more optimizations

lcode.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.c,v 1.20 2000/04/05 17:51:58 roberto Exp roberto $
+** $Id: lcode.c,v 1.21 2000/04/06 17:36:52 roberto Exp roberto $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -88,9 +88,11 @@ static void luaK_minus (FuncState *fs) {
 
 static void luaK_gettable (FuncState *fs) {
   /* PUSHSTRING u; GETTABLE -> GETDOTTED u   (t.x) */
+  /* GETLOCAL u; GETTABLE  -> GETINDEXED u   (t[i]) */
   Instruction previous = prepare(fs, CREATE_0(OP_GETTABLE), -1);
   switch(GET_OPCODE(previous)) {
     case OP_PUSHSTRING: SET_OPCODE(previous, OP_GETDOTTED); break;
+    case OP_GETLOCAL: SET_OPCODE(previous, OP_GETINDEXED); break;
     default: return;
   }
   setprevious(fs, previous);
@@ -123,22 +125,32 @@ static void luaK_sub (FuncState *fs) {
 
 
 static void luaK_conc (FuncState *fs) {
-  /* CONC u; CONC 2 -> CONC u+1   (a..b..c) */
-  Instruction previous = prepare(fs, CREATE_U(OP_CONC, 2), -1);
+  /* CONCAT u; CONCAT 2 -> CONCAT u+1   (a..b..c) */
+  Instruction previous = prepare(fs, CREATE_U(OP_CONCAT, 2), -1);
   switch(GET_OPCODE(previous)) {
-    case OP_CONC: SETARG_U(previous, GETARG_U(previous)+1); break;
+    case OP_CONCAT: SETARG_U(previous, GETARG_U(previous)+1); break;
     default: return;
   }
   setprevious(fs, previous);
 }
 
 
+static void luaK_getlocal (FuncState *fs, int l) {
+  /* SETLOCAL l 1; GETLOCAL l -> SETLOCAL l 0 */
+  Instruction previous = prepare(fs, CREATE_U(OP_GETLOCAL, l), 1);
+  if (previous == CREATE_AB(OP_SETLOCAL, l, 1)) {
+    SETARG_B(previous, 0);
+    setprevious(fs, previous);
+  }
+}
+
+
 static void luaK_setlocal (FuncState *fs, int l) {
-  /* PUSHLOCAL l; ADDI k, SETLOCAL l -> INCLOCAL k, l   ((local)a=a+k) */
+  /* GETLOCAL l; ADDI k, SETLOCAL l -> INCLOCAL k, l   ((local)a=a+k) */
   Instruction *code = fs->f->code;
   int pc = fs->pc;
   if (pc-1 > fs->lasttarget &&  /* no jumps in-between instructions? */
-      code[pc-2] == CREATE_U(OP_PUSHLOCAL, l) &&
+      code[pc-2] == CREATE_U(OP_GETLOCAL, l) &&
       GET_OPCODE(code[pc-1]) == OP_ADDI &&
       abs(GETARG_S(code[pc-1])) <= MAXARG_sA) {
     int inc = GETARG_S(code[pc-1]);
@@ -147,7 +159,7 @@ static void luaK_setlocal (FuncState *fs, int l) {
     luaK_deltastack(fs, -1);
   }
   else
-    luaK_U(fs, OP_SETLOCAL, l, -1);
+    luaK_AB(fs, OP_SETLOCAL, l, 1, -1);
 }
 
 
@@ -162,8 +174,8 @@ static void luaK_eq (FuncState *fs) {
 
 
 static void luaK_neq (FuncState *fs) {
-  /* PUSHNIL 1; JMPNEQ -> JMPT   (a~=nil) */
-  Instruction previous = prepare(fs, CREATE_S(OP_JMPNEQ, NO_JUMP), -2);
+  /* PUSHNIL 1; JMPNE -> JMPT   (a~=nil) */
+  Instruction previous = prepare(fs, CREATE_S(OP_JMPNE, NO_JUMP), -2);
   if (previous == CREATE_U(OP_PUSHNIL, 1)) {
     setprevious(fs, CREATE_S(OP_JMPT, NO_JUMP));
   }
@@ -201,6 +213,17 @@ static void luaK_pushnil (FuncState *fs, int n) {
 }
 
