New instruction format for SETLIST/NEWTABLE

New instruction format 'ivABC' (a variant of iABC where parameter vC has
10 bits) allows constructors of up to 1024 elements to be coded without
EXTRAARG.

lcode.c

@@ -390,32 +390,40 @@ int luaK_code (FuncState *fs, Instruction i) {
 ** Format and emit an 'iABC' instruction. (Assertions check consistency
 ** of parameters versus opcode.)
 */
-int luaK_codeABCk (FuncState *fs, OpCode o, int a, int b, int c, int k) {
+int luaK_codeABCk (FuncState *fs, OpCode o, int A, int B, int C, int k) {
   lua_assert(getOpMode(o) == iABC);
-  lua_assert(a <= MAXARG_A && b <= MAXARG_B &&
-             c <= MAXARG_C && (k & ~1) == 0);
-  return luaK_code(fs, CREATE_ABCk(o, a, b, c, k));
+  lua_assert(A <= MAXARG_A && B <= MAXARG_B &&
+             C <= MAXARG_C && (k & ~1) == 0);
+  return luaK_code(fs, CREATE_ABCk(o, A, B, C, k));
+}
+
+
+int luaK_codevABCk (FuncState *fs, OpCode o, int A, int B, int C, int k) {
+  lua_assert(getOpMode(o) == ivABC);
+  lua_assert(A <= MAXARG_A && B <= MAXARG_vB &&
+             C <= MAXARG_vC && (k & ~1) == 0);
+  return luaK_code(fs, CREATE_vABCk(o, A, B, C, k));
 }
 
 
 /*
 ** Format and emit an 'iABx' instruction.
 */
-int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
+int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned int Bc) {
   lua_assert(getOpMode(o) == iABx);
-  lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx);
-  return luaK_code(fs, CREATE_ABx(o, a, bc));
+  lua_assert(A <= MAXARG_A && Bc <= MAXARG_Bx);
+  return luaK_code(fs, CREATE_ABx(o, A, Bc));
 }
 
 
 /*
 ** Format and emit an 'iAsBx' instruction.
 */
-static int codeAsBx (FuncState *fs, OpCode o, int a, int bc) {
-  unsigned int b = bc + OFFSET_sBx;
+static int codeAsBx (FuncState *fs, OpCode o, int A, int Bc) {
+  unsigned int b = cast_uint(Bc) + OFFSET_sBx;
   lua_assert(getOpMode(o) == iAsBx);
-  lua_assert(a <= MAXARG_A && b <= MAXARG_Bx);
-  return luaK_code(fs, CREATE_ABx(o, a, b));
+  lua_assert(A <= MAXARG_A && b <= MAXARG_Bx);
+  return luaK_code(fs, CREATE_ABx(o, A, b));
 }
 
 
@@ -423,7 +431,7 @@ static int codeAsBx (FuncState *fs, OpCode o, int a, int bc) {
 ** Format and emit an 'isJ' instruction.
 */
 static int codesJ (FuncState *fs, OpCode o, int sj, int k) {
-  unsigned int j = sj + OFFSET_sJ;
+  unsigned int j = cast_uint(sj) + OFFSET_sJ;
   lua_assert(getOpMode(o) == isJ);
   lua_assert(j <= MAXARG_sJ && (k & ~1) == 0);
   return luaK_code(fs, CREATE_sJ(o, j, k));
@@ -433,9 +441,9 @@ static int codesJ (FuncState *fs, OpCode o, int sj, int k) {
 /*
 ** Emit an "extra argument" instruction (format 'iAx')
 */
-static int codeextraarg (FuncState *fs, int a) {
-  lua_assert(a <= MAXARG_Ax);
-  return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a));
+static int codeextraarg (FuncState *fs, int A) {
+  lua_assert(A <= MAXARG_Ax);
+  return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, A));
 }
 
 
@@ -1032,10 +1040,10 @@ static int exp2RK (FuncState *fs, expdesc *e) {
 }
 
 
-static void codeABRK (FuncState *fs, OpCode o, int a, int b,
+static void codeABRK (FuncState *fs, OpCode o, int A, int B,
                       expdesc *ec) {
   int k = exp2RK(fs, ec);
-  luaK_codeABCk(fs, o, a, b, ec->u.info, k);
+  luaK_codeABCk(fs, o, A, B, ec->u.info, k);
 }
 
