diff --git a/selfhost/cmd/w6c/main.combined.ww b/selfhost/cmd/w6c/main.combined.ww
index 70fda604..32c2820e 100644
--- a/selfhost/cmd/w6c/main.combined.ww
+++ b/selfhost/cmd/w6c/main.combined.ww
@@ -16217,13 +16217,9 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		if (memptype != nil) {
 			let pt: *tinfo = memptype.type_: *tinfo;
 			let pu: *tinfo = pt;
-			for (pu != nil && pu.kind == tykind.TY_NAMED) {
-				pu = pu.under;
-			};
+			pu = tichase(pu);
 			let au: *tinfo = at;
-			for (au != nil && au.kind == tykind.TY_NAMED) {
-				au = au.under;
-			};
+			au = tichase(au);
 			if (pu != nil && pu == au) { same = true; };
 			if (!same && pt != nil && at != nil) {
 				if (typeeq(pt, at)) { same = true; };
@@ -16429,9 +16425,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		// literal/cast forms and loud-stops the rest (#72). Mirrors
 		// cstage cg_widen_tagged_push src_is_tuple.
 		let argtup: *tinfo = arg.type_: *tinfo;
-		for (argtup != nil && argtup.kind == tykind.TY_NAMED) {
-			argtup = argtup.under;
-		};
+		argtup = tichase(argtup);
 		let argistuple: bool = false;
 		if (argtup != nil) {
 			if (argtup.kind == tykind.TY_TUPLE) {
@@ -16538,9 +16532,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		let dotbu: *tinfo = nil;
 		if (base != nil) { if (base.kind == nkind.N_DOT) {
 			dotbu = base.type_: *tinfo;
-			for (dotbu != nil && dotbu.kind == tykind.TY_NAMED) {
-				dotbu = dotbu.under;
-			};
+			dotbu = tichase(dotbu);
 		};};
 		// #60 (alias arc #5): alias-NAMED N_IDENT base — the tnode
 		// reads below see only the N_TNAME leaf (esz 1-sentinel,
@@ -16798,9 +16790,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		let structident: bool = false;
 		if (arg.kind == nkind.N_IDENT) {
 			let st: *tinfo = arg.type_: *tinfo;
-			for (st != nil && st.kind == tykind.TY_NAMED) {
-				st = st.under;
-			};
+			st = tichase(st);
 			if (st != nil) { if (st.kind == tykind.TY_STRUCT) {
 				if (st.size: i32 <= 16) { structident = true; };
 			}; };
@@ -16914,9 +16904,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 			// nodes and literal value exprs. Mirrors the cstage
 			// restage guard.
 			let eti: *tinfo = et.type_: *tinfo;
-			for (eti != nil && eti.kind == tykind.TY_NAMED) {
-				eti = eti.under;
-			};
+			eti = tichase(eti);
 			if (eti != nil) {
 				if (eti.kind == tykind.TY_TUPLE
 				    || eti.kind == tykind.TY_STRUCT
@@ -16983,9 +16971,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 	// register. Mirrors the cstage cgcall guard.
 	{
 		let ati: *tinfo = arg.type_: *tinfo;
-		for (ati != nil && ati.kind == tykind.TY_NAMED) {
-			ati = ati.under;
-		};
+		ati = tichase(ati);
 		if (ati != nil) {
 			if (ati.kind == tykind.TY_TUPLE) {
 				let m32: str = "#32: tuple arg from unsupported source shape (call/ident/literal/unwrap only; rule 7)\n";
@@ -17395,7 +17381,7 @@ fn tichase(t0: *tinfo) *tinfo = {
 // avoid widening the frontend surface for one #156 read-half check.
 fn tinfoisarray(t: *tinfo) bool = {
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	return u.kind == tykind.TY_ARRAY;
 };
@@ -17501,10 +17487,10 @@ export fn localloadop(c: *cgen, tnode: *node) str = {
 // through here. Mirrors cstage idx_eff (cmd/w6c/cgen.c:1163).
