Added code to optimize multiplies with constants

diff --git a/util/opt/ext.h b/util/opt/ext.h
index 5eba32a..a389eb4 100644 (file)
--- a/util/opt/ext.h
+++ b/util/opt/ext.h
@@ -11,6 +11,8 @@ extern        unsigned linecount;
 extern int     prodepth;
 extern bool    Lflag;
 extern bool    nflag;
+extern int     repl_muls;
+extern bool    repl_longmuls;
 extern byte    em_flag[];
 extern line_p  instrs,pseudos;
 extern FILE    *outfile;

diff --git a/util/opt/main.c b/util/opt/main.c
index 33b0ea8..74d42b5 100644 (file)
--- a/util/opt/main.c
+++ b/util/opt/main.c
@@ -28,7 +28,7 @@ main(argc,argv) int argc; char *argv[]; {
        while (argc-->1 && **++argv == '-')
                flags(*argv);
        if (argc>1) {
-               fprintf(stderr,"Usage: %s [-Ln] [name]\n",progname);
+               fprintf(stderr,"Usage: %s [-Ln] [-m<num>] [name]\n",progname);
                exit(-1);
        }
        if (argc)
@@ -47,6 +47,11 @@ flags(s) register char *s; {
                switch(*s) {
                case 'L':       Lflag = TRUE; break;
                case 'n':       nflag = TRUE; break;
+               case 'm':       if (*(s+1) == 'l') {
+                                       s++;
+                                       repl_longmuls = TRUE;
+                               }
+                               repl_muls = atoi(s+1); break;
                }
 }
 

diff --git a/util/opt/peephole.c b/util/opt/peephole.c
index 2f117d5..3df8041 100644 (file)
--- a/util/opt/peephole.c
+++ b/util/opt/peephole.c
@@ -608,7 +608,30 @@ basicblock(alpp) line_p *alpp; {
 