 
@@ -1788,10 +1796,10 @@ void luaK_fixline (FuncState *fs, int line) {
 void luaK_settablesize (FuncState *fs, int pc, int ra, int asize, int hsize) {
   Instruction *inst = &fs->f->code[pc];
   int rb = (hsize != 0) ? luaO_ceillog2(hsize) + 1 : 0;  /* hash size */
-  int extra = asize / (MAXARG_C + 1);  /* higher bits of array size */
-  int rc = asize % (MAXARG_C + 1);  /* lower bits of array size */
+  int extra = asize / (MAXARG_vC + 1);  /* higher bits of array size */
+  int rc = asize % (MAXARG_vC + 1);  /* lower bits of array size */
   int k = (extra > 0);  /* true iff needs extra argument */
-  *inst = CREATE_ABCk(OP_NEWTABLE, ra, rb, rc, k);
+  *inst = CREATE_vABCk(OP_NEWTABLE, ra, rb, rc, k);
   *(inst + 1) = CREATE_Ax(OP_EXTRAARG, extra);
 }
 
@@ -1807,12 +1815,12 @@ void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
   lua_assert(tostore != 0);
   if (tostore == LUA_MULTRET)
     tostore = 0;
-  if (nelems <= MAXARG_C)
-    luaK_codeABC(fs, OP_SETLIST, base, tostore, nelems);
+  if (nelems <= MAXARG_vC)
+    luaK_codevABCk(fs, OP_SETLIST, base, tostore, nelems, 0);
   else {
-    int extra = nelems / (MAXARG_C + 1);
-    nelems %= (MAXARG_C + 1);
-    luaK_codeABCk(fs, OP_SETLIST, base, tostore, nelems, 1);
+    int extra = nelems / (MAXARG_vC + 1);
+    nelems %= (MAXARG_vC + 1);
+    luaK_codevABCk(fs, OP_SETLIST, base, tostore, nelems, 1);
     codeextraarg(fs, extra);
   }
   fs->freereg = base + 1;  /* free registers with list values */
@@ -1839,6 +1847,7 @@ static int finaltarget (Instruction *code, int i) {
 ** Do a final pass over the code of a function, doing small peephole
 ** optimizations and adjustments.
 */
+#include "lopnames.h"
 void luaK_finish (FuncState *fs) {
   int i;
   Proto *p = fs->f;

lcode.h

@@ -61,8 +61,10 @@ typedef enum UnOpr { OPR_MINUS, OPR_BNOT, OPR_NOT, OPR_LEN, OPR_NOUNOPR } UnOpr;
 
 LUAI_FUNC int luaK_code (FuncState *fs, Instruction i);
 LUAI_FUNC int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned Bx);
-LUAI_FUNC int luaK_codeABCk (FuncState *fs, OpCode o, int A,
-                                            int B, int C, int k);
+LUAI_FUNC int luaK_codeABCk (FuncState *fs, OpCode o, int A, int B, int C,
+                                            int k);
+LUAI_FUNC int luaK_codevABCk (FuncState *fs, OpCode o, int A, int B, int C,
+                                             int k);
 LUAI_FUNC int luaK_exp2const (FuncState *fs, const expdesc *e, TValue *v);
 LUAI_FUNC void luaK_fixline (FuncState *fs, int line);
 LUAI_FUNC void luaK_nil (FuncState *fs, int from, int n);

lopcodes.c

@@ -40,7 +40,7 @@ LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES] = {
  ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETTABLE */
  ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETI */
  ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETFIELD */
- ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_NEWTABLE */
+ ,opmode(0, 0, 0, 0, 1, ivABC)		/* OP_NEWTABLE */
  ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SELF */
  ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_ADDI */
  ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_ADDK */
@@ -99,7 +99,7 @@ LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES] = {
  ,opmode(0, 0, 0, 0, 0, iABx)		/* OP_TFORPREP */
  ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_TFORCALL */
  ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_TFORLOOP */
- ,opmode(0, 0, 1, 0, 0, iABC)		/* OP_SETLIST */
+ ,opmode(0, 0, 1, 0, 0, ivABC)		/* OP_SETLIST */
  ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_CLOSURE */
  ,opmode(0, 1, 0, 0, 1, iABC)		/* OP_VARARG */
  ,opmode(0, 0, 1, 0, 1, iABC)		/* OP_VARARGPREP */
@@ -127,6 +127,12 @@ int luaP_isOT (Instruction i) {
 ** it accepts multiple results.
 */
 int luaP_isIT (Instruction i) {
-  return testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0;
+  OpCode op = GET_OPCODE(i);
+  switch (op) {
+    case OP_SETLIST:
+      return testITMode(GET_OPCODE(i)) && GETARG_vB(i) == 0;
+    default:
+      return testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0;
+  }
 }
 

lopcodes.h

@@ -19,25 +19,30 @@
         3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
         1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
 iABC          C(8)     |      B(8)     |k|     A(8)      |   Op(7)     |
+ivABC         vC(10)     |     vB(6)   |k|     A(8)      |   Op(7)     |
 iABx                Bx(17)               |     A(8)      |   Op(7)     |
 iAsBx              sBx (signed)(17)      |     A(8)      |   Op(7)     |
 iAx                           Ax(25)                     |   Op(7)     |
 isJ                           sJ (signed)(25)            |   Op(7)     |
 
