/* ScummVM - Graphic Adventure Engine * * ScummVM is the legal property of its developers, whose names * are too numerous to list here. Please refer to the COPYRIGHT * file distributed with this source distribution. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * $URL$ * $Id$ * */ #ifndef SCI_ENGINE_VM_H #define SCI_ENGINE_VM_H /* VM and kernel declarations */ #include "sci/engine/vm_types.h" // for reg_t #include "sci/resource.h" // for SciVersion #include "common/util.h" namespace Sci { class SegManager; struct EngineState; class Object; class ResourceManager; /** Number of bytes to be allocated for the stack */ #define VM_STACK_SIZE 0x1000 /** Magical object identifier */ #define SCRIPT_OBJECT_MAGIC_NUMBER 0x1234 /** Offset of this identifier */ #define SCRIPT_OBJECT_MAGIC_OFFSET (getSciVersion() < SCI_VERSION_1_1 ? -8 : 0) /** Stack pointer value: Use predecessor's value */ #define CALL_SP_CARRY NULL /** Types of selectors as returned by lookupSelector() below. */ enum SelectorType { kSelectorNone = 0, kSelectorVariable, kSelectorMethod }; struct Class { int script; ///< number of the script the class is in, -1 for non-existing reg_t reg; ///< offset; script-relative offset, segment: 0 if not instantiated }; #define RAW_IS_OBJECT(datablock) (READ_SCI11ENDIAN_UINT16(((byte *) datablock) + SCRIPT_OBJECT_MAGIC_OFFSET) == SCRIPT_OBJECT_MAGIC_NUMBER) // A reference to an object's variable. // The object is stored as a reg_t, the variable as an index into _variables struct ObjVarRef { reg_t obj; int varindex; reg_t* getPointer(SegManager *segMan) const; }; enum ExecStackType { EXEC_STACK_TYPE_CALL = 0, EXEC_STACK_TYPE_KERNEL = 1, EXEC_STACK_TYPE_VARSELECTOR = 2 }; struct ExecStack { reg_t objp; ///< Pointer to the beginning of the current object reg_t sendp; ///< Pointer to the object containing the invoked method union { ObjVarRef varp; // Variable pointer for r/w access reg_t pc; // Pointer to the initial program counter. Not accurate for the TOS element } addr; StackPtr fp; // Frame pointer StackPtr sp; // Stack pointer int argc; StackPtr variables_argp; // Argument pointer SegmentId local_segment; // local variables etc Selector selector; // The selector which was used to call or -1 if not applicable int exportId; // The exportId which was called or -1 if not applicable int localCallOffset; // Local call offset or -1 if not applicable int origin; // The stack frame position the call was made from, or -1 if it was the initial call ExecStackType type; reg_t* getVarPointer(SegManager *segMan) const; }; enum { VAR_GLOBAL = 0, VAR_LOCAL = 1, VAR_TEMP = 2, VAR_PARAM = 3 }; /** Number of kernel calls in between gcs; should be < 50000 */ enum { GC_INTERVAL = 32768 }; // Opcode formats enum opcode_format { Script_Invalid = -1, Script_None = 0, Script_Byte, Script_SByte, Script_Word, Script_SWord, Script_Variable, Script_SVariable, Script_SRelative, Script_Property, Script_Global, Script_Local, Script_Temp, Script_Param, Script_Offset, Script_End }; enum sci_opcodes { op_bnot = 0x00, // 000 op_add = 0x01, // 001 op_sub = 0x02, // 002 op_mul = 0x03, // 003 op_div = 0x04, // 004 op_mod = 0x05, // 005 op_shr = 0x06, // 006 op_shl = 0x07, // 007 op_xor = 0x08, // 008 op_and = 0x09, // 009 op_or = 0x0a, // 010 op_neg = 0x0b, // 011 op_not = 0x0c, // 012 op_eq_ = 0x0d, // 013 op_ne_ = 0x0e, // 014 op_gt_ = 0x0f, // 015 op_ge_ = 0x10, // 016 op_lt_ = 0x11, // 017 op_le_ = 0x12, // 018 op_ugt_ = 0x13, // 019 op_uge_ = 0x14, // 020 op_ult_ = 0x15, // 021 op_ule_ = 0x16, // 022 op_bt = 0x17, // 023 op_bnt = 0x18, // 024 op_jmp = 0x19, // 025 op_ldi = 0x1a, // 026 op_push = 0x1b, // 027 op_pushi = 0x1c, // 028 op_toss = 0x1d, // 029 op_dup = 0x1e, // 030 op_link = 0x1f, // 031 op_call = 0x20, // 032 op_callk = 0x21, // 033 op_callb = 0x22, // 034 op_calle = 0x23, // 035 op_ret = 0x24, // 036 op_send = 0x25, // 037 // dummy 0x26, // 038 // dummy 0x27, // 039 op_class = 0x28, // 040 // dummy 0x29, // 041 op_self = 0x2a, // 042 op_super = 0x2b, // 043 op_rest = 0x2c, // 044 op_lea = 0x2d, // 045 op_selfID = 0x2e, // 046 // dummy 0x2f // 047 op_pprev = 0x30, // 048 op_pToa = 0x31, // 049 op_aTop = 0x32, // 050 op_pTos = 0x33, // 051 op_sTop = 0x34, // 052 op_ipToa = 0x35, // 053 op_dpToa = 0x36, // 054 op_ipTos = 0x37, // 055 op_dpTos = 0x38, // 056 op_lofsa = 0x39, // 057 op_lofss = 0x3a, // 058 op_push0 = 0x3b, // 059 op_push1 = 0x3c, // 060 op_push2 = 0x3d, // 061 op_pushSelf = 0x3e, // 062 op_line = 0x3f, // 063 op_lag = 0x40, // 064 op_lal = 0x41, // 065 op_lat = 0x42, // 066 op_lap = 0x43, // 067 op_lsg = 0x44, // 068 op_lsl = 0x45, // 069 op_lst = 0x46, // 070 op_lsp = 0x47, // 071 op_lagi = 0x48, // 072 op_lali = 0x49, // 073 op_lati = 0x4a, // 074 op_lapi = 0x4b, // 075 op_lsgi = 0x4c, // 076 op_lsli = 0x4d, // 077 op_lsti = 0x4e, // 078 op_lspi = 0x4f, // 079 op_sag = 0x50, // 080 op_sal = 0x51, // 081 op_sat = 0x52, // 082 op_sap = 0x53, // 083 op_ssg = 0x54, // 084 op_ssl = 0x55, // 085 op_sst = 0x56, // 086 op_ssp = 0x57, // 087 op_sagi = 0x58, // 088 op_sali = 0x59, // 089 op_sati = 0x5a, // 090 op_sapi = 0x5b, // 091 op_ssgi = 0x5c, // 092 op_ssli = 0x5d, // 093 op_ssti = 0x5e, // 094 op_sspi = 0x5f, // 095 op_plusag = 0x60, // 096 op_plusal = 0x61, // 097 op_plusat = 0x62, // 098 op_plusap = 0x63, // 099 op_plussg = 0x64, // 100 op_plussl = 0x65, // 101 op_plusst = 0x66, // 102 op_plussp = 0x67, // 103 op_plusagi = 0x68, // 104 op_plusali = 0x69, // 105 op_plusati = 0x6a, // 106 op_plusapi = 0x6b, // 107 op_plussgi = 0x6c, // 108 op_plussli = 0x6d, // 109 op_plussti = 0x6e, // 110 op_plusspi = 0x6f, // 111 op_minusag = 0x70, // 112 op_minusal = 0x71, // 113 op_minusat = 0x72, // 114 op_minusap = 0x73, // 115 op_minussg = 0x74, // 116 op_minussl = 0x75, // 117 op_minusst = 0x76, // 118 op_minussp = 0x77, // 119 op_minusagi = 0x78, // 120 op_minusali = 0x79, // 121 op_minusati = 0x7a, // 122 op_minusapi = 0x7b, // 123 op_minussgi = 0x7c, // 124 op_minussli = 0x7d, // 125 op_minussti = 0x7e, // 126 op_minusspi = 0x7f // 127 }; extern opcode_format g_opcode_formats[128][4]; void script_adjust_opcode_formats(); /** * Executes function pubfunct of the specified script. * @param[in] s The state which is to be executed with * @param[in] script The script which is called * @param[in] pubfunct The exported script function which is to * be called * @param[in] sp Stack pointer position * @param[in] calling_obj The heap address of the object that * executed the call * @param[in] argc Number of arguments supplied * @param[in] argp Pointer to the first supplied argument * @return A pointer