 fn idxeffti(t0: *tinfo) *tinfo = {
 	let t: *tinfo = t0;
-	for (t != nil && t.kind == tykind.TY_NAMED) { t = t.under; };
+	t = tichase(t);
 	if (t != nil && t.kind == tykind.TY_PTR) {
 		let p: *tinfo = t.sub;
-		for (p != nil && p.kind == tykind.TY_NAMED) { p = p.under; };
+		p = tichase(p);
 		if (p != nil && p.kind == tykind.TY_ARRAY) { return p; };
 	};
 	return t;
@@ -17790,9 +17776,7 @@ fn structabisize(si: *structinfo) i32 = {
 		if (end > n) { n = end; };
 		if (fi.tnode != nil) {
 			let ti: *tinfo = fi.tnode.type_: *tinfo;
-			for (ti != nil && ti.kind == tykind.TY_NAMED) {
-				ti = ti.under;
-			};
+			ti = tichase(ti);
 			if (ti != nil) {
 				let aln: i32 = ti.align: i32;
 				if (aln > maxaln) { maxaln = aln; };
@@ -17895,7 +17879,7 @@ export fn sretretsize(c: *cgen, t: *node) i32 = {
 	// no float-array-return consumer (structfloatclass stays struct-only).
 	if (r.kind == nkind.N_TARRAY) {
 		let ati: *tinfo = r.type_: *tinfo;
-		for (ati != nil && ati.kind == tykind.TY_NAMED) { ati = ati.under; };
+		ati = tichase(ati);
 		if (ati == nil) { return 0; };
 		let asz: i32 = ati.size: i32;
 		if (asz <= 24) { return 0; };
@@ -18308,7 +18292,7 @@ fn slotsize(c: *cgen, typn: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 8; };
 	let kk: tykind = ti.kind;
 	if (kk == tykind.TY_VOID) { return 0; };
@@ -18346,7 +18330,7 @@ fn fieldsize(c: *cgen, tnode: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 8; };
 	let k: tykind = ti.kind;
 	if (k == tykind.TY_STRUCT) { return ti.slotsize: i32; };
@@ -18603,7 +18587,7 @@ fn structparamsize(c: *cgen, t: *node) i32 = {
 fn aggargsizetn(t: *tinfo) i32 = {
 	if (t == nil) { return 0; };
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return 0; };
 	if (u.kind == tykind.TY_STRUCT || u.kind == tykind.TY_ARRAY) {
 		return u.size: i32;
@@ -18621,7 +18605,7 @@ fn aggargsizetn(t: *tinfo) i32 = {
 fn taggedmemargsize(t: *tinfo) i32 = {
 	if (t == nil) { return 0; };
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return 0; };
 	if (u.kind != tykind.TY_TAGGED) { return 0; };
 	if (u.nullable != 0) { return 0; };
@@ -18644,7 +18628,7 @@ fn nodeisaggarg(n: *node) bool = {
 fn aggargfloatstop(n: *node) bool = {
 	if (n == nil) { return false; };
 	let st: *tinfo = n.type_: *tinfo;
-	for (st != nil && st.kind == tykind.TY_NAMED) { st = st.under; };
+	st = tichase(st);
 	if (st == nil) { return false; };
 	if (st.kind != tykind.TY_STRUCT) { return false; };
 	if (st.size: i32 > 16) { return false; };
@@ -18750,7 +18734,7 @@ fn istaggedtype(c: *cgen, t: *node) bool = {
 fn tnodeisagg(t: *node) bool = {
 	if (t == nil) { return false; };
 	let u: *tinfo = t.type_: *tinfo;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	if (u.kind == tykind.TY_STRUCT) { return true; };
 	if (u.kind == tykind.TY_ARRAY) { return true; };
@@ -18796,7 +18780,7 @@ export fn nullableptrtag(t: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 0; };
 	if (ti.kind != tykind.TY_TAGGED) { return 0; };
 	let p: *tparam = ti.params;
@@ -18858,7 +18842,7 @@ fn taggedvariantindext(c: *cgen, du: *tinfo, rhs: *node) i32 = {
 	if (du == nil)  { return -1; };
 	if (rhs == nil) { return -1; };
 	let ti: *tinfo = du;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	let r: i32 = flatvariantidxt(ti, rhs.type_: *tinfo);
@@ -18918,7 +18902,7 @@ fn flatvariantidx(c: *cgen, tagged: *node, pat: *node) i32 = {
 fn flatvariantidxt(tagged: *tinfo, want: *tinfo) i32 = {
 	if (want == nil) { return -1; };
 	let ti: *tinfo = tagged;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	// Pass 1: exact match (NAMED-vs-NAMED typeeq, tagged-vs-tagged, bare
@@ -19060,9 +19044,9 @@ fn cgvariantmatch(vt: *tinfo, want: *tinfo) bool = {
 	};
 	if (vt.kind == tykind.TY_NAMED || want.kind == tykind.TY_NAMED) {
 		let vu: *tinfo = vt;
-		for (vu != nil && vu.kind == tykind.TY_NAMED) { vu = vu.under; };
+		vu = tichase(vu);
 		let wu: *tinfo = want;
-		for (wu != nil && wu.kind == tykind.TY_NAMED) { wu = wu.under; };
+		wu = tichase(wu);
 		if (vu != nil && wu != nil
 		    && vu.kind == tykind.TY_TAGGED
 		    && wu.kind == tykind.TY_TAGGED) {
@@ -19080,9 +19064,9 @@ fn cgvariantmatch(vt: *tinfo, want: *tinfo) bool = {
 // cstage cg_variant_struct_match (cmd/w6c/cgen.c).
 fn cgvariantstructmatch(vt: *tinfo, want: *tinfo) bool = {
 	let vu: *tinfo = vt;
-	for (vu != nil && vu.kind == tykind.TY_NAMED) { vu = vu.under; };
+	vu = tichase(vu);
 	let wu: *tinfo = want;
-	for (wu != nil && wu.kind == tykind.TY_NAMED) { wu = wu.under; };
+	wu = tichase(wu);
 	if (vu == nil) { return false; };
 	if (wu == nil) { return false; };
 	return typeeq(vu, wu);
@@ -19102,7 +19086,7 @@ fn cgvariantstructmatch(vt: *tinfo, want: *tinfo) bool = {
 fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 	if (tagged == nil) { return -1; };
 	let ti: *tinfo = tagged.type_: *tinfo;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	let want: *tinfo = nil;
@@ -19117,7 +19101,7 @@ fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 				if (fallback < 0) { fallback = idx; };
 				if (want != nil) {
 					let su: *tinfo = vt;
-					for (su != nil && su.kind == tykind.TY_NAMED) { su = su.under; };
+					su = tichase(su);
 					if (su != nil) {
 						if (typeeq(su.sub, want)) { return idx; };
 					};
@@ -19140,11 +19124,11 @@ fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 // (cmd/w6c/cgen.c:1177) over su->params + cg_tag_for_variant (:503).
