1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/graphite2/src/inc/Machine.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,197 @@
1.4 +/* GRAPHITE2 LICENSING
1.5 +
1.6 + Copyright 2010, SIL International
1.7 + All rights reserved.
1.8 +
1.9 + This library is free software; you can redistribute it and/or modify
1.10 + it under the terms of the GNU Lesser General Public License as published
1.11 + by the Free Software Foundation; either version 2.1 of License, or
1.12 + (at your option) any later version.
1.13 +
1.14 + This program is distributed in the hope that it will be useful,
1.15 + but WITHOUT ANY WARRANTY; without even the implied warranty of
1.16 + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1.17 + Lesser General Public License for more details.
1.18 +
1.19 + You should also have received a copy of the GNU Lesser General Public
1.20 + License along with this library in the file named "LICENSE".
1.21 + If not, write to the Free Software Foundation, 51 Franklin Street,
1.22 + Suite 500, Boston, MA 02110-1335, USA or visit their web page on the
1.23 + internet at http://www.fsf.org/licenses/lgpl.html.
1.24 +
1.25 +Alternatively, the contents of this file may be used under the terms of the
1.26 +Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public
1.27 +License, as published by the Free Software Foundation, either version 2
1.28 +of the License or (at your option) any later version.
1.29 +*/
1.30 +// This general interpreter interface.
1.31 +// Author: Tim Eves
1.32 +
1.33 +// Build one of direct_machine.cpp or call_machine.cpp to implement this
1.34 +// interface.
1.35 +
1.36 +#pragma once
1.37 +#include <cstring>
1.38 +#include <graphite2/Types.h>
1.39 +#include "inc/Main.h"
1.40 +
1.41 +#if defined(__GNUC__)
1.42 +#if defined(__clang__) || (__GNUC__ * 100 + __GNUC_MINOR__ * 10) < 430
1.43 +#define HOT
1.44 +#if defined(__x86_64)
1.45 +#define REGPARM(n) __attribute__((regparm(n)))
1.46 +#else
1.47 +#define REGPARM(n)
1.48 +#endif
1.49 +#else
1.50 +#define HOT __attribute__((hot))
1.51 +#if defined(__x86_64)
1.52 +#define REGPARM(n) __attribute__((hot, regparm(n)))
1.53 +#else
1.54 +#define REGPARM(n)
1.55 +#endif
1.56 +#endif
1.57 +#else
1.58 +#define HOT
1.59 +#define REGPARM(n)
1.60 +#endif
1.61 +
1.62 +namespace graphite2 {
1.63 +
1.64 +// Forward declarations
1.65 +class Segment;
1.66 +class Slot;
1.67 +class SlotMap;
1.68 +
1.69 +
1.70 +namespace vm
1.71 +{
1.72 +
1.73 +
1.74 +typedef void * instr;
1.75 +typedef Slot * slotref;
1.76 +
1.77 +enum {VARARGS = 0xff, MAX_NAME_LEN=32};
1.78 +
1.79 +enum opcode {
1.80 + NOP = 0,
1.81 +
1.82 + PUSH_BYTE, PUSH_BYTEU, PUSH_SHORT, PUSH_SHORTU, PUSH_LONG,
1.83 +
1.84 + ADD, SUB, MUL, DIV,
1.85 + MIN_, MAX_,
1.86 + NEG,
1.87 + TRUNC8, TRUNC16,
1.88 +
1.89 + COND,
1.90 +
1.91 + AND, OR, NOT,
1.92 + EQUAL, NOT_EQ,
1.93 + LESS, GTR, LESS_EQ, GTR_EQ,
1.94 +
1.95 + NEXT, NEXT_N, COPY_NEXT,
1.96 + PUT_GLYPH_8BIT_OBS, PUT_SUBS_8BIT_OBS, PUT_COPY,
1.97 + INSERT, DELETE,
1.98 + ASSOC,
1.99 + CNTXT_ITEM,
1.100 +
1.101 + ATTR_SET, ATTR_ADD, ATTR_SUB,
1.102 + ATTR_SET_SLOT,
1.103 + IATTR_SET_SLOT,
1.104 + PUSH_SLOT_ATTR, PUSH_GLYPH_ATTR_OBS,
1.105 + PUSH_GLYPH_METRIC, PUSH_FEAT,
1.106 + PUSH_ATT_TO_GATTR_OBS, PUSH_ATT_TO_GLYPH_METRIC,
1.107 + PUSH_ISLOT_ATTR,
1.108 +
1.109 + PUSH_IGLYPH_ATTR, // not implemented
1.110 +
1.111 + POP_RET, RET_ZERO, RET_TRUE,
1.112 + IATTR_SET, IATTR_ADD, IATTR_SUB,
1.113 + PUSH_PROC_STATE, PUSH_VERSION,
1.114 + PUT_SUBS, PUT_SUBS2, PUT_SUBS3,
1.115 + PUT_GLYPH, PUSH_GLYPH_ATTR, PUSH_ATT_TO_GLYPH_ATTR,
1.116 + MAX_OPCODE,
1.117 + // private opcodes for internal use only, comes after all other on disk opcodes
1.118 + TEMP_COPY = MAX_OPCODE
1.119 +};
1.120 +
1.121 +struct opcode_t
1.122 +{
1.123 + instr impl[2];
1.124 + uint8 param_sz;
1.125 + char name[MAX_NAME_LEN];
1.126 +};
1.127 +
1.128 +
1.129 +class Machine
1.130 +{
1.131 +public:
1.132 + typedef int32 stack_t;
1.133 + static size_t const STACK_ORDER = 10,
1.134 + STACK_MAX = 1 << STACK_ORDER,
1.135 + STACK_GUARD = 2;
1.136 +
1.137 + class Code;
1.138 +
1.139 + enum status_t {
1.140 + finished = 0,
1.141 + stack_underflow,
1.142 + stack_not_empty,
1.143 + stack_overflow,
1.144 + slot_offset_out_bounds
1.145 + };
1.146 +
1.147 + Machine(SlotMap &) throw();
1.148 + static const opcode_t * getOpcodeTable() throw();
1.149 +
1.150 + CLASS_NEW_DELETE;
1.151 +
1.152 + SlotMap & slotMap() const throw();
1.153 + status_t status() const throw();
1.154 + operator bool () const throw();
1.155 +
1.156 +private:
1.157 + void check_final_stack(const stack_t * const sp);
1.158 + stack_t run(const instr * program, const byte * data,
1.159 + slotref * & map) HOT;
1.160 +
1.161 + SlotMap & _map;
1.162 + stack_t _stack[STACK_MAX + 2*STACK_GUARD];
1.163 + status_t _status;
1.164 +};
1.165 +
1.166 +inline Machine::Machine(SlotMap & map) throw()
1.167 +: _map(map), _status(finished)
1.168 +{
1.169 + // Initialise stack guard +1 entries as the stack pointer points to the
1.170 + // current top of stack, hence the first push will never write entry 0.
1.171 + // Initialising the guard space like this is unnecessary and is only
1.172 + // done to keep valgrind happy during fuzz testing. Hopefully loop
1.173 + // unrolling will flatten this.
1.174 + for (size_t n = STACK_GUARD + 1; n; --n) _stack[n-1] = 0;
1.175 +}
1.176 +
1.177 +inline SlotMap& Machine::slotMap() const throw()
1.178 +{
1.179 + return _map;
1.180 +}
1.181 +
1.182 +inline Machine::status_t Machine::status() const throw()
1.183 +{
1.184 + return _status;
1.185 +}
1.186 +
1.187 +inline void Machine::check_final_stack(const int32 * const sp)
1.188 +{
1.189 + stack_t const * const base = _stack + STACK_GUARD,
1.190 + * const limit = base + STACK_MAX;
1.191 + if (sp < base) _status = stack_underflow; // This should be impossible now.
1.192 + else if (sp >= limit) _status = stack_overflow; // So should this.
1.193 + else if (sp != base) _status = stack_not_empty;
1.194 +}
1.195 +
1.196 +} // namespace vm
1.197 +} // namespace graphite2
1.198 +
1.199 +
1.200 +
