BlockCnt bl;
FuncState *fs = ls->fs;
int prep, endfor;
adjustlocalvars(ls, 3); /* control variables */
checknext(ls, TK_DO);
- prep = isnum ? luaK_codeABx(fs, OP_FORPREP, base, 0) : luaK_jump(fs);
+ prep = (kind == 0) ? luaK_codeABx(fs, OP_FORPREP, base, 0)
+ : (kind == 1) ? luaK_codeABx(fs, OP_FORPREP1, base, 0)
+ : luaK_jump(fs);
enterblock(fs, &bl, 0); /* scope for declared variables */
adjustlocalvars(ls, nvars);
luaK_reserveregs(fs, nvars);
block(ls);
leaveblock(fs); /* end of scope for declared variables */
- if (isnum) { /* numeric for? */
- fixforjump(fs, prep, luaK_getlabel(fs), 0);
- endfor = luaK_codeABx(fs, OP_FORLOOP, base, 0);
- }
- else { /* generic for */
+ if (kind == 2) { /* generic for? */
luaK_patchtohere(fs, prep);
luaK_codeABC(fs, OP_TFORCALL, base, 0, nvars);
luaK_fixline(fs, line);
endfor = luaK_codeABx(fs, OP_TFORLOOP, base + 2, 0);
}
+ else {
+ fixforjump(fs, prep, luaK_getlabel(fs), 0);
+ endfor = (kind == 0) ? luaK_codeABx(fs, OP_FORLOOP, base, 0)
+ : luaK_codeABx(fs, OP_FORLOOP1, base, 0);
+ }
fixforjump(fs, endfor, prep + 1, 1);
luaK_fixline(fs, line);
}
@@ -1369,21 +1386,25 @@ static void fornum (LexState *ls, TString *varname, int line) {
/* fornum -> NAME = exp,exp[,exp] forbody */
FuncState *fs = ls->fs;
int base = fs->freereg;
+ int basicfor = 1; /* true if it is a "basic" 'for' (integer + 1) */
new_localvarliteral(ls, "(for index)");
new_localvarliteral(ls, "(for limit)");
new_localvarliteral(ls, "(for step)");
new_localvar(ls, varname);
checknext(ls, '=');
- exp1(ls); /* initial value */
+ if (!exp1(ls, 0)) /* initial value not an integer? */
+ basicfor = 0; /* not a basic 'for' */
checknext(ls, ',');
- exp1(ls); /* limit */
- if (testnext(ls, ','))
- exp1(ls); /* optional step */
+ exp1(ls, 0); /* limit */
+ if (testnext(ls, ',')) {
+ if (!exp1(ls, 1)) /* optional step not 1? */
+ basicfor = 0; /* not a basic 'for' */
+ }
else { /* default step = 1 */
luaK_int(fs, fs->freereg, 1);
luaK_reserveregs(fs, 1);
}
- forbody(ls, base, line, 1, 1);
+ forbody(ls, base, line, 1, basicfor);
}
@@ -1408,7 +1429,7 @@ static void forlist (LexState *ls, TString *indexname) {
line = ls->linenumber;
adjust_assign(ls, 3, explist(ls, &e), &e);
luaK_checkstack(fs, 3); /* extra space to call generator */
- forbody(ls, base, line, nvars - 3, 0);
+ forbody(ls, base, line, nvars - 3, 2);
}
diff --git a/lvm.c b/lvm.c
@@ -1,5 +1,5 @@
/*
-** $Id: lvm.c,v 2.324 2017/12/04 17:41:30 roberto Exp roberto $
+** $Id: lvm.c,v 2.326 2017/12/18 17:49:31 roberto Exp $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -1564,6 +1564,32 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
}
return;
}
+ vmcase(OP_FORLOOP1) {
+ lua_Integer idx = intop(+, ivalue(vra), 1); /* increment index */
+ lua_Integer limit = ivalue(s2v(ra + 1));
+ if (idx <= limit) {
+ pc -= GETARG_Bx(i); /* jump back */
+ chgivalue(vra, idx); /* update internal index... */
+ setivalue(s2v(ra + 3), idx); /* ...and external index */
+ }
+ updatetrap(ci);
+ vmbreak;
+ }
+ vmcase(OP_FORPREP1) {
+ TValue *init = vra;
+ TValue *plimit = s2v(ra + 1);
+ lua_Integer ilimit, initv;
+ int stopnow;
+ if (!forlimit(plimit, &ilimit, 1, &stopnow)) {
+ savepc(L); /* for the error message */
+ luaG_runerror(L, "'for' limit must be a number");
+ }
+ initv = (stopnow ? 0 : ivalue(init));
+ setivalue(plimit, ilimit);
+ setivalue(init, intop(-, initv, 1));
+ pc += GETARG_Bx(i);
+ vmbreak;
+ }
vmcase(OP_FORLOOP) {
if (ttisinteger(vra)) { /* integer loop? */
lua_Integer step = ivalue(s2v(ra + 2));