+  ('v' stands for "variant", 's' for "signed", 'x' for "extended".)
   A signed argument is represented in excess K: The represented value is
   the written unsigned value minus K, where K is half (rounded down) the
   maximum value for the corresponding unsigned argument.
 ===========================================================================*/
 
 
-enum OpMode {iABC, iABx, iAsBx, iAx, isJ};  /* basic instruction formats */
+/* basic instruction formats */
+enum OpMode {iABC, ivABC, iABx, iAsBx, iAx, isJ};
 
 
 /*
 ** size and position of opcode arguments.
 */
 #define SIZE_C		8
+#define SIZE_vC		10
 #define SIZE_B		8
+#define SIZE_vB		6
 #define SIZE_Bx		(SIZE_C + SIZE_B + 1)
 #define SIZE_A		8
 #define SIZE_Ax		(SIZE_Bx + SIZE_A)
@@ -50,7 +55,9 @@ enum OpMode {iABC, iABx, iAsBx, iAx, isJ};  /* basic instruction formats */
 #define POS_A		(POS_OP + SIZE_OP)
 #define POS_k		(POS_A + SIZE_A)
 #define POS_B		(POS_k + 1)
+#define POS_vB		(POS_k + 1)
 #define POS_C		(POS_B + SIZE_B)
+#define POS_vC		(POS_vB + SIZE_vB)
 
 #define POS_Bx		POS_k
 
@@ -95,7 +102,9 @@ enum OpMode {iABC, iABx, iAsBx, iAx, isJ};  /* basic instruction formats */
 
 #define MAXARG_A	((1<<SIZE_A)-1)
 #define MAXARG_B	((1<<SIZE_B)-1)
+#define MAXARG_vB	((1<<SIZE_vB)-1)
 #define MAXARG_C	((1<<SIZE_C)-1)
+#define MAXARG_vC	((1<<SIZE_vC)-1)
 #define OFFSET_sC	(MAXARG_C >> 1)
 
 #define int2sC(i)	((i) + OFFSET_sC)
@@ -126,16 +135,24 @@ enum OpMode {iABC, iABx, iAsBx, iAx, isJ};  /* basic instruction formats */
 #define GETARG_A(i)	getarg(i, POS_A, SIZE_A)
 #define SETARG_A(i,v)	setarg(i, v, POS_A, SIZE_A)
 
-#define GETARG_B(i)	check_exp(checkopm(i, iABC), getarg(i, POS_B, SIZE_B))
+#define GETARG_B(i)  \
+	check_exp(checkopm(i, iABC), getarg(i, POS_B, SIZE_B))
+#define GETARG_vB(i)  \
+	check_exp(checkopm(i, ivABC), getarg(i, POS_vB, SIZE_vB))
 #define GETARG_sB(i)	sC2int(GETARG_B(i))
 #define SETARG_B(i,v)	setarg(i, v, POS_B, SIZE_B)
+#define SETARG_vB(i,v)	setarg(i, v, POS_vB, SIZE_vB)
 
-#define GETARG_C(i)	check_exp(checkopm(i, iABC), getarg(i, POS_C, SIZE_C))
+#define GETARG_C(i)  \
+	check_exp(checkopm(i, iABC), getarg(i, POS_C, SIZE_C))
+#define GETARG_vC(i)  \
+	check_exp(checkopm(i, ivABC), getarg(i, POS_vC, SIZE_vC))
 #define GETARG_sC(i)	sC2int(GETARG_C(i))
 #define SETARG_C(i,v)	setarg(i, v, POS_C, SIZE_C)
+#define SETARG_vC(i,v)	setarg(i, v, POS_vC, SIZE_vC)
 
-#define TESTARG_k(i)	check_exp(checkopm(i, iABC), (cast_int(((i) & (1u << POS_k)))))
-#define GETARG_k(i)	check_exp(checkopm(i, iABC), getarg(i, POS_k, 1))
+#define TESTARG_k(i)	(cast_int(((i) & (1u << POS_k))))
+#define GETARG_k(i)	getarg(i, POS_k, 1)
 #define SETARG_k(i,v)	setarg(i, v, POS_k, 1)
 
 #define GETARG_Bx(i)	check_exp(checkopm(i, iABx), getarg(i, POS_Bx, SIZE_Bx))
@@ -160,6 +177,12 @@ enum OpMode {iABC, iABx, iAsBx, iAx, isJ};  /* basic instruction formats */
 			| (cast(Instruction, c)<<POS_C) \
 			| (cast(Instruction, k)<<POS_k))
 
+#define CREATE_vABCk(o,a,b,c,k)	((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_A) \
+			| (cast(Instruction, b)<<POS_vB) \
+			| (cast(Instruction, c)<<POS_vC) \
+			| (cast(Instruction, k)<<POS_k))
+
 #define CREATE_ABx(o,a,bc)	((cast(Instruction, o)<<POS_OP) \
 			| (cast(Instruction, a)<<POS_A) \
 			| (cast(Instruction, bc)<<POS_Bx))
@@ -306,7 +329,7 @@ OP_TFORPREP,/*	A Bx	create upvalue for R[A + 3]; pc+=Bx		*/
 OP_TFORCALL,/*	A C	R[A+4], ... ,R[A+3+C] := R[A](R[A+1], R[A+2]);	*/
 OP_TFORLOOP,/*	A Bx	if R[A+2] ~= nil then { R[A]=R[A+2]; pc -= Bx }	*/
 
-OP_SETLIST,/*	A B C k	R[A][C+i] := R[A+i], 1 <= i <= B		*/
+OP_SETLIST,/*	A vB vC k	R[A][vC+i] := R[A+i], 1 <= i <= vB	*/
 
 OP_CLOSURE,/*	A Bx	R[A] := closure(KPROTO[Bx])			*/
 

lparser.c

@@ -952,7 +952,7 @@ static void constructor (LexState *ls, expdesc *t) {
      sep -> ',' | ';' */
   FuncState *fs = ls->fs;
   int line = ls->linenumber;
-  int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
+  int pc = luaK_codevABCk(fs, OP_NEWTABLE, 0, 0, 0, 0);
   ConsControl cc;
   luaK_code(fs, 0);  /* space for extra arg. */
   cc.na = cc.nh = cc.tostore = 0;

ltests.c

@@ -697,6 +697,11 @@ static char *buildop (Proto *p, int pc, char *buff) {
               GETARG_A(i), GETARG_B(i), GETARG_C(i),
               GETARG_k(i) ? " (k)" : "");
       break;
+    case ivABC:
+      sprintf(buff, "%-12s%4d %4d %4d%s", name,
+              GETARG_A(i), GETARG_vB(i), GETARG_vC(i),
+              GETARG_k(i) ? " (k)" : "");
+      break;
     case iABx:
       sprintf(buff, "%-12s%4d %4d", name, GETARG_A(i), GETARG_Bx(i));
       break;

lvm.c

@@ -1359,14 +1359,15 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
       }
       vmcase(OP_NEWTABLE) {
         StkId ra = RA(i);
-        int b = GETARG_B(i);  /* log2(hash size) + 1 */
-        int c = GETARG_C(i);  /* array size */
+        int b = GETARG_vB(i);  /* log2(hash size) + 1 */
+        int c = GETARG_vC(i);  /* array size */
         Table *t;
         if (b > 0)
-          b = 1 << (b - 1);  /* size is 2^(b - 1) */
-        lua_assert((!TESTARG_k(i)) == (GETARG_Ax(*pc) == 0));
-        if (TESTARG_k(i))  /* non-zero extra argument? */
-          c += GETARG_Ax(*pc) * (MAXARG_C + 1);  /* add it to size */
+          b = 1 << (b - 1);  /* hash size is 2^(b - 1) */
+        if (TESTARG_k(i)) {  /* non-zero extra argument? */
+          lua_assert(GETARG_Ax(*pc) != 0);
+          c += GETARG_Ax(*pc) * (MAXARG_vC + 1);  /* add it to array size */
+        }
         pc++;  /* skip extra argument */
         L->top.p = ra + 1;  /* correct top in case of emergency GC */
         t = luaH_new(L);  /* memory allocation */
@@ -1850,8 +1851,8 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
       }}
       vmcase(OP_SETLIST) {
         StkId ra = RA(i);
-        int n = GETARG_B(i);
-        unsigned int last = GETARG_C(i);
+        int n = GETARG_vB(i);
+        unsigned int last = GETARG_vC(i);
         Table *h = hvalue(s2v(ra));
         if (n == 0)
           n = cast_int(L->top.p - ra) - 1;  /* get up to the top */
@@ -1859,11 +1860,15 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
           L->top.p = ci->top.p;  /* correct top in case of emergency GC */
         last += n;
         if (TESTARG_k(i)) {
-          last += GETARG_Ax(*pc) * (MAXARG_C + 1);
+          last += GETARG_Ax(*pc) * (MAXARG_vC + 1);
           pc++;
         }
-        if (last > luaH_realasize(h))  /* needs more space? */
+        /* when 'n' is known, table should have proper size */
+        if (last > luaH_realasize(h)) {  /* needs more space? */
+          /* fixed-size sets should have space preallocated */
+          lua_assert(GETARG_vB(i) == 0);
           luaH_resizearray(L, h, last);  /* preallocate it at once */
+        }
         for (; n > 0; n--) {
           TValue *val = s2v(ra + n);
           obj2arr(h, last - 1, val);