fixed len/cap for chan. disable gc for now.

go/test: passes 93% (323/345)

R=rsc
http://go/go-review/1015006

src/all-arm.bash

@@ -17,6 +17,10 @@ xcd() {
 	builtin cd $1
 }
 
+# temporarily turn GC off
+# TODO(kaib): reenable GC once everything else works
+export GOGC=off
+
 (xcd ../test
 ./run-arm
 ) || exit $?

src/cmd/5g/cgen.c

@@ -271,7 +271,7 @@ cgen(Node *n, Node *res)
 		break;
 
 	case OLEN:
-		if(istype(nl->type, TMAP)) {
+		if(istype(nl->type, TMAP) || istype(nl->type, TCHAN)) {
 			// map has len in the first 32-bit word.
 			// a zero pointer means zero length
 			regalloc(&n1, types[tptr], res);
@@ -313,6 +313,31 @@ cgen(Node *n, Node *res)
 		break;
 
 	case OCAP:
+		if(istype(nl->type, TCHAN)) {
+			// chan has cap in the second 32-bit word.
+			// a zero pointer means zero length
+			regalloc(&n1, types[tptr], res);
+			cgen(nl, &n1);
+
+			nodconst(&n2, types[tptr], 0);
+			regalloc(&n3, n2.type, N);
+			gmove(&n2, &n3);
+			gcmp(optoas(OCMP, types[tptr]), &n1, &n3);
+			regfree(&n3);
+			p1 = gbranch(optoas(OEQ, types[tptr]), T);
+
+			n2 = n1;
+			n2.op = OINDREG;
+			n2.xoffset = 4;
+			n2.type = types[TINT32];
+			gmove(&n2, &n1);
+
+			patch(p1, pc);
+
+			gmove(&n1, res);
+			regfree(&n1);
+			break;
+		}
 		if(isslice(nl->type)) {
 			regalloc(&n1, types[tptr], res);
 			agen(nl, &n1);

test/arm-pass.txt

@@ -1,3 +1,4 @@
+235.go
 64bit.go
 args.go
 assign.go
@@ -7,8 +8,11 @@ blank1.go
 chan/fifo.go
 chan/goroutines.go
 chan/perm.go
+chan/powser1.go
+chan/powser2.go
 chan/select.go
 chan/sieve.go
+chancap.go
 char_lit.go
 closedchan.go
 closure.go
@@ -256,6 +260,7 @@ interface/returntype.go
 interface/struct.go
 iota.go
 ken/array.go
+ken/chan.go
 ken/chan1.go
 ken/complit.go
 ken/divconst.go
@@ -297,6 +302,7 @@ named.go
 named1.go
 nil.go
 parentype.go
+peano.go
 printbig.go
 range.go
 rename.go