ack/util/ego/cs/cs.c
George Koehler 9037d137f5 Add prototypes, void in util/ego/share
This uncovers a problem in il/il_aux.c: it passes 3 arguments to
getlines(), but the function expects 4 arguments.  I add FALSE as the
4th argument.  TRUE would fill in the list of mesregs.  IL uses
mesregs during phase 1, but this call to getlines() is in phase 2.
TRUE would leak memory unless I added a call to Ldeleteset(mesregs).
So I pass FALSE.

Functions passed to go() now have a `void *` parameter because
no_action() now takes a `void *`.
2017-11-15 17:19:56 -05:00

86 lines
2 KiB
C

/* $Id$ */
/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/* C O M M O N S U B E X P R E S S I O N E L I M I N A T I O N */
#include <stdlib.h>
#include <stdio.h>
#include "../share/types.h"
#include "../share/lset.h"
#include "../share/debug.h"
#include "../share/go.h"
#include "cs.h"
#include "cs_aux.h"
#include "cs_avail.h"
#include "cs_debug.h"
#include "cs_elim.h"
#include "cs_entity.h"
#include "cs_profit.h"
#include "cs_stack.h"
#include "cs_vnm.h"
int Scs; /* Number of optimizations found. */
STATIC cs_clear()
{
clr_avails();
clr_entities();
clr_stack();
start_valnum();
}
STATIC void cs_optimize(void *vp)
{
/* Optimize all basic blocks of one procedure. */
proc_p p = vp;
register bblock_p rbp, bdone;
if (IS_ENTERED_WITH_GTO(p)) return;
avails = (avail_p) 0;
entities = Lempty_set();
cs_clear();
rbp = p->p_start;
while (rbp != (bblock_p) 0) {
/* First we build a list of common expressions with the
* value numbering algorithm. We take blocks in textual order
* as long as the next block can only be reached through the
* block we have just done. Note that if a block is preceded
* by itself, the number of predecessors is greater than 1,
* but the previous block can still be its immediate dominator.
*/
do { vnm(rbp); bdone = rbp;
OUTTRACE("basic block %d processed", bdone->b_id);
rbp = rbp->b_next;
} while (rbp != (bblock_p) 0 && rbp->b_idom == bdone &&
Lnrelems(rbp->b_pred) == 1
);
OUTTRACE("value numbering completed", 0);
OUTAVAILS(); OUTENTITIES();
/* Now we put out the instructions without common
* subexpressions but with the use of temporaries,
* which will be local variables of procedure p.
*/
eliminate(p);
cs_clear();
}
}
main(argc, argv)
int argc;
char *argv[];
{
Scs = 0;
go(argc, argv, no_action, cs_optimize, cs_machinit, no_action);
report("Duplicate expressions eliminated", Scs);
exit(0);
}