From 28d47a0aaa646f8762085cc7fcf8953b62df0927 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Wed, 1 Oct 1997 17:05:34 -0300 Subject: [PATCH] all jumps have byte variants; WHILE optimization --- lopcodes.h | 9 ++-- lua.stx | 133 +++++++++++++++++++++++++++++++++++------------------ lvm.c | 66 +++++++++++++------------- 3 files changed, 129 insertions(+), 79 deletions(-) diff --git a/lopcodes.h b/lopcodes.h index e1b95122..f6bf4818 100644 --- 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 index 2f650f4e..8fd89517 100644 --- 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; if->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 NUMBER %token NAME STRING -%type PrepJump, PrepJumpPop, PrepJumpSC +%type SaveWord, cond, GetPC, SaveWordPop, SaveWordPush %type exprlist, exprlist1 /* if > 0, points to function return counter (which has list length); if <= 0, -list lenght */ %type 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 {$$=currState->pc;} expr1 DO PrepJumpPop block END - { - code_opborw(UPJMPB, currState->pc+1 - ($2), 0); - fix_jump($5, IFFJMP, currState->pc - ($5+1)); - } + | WHILE GetPC cond DO block END + {{ + int expsize = $3-$2; + int newpos = $2+JMPSIZE; + check_pc(expsize); + memcpy(&currState->f->code[currState->pc], + &currState->f->code[$2], expsize); + movecode_down($2, $3, currState->pc-$2); + newpos += fix_jump($2, JMPB, currState->pc-expsize); + code_opborw(IFTUPJMPB, currState->pc+1 - newpos, 0); + }} - | REPEAT {$$=currState->pc;} block UNTIL expr1 + | REPEAT GetPC block UNTIL expr1 { - code_opborw(IFFUPJMPB, currState->pc+1 - ($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); - } - ; - -PrepJumpSC : /* empty */ - { $$ = currState->pc; code_opcode(0, -1); code_byte(0); } +GetPC : /* empty */ { $$ = currState->pc; } ; -PrepJumpPop : PrepJump { $$ = $1; deltastack(-1); /* pop condition */ } +SaveWord : GetPC { $$ = $1; code_word(0); /* open space */ } + ; + +SaveWordPop : SaveWord { $$ = $1; deltastack(-1); /* pop condition */ } + ; + +SaveWordPush : SaveWord { $$ = $1; deltastack(1); /* push a value */ } + ; + +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); $$ = 0; } ; -table : - { $$ = currState->pc+1; code_opw(CREATEARRAY, 0, 1); } - '{' fieldlist '}' - { code_word_at($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 index 6051067e..5f9db8f9 100644 --- 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; - break; - - case UPJMP: - pc -= get_word(pc); + case IFFJMPB: + if (ttype(--luaD_stack.top) == LUA_T_NIL) pc += *pc; + else pc++; break; case IFFJMP: - 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 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: