Initial import

third_party/duktape/duk_hcompfunc.h

@@ -0,0 +1,273 @@
+/*
+ *  Heap compiled function (ECMAScript function) representation.
+ *
+ *  There is a single data buffer containing the ECMAScript function's
+ *  bytecode, constants, and inner functions.
+ */
+
+#if !defined(DUK_HCOMPFUNC_H_INCLUDED)
+#define DUK_HCOMPFUNC_H_INCLUDED
+
+/*
+ *  Field accessor macros
+ */
+
+/* XXX: casts could be improved, especially for GET/SET DATA */
+
+#if defined(DUK_USE_HEAPPTR16)
+#define DUK_HCOMPFUNC_GET_DATA(heap,h) \
+	((duk_hbuffer_fixed *) (void *) DUK_USE_HEAPPTR_DEC16((heap)->heap_udata, (h)->data16))
+#define DUK_HCOMPFUNC_SET_DATA(heap,h,v) do { \
+		(h)->data16 = DUK_USE_HEAPPTR_ENC16((heap)->heap_udata, (void *) (v)); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_FUNCS(heap,h)  \
+	((duk_hobject **) (void *) (DUK_USE_HEAPPTR_DEC16((heap)->heap_udata, (h)->funcs16)))
+#define DUK_HCOMPFUNC_SET_FUNCS(heap,h,v)  do { \
+		(h)->funcs16 = DUK_USE_HEAPPTR_ENC16((heap)->heap_udata, (void *) (v)); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_BYTECODE(heap,h)  \
+	((duk_instr_t *) (void *) (DUK_USE_HEAPPTR_DEC16((heap)->heap_udata, (h)->bytecode16)))
+#define DUK_HCOMPFUNC_SET_BYTECODE(heap,h,v)  do { \
+		(h)->bytecode16 = DUK_USE_HEAPPTR_ENC16((heap)->heap_udata, (void *) (v)); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_LEXENV(heap,h)  \
+	((duk_hobject *) (void *) (DUK_USE_HEAPPTR_DEC16((heap)->heap_udata, (h)->lex_env16)))
+#define DUK_HCOMPFUNC_SET_LEXENV(heap,h,v)  do { \
+		(h)->lex_env16 = DUK_USE_HEAPPTR_ENC16((heap)->heap_udata, (void *) (v)); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_VARENV(heap,h)  \
+	((duk_hobject *) (void *) (DUK_USE_HEAPPTR_DEC16((heap)->heap_udata, (h)->var_env16)))
+#define DUK_HCOMPFUNC_SET_VARENV(heap,h,v)  do { \
+		(h)->var_env16 = DUK_USE_HEAPPTR_ENC16((heap)->heap_udata, (void *) (v)); \
+	} while (0)
+#else
+#define DUK_HCOMPFUNC_GET_DATA(heap,h)  ((duk_hbuffer_fixed *) (void *) (h)->data)
+#define DUK_HCOMPFUNC_SET_DATA(heap,h,v) do { \
+		(h)->data = (duk_hbuffer *) (v); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_FUNCS(heap,h)  ((h)->funcs)
+#define DUK_HCOMPFUNC_SET_FUNCS(heap,h,v)  do { \
+		(h)->funcs = (v); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_BYTECODE(heap,h)  ((h)->bytecode)
+#define DUK_HCOMPFUNC_SET_BYTECODE(heap,h,v)  do { \
+		(h)->bytecode = (v); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_LEXENV(heap,h)  ((h)->lex_env)
+#define DUK_HCOMPFUNC_SET_LEXENV(heap,h,v)  do { \
+		(h)->lex_env = (v); \
+	} while (0)
+#define DUK_HCOMPFUNC_GET_VARENV(heap,h)  ((h)->var_env)
+#define DUK_HCOMPFUNC_SET_VARENV(heap,h,v)  do { \
+		(h)->var_env = (v); \
+	} while (0)
+#endif
+
+/*
+ *  Accessor macros for function specific data areas
+ */
+
+/* Note: assumes 'data' is always a fixed buffer */
+#define DUK_HCOMPFUNC_GET_BUFFER_BASE(heap,h)  \
+	DUK_HBUFFER_FIXED_GET_DATA_PTR((heap), DUK_HCOMPFUNC_GET_DATA((heap), (h)))
+
+#define DUK_HCOMPFUNC_GET_CONSTS_BASE(heap,h)  \
