cmd/6c, cmd/8c, cmd/8g: fix print of pc (which is vlong).

While we're at it, fix a wrong for statement in cmd/8g.

LGTM=rsc
R=rsc, golang-codereviews
CC=golang-codereviews
https://golang.org/cl/62700044

src/cmd/6c/reg.c

@@ -1461,7 +1461,7 @@ fixjmp(Reg *firstr)
 	for(r=firstr; r; r=r->link) {
 		p = r->prog;
 		if(debug['R'] && debug['v'])
-			print("%04d %P\n", r->pc, p);
+			print("%04d %P\n", (int)r->pc, p);
 		if(p->as != ACALL && p->to.type == D_BRANCH && r->s2 && r->s2->prog->as == AJMP) {
 			r->s2 = chasejmp(r->s2, &jmploop);
 			p->to.offset = r->s2->pc;
@@ -1486,7 +1486,7 @@ fixjmp(Reg *firstr)
 				// Let it stay.
 			} else {
 				if(debug['R'] && debug['v'])
-					print("del %04d %P\n", r->pc, p);
+					print("del %04d %P\n", (int)r->pc, p);
 				p->as = ANOP;
 			}
 		}
@@ -1499,7 +1499,7 @@ fixjmp(Reg *firstr)
 			p = r->prog;
 			if(p->as == AJMP && p->to.type == D_BRANCH && r->s2 == r->link) {
 				if(debug['R'] && debug['v'])
-					print("del %04d %P\n", r->pc, p);
+					print("del %04d %P\n", (int)r->pc, p);
 				p->as = ANOP;
 			}
 		}
@@ -1520,7 +1520,7 @@ fixjmp(Reg *firstr)
 	if(debug['R'] && debug['v']) {
 		print("\n");
 		for(r=firstr; r; r=r->link)
-			print("%04d %P\n", r->pc, r->prog);
+			print("%04d %P\n", (int)r->pc, r->prog);
 		print("\n");
 	}
 }

src/cmd/8c/reg.c

@@ -558,7 +558,7 @@ brk:
 	if(debug['R'] && debug['v']) {
 		print("after pass 7 (peep)\n");
 		for(r=firstr; r; r=r->link)
-			print("%04d %P\n", r->pc, r->prog);
+			print("%04d %P\n", (int)r->pc, r->prog);
 		print("\n");
 	}
 
@@ -1375,7 +1375,7 @@ fixjmp(Reg *firstr)
 	for(r=firstr; r; r=r->link) {
 		p = r->prog;
 		if(debug['R'] && debug['v'])
-			print("%04d %P\n", r->pc, p);
+			print("%04d %P\n", (int)r->pc, p);
 		if(p->as != ACALL && p->to.type == D_BRANCH && r->s2 && r->s2->prog->as == AJMP) {
 			r->s2 = chasejmp(r->s2, &jmploop);
 			p->to.offset = r->s2->pc;
@@ -1400,7 +1400,7 @@ fixjmp(Reg *firstr)
 				// Let it stay.
 			} else {
 				if(debug['R'] && debug['v'])
-					print("del %04d %P\n", r->pc, p);
+					print("del %04d %P\n", (int)r->pc, p);
 				p->as = ANOP;
 			}
 		}
@@ -1413,7 +1413,7 @@ fixjmp(Reg *firstr)
 			p = r->prog;
 			if(p->as == AJMP && p->to.type == D_BRANCH && r->s2 == r->link) {
 				if(debug['R'] && debug['v'])
-					print("del %04d %P\n", r->pc, p);
+					print("del %04d %P\n", (int)r->pc, p);
 				p->as = ANOP;
 			}
 		}
@@ -1434,7 +1434,7 @@ fixjmp(Reg *firstr)
 	if(debug['R'] && debug['v']) {
 		print("\n");
 		for(r=firstr; r; r=r->link)
-			print("%04d %P\n", r->pc, r->prog);
+			print("%04d %P\n", (int)r->pc, r->prog);
 		print("\n");
 	}
 }

src/cmd/8g/reg.c

@@ -1138,7 +1138,7 @@ dumpit(char *str, Flow *r0, int isreg)
 		r1 = r->p2;
 		if(r1 != nil) {
 			print("	pred:");
-			for(; r1 != nil; r1 = r->p2link)
+			for(; r1 != nil; r1 = r1->p2link)
 				print(" %.4ud", (int)r1->prog->pc);
 			print("\n");
 		}