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| -rw-r--r-- | gfx/graphite2/src/inc/Machine.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/gfx/graphite2/src/inc/Machine.h b/gfx/graphite2/src/inc/Machine.h new file mode 100644 index 0000000000..b23819fb98 --- /dev/null +++ b/gfx/graphite2/src/inc/Machine.h @@ -0,0 +1,207 @@ +/* GRAPHITE2 LICENSING + + Copyright 2010, SIL International + All rights reserved. + + This library is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2.1 of 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 + Lesser General Public License for more details. + + You should also have received a copy of the GNU Lesser General Public + License along with this library in the file named "LICENSE". + If not, write to the Free Software Foundation, 51 Franklin Street, + Suite 500, Boston, MA 02110-1335, USA or visit their web page on the + internet at http://www.fsf.org/licenses/lgpl.html. + +Alternatively, the contents of this file may be used under the terms of the +Mozilla Public License (http://mozilla.org/MPL) or 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 general interpreter interface. +// Author: Tim Eves + +// Build one of direct_machine.cpp or call_machine.cpp to implement this +// interface. + +#pragma once +#include <cstring> +#include <limits> +#include <graphite2/Types.h> +#include "inc/Main.h" + +#if defined(__GNUC__) +#if defined(__clang__) || (__GNUC__ * 100 + __GNUC_MINOR__ * 10) < 430 +#define HOT +#if defined(__x86_64) +#define REGPARM(n) __attribute__((regparm(n))) +#else +#define REGPARM(n) +#endif +#else +#define HOT __attribute__((hot)) +#if defined(__x86_64) +#define REGPARM(n) __attribute__((hot, regparm(n))) +#else +#define REGPARM(n) +#endif +#endif +#else +#define HOT +#define REGPARM(n) +#endif + +#if defined(__MINGW32__) +// MinGW's <limits> at some point includes winnt.h which #define's a +// DELETE macro, which conflicts with enum opcode below, so we undefine +// it here. +#undef DELETE +#endif + +namespace graphite2 { + +// Forward declarations +class Segment; +class Slot; +class SlotMap; + + +namespace vm +{ + + +typedef void * instr; +typedef Slot * slotref; + +enum {VARARGS = 0xff, MAX_NAME_LEN=32}; + +enum opcode { + NOP = 0, + + PUSH_BYTE, PUSH_BYTEU, PUSH_SHORT, PUSH_SHORTU, PUSH_LONG, + + ADD, SUB, MUL, DIV, + MIN_, MAX_, + NEG, + TRUNC8, TRUNC16, + + COND, + + AND, OR, NOT, + EQUAL, NOT_EQ, + LESS, GTR, LESS_EQ, GTR_EQ, + + NEXT, NEXT_N, COPY_NEXT, + PUT_GLYPH_8BIT_OBS, PUT_SUBS_8BIT_OBS, PUT_COPY, + INSERT, DELETE, + ASSOC, + CNTXT_ITEM, + + ATTR_SET, ATTR_ADD, ATTR_SUB, + ATTR_SET_SLOT, + IATTR_SET_SLOT, + PUSH_SLOT_ATTR, PUSH_GLYPH_ATTR_OBS, + PUSH_GLYPH_METRIC, PUSH_FEAT, + PUSH_ATT_TO_GATTR_OBS, PUSH_ATT_TO_GLYPH_METRIC, + PUSH_ISLOT_ATTR, + + PUSH_IGLYPH_ATTR, // not implemented + + POP_RET, RET_ZERO, RET_TRUE, + IATTR_SET, IATTR_ADD, IATTR_SUB, + PUSH_PROC_STATE, PUSH_VERSION, + PUT_SUBS, PUT_SUBS2, PUT_SUBS3, + PUT_GLYPH, PUSH_GLYPH_ATTR, PUSH_ATT_TO_GLYPH_ATTR, + BITOR, BITAND, BITNOT, + BITSET, SET_FEAT, + MAX_OPCODE, + // private opcodes for internal use only, comes after all other on disk opcodes + TEMP_COPY = MAX_OPCODE +}; + +struct opcode_t +{ + instr impl[2]; + uint8 param_sz; + char name[MAX_NAME_LEN]; +}; + + +class Machine +{ +public: + typedef int32 stack_t; + static size_t const STACK_ORDER = 10, + STACK_MAX = 1 << STACK_ORDER, + STACK_GUARD = 2; + + class Code; + + enum status_t { + finished = 0, + stack_underflow, + stack_not_empty, + stack_overflow, + slot_offset_out_bounds, + died_early + }; + + Machine(SlotMap &) throw(); + static const opcode_t * getOpcodeTable() throw(); + + CLASS_NEW_DELETE; + + SlotMap & slotMap() const throw(); + status_t status() const throw(); +// operator bool () const throw(); + +private: + void check_final_stack(const stack_t * const sp); + stack_t run(const instr * program, const byte * data, + slotref * & map) HOT; + + SlotMap & _map; + stack_t _stack[STACK_MAX + 2*STACK_GUARD]; + status_t _status; +}; + +inline Machine::Machine(SlotMap & map) throw() +: _map(map), _status(finished) +{ + // Initialise stack guard +1 entries as the stack pointer points to the + // current top of stack, hence the first push will never write entry 0. + // Initialising the guard space like this is unnecessary and is only + // done to keep valgrind happy during fuzz testing. Hopefully loop + // unrolling will flatten this. + for (size_t n = STACK_GUARD + 1; n; --n) _stack[n-1] = 0; +} + +inline SlotMap& Machine::slotMap() const throw() +{ + return _map; +} + +inline Machine::status_t Machine::status() const throw() +{ + return _status; +} + +inline void Machine::check_final_stack(const stack_t * const sp) +{ + if (_status != finished) return; + + stack_t const * const base = _stack + STACK_GUARD, + * const limit = base + STACK_MAX; + if (sp < base) _status = stack_underflow; // This should be impossible now. + else if (sp >= limit) _status = stack_overflow; // So should this. + else if (sp != base) _status = stack_not_empty; +} + +} // namespace vm +} // namespace graphite2 |