new implementation for the Virtual Machine

1 files changed, 5 insertions, 84 deletions

diff --git a/llimits.h b/llimits.h
index 51dbe7af..2b288981 100644
--- a/llimits.h
+++ b/llimits.h
@@ -1,5 +1,5 @@
 /*
-** $Id: llimits.h,v 1.27 2001/02/23 20:28:56 roberto Exp roberto $
+** $Id: llimits.h,v 1.28 2001/03/26 14:31:49 roberto Exp roberto $
 ** Limits, basic types, and some other `installation-dependent' definitions
 ** See Copyright Notice in lua.h
 */
@@ -89,92 +89,23 @@ union L_Umaxalign { double d; void *s; long l; };
 /*
 ** type for virtual-machine instructions
 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
-** For a very small machine, you may change that to 2 bytes (and adjust
-** the following limits accordingly)
 */
 typedef unsigned long Instruction;
 
 
-/*
-** size and position of opcode arguments.
-** For an instruction with 2 bytes, size is 16, and size_b can be 5
-** (accordingly, size_u will be 10, and size_a will be 5)
-*/
-#define SIZE_INSTRUCTION        32
-#define SIZE_B          8
-
-#define SIZE_OP         6
-#define SIZE_U          (SIZE_INSTRUCTION-SIZE_OP)
-#define POS_U           SIZE_OP
-#define POS_B           SIZE_OP
-#define SIZE_A          (SIZE_INSTRUCTION-(SIZE_OP+SIZE_B))
-#define POS_A           (SIZE_OP+SIZE_B)
-
-
-/*
-** limits for opcode arguments.
-** we use (signed) int to manipulate most arguments,
-** so they must fit in BITS_INT-1 bits (-1 for sign)
-*/
-#if SIZE_U < BITS_INT-1
-#define MAXARG_U        ((1<<SIZE_U)-1)
-#define MAXARG_S        (MAXARG_U>>1)           /* `S' is signed */
-#else
-#define MAXARG_U        MAX_INT
-#define MAXARG_S        MAX_INT
-#endif
-
-#if SIZE_A < BITS_INT-1
-#define MAXARG_A        ((1<<SIZE_A)-1)
-#else
-#define MAXARG_A        MAX_INT
-#endif
-
-#if SIZE_B < BITS_INT-1
-#define MAXARG_B        ((1<<SIZE_B)-1)
-#else
-#define MAXARG_B        MAX_INT
-#endif
-
-
-/* maximum stack size in a function */
-#ifndef MAXSTACK
+/* maximum stack for a Lua function */
 #define MAXSTACK        250
-#endif
-
-#if MAXSTACK > MAXARG_B
-#undef MAXSTACK
-#define MAXSTACK        MAXARG_B
-#endif
 
 
 /* maximum number of local variables */
 #ifndef MAXLOCALS
 #define MAXLOCALS 200           /* arbitrary limit (<MAXSTACK) */
 #endif
-#if MAXLOCALS>=MAXSTACK
-#undef MAXLOCALS
-#define MAXLOCALS       (MAXSTACK-1)
-#endif
 
 
 /* maximum number of upvalues */
 #ifndef MAXUPVALUES
-#define MAXUPVALUES 32          /* arbitrary limit (<=MAXARG_B) */
-#endif
-#if MAXUPVALUES>MAXARG_B
-#undef MAXUPVALUES
-#define MAXUPVALUES     MAXARG_B
-#endif
-
-
-/* maximum number of variables in the left side of an assignment */
-#ifndef MAXVARSLH
-#define MAXVARSLH 100           /* arbitrary limit (<MULT_RET) */
-#endif
-#if MAXVARSLH>=MULT_RET
-#undef MAXVARSLH
-#define MAXVARSLH       (MULT_RET-1)
+#define MAXUPVALUES 32          /* arbitrary limit (<MAXSTACK) */
 #endif
 
 
@@ -182,27 +113,17 @@ typedef unsigned long Instruction;
 #ifndef MAXPARAMS
 #define MAXPARAMS 100           /* arbitrary limit (<MAXLOCALS) */
 #endif
-#if MAXPARAMS>=MAXLOCALS
-#undef MAXPARAMS
-#define MAXPARAMS       (MAXLOCALS-1)
-#endif
 
 
 /* number of list items to accumulate before a SETLIST instruction */
+/* (must be a power of 2) */
 #define LFIELDS_PER_FLUSH       64
-#if LFIELDS_PER_FLUSH>(MAXSTACK/4)
-#undef LFIELDS_PER_FLUSH
-#define LFIELDS_PER_FLUSH       (MAXSTACK/4)
-#endif
 
-/* number of record items to accumulate before a SETMAP instruction */
-/* (each item counts 2 elements on the stack: an index and a value) */
-#define RFIELDS_PER_FLUSH       (LFIELDS_PER_FLUSH/2)
 
 
 /* maximum lookback to find a real constant (for code generation) */
 #ifndef LOOKBACKNUMS
-#define LOOKBACKNUMS    20      /* arbitrary constant */
+#define LOOKBACKNUMS    40      /* arbitrary constant */
 #endif