commit 28d47a0aaa646f8762085cc7fcf8953b62df0927
parent eb617df2d87f8476e722ade7319998d7912a6edf
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Wed, 1 Oct 1997 17:05:13 -0300
all jumps have byte variants; WHILE optimization
Diffstat:
| M | lopcodes.h | | | 9 | ++++++--- |
| M | lua.stx | | | 129 | +++++++++++++++++++++++++++++++++++++++++++++++++++++-------------------------- |
| M | lvm.c | | | 64 | +++++++++++++++++++++++++++++++++------------------------------- |
3 files changed, 126 insertions(+), 76 deletions(-)
diff --git a/lopcodes.h b/lopcodes.h
@@ -1,5 +1,5 @@
/*
-** $Id: lopcodes.h,v 1.4 1997/09/22 20:53:20 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.5 1997/09/24 19:43:11 roberto Exp roberto $
** Opcodes for Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -76,6 +76,7 @@ GETTABLE,/* i t t[i] */
PUSHSELFB,/* b t t t[CNST[b]] */
PUSHSELF,/* w t t t[CNST[w]] */
+CREATEARRAYB,/* b - newarray(size = b) */
CREATEARRAY,/* w - newarray(size = w) */
SETLOCAL0,/* x - LOC[0]=x */
@@ -118,10 +119,12 @@ NOTOP,/* x (x==nil)? 1 : nil */
/* NOTICE: all jumps are relative to the position following the opcode */
ONTJMP,/* b x (x!=nil)? x : - (x!=nil)? PC+=b */
ONFJMP,/* b x (x==nil)? x : - (x==nil)? PC+=b */
+JMPB,/* b - - PC+=b */
JMP,/* w - - PC+=w */
-UPJMPB,/* b - - PC-=b */
-UPJMP,/* w - - PC-=w */
+IFFJMPB,/* b x - (x==nil)? PC+=b */
IFFJMP,/* w x - (x==nil)? PC+=w */
+IFTUPJMPB,/* b x - (x!=nil)? PC-=b */
+IFTUPJMP,/* w x - (x!=nil)? PC-=w */
IFFUPJMPB,/* b x - (x==nil)? PC-=b */
IFFUPJMP,/* w x - (x==nil)? PC-=w */
diff --git a/lua.stx b/lua.stx
@@ -1,6 +1,6 @@
%{
/*
-** $Id: lua.stx,v 1.5 1997/09/24 19:43:11 roberto Exp roberto $
+** $Id: lua.stx,v 1.6 1997/09/26 15:02:26 roberto Exp roberto $
** Syntax analizer and code generator
** See Copyright Notice in lua.h
*/
@@ -28,6 +28,9 @@ int luaY_parse (void);
#define free luaM_free
+/* size of a "normal" jump instruction: OpCode + 1 byte */
+#define JMPSIZE 2
+
/* maximum number of local variables */
#define MAXLOCALS 32
@@ -85,11 +88,32 @@ void luaY_error (char *s)
}
-static void code_byte (Byte c)
+static void check_pc (int n)
{
- if (currState->pc >= currState->maxcode)
+ if (currState->pc+n > currState->maxcode)
currState->maxcode = luaM_growvector(&currState->f->code,
currState->maxcode, Byte, codeEM, MAX_INT);
+}
+
+
+static void movecode_up (int d, int s, int n)
+{
+ while (n--)
+ currState->f->code[d+n] = currState->f->code[s+n];
+}
+
+
+static void movecode_down (int d, int s, int n)
+{
+ int i;
+ for (i=0; i<n; i++)
+ currState->f->code[d+i] = currState->f->code[s+i];
+}
+
+
+static void code_byte (Byte c)
+{
+ check_pc(1);
currState->f->code[currState->pc++] = c;
}
@@ -103,19 +127,36 @@ static void code_word_at (int pc, int n)
}
-static void fix_jump (int pc, OpCode op, int n)
+static void code_word (int n)
{
- currState->f->code[pc] = op;
- code_word_at(pc+1, n);
+ check_pc(2);
+ currState->pc += 2;
+ code_word_at(currState->pc-2, n);
}
-static void code_word (int n)
+static int fix_opcode (int pc, OpCode op, int n)
{
- if (n > MAX_WORD)
- luaY_error("construction too big; unable to compile");
- code_byte(n&0xFF);
- code_byte(n>>8);
+ 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);
}
@@ -462,14 +503,14 @@ static int lua_codestore (int i, int left)
static void codeIf (int thenAdd, int elseAdd)
{
- int elseinit = elseAdd+sizeof(Word)+1;
+ int elseinit = elseAdd+JMPSIZE;
if (currState->pc == elseinit) { /* no else part */
- currState->pc -= sizeof(Word)+1;
+ currState->pc -= JMPSIZE;
elseinit = currState->pc;
}
else
- fix_jump(elseAdd, JMP, currState->pc-(elseAdd+1));
- fix_jump(thenAdd, IFFJMP, elseinit-(thenAdd+1));
+ elseinit += fix_jump(elseAdd, JMPB, currState->pc);
+ fix_jump(thenAdd, IFFJMPB, elseinit);
}
@@ -593,7 +634,7 @@ TProtoFunc *luaY_parser (ZIO *z, char *chunkname)
%token <vReal> NUMBER
%token <pTStr> NAME STRING
-%type <vInt> PrepJump, PrepJumpPop, PrepJumpSC
+%type <vInt> SaveWord, cond, GetPC, SaveWordPop, SaveWordPush
%type <vLong> exprlist, exprlist1 /* if > 0, points to function return
counter (which has list length); if <= 0, -list lenght */
%type <vLong> functioncall, expr /* if != 0, points to function return
@@ -628,18 +669,24 @@ statlist : /* empty */
sc : /* empty */ | ';' ;
-stat : IF expr1 THEN PrepJumpPop block PrepJump elsepart END
- { codeIf($4, $6); }
+stat : IF cond THEN block SaveWord elsepart END
+ { codeIf($2, $5); }
- | WHILE {$<vInt>$=currState->pc;} expr1 DO PrepJumpPop block END
- {
- code_opborw(UPJMPB, currState->pc+1 - ($<vInt>2), 0);
- fix_jump($5, IFFJMP, currState->pc - ($5+1));
- }
+ | WHILE GetPC cond DO block END
+ {{
+ int expsize = $3-$2;
+ int newpos = $2+JMPSIZE;
+ check_pc(expsize);
+ memcpy(&currState->f->code[currState->pc],
+ &currState->f->code[$2], expsize);
+ movecode_down($2, $3, currState->pc-$2);
+ newpos += fix_jump($2, JMPB, currState->pc-expsize);
+ code_opborw(IFTUPJMPB, currState->pc+1 - newpos, 0);
+ }}
- | REPEAT {$<vInt>$=currState->pc;} block UNTIL expr1
+ | REPEAT GetPC block UNTIL expr1
{
- code_opborw(IFFUPJMPB, currState->pc+1 - ($<vInt>2), -1);
+ code_opborw(IFFUPJMPB, currState->pc+1 - $2, -1);
}
| varlist1 '=' exprlist1
@@ -687,8 +734,8 @@ body : '(' parlist ')' chunk END { $$ = close_func(); }
elsepart : /* empty */
| ELSE block
- | ELSEIF expr1 THEN PrepJumpPop block PrepJump elsepart
- { codeIf($4, $6); }
+ | ELSEIF cond THEN block SaveWord elsepart
+ { codeIf($2, $5); }
;
ret : /* empty */
@@ -699,19 +746,19 @@ ret : /* empty */
}
;
-PrepJump : /* empty */
- {
- $$ = currState->pc;
- code_byte(0); /* open space */
- code_word(0);
- }
+GetPC : /* empty */ { $$ = currState->pc; }
+ ;
+
+SaveWord : GetPC { $$ = $1; code_word(0); /* open space */ }
;
-PrepJumpSC : /* empty */
- { $$ = currState->pc; code_opcode(0, -1); code_byte(0); }
+SaveWordPop : SaveWord { $$ = $1; deltastack(-1); /* pop condition */ }
+ ;
+
+SaveWordPush : SaveWord { $$ = $1; deltastack(1); /* push a value */ }
;
-PrepJumpPop : PrepJump { $$ = $1; deltastack(-1); /* pop condition */ }
+cond : expr1 SaveWordPop { $$ = $2; }
;
expr1 : expr { adjust_functioncall($1, 1); }
@@ -739,14 +786,11 @@ expr : '(' expr ')' { $$ = $2; }
| NIL {code_opcode(PUSHNIL, 1); $$ = 0; }
| functioncall { $$ = $1; }
| FUNCTION { init_func(); } body { func_onstack($3); $$ = 0; }
- | expr1 AND PrepJumpSC expr1 { code_shortcircuit(ONFJMP, $3); $$ = 0; }
- | expr1 OR PrepJumpSC expr1 { code_shortcircuit(ONTJMP, $3); $$ = 0; }
+ | expr1 AND SaveWordPop expr1 { code_shortcircuit(ONFJMP, $3); $$ = 0; }
+ | expr1 OR SaveWordPop expr1 { code_shortcircuit(ONTJMP, $3); $$ = 0; }
;
-table :
- { $<vInt>$ = currState->pc+1; code_opw(CREATEARRAY, 0, 1); }
- '{' fieldlist '}'
- { code_word_at($<vInt>1, $3); }
+table : '{' SaveWordPush fieldlist '}' { fix_opcode($2, CREATEARRAYB, $3); }
;
functioncall : funcvalue funcParams
@@ -892,3 +936,4 @@ decinit : /* empty */ { $$ = 0; }
;
%%
+
diff --git a/lvm.c b/lvm.c
@@ -1,5 +1,5 @@
/*
-** $Id: lvm.c,v 1.5 1997/09/24 19:43:11 roberto Exp roberto $
+** $Id: lvm.c,v 1.6 1997/09/26 15:02:26 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -452,8 +452,13 @@ StkId luaV_execute (Closure *cl, StkId base)
break;
case CREATEARRAY:
+ aux = next_word(pc); goto createarray;
+
+ case CREATEARRAYB:
+ aux = *pc++;
+ createarray:
luaC_checkGC();
- avalue(luaD_stack.top) = luaH_new(next_word(pc));
+ avalue(luaD_stack.top) = luaH_new(aux);
ttype(luaD_stack.top) = LUA_T_ARRAY;
luaD_stack.top++;
break;
@@ -565,54 +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--;
- }
+ if (ttype(luaD_stack.top-1) != LUA_T_NIL) pc += *pc;
+ else { pc++; luaD_stack.top--; }
break;
case ONFJMP:
- if (ttype(luaD_stack.top-1) == LUA_T_NIL)
- pc += *pc;
- else {
- pc++;
- luaD_stack.top--;
- }
+ if (ttype(luaD_stack.top-1) == LUA_T_NIL) pc += *pc;
+ else { pc++; luaD_stack.top--; }
+ break;
+
+ case JMPB:
+ pc += *pc;
break;
case JMP:
pc += get_word(pc);
break;
- case UPJMPB:
- pc -= *pc;
+ case IFFJMPB:
+ if (ttype(--luaD_stack.top) == LUA_T_NIL) pc += *pc;
+ else pc++;
break;
- case UPJMP:
- pc -= get_word(pc);
+ case IFFJMP:
+ if (ttype(--luaD_stack.top) == LUA_T_NIL) pc += get_word(pc);
+ else skip_word(pc);
break;
- case IFFJMP:
- if (ttype(--luaD_stack.top) == LUA_T_NIL)
- pc += get_word(pc);
- else
- skip_word(pc);
+ case IFTUPJMPB:
+ if (ttype(--luaD_stack.top) != LUA_T_NIL) pc -= *pc;
+ else pc++;
+ break;
+
+ case IFTUPJMP:
+ if (ttype(--luaD_stack.top) != LUA_T_NIL) pc -= get_word(pc);
+ else skip_word(pc);
break;
case IFFUPJMPB:
- if (ttype(--luaD_stack.top) == LUA_T_NIL)
- pc -= *pc;
- else
- pc++;
+ if (ttype(--luaD_stack.top) == LUA_T_NIL) pc -= *pc;
+ else pc++;
break;
case IFFUPJMP:
- if (ttype(--luaD_stack.top) == LUA_T_NIL)
- pc -= get_word(pc);
- else
- skip_word(pc);
+ if (ttype(--luaD_stack.top) == LUA_T_NIL) pc -= get_word(pc);
+ else skip_word(pc);
break;
case CLOSURE:
