/**********************************************************************
* polocal.c
* P-Code Local Optimizer
*
* Copyright (C) 2008 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name NuttX 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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 THE
* COPYRIGHT OWNER OR CONTRIBUTORS 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.
*
**********************************************************************/
/**********************************************************************
* Included Files
**********************************************************************/
#include <stdio.h>
#include "keywords.h"
#include "podefs.h"
#include "pinsn32.h"
#include "pofflib.h"
#include "paslib.h"
#include "pinsn.h"
#include "pcopt.h"
#include "plopt.h"
#include "pjopt.h"
#include "polocal.h"
/**********************************************************************
* Private Function Prototypes
**********************************************************************/
static void initPTable (void);
static void putPCodeFromTable (void);
static void setupPointer (void);
/**********************************************************************
* Global Variables
**********************************************************************/
OPTYPE ptable [WINDOW]; /* Pcode Table */
OPTYPE *pptr [WINDOW]; /* Valid Pcode Pointers */
int nops = 0; /* No. Valid Pcode Pointers */
int end_out = 0; /* 1 = oEND pcode has been output */
/**********************************************************************
* Private Variables
**********************************************************************/
static poffHandle_t myPoffHandle; /* Handle to POFF object */
static poffProgHandle_t myPoffProgHandle;/* Handle to temporary POFF object */
/**********************************************************************
* Global Functions
**********************************************************************/
/***********************************************************************/
void localOptimization(poffHandle_t poffHandle,
poffProgHandle_t poffProgHandle)
{
int nchanges;
TRACE(stderr, "[pass2]");
/* Save the handles for use by other, private functions */
myPoffHandle = poffHandle;
myPoffProgHandle = poffProgHandle;
/* Initialization */
initPTable();
/* Outer loop traverse the file op-code by op-code until the oEND P-Code
* has been output. NOTE: it is assumed throughout that oEND is the
* final P-Code in the program data section.
*/
while (!(end_out))
{
/* The inner loop optimizes the buffered P-Codes until no further
* changes can be made. Then the outer loop will advance the buffer
* by one P-Code
*/
do
{
nchanges = unaryOptimize ();
nchanges += binaryOptimize();
nchanges += BranchOptimize();
nchanges += LoadOptimize();
nchanges += StoreOptimize();
} while (nchanges);
putPCodeFromTable();
}
}
/***********************************************************************/
void deletePcode(int delIndex)
{
TRACE(stderr, "[deletePcode]");
PUTOP(pptr[delIndex], oNOP);
PUTARG(pptr[delIndex], 0);
setupPointer();
}
/**********************************************************************/
void deletePcodePair(int delIndex1, int delIndex2)
{
TRACE(stderr, "[deletePcodePair]");
PUTOP(pptr[delIndex1], oNOP);
PUTARG(pptr[delIndex1], 0);
PUTOP(pptr[delIndex2], oNOP);
PUTARG(pptr[delIndex2], 0);
setupPointer();
}
/**********************************************************************
* Private Functions
**********************************************************************/
/***********************************************************************/
static void putPCodeFromTable(void)
{
register int i;
TRACE(stderr, "[putPCodeFromTable]");
/* Transfer all buffered P-Codes (except NOPs) to the optimized file */
do
{
if ((GETOP(&ptable[0]) != oNOP) && !(end_out))
{
insn_AddTmpOpCode(myPoffProgHandle, &ptable[0]);
end_out = (GETOP(&ptable[0]) == oEND);
}
/* Move all P-Codes down one slot */
for (i = 1; i < WINDOW; i++)
{
ptable[i-1] = ptable[i];
}
/* Then fill the end slot with a new P-Code from the input file */
insn_GetOpCode(myPoffHandle, &ptable[WINDOW-1]);
} while (GETOP(&ptable[0]) == oNOP);
setupPointer();
}
/**********************************************************************/
static void setupPointer(void)
{
register int pindex;
TRACE(stderr, "[setupPointer]");
for (pindex = 0; pindex < WINDOW; pindex++)
pptr[pindex] = (OPTYPE *) NULL;
nops = 0;
for (pindex = 0; pindex < WINDOW; pindex++)
{
switch (GETOP(&ptable[pindex]))
{
/* Terminate list when a break from sequential logic is
* encountered
*/
case oRET :
case oEND :
case oJMP :
case oLABEL :
case oPCAL :
return;
/* Terminate list when a condition break from sequential logic is
* encountered but include the conditional branch in the list
*/
case oJEQUZ :
case oJNEQZ :
case oJLTZ :
case oJGTEZ :
case oJGTZ :
case oJLTEZ :
pptr[nops] = &ptable[pindex];
nops++;
return;
/* Skip over NOPs and comment class pcodes */
case oNOP :
case oLINE :
break;
/* Include all other pcodes in the optimization list and continue */
default :
pptr[nops] = &ptable[pindex];
nops++;
}
}
}
/**********************************************************************/
static void initPTable(void)
{
register int i;
TRACE(stderr, "[intPTable]");
/* Skip over leading pcodes. NOTE: assumes executable begins after
* the first oLABEL pcode
*/
do
{
insn_GetOpCode(myPoffHandle, &ptable[0]);
insn_AddTmpOpCode(myPoffProgHandle, &ptable[0]);
}
while ((GETOP(&ptable[0]) != oLABEL) && (GETOP(&ptable[0]) != oEND));
/* Fill the pcode window and setup pointers to working section */
for (i = 0; i < WINDOW; i++)
{
insn_GetOpCode(myPoffHandle, &ptable[i]);
}
setupPointer();
}
/***********************************************************************/
