jumps are relative to next instruction

lopcodes.h

@@ -1,5 +1,5 @@
 /*
-** $Id: lopcodes.h,v 1.5 1997/09/24 19:43:11 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.6 1997/10/01 20:05:34 roberto Exp roberto $
 ** Opcodes for Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -18,60 +18,60 @@
 typedef enum {
 /* name          parm    before          after           side effect
 -----------------------------------------------------------------------------*/
-ENDCODE,
+ENDCODE,/*	-	-		-  */
 
-PUSHNIL,/*		-		nil  */
+PUSHNIL,/*	-	-		nil  */
 PUSHNILS,/*	b	-		nil_1...nil_b  */
 
-PUSH0,/*		-		0.0  */
-PUSH1,/*		-		1.0  */
-PUSH2,/*		-		2.0  */
+PUSH0,/*	-	-		0.0  */
+PUSH1,/*	-	-		1.0  */
+PUSH2,/*	-	-		2.0  */
 PUSHBYTE,/*	b	-		(float)b  */
 PUSHWORD,/*	w	-		(float)w  */
 
-PUSHCONSTANT0,/*	-		CNST[0] */
-PUSHCONSTANT1,/*	-		CNST[1] */
-PUSHCONSTANT2,/*	-		CNST[2] */
-PUSHCONSTANT3,/*	-		CNST[3] */
-PUSHCONSTANT4,/*	-		CNST[4] */
-PUSHCONSTANT5,/*	-		CNST[5] */
-PUSHCONSTANT6,/*	-		CNST[6] */
-PUSHCONSTANT7,/*	-		CNST[7] */
-PUSHCONSTANT8,/*	-		CNST[8] */
-PUSHCONSTANT9,/*	-		CNST[9] */
+PUSHCONSTANT0,/*-	-		CNST[0] */
+PUSHCONSTANT1,/*-	-		CNST[1] */
+PUSHCONSTANT2,/*-	-		CNST[2] */
+PUSHCONSTANT3,/*-	-		CNST[3] */
+PUSHCONSTANT4,/*-	-		CNST[4] */
+PUSHCONSTANT5,/*-	-		CNST[5] */
+PUSHCONSTANT6,/*-	-		CNST[6] */
+PUSHCONSTANT7,/*-	-		CNST[7] */
+PUSHCONSTANT8,/*-	-		CNST[8] */
+PUSHCONSTANT9,/*-	-		CNST[9] */
 PUSHCONSTANTB,/*b	-		CNST[b] */
 PUSHCONSTANT,/* w	-		CNST[w] */
 
-PUSHUPVALUE0,
-PUSHUPVALUE1,
+PUSHUPVALUE0,/*	-	-		Closure[0] */
+PUSHUPVALUE1,/*	-	-		Closure[1] */
 PUSHUPVALUE,/*	b	-		Closure[b] */
 
-PUSHLOCAL0,/*		-		LOC[0]  */
-PUSHLOCAL1,/*		-		LOC[1]  */
-PUSHLOCAL2,/*		-		LOC[2]  */
-PUSHLOCAL3,/*		-		LOC[3]  */
-PUSHLOCAL4,/*		-		LOC[4]  */
-PUSHLOCAL5,/*		-		LOC[5]  */
-PUSHLOCAL6,/*		-		LOC[6]  */
-PUSHLOCAL7,/*		-		LOC[7]  */
-PUSHLOCAL8,/*		-		LOC[8]  */
-PUSHLOCAL9,/*		-		LOC[9]  */
+PUSHLOCAL0,/*	-	-		LOC[0]  */
+PUSHLOCAL1,/*	-	-		LOC[1]  */
+PUSHLOCAL2,/*	-	-		LOC[2]  */
+PUSHLOCAL3,/*	-	-		LOC[3]  */
+PUSHLOCAL4,/*	-	-		LOC[4]  */
+PUSHLOCAL5,/*	-	-		LOC[5]  */
+PUSHLOCAL6,/*	-	-		LOC[6]  */
+PUSHLOCAL7,/*	-	-		LOC[7]  */
+PUSHLOCAL8,/*	-	-		LOC[8]  */
+PUSHLOCAL9,/*	-	-		LOC[9]  */
 PUSHLOCAL,/*	b	-		LOC[b]  */
 