+	((duk_tval *) (void *) DUK_HCOMPFUNC_GET_BUFFER_BASE((heap), (h)))
+
+#define DUK_HCOMPFUNC_GET_FUNCS_BASE(heap,h)  \
+	DUK_HCOMPFUNC_GET_FUNCS((heap), (h))
+
+#define DUK_HCOMPFUNC_GET_CODE_BASE(heap,h)  \
+	DUK_HCOMPFUNC_GET_BYTECODE((heap), (h))
+
+#define DUK_HCOMPFUNC_GET_CONSTS_END(heap,h)  \
+	((duk_tval *) (void *) DUK_HCOMPFUNC_GET_FUNCS((heap), (h)))
+
+#define DUK_HCOMPFUNC_GET_FUNCS_END(heap,h)  \
+	((duk_hobject **) (void *) DUK_HCOMPFUNC_GET_BYTECODE((heap), (h)))
+
+/* XXX: double evaluation of DUK_HCOMPFUNC_GET_DATA() */
+#define DUK_HCOMPFUNC_GET_CODE_END(heap,h)  \
+	((duk_instr_t *) (void *) (DUK_HBUFFER_FIXED_GET_DATA_PTR((heap), DUK_HCOMPFUNC_GET_DATA((heap), (h))) + \
+	                DUK_HBUFFER_GET_SIZE((duk_hbuffer *) DUK_HCOMPFUNC_GET_DATA((heap), h))))
+
+#define DUK_HCOMPFUNC_GET_CONSTS_SIZE(heap,h)  \
+	( \
+	 (duk_size_t) \
+	 ( \
+	   ((const duk_uint8_t *) DUK_HCOMPFUNC_GET_CONSTS_END((heap), (h))) - \
+	   ((const duk_uint8_t *) DUK_HCOMPFUNC_GET_CONSTS_BASE((heap), (h))) \
+	 ) \
+	)
+
+#define DUK_HCOMPFUNC_GET_FUNCS_SIZE(heap,h)  \
+	( \
+	 (duk_size_t) \
+	 ( \
+	   ((const duk_uint8_t *) DUK_HCOMPFUNC_GET_FUNCS_END((heap), (h))) - \
+	   ((const duk_uint8_t *) DUK_HCOMPFUNC_GET_FUNCS_BASE((heap), (h))) \
+	 ) \
+	)
+
+#define DUK_HCOMPFUNC_GET_CODE_SIZE(heap,h)  \
+	( \
+	 (duk_size_t) \
+	 ( \
+	   ((const duk_uint8_t *) DUK_HCOMPFUNC_GET_CODE_END((heap),(h))) - \
+	   ((const duk_uint8_t *) DUK_HCOMPFUNC_GET_CODE_BASE((heap),(h))) \
+	 ) \
+	)
+
+#define DUK_HCOMPFUNC_GET_CONSTS_COUNT(heap,h)  \
+	((duk_size_t) (DUK_HCOMPFUNC_GET_CONSTS_SIZE((heap), (h)) / sizeof(duk_tval)))
+
+#define DUK_HCOMPFUNC_GET_FUNCS_COUNT(heap,h)  \
+	((duk_size_t) (DUK_HCOMPFUNC_GET_FUNCS_SIZE((heap), (h)) / sizeof(duk_hobject *)))
+
+#define DUK_HCOMPFUNC_GET_CODE_COUNT(heap,h)  \
+	((duk_size_t) (DUK_HCOMPFUNC_GET_CODE_SIZE((heap), (h)) / sizeof(duk_instr_t)))
+
+/*
+ *  Validity assert
+ */
+
+#if defined(DUK_USE_ASSERTIONS)
+DUK_INTERNAL_DECL void duk_hcompfunc_assert_valid(duk_hcompfunc *h);
+#define DUK_HCOMPFUNC_ASSERT_VALID(h)  do { duk_hcompfunc_assert_valid((h)); } while (0)
+#else
+#define DUK_HCOMPFUNC_ASSERT_VALID(h)  do {} while (0)
+#endif
+
+/*
+ *  Main struct
+ */
+
+struct duk_hcompfunc {
+	/* shared object part */
+	duk_hobject obj;
+
+	/*
+	 *  Pointers to function data area for faster access.  Function
+	 *  data is a buffer shared between all closures of the same
+	 *  "template" function.  The data buffer is always fixed (non-
+	 *  dynamic, hence stable), with a layout as follows:
+	 *
+	 *    constants (duk_tval)
+	 *    inner functions (duk_hobject *)
+	 *    bytecode (duk_instr_t)
+	 *
+	 *  Note: bytecode end address can be computed from 'data' buffer
+	 *  size.  It is not strictly necessary functionally, assuming
+	 *  bytecode never jumps outside its allocated area.  However,
+	 *  it's a safety/robustness feature for avoiding the chance of
+	 *  executing random data as bytecode due to a compiler error.
