From: Bill Joy <bill@ucbvax.Berkeley.EDU>
Date: Fri, 17 Oct 1980 18:00:03 +0000 (-0800)
Subject: Keep up with version 1.83 of jfr fixing dead reg/arg problem.
X-Git-Tag: BSD-4^3~244
X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/commitdiff_plain/35307d3017097e3491aefcb42803d9cb29fb2065?hp=34296e984d5c5b60472ca884055bbe3ab64f7820

Keep up with version 1.83 of jfr fixing dead reg/arg problem.

SCCS-vsn: old/pcc/c2.vax/c21.c 4.2
---

diff --git a/usr/src/old/pcc/c2.vax/c21.c b/usr/src/old/pcc/c2.vax/c21.c
index 84633f6236..f5de6351fb 100644
--- a/usr/src/old/pcc/c2.vax/c21.c
+++ b/usr/src/old/pcc/c2.vax/c21.c
@@ -1,5 +1,5 @@
-static	char sccsid[] = "@(#)c21.c 4.1 %G%";
-/* char C21[] = {"@(#)c21.c 1.82 - 81 ??/??/?? ??:??:?? JFR"}; /* sccs ident */
+static	char sccsid[] = "@(#)c21.c 4.2 %G%";
+/* char C21[] = {"@(#)c21.c 1.83 80/10/16 21:18:22 JFR"}; /* sccs ident */
 
 /*
  * C object code improver-- second part
@@ -614,8 +614,9 @@ register struct node *p;
 	|| OP2==(p->subop>>4) && 0<=(r=isreg(regs[RT2])) && r<NUSE && uses[r]==0) {
 		/* writing a dead register is useless, but watch side effects */
 		switch (p->op) {
+		case ACB:
 		case AOBLEQ: case AOBLSS: case SOBGTR: case SOBGEQ: break;
-		default: if (p->op==ACB) break;
+		default:
 			if (uses[r]==0) {/* no direct uses, check for use of condition codes */
 				register struct node *q=p;
 				while ((q=nonlab(q->forw))->combop==JBR) q=q->ref;	/* cc unused, unchanged */
@@ -644,6 +645,7 @@ register struct node *p;
 		/* check for  r  */
 		if (lastrand!=cp1 && 0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0) {
 			uses[r]=p; cp2=regs[r]; *cp2++=p->subop;
+ 			if (p->op==ASH && preg==(regs+RT1+1)) cp2[-1]=BYTE; /* stupid DEC */
 			if (p->op==MOV || p->op==PUSH || p->op==CVT || p->op==MOVZ || p->op==COM || p->op==NEG) {
 				if (p->op==PUSH) cp1="-(sp)";
 				else {
@@ -654,7 +656,8 @@ register struct node *p;
 					if (p->op!=MOV) cp1=0;
 				}
 				if (cp1) while (*cp2++= *cp1++);
-			} else *cp2++=0;
+ 				else *cp2=0;
+ 			} else *cp2=0;
 			continue;
 		}
 		/* check for (r),(r)+,-(r),[r] */