-GETGLOBAL0,/*		-		VAR[CNST[0]]  */
-GETGLOBAL1,/*		-		VAR[CNST[1]]  */
-GETGLOBAL2,/*		-		VAR[CNST[2]]  */
-GETGLOBAL3,/*		-		VAR[CNST[3]]  */
-GETGLOBAL4,/*		-		VAR[CNST[4]]  */
-GETGLOBAL5,/*		-		VAR[CNST[5]]  */
-GETGLOBAL6,/*		-		VAR[CNST[6]]  */
-GETGLOBAL7,/*		-		VAR[CNST[7]]  */
-GETGLOBAL8,/*		-		VAR[CNST[8]]  */
-GETGLOBAL9,/*		-		VAR[CNST[9]]  */
+GETGLOBAL0,/*	-	-		VAR[CNST[0]]  */
+GETGLOBAL1,/*	-	-		VAR[CNST[1]]  */
+GETGLOBAL2,/*	-	-		VAR[CNST[2]]  */
+GETGLOBAL3,/*	-	-		VAR[CNST[3]]  */
+GETGLOBAL4,/*	-	-		VAR[CNST[4]]  */
+GETGLOBAL5,/*	-	-		VAR[CNST[5]]  */
+GETGLOBAL6,/*	-	-		VAR[CNST[6]]  */
+GETGLOBAL7,/*	-	-		VAR[CNST[7]]  */
+GETGLOBAL8,/*	-	-		VAR[CNST[8]]  */
+GETGLOBAL9,/*	-	-		VAR[CNST[9]]  */
 GETGLOBALB,/*	b 	-		VAR[CNST[b]]  */
 GETGLOBAL,/*	w	-		VAR[CNST[w]]  */
 
-GETTABLE,/*		i t		t[i]  */
+GETTABLE,/*	-	i t		t[i]  */
 
 PUSHSELFB,/*	b	t		t t[CNST[b]]  */
 PUSHSELF,/*	w	t		t t[CNST[w]]  */
@@ -79,44 +79,43 @@ PUSHSELF,/*	w	t		t t[CNST[w]]  */
 CREATEARRAYB,/*	b	-		newarray(size = b)  */
 CREATEARRAY,/*	w	-		newarray(size = w)  */
 
-SETLOCAL0,/*		x		-		LOC[0]=x  */
-SETLOCAL1,/*		x		-		LOC[1]=x  */
-SETLOCAL2,/*		x		-		LOC[2]=x  */
-SETLOCAL3,/*		x		-		LOC[3]=x  */
-SETLOCAL4,/*		x		-		LOC[4]=x  */
-SETLOCAL5,/*		x		-		LOC[5]=x  */
-SETLOCAL6,/*		x		-		LOC[6]=x  */
-SETLOCAL7,/*		x		-		LOC[7]=x  */
-SETLOCAL8,/*		x		-		LOC[8]=x  */
-SETLOCAL9,/*		x		-		LOC[9]=x  */
+SETLOCAL0,/*	-	x		-		LOC[0]=x  */
+SETLOCAL1,/*	-	x		-		LOC[1]=x  */
+SETLOCAL2,/*	-	x		-		LOC[2]=x  */
+SETLOCAL3,/*	-	x		-		LOC[3]=x  */
+SETLOCAL4,/*	-	x		-		LOC[4]=x  */
+SETLOCAL5,/*	-	x		-		LOC[5]=x  */
+SETLOCAL6,/*	-	x		-		LOC[6]=x  */
+SETLOCAL7,/*	-	x		-		LOC[7]=x  */
+SETLOCAL8,/*	-	x		-		LOC[8]=x  */
+SETLOCAL9,/*	-	x		-		LOC[9]=x  */
 SETLOCAL,/*	b	x		-		LOC[b]=x  */
 
 SETGLOBALB,/*	b	x		-		VAR[CNST[b]]=x  */
 SETGLOBAL,/*	w	x		-		VAR[CNST[w]]=x  */
 
-SETTABLE0,/*		v i t		-		t[i]=v  */
+SETTABLE0,/*	-	v i t		-		t[i]=v  */
 SETTABLE,/*	b	v a_b...a_1 i t	a_b...a_1 i t	t[i]=v  */
 
 SETLIST0,/*	b	v_b...v_1 t	-		t[i]=v_i  */
 SETLIST,/*	b c	v_b...v_1 t	-		t[i+c*FPF]=v_i  */
 SETMAP,/*	b	v_b k_b ...v_1 k_1 t	t	t[k_i]=v_i  */
 
-EQOP,/*			y x		(x==y)? 1 : nil  */
-NEQOP,/*		y x		(x~=y)? 1 : nil  */
-LTOP,/*			y x		(x<y)? 1 : nil  */
-LEOP,/*			y x		(x<y)? 1 : nil  */
-GTOP,/*			y x		(x>y)? 1 : nil  */
-GEOP,/*			y x		(x>=y)? 1 : nil  */
-ADDOP,/*		y x		x+y  */
-SUBOP,/*		y x		x-y  */
-MULTOP,/*		y x		x*y  */
-DIVOP,/*		y x		x/y  */
-POWOP,/*		y x		x^y  */
-CONCOP,/*		y x		x..y  */
-MINUSOP,/*		x		-x  */
-NOTOP,/*		x		(x==nil)? 1 : nil  */
-
-/* NOTICE: all jumps are relative to the position following the opcode */
+EQOP,/*		-	y x		(x==y)? 1 : nil  */
+NEQOP,/*	-	y x		(x~=y)? 1 : nil  */
+LTOP,/*		-	y x		(x<y)? 1 : nil  */
+LEOP,/*		-	y x		(x<y)? 1 : nil  */
+GTOP,/*		-	y x		(x>y)? 1 : nil  */
+GEOP,/*		-	y x		(x>=y)? 1 : nil  */
+ADDOP,/*	-	y x		x+y  */
+SUBOP,/*	-	y x		x-y  */
+MULTOP,/*	-	y x		x*y  */
+DIVOP,/*	-	y x		x/y  */
+POWOP,/*	-	y x		x^y  */
+CONCOP,/*	-	y x		x..y  */
+MINUSOP,/*	-	x		-x  */
+NOTOP,/*	-	x		(x==nil)? 1 : nil  */
+
 ONTJMP,/*	b	x		(x!=nil)? x : -	(x!=nil)? PC+=b  */
 ONFJMP,/*	b	x		(x==nil)? x : -	(x==nil)? PC+=b  */
 JMPB,/*		b	-		-		PC+=b  */
@@ -134,8 +133,8 @@ CLOSURE,/*	w	v_1...v_n	c(CNST[w]) */
 CALLFUNC,/*	b c	v_b...v_1 f	r_c...r_1	f(v1,...,v_b)  */
 RETCODE,/*	b	-		-  */
 SETLINE,/*	w	-		-		LINE=w  */
-POP1,/*			-		-		TOP-=1  */
-POP2,/*			-		-		TOP-=2  */
+POP1,/*		-	-		-		TOP-=1  */
+POP2,/*		-	-		-		TOP-=2  */
 POPS,/*		b	-		-		TOP-=b  */
 ARGS,/*		b	-		-		TOP=BASE+b  */
 VARARGS/*	b	v_x...v_1	{v_1...v_x;n=x}	TOP=BASE+b+1  */

lua.stx

@@ -1,6 +1,6 @@
 %{
 /*
-** $Id: lua.stx,v 1.6 1997/09/26 15:02:26 roberto Exp roberto $
+** $Id: lua.stx,v 1.7 1997/10/01 20:05:34 roberto Exp roberto $
 ** Syntax analizer and code generator
 ** See Copyright Notice in lua.h
 */
@@ -135,31 +135,6 @@ static void code_word (int n)
 }
 
 
-static int fix_opcode (int pc, OpCode op, int n)
-{
-  if (n <= 255) {
-    currState->f->code[pc] = op;
-    currState->f->code[pc+1] = n;
-    return 0;
-  }
-  else {
-    check_pc(1);  /* open space */
-    movecode_up(pc+1, pc, currState->pc-pc);
-    currState->pc++;
-    currState->f->code[pc] = op+1;  /* opcode must be word variant */
-    code_word_at(pc+1, n);
-    return 1;
-  }
-}
-
-static int fix_jump (int pc, OpCode op, int n)
-{
-  n -= pc+1;  /* jump is relative to position following jump opcode */
-  if (n > 255) n++;  /* jump must be 1 bigger */
-  return fix_opcode(pc, op, n);
-}
-
-
 static void deltastack (int delta)
 {
   currState->stacksize += delta;
@@ -501,6 +476,39 @@ static int lua_codestore (int i, int left)
 }
 
 
+static int fix_opcode (int pc, OpCode op, int n)
+{
+  if (n <= 255) {
+    currState->f->code[pc] = op;
+    currState->f->code[pc+1] = n;
+    return 0;
+  }
+  else {
+    check_pc(1);  /* open space */
+    movecode_up(pc+1, pc, currState->pc-pc);
+    currState->pc++;
+    currState->f->code[pc] = op+1;  /* opcode must be word variant */
+    code_word_at(pc+1, n);
+    return 1;
+  }
+}
+
+
+static int fix_jump (int pc, OpCode op, int n)
+{
+  /* jump is relative to position following jump instruction */
+  return fix_opcode(pc, op, n-(pc+JMPSIZE));
+}
+
+
+static void fix_upjmp (OpCode op, int pos)
+{
+  int delta = currState->pc+JMPSIZE - pos;  /* jump is relative */
+  if (delta > 255) delta++;
+  code_opborw(op, delta, 0);
+}
+
+
 static void codeIf (int thenAdd, int elseAdd)
 {
   int elseinit = elseAdd+JMPSIZE;
@@ -516,7 +524,7 @@ static void codeIf (int thenAdd, int elseAdd)
 