+	 *
+	 *  Note: values in the data buffer must be incref'd (they will
+	 *  be decref'd on release) for every compiledfunction referring
+	 *  to the 'data' element.
+	 */
+
+	/* Data area, fixed allocation, stable data ptrs. */
+#if defined(DUK_USE_HEAPPTR16)
+	duk_uint16_t data16;
+#else
+	duk_hbuffer *data;
+#endif
+
+	/* No need for constants pointer (= same as data).
+	 *
+	 * When using 16-bit packing alignment to 4 is nice.  'funcs' will be
+	 * 4-byte aligned because 'constants' are duk_tvals.  For now the
+	 * inner function pointers are not compressed, so that 'bytecode' will
+	 * also be 4-byte aligned.
+	 */
+#if defined(DUK_USE_HEAPPTR16)
+	duk_uint16_t funcs16;
+	duk_uint16_t bytecode16;
+#else
+	duk_hobject **funcs;
+	duk_instr_t *bytecode;
+#endif
+
+	/* Lexenv: lexical environment of closure, NULL for templates.
+	 * Varenv: variable environment of closure, NULL for templates.
+	 */
+#if defined(DUK_USE_HEAPPTR16)
+	duk_uint16_t lex_env16;
+	duk_uint16_t var_env16;
+#else
+	duk_hobject *lex_env;
+	duk_hobject *var_env;
+#endif
+
+	/*
+	 *  'nregs' registers are allocated on function entry, at most 'nargs'
+	 *  are initialized to arguments, and the rest to undefined.  Arguments
+	 *  above 'nregs' are not mapped to registers.  All registers in the
+	 *  active stack range must be initialized because they are GC reachable.
+	 *  'nargs' is needed so that if the function is given more than 'nargs'
+	 *  arguments, the additional arguments do not 'clobber' registers
+	 *  beyond 'nregs' which must be consistently initialized to undefined.
+	 *
+	 *  Usually there is no need to know which registers are mapped to
+	 *  local variables.  Registers may be allocated to variable in any
+	 *  way (even including gaps).  However, a register-variable mapping
+	 *  must be the same for the duration of the function execution and
+	 *  the register cannot be used for anything else.
+	 *
+	 *  When looking up variables by name, the '_Varmap' map is used.
+	 *  When an activation closes, registers mapped to arguments are
+	 *  copied into the environment record based on the same map.  The
+	 *  reverse map (from register to variable) is not currently needed
+	 *  at run time, except for debugging, so it is not maintained.
+	 */
+
+	duk_uint16_t nregs;                /* regs to allocate */
+	duk_uint16_t nargs;                /* number of arguments allocated to regs */
+
+	/*
+	 *  Additional control information is placed into the object itself
+	 *  as internal properties to avoid unnecessary fields for the
+	 *  majority of functions.  The compiler tries to omit internal
+	 *  control fields when possible.
+	 *
+	 *  Function templates:
+	 *
+	 *    {
+	 *      name: "func",    // declaration, named function expressions
+	 *      fileName: <debug info for creating nice errors>
+	 *      _Varmap: { "arg1": 0, "arg2": 1, "varname": 2 },
+	 *      _Formals: [ "arg1", "arg2" ],
+	 *      _Source: "function func(arg1, arg2) { ... }",
+	 *      _Pc2line: <debug info for pc-to-line mapping>,
+	 *    }
+	 *
+	 *  Function instances:
+	 *
+	 *    {
+	 *      length: 2,
+	 *      prototype: { constructor: <func> },
+	 *      caller: <thrower>,
+	 *      arguments: <thrower>,
+	 *      name: "func",    // declaration, named function expressions
+	 *      fileName: <debug info for creating nice errors>
+	 *      _Varmap: { "arg1": 0, "arg2": 1, "varname": 2 },
+	 *      _Formals: [ "arg1", "arg2" ],
+	 *      _Source: "function func(arg1, arg2) { ... }",
+	 *      _Pc2line: <debug info for pc-to-line mapping>,
+	 *    }
+	 *
+	 *  More detailed description of these properties can be found
+	 *  in the documentation.
+	 */
+
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+	/* Line number range for function.  Needed during debugging to
+	 * determine active breakpoints.
+	 */
+	duk_uint32_t start_line;
+	duk_uint32_t end_line;
+#endif
+};
+
+#endif  /* DUK_HCOMPFUNC_H_INCLUDED */