px4-firmware/misc/pascal/insn32/popt/pcopt.c

841 lines
26 KiB
C

/**********************************************************************
* pcopt.c
* Constant Expression Optimizations
*
* Copyright (C) 2008-2009 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 <stdint.h>
#include <stdio.h>
#include "keywords.h"
#include "pdefs.h"
#include "pinsn32.h"
#include "paslib.h"
#include "popt.h"
#include "polocal.h"
#include "pcopt.h"
/**********************************************************************/
int unaryOptimize(void)
{
register uint32_t temp;
register int i;
int nchanges = 0;
TRACE(stderr, "[unaryOptimize]");
/* At least two pcodes are need to perform unary optimizations */
i = 0;
while (i < nops-1)
{
/* Check for a constant value being pushed onto the stack */
if (GETOP(pptr[i]) == oPUSH)
{
switch (GETOP(pptr[i+1]))
{
/* Delete unary operators on constants */
case oNEG :
PUTARG(pptr[i], -GETARG(pptr[i]));
deletePcode(i+1);
nchanges++;
break;
case oABS :
if ((int32_t)GETARG(pptr[i]) < 0)
PUTARG(pptr[i], -(int32_t)GETARG(pptr[i]));
deletePcode(i+1);
nchanges++;
break;
case oINC :
PUTARG(pptr[i], GETARG(pptr[i]) + 1);
deletePcode(i+1);
nchanges++;
break;
case oDEC :
PUTARG(pptr[i], GETARG(pptr[i]) - 1);
deletePcode(i+1);
nchanges++;
break;
case oNOT :
PUTARG(pptr[i], ~GETARG(pptr[i]));
PUTARG(pptr[i], ~(GETARG(pptr[i])));
deletePcode(i+1);
nchanges++;
break;
/* Simplify binary operations on constants */
case oADD :
if (GETARG(pptr[i]) == 0)
{
deletePcodePair(i, (i+1));
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i+1], oINC);
deletePcode(i);
nchanges++;
} /* end else if */
else if (GETARG(pptr[i]) == ARGONES)
{
PUTOP(pptr[i+1], oDEC);
deletePcode(i);
nchanges++;
} /* end else if */
else i++;
break;
case oSUB :
if (GETARG(pptr[i]) == 0)
{
deletePcodePair(i, (i+1));
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i+1], oDEC);
deletePcode(i);
nchanges++;
} /* end else if */
else if (GETARG(pptr[i]) == ARGONES)
{
PUTOP(pptr[i+1], oINC);
deletePcode(i);
nchanges++;
} /* end else if */
else i++;
break;
case oMUL :
case oDIV :
temp = 0;
switch (GETARG(pptr[i]))
{
case 1 :
deletePcodePair(i, (i+1));
nchanges++;
break;
case 16384 : temp++;
case 8192 : temp++;
case 4096 : temp++;
case 2048 : temp++;
case 1024 : temp++;
case 512 : temp++;
case 256 : temp++;
case 128 : temp++;
case 64 : temp++;
case 32 : temp++;
case 16 : temp++;
case 8 : temp++;
case 4 : temp++;
case 2 : temp++;
PUTARG(pptr[i], temp);
if (GETOP(pptr[i+1]) == oMUL)
PUTOP(pptr[i+1], oSLL);
else
PUTOP(pptr[i+1], oSRA);
nchanges++;
i++;
break;
default :
i++;
break;
} /* end switch */
break;
case oSLL :
case oSRL :
case oSRA :
case oOR :
if (GETARG(pptr[i]) == 0)
{
deletePcodePair(i, (i+1));
nchanges++;
} /* end if */
else i++;
break;
case oAND :
if (GETARG(pptr[i]) == ARGONES)
{
deletePcodePair(i, (i+1));
nchanges++;
} /* end if */
else i++;
break;
/* Delete comparisons of constants to zero */
case oEQUZ :
if (GETARG(pptr[i]) == 0)
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcode(i+1);
nchanges++;
break;
case oNEQZ :
if (GETARG(pptr[i]) != 0)
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcode(i+1);
nchanges++;
break;
case oLTZ :
if ((int32_t)GETARG(pptr[i]) < 0)
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcode(i+1);
nchanges++;
break;
case oGTEZ :
if ((int32_t)GETARG(pptr[i]) >= 0)
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcode(i+1);
nchanges++;
break;
case oGTZ :
if (GETARG(pptr[i]) > 0)
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcode(i+1);
nchanges++;
break;
case oLTEZ :
if (GETARG(pptr[i]) <= 0)
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcode(i+1);
nchanges++;
break;
/* Simplify comparisons with certain constants */
case oEQU :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1],oEQUZ);
deletePcode(i);
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i], oDEC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oEQUZ);
nchanges++;
} /* end else if */
else if ((int32_t)GETARG(pptr[i]) == -1)
{
PUTOP(pptr[i], oINC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oEQUZ);
nchanges++;
} /* end else if */
else i++;
break;
case oNEQ :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1], oNEQZ);
deletePcode(i);