to the new exec stack TOS entry */ ExecStack *execute_method(EngineState *s, uint16 script, uint16 pubfunct, StackPtr sp, reg_t calling_obj, uint16 argc, StackPtr argp); /** * Executes a "send" or related operation to a selector. * @param[in] s The EngineState to operate on * @param[in] send_obj Heap address of the object to send to * @param[in] work_obj Heap address of the object initiating the send * @param[in] sp Stack pointer position * @param[in] framesize Size of the send as determined by the "send" * operation * @param[in] argp Pointer to the beginning of the heap block * containing the data to be sent. This area is a * succession of one or more sequences of * [selector_number][argument_counter] and then * "argument_counter" word entries with the * parameter values. * @return A pointer to the new execution stack TOS entry */ ExecStack *send_selector(EngineState *s, reg_t send_obj, reg_t work_obj, StackPtr sp, int framesize, StackPtr argp); /** * This function executes SCI bytecode * It executes the code on s->heap[pc] until it hits a 'ret' operation * while (stack_base == stack_pos). Requires s to be set up correctly. * @param[in] s The state to use * @param[in] restoring true if s has just been restored, false otherwise */ void run_vm(EngineState *s, bool restoring); /** * Debugger functionality * @param[in] s The state at which debugging should take place */ void script_debug(EngineState *s); /** * Looks up a selector and returns its type and value * varindex is written to iff it is non-NULL and the selector indicates a property of the object. * @param[in] segMan The Segment Manager * @param[in] obj Address of the object to look the selector up in * @param[in] selectorid The selector to look up * @param[out] varp A reference to the selector, if it is a * variable. * @param[out] fptr A reference to the function described by that * selector, if it is a valid function selector. * fptr is written to iff it is non-NULL and the * selector indicates a member function of that * object. * @return kSelectorNone if the selector was not found in * the object or its superclasses. * kSelectorVariable if the selector represents an * object-relative variable. * kSelectorMethod if the selector represents a * method */ SelectorType lookupSelector(SegManager *segMan, reg_t obj, Selector selectorid, ObjVarRef *varp, reg_t *fptr); /** * Read a PMachine instruction from a memory buffer and return its length. * * @param[in] src address from which to start parsing * @param[out] extOpcode "extended" opcode of the parsed instruction * @param[out] opparams parameter for the parsed instruction * @return the length in bytes of the instruction * * @todo How about changing opparams from int16 to int / int32 to preserve * unsigned 16bit words as read for Script_Word? In the past, this * was irrelevant as only a debug opcode used Script_Word. But with * SCI32 we are now using Script_Word for more opcodes. Maybe this is * just a mistake and those opcodes should used Script_SWord -- but if * not then we definitely should change this to int, else we might run * into trouble if we encounter high value words. *If* those exist at all. */ int readPMachineInstruction(const byte *src, byte &extOpcode, int16 opparams[4]); } // End of namespace Sci #endif // SCI_ENGINE_VM_H