Change two switches to get casel instruction

SCCS-vsn: old/as.vax/ascode.c 4.7

diff --git a/usr/src/old/as.vax/ascode.c b/usr/src/old/as.vax/ascode.c
index 5de6143..e9de76b 100644 (file)
--- a/usr/src/old/as.vax/ascode.c
+++ b/usr/src/old/as.vax/ascode.c
@@ -1,5 +1,5 @@
 /* Copyright (c) 1980 Regents of the University of California */
 /* Copyright (c) 1980 Regents of the University of California */

-static char sccsid[] = "@(#)ascode.c 4.6 %G%";
+static char sccsid[] = "@(#)ascode.c 4.7 %G%";

 #include <stdio.h>
 #include "as.h"
 #include "assyms.h"
 #include <stdio.h>
 #include "as.h"
 #include "assyms.h"


@@ -64,14 +64,24 @@ insout(op, ap, nact)
            for (ap_walk = ap, i = 1; i <= nact; ap_walk++, i++){
                ap_type = ap_walk->a_atype;
                ap_type_mask = ap_type & AMASK;
            for (ap_walk = ap, i = 1; i <= nact; ap_walk++, i++){
                ap_type = ap_walk->a_atype;
                ap_type_mask = ap_type & AMASK;

-               switch( (fetcharg(ip, i-1)) & ACCESSMASK){      /* type of fp */
-               case ACCB:
+               /*
+                *      The switch value is >> by 3 so that the switch
+                *      code is dense, not implemented as a sequence
+                *      of branches but implemented as a casel.
+                *      In addition, cases ACCI and ACCR are added to force
+                *      dense switch code.
+                */
+               switch( ((fetcharg(ip, i-1)) & ACCESSMASK)>>3){ /* type of fp */
+               case ACCI >> 3:
+               case ACCR >> 3:
+                       break;
+               case ACCB >> 3:

                        if ( !((ap_type_mask == AEXP) || (ap_type_mask == AIMM)) ){
                                yyerror("arg %d, branch displacement must be an expression",i);
                                return;
                        }
                        break;
                        if ( !((ap_type_mask == AEXP) || (ap_type_mask == AIMM)) ){
                                yyerror("arg %d, branch displacement must be an expression",i);
                                return;
                        }
                        break;

-               case ACCA:
+               case ACCA >> 3:

                        switch(ap_type_mask){
                        case AREG:      yyerror("arg %d, addressing a register",i);
                                        return;
                        switch(ap_type_mask){
                        case AREG:      yyerror("arg %d, addressing a register",i);
                                        return;


@@ -81,8 +91,8 @@ insout(op, ap, nact)
                                        }
                        }
                        break;
                                        }
                        }
                        break;

-               case ACCM:
-               case ACCW:
+               case ACCM >> 3:
+               case ACCW >> 3:

                        switch(ap_type_mask){
                        case AIMM:      if (!(ap_type&ASTAR)) {
                                         yyerror("arg %d, modifying a constant",i);
                        switch(ap_type_mask){
                        case AIMM:      if (!(ap_type&ASTAR)) {
                                         yyerror("arg %d, modifying a constant",i);


@@ -140,7 +150,17 @@ putins(op, ap, n)
            argtype = ap->a_atype;
            if (argtype & AINDX)
                dotp->e_xvalue++;
            argtype = ap->a_atype;
            if (argtype & AINDX)
                dotp->e_xvalue++;

+           /*
+            *  This switch has been fixed by enumerating the no action
+            *  alternatives (those that have 1 one byte of code)
+            *  so that a casel instruction is emitted.
+            */

            switch (argtype&~(AINDX|ASTAR)) {
            switch (argtype&~(AINDX|ASTAR)) {

+               case AREG:
+               case ABASE:
+               case ADECR:
+               case AINCR:
+                       break;

                case AEXP: 
                        argtype = fetcharg(itab[op], i);
                        if (argtype == ACCB+TYPB)
                case AEXP: 
                        argtype = fetcharg(itab[op], i);
                        if (argtype == ACCB+TYPB)