 
+static void luaK_pop (FuncState *fs, int n) {
+  Instruction previous = prepare(fs, CREATE_U(OP_POP, n), -n);
+  switch(GET_OPCODE(previous)) {
+    case OP_SETTABLE: SETARG_B(previous, GETARG_B(previous)+n); break;
+    case OP_SETLOCAL: SETARG_B(previous, GETARG_B(previous)+n); break;
+    default: return;
+  }
+  setprevious(fs, previous);
+}
+
+
 static void luaK_fixjump (FuncState *fs, int pc, int dest) {
   Instruction *jmp = &fs->f->code[pc];
   if (dest == NO_JUMP)
@@ -280,7 +303,7 @@ void luaK_number (FuncState *fs, Number f) {
 
 void luaK_adjuststack (FuncState *fs, int n) {
   if (n > 0)
-    luaK_U(fs, OP_POP, n, -n);
+    luaK_pop(fs, n);
   else if (n < 0)
     luaK_pushnil(fs, -n);
 }
@@ -311,7 +334,7 @@ static void assertglobal (FuncState *fs, int index) {
 static int discharge (FuncState *fs, expdesc *var) {
   switch (var->k) {
     case VLOCAL:
-      luaK_U(fs, OP_PUSHLOCAL, var->u.index, 1);
+      luaK_getlocal(fs, var->u.index);
       break;
     case VGLOBAL:
       luaK_U(fs, OP_GETGLOBAL, var->u.index, 1);
@@ -347,8 +370,8 @@ void luaK_storevar (LexState *ls, const expdesc *var) {
       luaK_U(fs, OP_SETGLOBAL, var->u.index, -1);
       assertglobal(fs, var->u.index);  /* make sure that there is a global */
       break;
-    case VINDEXED:
-      luaK_0(fs, OP_SETTABLEPOP, -3);
+    case VINDEXED:  /* table is at top-3; pop 3 elements after operation */
+      luaK_AB(fs, OP_SETTABLE, 3, 3, -3);
       break;
     default:
       LUA_INTERNALERROR(ls->L, "invalid var kind to store");
@@ -358,8 +381,8 @@ void luaK_storevar (LexState *ls, const expdesc *var) {
 
 static OpCode invertjump (OpCode op) {
   switch (op) {
-    case OP_JMPNEQ: return OP_JMPEQ;
-    case OP_JMPEQ: return OP_JMPNEQ;
+    case OP_JMPNE: return OP_JMPEQ;
+    case OP_JMPEQ: return OP_JMPNE;
     case OP_JMPLT: return OP_JMPGE;
     case OP_JMPLE: return OP_JMPGT;
     case OP_JMPGT: return OP_JMPLE;
@@ -566,7 +589,7 @@ void luaK_posfix (LexState *ls, int op, expdesc *v1, expdesc *v2) {
       case '*': luaK_0(fs, OP_MULT, -1); break;
       case '/': luaK_0(fs, OP_DIV, -1); break;
       case '^': luaK_0(fs, OP_POW, -1); break;
-      case TK_CONC: luaK_conc(fs); break;
+      case TK_CONCAT: luaK_conc(fs); break;
       case TK_EQ: luaK_eq(fs); break;
       case TK_NE: luaK_neq(fs); break;
       case '>': luaK_S(fs, OP_JMPGT, NO_JUMP, -2); break;

lparser.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.c,v 1.76 2000/04/05 17:51:58 roberto Exp roberto $
+** $Id: lparser.c,v 1.77 2000/04/06 17:36:52 roberto Exp roberto $
 ** LL(1) Parser and code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -751,7 +751,7 @@ static int get_priority (int op, int *rp) {
 
     case  '+': case  '-': *rp = 5; return 5;
 