        lpp = alpp; madeopt = FALSE;
        while ((*lpp) != (line_p) 0 && ((*lpp)->l_instr&BMASK) != op_lab) {
-               lp = *lpp; next = &lp->l_next;
+               lp = *lpp;
+               if (repl_muls) {
+                       line_p b_repl, e_repl;
+                       int cnt = repl_mul(lp, &b_repl, &e_repl);
+
+                       if (cnt > 0 && cnt <= repl_muls) {
+                               *lpp = b_repl;
+                               e_repl->l_next = lp->l_next->l_next;
+                               oldline(lp->l_next);
+                               oldline(lp);
+                               lp = b_repl;
+                               madeopt = TRUE;
+                       }
+                       else {
+                               while (b_repl != (line_p) 0) {
+                                       line_p n = b_repl->l_next;
+
+                                       oldline(b_repl);
+                                       b_repl = n;
+                               }
+                       }
+               }
+
+               next = &lp->l_next;
                hash[0] = lp->l_instr&BMASK;
                lp=lp->l_next;
                if (lp != (line_p) 0) {
@@ -655,3 +678,131 @@ basicblock(alpp) line_p *alpp; {
        }
        return madeopt;
 }
+
+repl_mul(lp, b, e)
+       register line_p lp;
+       line_p  *b, *e;
+{
+       register line_p next = lp->l_next;
+       int     ins;
+       int     sz;
+       unsigned long   n;
+       int     n0, n1;
+       int     virgin = 1;
+       int     retval = 0;
+
+       *b = 0;
+       if (! next) return 0;
+       if ((ins = (next->l_instr & BMASK)) != op_mli && ins != op_mlu) {
+               return 0;
+       }
+       if ((ins = (lp->l_instr & BMASK)) != op_loc && ins != op_ldc) {
+               return 0;
+       }
+       switch(next->l_optyp) {
+       case OPNO:
+               return 0;
+       case OPSHORT:
+               sz = next->l_a.la_short;
+               break;
+#ifdef LONGOFF
+       case OPOFFSET:
+               sz = next->l_a.la_offset;
+               break;
+#endif
+       default:
+               sz = (next->l_optyp & BMASK) - Z_OPMINI;
+               break;
+       }
+       if (ins == op_loc && sz != wordsize) return 0;
+       if (ins == op_ldc && sz != 2*wordsize) return 0;
+       if (! repl_longmuls && sz != wordsize) return 0;
+       switch(lp->l_optyp) {
+       case OPSHORT:
+               n = (long) lp->l_a.la_short;
+               break;
+#ifdef LONGOFF
+       case OPOFFSET:
+               n = lp->l_a.la_offset;
+               break;
+#endif
+       default:
+               n = (long)((lp->l_optyp & BMASK) - Z_OPMINI);
+               break;
+       }
+
+#define newinstr(res, opcode, val)     (*(res) = newline((short)(val)+Z_OPMINI), (*(res))->l_instr = (opcode))
+
+       while (n) {
+               /* first find "0*1*$" in n */
+               for (n1 = 0; n & 1; n>>=1) ++n1;        /* count "1" bits */
+               if (n)
+                       for (n0 = 0; !(n & 1); n>>=1)   /* count "0" bits */
+                               ++n0;
+               else
+                       n0 = 0;
+
+               if (n1 == 0) {
+                       if (n0) {
+                               newinstr(b, op_loc, n0); b = &((*b)->l_next);
+                               newinstr(b, op_slu, sz); b = &((*b)->l_next);
+                               retval++;
+                       }
+               } else if (n1 == 1) {
+                       if (virgin) {
+                               newinstr(b, op_dup, sz); b = &((*b)->l_next);
+                               virgin = 0;
+                       }
+                       else {
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               newinstr(b, op_dup, 2*sz); b = &((*b)->l_next);
+                               newinstr(b, op_asp, sz); b = &((*b)->l_next);
+                               newinstr(b, op_adu, sz); b = &((*b)->l_next);
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               retval++;
+                       }
+                       if (n) {
+                               newinstr(b, op_loc, n0+n1); b = &((*b)->l_next);
+                               newinstr(b, op_slu, sz); b = &((*b)->l_next);
+                               retval++;
+                       }
+               } else {
+                       if (virgin) {
+                               newinstr(b, op_dup, sz); b = &((*b)->l_next);
+                               newinstr(b, op_loc, 0); b = &((*b)->l_next);
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               virgin = 0;
+                       }
+                       else {
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               newinstr(b, op_dup, 2*sz); b = &((*b)->l_next);
+                               newinstr(b, op_asp, sz); b = &((*b)->l_next);
+                               newinstr(b, op_sbu, sz); b = &((*b)->l_next);
+                               retval++;
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               newinstr(b, op_loc, n1); b = &((*b)->l_next);
+                               newinstr(b, op_slu, sz); b = &((*b)->l_next);
+                               retval++;
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               newinstr(b, op_dup, 2*sz); b = &((*b)->l_next);
+                               newinstr(b, op_asp, sz); b = &((*b)->l_next);
+                               newinstr(b, op_adu, sz); b = &((*b)->l_next);
+                               newinstr(b, op_exg, sz); b = &((*b)->l_next);
+                               retval++;
+                       }
+                       if (n0) {
+                               newinstr(b, op_loc, n0); b = &((*b)->l_next);
+                               newinstr(b, op_slu, sz); b = &((*b)->l_next);
+                               retval++;
+                       }
+               }
+       }
+       newinstr(b, op_asp, sz);
+       if (virgin) {
+               b = &((*b)->l_next);
+               newinstr(b, sz == wordsize ? op_loc : op_ldc, 0);
+       }
+       *e = *b;
+       return retval == 0 ? 1 : retval;
+#undef newinstr
+}

diff --git a/util/opt/proto.make b/util/opt/proto.make
index 1fc06cc..a4b5d55 100644 (file)
--- a/util/opt/proto.make
+++ b/util/opt/proto.make
@@ -23,7 +23,7 @@ CFLAGS= -DNDEBUG $(INCLUDES) $(COPTIONS)
 UCFLAGS= -DNDEBUG $(INCLUDES) $(UCOPTIONS)
 LDFLAGS=$(LDOPTIONS)
 ULDFLAGS=$(ULDOPTIONS)
-LINTFLAGS=$(INCLUDES) -DNDEBUG $(LINTOPTIONS)
+LINTFLAGS=$(INCLUDES) -DNDEBUG -DNORCSID $(LINTOPTIONS)
 CPP=$(UTIL_HOME)/lib.bin/cpp
 
 all:   opt opt2

diff --git a/util/opt/var.c b/util/opt/var.c
index 6f9f70e..ace670a 100644 (file)
--- a/util/opt/var.c
+++ b/util/opt/var.c
@@ -20,6 +20,8 @@ unsigned linecount = 0;               /* "line"number for errormessages */
 int    prodepth  = 0;          /* Level of nesting */
 bool   Lflag     = 0;          /* make library module */
 bool   nflag     = 0;          /* do not optimize */
+int    repl_muls = 0;          /* max # of shifts/adds for replacing muls */
+bool   repl_longmuls = 0;      /* replacing longmuls as well? */
 line_p instrs,pseudos;         /* pointers to chains */
 sym_p  symhash[NSYMHASH];      /* array of pointers to chains */
 FILE   *outfile;