commit 18cd7adac6e5745cad93fecacbe6a2ed16dd3e18
parent 41223a01eccafa03990ca6d89124b0955001a9ce
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Fri, 24 Oct 1997 16:40:08 -0200
optimization to handle <a.x> (new opcode).
Diffstat:
| M | lopcodes.h | | | 13 | ++++++++++++- |
| M | lua.stx | | | 68 | +++++++++++++++++++++++++++++++++++++++++++++++--------------------- |
| M | lvm.c | | | 16 | +++++++++++++++- |
3 files changed, 74 insertions(+), 23 deletions(-)
diff --git a/lopcodes.h b/lopcodes.h
@@ -1,5 +1,5 @@
/*
-** $Id: lopcodes.h,v 1.10 1997/10/16 21:14:47 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.11 1997/10/24 17:17:24 roberto Exp roberto $
** Opcodes for Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -67,6 +67,17 @@ GETGLOBALW,/* w - VAR[CNST[w]] */
GETTABLE,/* - i t t[i] */
+GETDOTTED,/* b t t[CONST[b]] */
+GETDOTTED0,/* - t t[CONST[0]] */
+GETDOTTED1,/* - t t[CONST[1]] */
+GETDOTTED2,/* - t t[CONST[2]] */
+GETDOTTED3,/* - t t[CONST[3]] */
+GETDOTTED4,/* - t t[CONST[4]] */
+GETDOTTED5,/* - t t[CONST[5]] */
+GETDOTTED6,/* - t t[CONST[6]] */
+GETDOTTED7,/* - t t[CONST[7]] */
+GETDOTTEDW,/* w t t[CONST[w]] */
+
PUSHSELF,/* b t t t[CNST[b]] */
PUSHSELFW,/* w t t t[CNST[w]] */
diff --git a/lua.stx b/lua.stx
@@ -1,6 +1,6 @@
%{
/*
-** $Id: lua.stx,v 1.12 1997/10/18 16:46:39 roberto Exp roberto $
+** $Id: lua.stx,v 1.13 1997/10/24 17:17:24 roberto Exp roberto $
** Syntax analizer and code generator
** See Copyright Notice in lua.h
*/
@@ -31,6 +31,8 @@ int luaY_parse (void);
/* maximum number of local variables */
#define MAXLOCALS 32
+#define MINGLOBAL (MAXLOCALS+1)
+
/* maximum number of variables in a multiple assignment */
#define MAXVAR 32
@@ -41,13 +43,21 @@ int luaY_parse (void);
#define MAXUPVALUES 16
/*
-** Variable descriptor: if n>0, represents global variable indexed
-** by (n-1); if n<0, represents local variable index (-n)-1;
-** if n==0, represents an indexed variable (table and index on top of stack)
+** Variable descriptor:
+** if 0<n<MINGLOBAL, represents local variable indexed by (n-1);
+** if MINGLOBAL<=n, represents global variable at position (n-MINGLOBAL);
+** if n<0, indexed variable with index (-n)-1 (table on top of stack);
+** if n==0, an indexed variable (table and index on top of stack)
** Must be long to store negative Word values.
*/
typedef long vardesc;
+#define isglobal(v) (MINGLOBAL<=(v))
+#define globalindex(v) ((v)-MINGLOBAL)
+#define islocal(v) (0<(v) && (v)<MINGLOBAL)
+#define localindex(v) ((v)-1)
+#define isdot(v) (v<0)
+#define dotindex(v) ((-(v))-1)
/* state needed to generate code for a given function */
typedef struct State {
@@ -313,11 +323,25 @@ static void add_localvar (TaggedString *name)
currState->nlocalvar++;
}
+
+/*
+** dotted variables <a.x> must be stored like regular indexed vars <a["x"]>
+*/
+static vardesc var2store (vardesc var)
+{
+ if (isdot(var)) {
+ code_constant(dotindex(var));
+ var = 0;
+ }
+ return var;
+}
+
+
static void add_varbuffer (vardesc var, int n)
{
if (n >= MAXVAR)
luaY_error("variable buffer overflow");
- currState->varbuffer[n] = var;
+ currState->varbuffer[n] = var2store(var);
}
@@ -338,9 +362,9 @@ static vardesc singlevar (TaggedString *n, State *st)
for (l=1; l<=(st-mainState); l++)
if (aux_localname(n, st-l) >= 0)
luaY_syntaxerror("cannot access a variable in outer scope", n->str);
- return string_constant(n, st)+1; /* positive value */
+ return string_constant(n, st)+MINGLOBAL; /* global value */
}
- else return -(i+1); /* negative value */
+ else return i+1; /* local value */
}
@@ -353,7 +377,7 @@ static int indexupvalue (TaggedString *n)
return i;
}
/* new one */
- if (++currState->nupvalues > MAXUPVALUES)
+ if (++(currState->nupvalues) > MAXUPVALUES)
luaY_error("too many upvalues in a single function");
currState->upvalues[i] = v; /* i = currState->nupvalues - 1 */
return i;
@@ -435,25 +459,27 @@ static void code_args (int nparams, int dots)
}
-static void lua_pushvar (vardesc number)
+static void lua_pushvar (vardesc var)
{
- if (number > 0) /* global var */
- code_oparg(GETGLOBAL, 8, number-1, 1);
- else if (number < 0) /* local var */
- code_oparg(PUSHLOCAL, 8, (-number)-1, 1);
+ if (isglobal(var))
+ code_oparg(GETGLOBAL, 8, globalindex(var), 1);
+ else if (islocal(var))
+ code_oparg(PUSHLOCAL, 8, localindex(var), 1);
+ else if (isdot(var))
+ code_oparg(GETDOTTED, 8, dotindex(var), 0);
else
code_pop(GETTABLE);
}
-static void storevar (vardesc number)
+static void storevar (vardesc var)
{
- if (number == 0) /* indexed var */
+ if (var == 0) /* indexed var */
code_opcode(SETTABLE0, -3);
- else if (number > 0) /* global var */
- code_oparg(SETGLOBAL, 8, number-1, -1);
- else /* number < 0 - local var */
- code_oparg(SETLOCAL, 8, (-number)-1, -1);
+ else if (isglobal(var))
+ code_oparg(SETGLOBAL, 8, globalindex(var), -1);
+ else /* local var */
+ code_oparg(SETLOCAL, 8, localindex(var), -1);
}
@@ -698,7 +724,7 @@ block : {$<vInt>$ = currState->nlocalvar;} chunk
}
;
-funcname : var { init_func(); $$ = $1; }
+funcname : var { $$ = var2store($1); init_func(); }
| varexp ':' NAME
{
code_string($3);
@@ -872,7 +898,7 @@ varlist1 : var { $$ = 1; add_varbuffer($1, 0); }
var : NAME { $$ = singlevar($1, currState); }
| varexp '[' expr1 ']' { $$ = 0; } /* indexed variable */
- | varexp '.' NAME { code_string($3); $$ = 0; }/* ind. var. */
+ | varexp '.' NAME { $$ = (-string_constant($3, currState))-1; }
;
varexp : var { lua_pushvar($1); }
diff --git a/lvm.c b/lvm.c
@@ -1,5 +1,5 @@
/*
-** $Id: lvm.c,v 1.10 1997/10/16 10:59:34 roberto Exp roberto $
+** $Id: lvm.c,v 1.11 1997/10/24 17:17:24 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -335,6 +335,20 @@ StkId luaV_execute (Closure *cl, StkId base)
luaV_gettable();
break;
+ case GETDOTTEDW:
+ aux = next_word(pc); goto getdotted;
+
+ case GETDOTTED:
+ aux = *pc++; goto getdotted;
+
+ case GETDOTTED0: case GETDOTTED1: case GETDOTTED2: case GETDOTTED3:
+ case GETDOTTED4: case GETDOTTED5: case GETDOTTED6: case GETDOTTED7:
+ aux -= GETDOTTED0;
+ getdotted:
+ *luaD_stack.top++ = consts[aux];
+ luaV_gettable();
+ break;
+
case PUSHSELFW:
aux = next_word(pc); goto pushself;