-    case  TK_CONC: *rp = 3; return 4;  /* right associative (?) */
+    case  TK_CONCAT: *rp = 3; return 4;  /* right associative (?) */
 
     case TK_EQ: case  TK_NE: case  '>': case  '<': case  TK_LE: case  TK_GE:
       *rp = 2; return 2;
@@ -832,13 +832,11 @@ static int assignment (LexState *ls, expdesc *v, int nvars) {
     nexps = explist1(ls);
     adjust_mult_assign(ls, nvars, nexps);
   }
-  if (v->k != VINDEXED || left+(nvars-1) == 0) {
-    /* global/local var or indexed var without values in between */
+  if (v->k != VINDEXED)
     luaK_storevar(ls, v);
-  }
-  else {  /* indexed var with values in between*/
-    luaK_U(ls->fs, OP_SETTABLE, left+(nvars-1), -1);
-    left += 2;  /* table&index are not popped, because they aren't on top */
+  else {  /* there may be garbage between table-index and value */
+    luaK_AB(ls->fs, OP_SETTABLE, left+nvars+2, 1, -1);
+    left += 2;
   }
   return left;
 }

lvm.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 1.98 2000/03/29 20:19:20 roberto Exp roberto $
+** $Id: lvm.c,v 1.99 2000/04/04 20:48:44 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -231,6 +231,13 @@ static void call_arith (lua_State *L, StkId top, IMS event) {
 }
 
 
+static void addK (lua_State *L, StkId top, int k) {
+  ttype(top) = TAG_NUMBER;
+  nvalue(top) = (Number)k;
+  call_arith(L, top+1, IM_ADD);
+}
+
+
 static int luaV_strcomp (const TString *ls, const TString *rs) {
   const char *l = ls->str;
   long ll = ls->u.s.len;
@@ -403,7 +410,7 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         *top++ = cl->consts[GETARG_U(i)];
         break;
 
-      case OP_PUSHLOCAL:
+      case OP_GETLOCAL:
         *top++ = *(base+GETARG_U(i));
         break;
 
@@ -424,6 +431,12 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         top--;
         break;
 
+      case OP_GETINDEXED:
+        *top++ = *(base+GETARG_U(i));
+        luaV_gettable(L, top);
+        top--;
+        break;
+
       case OP_PUSHSELF: {
         TObject receiver;
         receiver = *(top-1);
@@ -443,7 +456,8 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         break;
 
       case OP_SETLOCAL:
-        *(base+GETARG_U(i)) = *(--top);
+        *(base+GETARG_A(i)) = *(top-1);
+        top -= GETARG_B(i);
         break;
 
       case OP_SETGLOBAL:
@@ -451,14 +465,9 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         top--;
         break;
 
-      case OP_SETTABLEPOP:
-        luaV_settable(L, top-3, top);
-        top -= 3;  /* pop table, index, and value */
-        break;
-
       case OP_SETTABLE:
-        luaV_settable(L, top-3-GETARG_U(i), top);
-        top--;  /* pop value */
+        luaV_settable(L, top-GETARG_A(i), top);
+        top -= GETARG_B(i);  /* pop values */
         break;
 
       case OP_SETLIST: {
@@ -496,9 +505,7 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         int n = GETARG_sA(i);
         if (tonumber(var)) {
           *top = *var;  /* PUSHLOCAL */
-          ttype(top+1) = TAG_NUMBER;
-          nvalue(top+1) = (Number)n;  /* PUSHINT */
-          call_arith(L, top+2, IM_ADD);
+          addK(L, top+1, n);
           *var = *top;  /* SETLOCAL */
         }
         else
@@ -507,11 +514,8 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
       }
 
       case OP_ADDI:
-        if (tonumber(top-1)) {
-          ttype(top) = TAG_NUMBER;
-          nvalue(top) = (Number)GETARG_S(i);
-          call_arith(L, top+1, IM_ADD);
-        }
+        if (tonumber(top-1))
+          addK(L, top, GETARG_S(i));
         else
           nvalue(top-1) += (Number)GETARG_S(i);
         break;
@@ -545,7 +549,7 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         top--;
         break;
 
-      case OP_CONC: {
+      case OP_CONCAT: {
         int n = GETARG_U(i);
         strconc(L, n, top);
         top -= n-1;
@@ -569,7 +573,7 @@ StkId luaV_execute (lua_State *L, const Closure *cl, register StkId base) {
         nvalue(top-1) = 1;
         break;
 
-      case OP_JMPNEQ:
+      case OP_JMPNE:
         top -= 2;
         if (!luaO_equalObj(top, top+1)) pc += GETARG_S(i);
         break;