 static void code_shortcircuit (OpCode op, int pos)
 {
-  int dist = currState->pc - (pos+1);
+  int dist = currState->pc - (pos+JMPSIZE);
   if (dist > 255)
     luaY_error("and/or expression too long");
   currState->f->code[pos] = op;
@@ -578,7 +586,6 @@ static void init_func (void)
 }
 
 
-
 static TProtoFunc *close_func (void)
 {
   TProtoFunc *f = currState->f;
@@ -681,12 +688,13 @@ stat   : IF cond THEN block SaveWord elsepart END
                 &currState->f->code[$2], expsize);
 	 movecode_down($2, $3, currState->pc-$2);
 	 newpos += fix_jump($2, JMPB, currState->pc-expsize);
-	 code_opborw(IFTUPJMPB, currState->pc+1 - newpos, 0);
+	 fix_upjmp(IFTUPJMPB, newpos);
        }}
 
        | REPEAT GetPC block UNTIL expr1
        {
-         code_opborw(IFFUPJMPB, currState->pc+1 - $2, -1);
+	 fix_upjmp(IFFUPJMPB, $2);
+	 deltastack(-1);  /* pops condition */
        }
 
        | varlist1 '=' exprlist1

lvm.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 1.6 1997/09/26 15:02:26 roberto Exp roberto $
+** $Id: lvm.c,v 1.7 1997/10/01 20:05:34 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -570,51 +570,51 @@ StkId luaV_execute (Closure *cl, StkId base)
         break;
 
       case ONTJMP:
-        if (ttype(luaD_stack.top-1) != LUA_T_NIL) pc += *pc;
-        else { pc++; luaD_stack.top--; }
+        aux = *pc++;
+        if (ttype(luaD_stack.top-1) != LUA_T_NIL) pc += aux;
+        else luaD_stack.top--;
         break;
 
       case ONFJMP:
-        if (ttype(luaD_stack.top-1) == LUA_T_NIL) pc += *pc;
-        else { pc++; luaD_stack.top--; }
-        break;
-
-      case JMPB:
-        pc += *pc;
+        aux = *pc++;
+        if (ttype(luaD_stack.top-1) == LUA_T_NIL) pc += aux;
+        else luaD_stack.top--;
         break;
 
       case JMP:
-        pc += get_word(pc);
-        break;
+        aux = next_word(pc); goto jmp;
 
-      case IFFJMPB:
-        if (ttype(--luaD_stack.top) == LUA_T_NIL) pc += *pc;
-        else pc++;
+      case JMPB:
+        aux = *pc++;
+      jmp:
+        pc += aux;
         break;
 
       case IFFJMP:
-        if (ttype(--luaD_stack.top) == LUA_T_NIL) pc += get_word(pc);
-        else skip_word(pc);
-        break;
+        aux = next_word(pc); goto iffjmp;
 
-      case IFTUPJMPB:
-        if (ttype(--luaD_stack.top) != LUA_T_NIL) pc -= *pc;
-        else pc++;
+      case IFFJMPB:
+        aux = *pc++;
+      iffjmp:
+        if (ttype(--luaD_stack.top) == LUA_T_NIL) pc += aux;
         break;
 
       case IFTUPJMP:
-        if (ttype(--luaD_stack.top) != LUA_T_NIL) pc -= get_word(pc);
-        else skip_word(pc);
-        break;
+        aux = next_word(pc); goto iftupjmp;
 
-      case IFFUPJMPB:
-        if (ttype(--luaD_stack.top) == LUA_T_NIL) pc -= *pc;
-        else pc++;
+      case IFTUPJMPB:
+        aux = *pc++;
+      iftupjmp:
+        if (ttype(--luaD_stack.top) != LUA_T_NIL) pc -= aux;
         break;
 
       case IFFUPJMP:
-        if (ttype(--luaD_stack.top) == LUA_T_NIL) pc -= get_word(pc);
-        else skip_word(pc);
+        aux = next_word(pc); goto iffupjmp;
+
+      case IFFUPJMPB:
+        aux = *pc++;
+      iffupjmp:
+        if (ttype(--luaD_stack.top) == LUA_T_NIL) pc -= aux;
         break;
 
       case CLOSURE: