/***************************************************************************
drccache.c
Universal dynamic recompiler cache management.
****************************************************************************
Copyright Aaron Giles
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
* Neither the name 'MAME' nor the names of its contributors may be
used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY AARON GILES ''AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL AARON GILES BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
***************************************************************************/
#include "emu.h"
#include "drccache.h"
//**************************************************************************
// MACROS
//**************************************************************************
// ensure that all memory allocated is aligned to an 8-byte boundary
#define ALIGN_PTR_UP(p) ((void *)(((FPTR)(p) + (CACHE_ALIGNMENT - 1)) & ~(CACHE_ALIGNMENT - 1)))
#define ALIGN_PTR_DOWN(p) ((void *)((FPTR)(p) & ~(CACHE_ALIGNMENT - 1)))
//**************************************************************************
// DRC CACHE
//**************************************************************************
//-------------------------------------------------
// drc_cache - constructor
//-------------------------------------------------
drc_cache::drc_cache(size_t bytes)
: m_near((drccodeptr)osd_alloc_executable(bytes)),
m_neartop(m_near),
m_base(m_near + NEAR_CACHE_SIZE),
m_top(m_base),
m_end(m_near + bytes),
m_codegen(0),
m_size(bytes)
{
memset(m_free, 0, sizeof(m_free));
memset(m_nearfree, 0, sizeof(m_nearfree));
}
//-------------------------------------------------
// ~drc_cache - destructor
//-------------------------------------------------
drc_cache::~drc_cache()
{
// release the memory
osd_free_executable(m_near, m_size);
}
//-------------------------------------------------
// flush - flush the cache contents
//-------------------------------------------------
void drc_cache::flush()
{
// can't flush in the middle of codegen
assert(m_codegen == NULL);
// just reset the top back to the base and re-seed
m_top = m_base;
}
//-------------------------------------------------
// alloc - allocate permanent memory from the
// cache
//-------------------------------------------------
void *drc_cache::alloc(size_t bytes)
{
assert(bytes > 0);
// pick first from the free list
if (bytes < MAX_PERMANENT_ALLOC)
{
free_link **linkptr = &m_free[(bytes + CACHE_ALIGNMENT - 1) / CACHE_ALIGNMENT];
free_link *link = *linkptr;
if (link != NULL)
{
*linkptr = link->m_next;
return link;
}
}
// if no space, we just fail
drccodeptr ptr = (drccodeptr)ALIGN_PTR_DOWN(m_end - bytes);
if (m_top > ptr)
return NULL;
// otherwise update the end of the cache
m_end = ptr;
return ptr;
}
//-------------------------------------------------
// alloc_near - allocate permanent memory from
// the near part of the cache
//-------------------------------------------------
void *drc_cache::alloc_near(size_t bytes)
{
assert(bytes > 0);
// pick first from the free list
if (bytes < MAX_PERMANENT_ALLOC)
{
free_link **linkptr = &m_nearfree[(bytes + CACHE_ALIGNMENT - 1) / CACHE_ALIGNMENT];
free_link *link = *linkptr;
if (link != NULL)
{
*linkptr = link->m_next;
return link;
}
}
// if no space, we just fail
drccodeptr ptr = (drccodeptr)ALIGN_PTR_UP(m_neartop);
if (ptr + bytes > m_base)
return NULL;
// otherwise update the top of the near part of the cache
m_neartop = ptr + bytes;
return ptr;
}
//-------------------------------------------------
// alloc_temporary - allocate temporary memory
// from the cache
//-------------------------------------------------
void *drc_cache::alloc_temporary(size_t bytes)
{
// can't allocate in the middle of codegen
assert(m_codegen == NULL);
// if no space, we just fail
drccodeptr ptr = m_top;
if (ptr + bytes >= m_end)
return NULL;
// otherwise, update the cache top
m_top = (drccodeptr)ALIGN_PTR_UP(ptr + bytes);
return ptr;
}
//-------------------------------------------------
// free - release permanent memory allocated from
// the cache
//-------------------------------------------------
void drc_cache::dealloc(void *memory, size_t bytes)
{
assert(bytes < MAX_PERMANENT_ALLOC);
assert(((drccodeptr)memory >= m_near && (drccodeptr)memory < m_base) || ((drccodeptr)memory >= m_end && (drccodeptr)memory < m_near + m_size));
// determine which free list to add to
free_link **linkptr;
if ((drccodeptr)memory < m_base)
linkptr = &m_nearfree[(bytes + CACHE_ALIGNMENT - 1) / CACHE_ALIGNMENT];
else
linkptr = &m_free[(bytes + CACHE_ALIGNMENT - 1) / CACHE_ALIGNMENT];
// link is into the free list for our size
free_link *link = (free_link *)memory;
link->m_next = *linkptr;
*linkptr = link;
}
//-------------------------------------------------
// begin_codegen - begin code generation
//-------------------------------------------------
drccodeptr *drc_cache::begin_codegen(UINT32 reserve_bytes)
{
// can't restart in the middle of codegen
assert(m_codegen == NULL);
assert(m_ooblist.first() == NULL);
// if still no space, we just fail
drccodeptr ptr = m_top;
if (ptr + reserve_bytes >= m_end)
return NULL;
// otherwise, return a pointer to the cache top
m_codegen = m_top;
return &m_top;
}
//-------------------------------------------------
// end_codegen - complete code generation
//-------------------------------------------------
drccodeptr drc_cache::end_codegen()
{
drccodeptr result = m_codegen;
// run the OOB handlers
oob_handler *oob;
while ((oob = m_ooblist.detach_head()) != NULL)
{
// call the callback
oob->m_callback(&m_top, oob->m_param1, oob->m_param2);
assert(m_top - m_codegen < CODEGEN_MAX_BYTES);
// release our memory
dealloc(oob, sizeof(*oob));
}
// update the cache top
m_top = (drccodeptr)ALIGN_PTR_UP(m_top);
m_codegen = NULL;
return result;
}
//-------------------------------------------------
// request_oob_codegen - request callback for
// out-of-band codegen
//-------------------------------------------------
void drc_cache::request_oob_codegen(drc_oob_delegate callback, void *param1, void *param2)
{
assert(m_codegen != NULL);
// pull an item from the free list
oob_handler *oob = (oob_handler *)alloc(sizeof(*oob));
assert(oob != NULL);
// fill it in
oob->m_callback = callback;
oob->m_param1 = param1;
oob->m_param2 = param2;
// add to the tail
m_ooblist.append(*oob);
}