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i], oDEC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oNEQZ);
nchanges++;
} /* end else if */
else if ((int32_t)GETARG(pptr[i]) == -1)
{
PUTOP(pptr[i], oINC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oNEQZ);
nchanges++;
} /* end else if */
else i++;
break;
case oLT :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1], oLTZ);
deletePcode(i);
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i], oDEC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oLTZ);
nchanges++;
} /* end else if */
else if ((int32_t)GETARG(pptr[i]) == -1)
{
PUTOP(pptr[i], oINC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oLTZ);
nchanges++;
} /* end else if */
else i++;
break;
case oGTE :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1], oGTEZ);
deletePcode(i);
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i], oDEC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oGTEZ);
nchanges++;
} /* end else if */
else if ((int32_t)GETARG(pptr[i]) == -1)
{
PUTOP(pptr[i], oINC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oGTEZ);
nchanges++;
} /* end else if */
else i++;
break;
case oGT :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1], oGTZ);
deletePcode(i);
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i], oDEC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oGTZ);
nchanges++;
} /* end else if */
else if ((int32_t)GETARG(pptr[i]) == -1)
{
PUTOP(pptr[i], oINC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oGTZ);
nchanges++;
} /* end else if */
else i++;
break;
case oLTE :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1], oLTEZ);
deletePcode(i);
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i], oDEC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oLTEZ);
nchanges++;
} /* end else if */
else if ((int32_t)GETARG(pptr[i]) == -1)
{
PUTOP(pptr[i], oINC);
PUTARG(pptr[i], 0);
PUTOP(pptr[i+1], oLTEZ);
nchanges++;
} /* end else if */
else i++;
break;
/* Simplify or delete condition branches on constants */
case oJEQUZ :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+1], oJMP);
deletePcode(i);
} /* end if */
else
deletePcodePair(i, (i+1));
nchanges++;
break;
case oJNEQZ :
if (GETARG(pptr[i]) != 0)
{
PUTOP(pptr[i+1], oJMP);
deletePcode(i);
} /* end if */
else
deletePcodePair(i, (i+1));
nchanges++;
break;
case oJLTZ :
if ((int32_t)GETARG(pptr[i]) < 0)
{
PUTOP(pptr[i+1], oJMP);
deletePcode(i);
} /* end if */
else
deletePcodePair(i, (i+1));
nchanges++;
break;
case oJGTEZ :
if ((int32_t)GETARG(pptr[i]) >= 0)
{
PUTOP(pptr[i+1], oJMP);
deletePcode(i);
} /* end if */
else
deletePcodePair(i, (i+1));
nchanges++;
break;
case oJGTZ :
if (GETARG(pptr[i]) > 0)
{
PUTOP(pptr[i+1], oJMP);
deletePcode(i);
} /* end if */
else
deletePcodePair(i, (i+1));
nchanges++;
break;
case oJLTEZ :
if (GETARG(pptr[i]) <= 0)
{
PUTOP(pptr[i+1], oJMP);
deletePcode(i);
} /* end if */
else
deletePcodePair(i, (i+1));
nchanges++;
break;
default :
i++;
break;
} /* end switch */
} /* end if */
/* Delete multiple modifications of DSEG pointer */
else if (GETOP(pptr[i]) == oINDS)
{
if (GETOP(pptr[i+1]) == oINDS)
{
PUTARG(pptr[i], GETARG(pptr[i] + GETARG(pptr[i+1])));
deletePcode(i+1);
} /* end if */
else i++;
} /* end else if */
else i++;
} /* end while */
return (nchanges);
} /* end unaryOptimize */
/**********************************************************************/
int binaryOptimize(void)
{
register int i;
int nchanges = 0;
TRACE(stderr, "[binaryOptimize]");
/* At least two pcodes are needed to perform the following binary */
/* operator optimizations */
i = 0;
while (i < nops-2)
{
if (GETOP(pptr[i]) == oPUSH)
{
if (GETOP(pptr[i+1]) == oPUSH)
{
switch (GETOP(pptr[i+2]))
{
case oADD :
PUTARG(pptr[i], GETARG(pptr[i]) + GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oSUB :
PUTARG(pptr[i], GETARG(pptr[i]) - GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oMUL :
PUTARG(pptr[i], GETARG(pptr[i]) * GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oDIV :
PUTARG(pptr[i], GETARG(pptr[i]) / (int32_t)GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oMOD :
PUTARG(pptr[i], GETARG(pptr[i]) % GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oSLL :
PUTARG(pptr[i], GETARG(pptr[i]) << GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oSRL :
PUTARG(pptr[i], GETARG(pptr[i]) >> GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oSRA :
PUTARG(pptr[i], (int32_t)GETARG(pptr[i]) >> GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oOR :
PUTARG(pptr[i], GETARG(pptr[i]) | GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oAND :
PUTARG(pptr[i], GETARG(pptr[i]) & GETARG(pptr[i+1]));
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oEQU :
if (GETARG(pptr[i]) == GETARG(pptr[i+1]))
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oNEQ :
if (GETARG(pptr[i]) != GETARG(pptr[i+1]))
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oLT :
if ((int32_t)GETARG(pptr[i]) < (int32_t)GETARG(pptr[i+1]))
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oGTE :
if ((int32_t)GETARG(pptr[i]) >= (int32_t)GETARG(pptr[i+1]))
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oGT :
if ((int32_t)GETARG(pptr[i]) > (int32_t)GETARG(pptr[i+1]))
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcodePair((i+1), (i+2));
nchanges++;
break;
case oLTE :
if ((int32_t)GETARG(pptr[i]) <= (int32_t)GETARG(pptr[i+1]))
PUTARG(pptr[i], -1);
else
PUTARG(pptr[i], 0);
deletePcodePair((i+1), (i+2));
nchanges++;
break;
default :
i++;
break;
} /* end switch */
} /* end if */
/* A single (constant) pcode is sufficient to perform the */
/* following binary operator optimizations */
else if ((GETOP(pptr[i+1]) == oLDSH) || (GETOP(pptr[i+1]) == oLDSB) ||
(GETOP(pptr[i+1]) == oLAS) || (GETOP(pptr[i+1]) == oLAC))
{
switch (GETOP(pptr[i+2]))
{
case oADD :
if (GETARG(pptr[i]) == 0)
{
deletePcodePair(i, (i+2));
nchanges++;
} /* end if */
else if (GETARG(pptr[i]) == 1)
{
PUTOP(pptr[i+2], oINC);
deletePcode(i);
nchanges++;
} /* end else if */
else if (GETARG(pptr[i]) == ARGONES)
{
PUTOP(pptr[i+2], oDEC);
deletePcode(i);
nchanges++;
} /* end else if */
else i++;
break;
case oSUB :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i], oNEG);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
case oMUL :
{
int32_t stmp32 = 0;
switch (GETARG(pptr[i]))
{
case 1 :
deletePcodePair(i, (i+2));
nchanges++;
break;
case 16384 : stmp32++;
case 8192 : stmp32++;
case 4096 : stmp32++;
case 2048 : stmp32++;
case 1024 : stmp32++;
case 512 : stmp32++;
case 256 : stmp32++;
case 128 : stmp32++;
case 64 : stmp32++;
case 32 : stmp32++;
case 16 : stmp32++;
case 8 : stmp32++;
case 4 : stmp32++;
case 2 : stmp32++;
PUTOP(pptr[i], GETOP(pptr[i+1]));
PUTARG(pptr[i], GETARG(pptr[i+1]));
PUTOP(pptr[i+1], oPUSH);
PUTARG(pptr[i+1], stmp32);
PUTOP(pptr[i+2], oSLL);
nchanges++;
i++;
break;
default :
i++;
break;
}
}
break;
case oOR :
if (GETARG(pptr[i]) == 0)
{
deletePcodePair(i, (i+2));
nchanges++;
} /* end if */
else i++;
break;
case oAND :
if (GETARG(pptr[i]) == ARGONES)
{
deletePcodePair(i, (i+2));
nchanges++;
} /* end if */
else i++;
break;
case oEQU :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+2], oEQUZ);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
case oNEQ :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+2], oNEQZ);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
case oLT :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+2], oGTEZ);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
case oGTE :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+2], oLTZ);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
case oGT :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+2], oLTEZ);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
case oLTE :
if (GETARG(pptr[i]) == 0)
{
PUTOP(pptr[i+2], oGTZ);
deletePcode(i);
nchanges++;
} /* end if */
else i++;
break;
default :
i++;
break;
} /* end switch */
} /* end else if */
else i++;
} /* end if */
/* Misc improvements on binary operators */
else if (GETOP(pptr[i]) == oNEG)
{
/* Negation followed by add is subtraction */
if (GETOP(pptr[i+1]) == oADD)
{
PUTOP(pptr[i+1], oSUB);
deletePcode(i);
nchanges++;
}
/* Negation followed by subtraction is addition */
else if (GETOP(pptr[i]) == oSUB)
{
PUTOP(pptr[i+1], oADD);
deletePcode(i);
nchanges++;
}
else i++;
}
else i++;
} /* end while */
return (nchanges);
} /* end binaryOptimize */
/**********************************************************************/