 fn cgwidentagremap(c: *cgen, du: *tinfo, su: *tinfo, slot_off: i32) void = {
 	let dt: *tinfo = du;
-	for (dt != nil && dt.kind == tykind.TY_NAMED) { dt = dt.under; };
+	dt = tichase(dt);
 	if (dt == nil) { return; };
 	if (dt.kind != tykind.TY_TAGGED) { return; };
 	let st: *tinfo = su;
-	for (st != nil && st.kind == tykind.TY_NAMED) { st = st.under; };
+	st = tichase(st);
 	if (st == nil) { return; };
 	if (st.kind != tykind.TY_TAGGED) { return; };
 	let identity: bool = true;
@@ -19316,7 +19300,7 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 	if (e == nil) { return false; };
 	if (e.kind == nkind.N_UN && e.op == tkind.TK_STAR) {
 		let du: *tinfo = e.type_: *tinfo;
-		for (du != nil && du.kind == tykind.TY_NAMED) { du = du.under; };
+		du = tichase(du);
 		if (du == nil) { return false; };
 		if (du.kind != tykind.TY_TAGGED) { return false; };
 		if (du.nullable != 0) { return false; };
@@ -19324,7 +19308,7 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 	};
 	if (e.kind != nkind.N_INDEX && e.kind != nkind.N_DOT) { return false; };
 	let u: *tinfo = e.type_: *tinfo;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	if (u.kind != tykind.TY_TAGGED) { return false; };
 	return u.size: i32 > TUPLE_GPCAP * 8;
@@ -19341,12 +19325,12 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 fn taggedcastpeel(c: *cgen, e: *node) *node = {
 	for (e != nil && e.kind == nkind.N_CAST && e.lhs != nil) {
 		let cu: *tinfo = e.type_: *tinfo;
-		for (cu != nil && cu.kind == tykind.TY_NAMED) { cu = cu.under; };
+		cu = tichase(cu);
 		if (cu == nil) { return e; };
 		if (cu.kind != tykind.TY_TAGGED) { return e; };
 		if (cu.nullable != 0) { return e; };
 		let iu: *tinfo = e.lhs.type_: *tinfo;
-		for (iu != nil && iu.kind == tykind.TY_NAMED) { iu = iu.under; };
+		iu = tichase(iu);
 		if (iu == nil) { return e; };
 		if (iu.kind != tykind.TY_TAGGED) { return e; };
 		if (iu.nullable != 0) { return e; };
@@ -19365,7 +19349,7 @@ fn taggedidcastpeel(c: *cgen, e: *node) *node = {
 	for (e != nil && e.kind == nkind.N_CAST && e.lhs != nil) {
 		if (!typeeq(e.type_: *tinfo, e.lhs.type_: *tinfo)) { return e; };
 		let cu: *tinfo = e.type_: *tinfo;
-		for (cu != nil && cu.kind == tykind.TY_NAMED) { cu = cu.under; };
+		cu = tichase(cu);
 		if (cu == nil) { return e; };
 		if (cu.kind != tykind.TY_TAGGED) { return e; };
 		e = e.lhs;
@@ -20315,16 +20299,12 @@ export fn dotchainresolve(c: *cgen, n: *node,
     // (plus one TY_PTR hop for a `*struct` root). tfield.type_ then
     // supplies each nested struct directly, so no name re-lookup.
     let curstruct: *tinfo = cur.type_: *tinfo;
-    for (curstruct != nil && curstruct.kind == tykind.TY_NAMED) {
-        curstruct = curstruct.under;
-    };
+    curstruct = tichase(curstruct);
     if (*outptrroot) {
         if (curstruct == nil) { return false; };
         if (curstruct.kind != tykind.TY_PTR) { return false; };
         curstruct = curstruct.sub;
-        for (curstruct != nil && curstruct.kind == tykind.TY_NAMED) {
-            curstruct = curstruct.under;
-        };
+        curstruct = tichase(curstruct);
     };
     let i: i32 = nsteps - 1;
     for (i >= 0) {
@@ -20346,7 +20326,7 @@ export fn dotchainresolve(c: *cgen, n: *node,
             return true;
         };
         let ft: *tinfo = found.type_;
-        for (ft != nil && ft.kind == tykind.TY_NAMED) { ft = ft.under; };
+        ft = tichase(ft);
         if (ft == nil) { return false; };
         if (ft.kind == tykind.TY_STR) {
             // str IS []u8: .cap is the third header word, same as
@@ -20891,9 +20871,7 @@ fn cgstructlitfill(c: *cgen, si: *structinfo, lit: *node,
                         let agsz49: i32 = 0;
                         if (fi.tnode != nil) {
                             let agti49: *tinfo = fi.tnode.type_: *tinfo;
-                            for (agti49 != nil && agti49.kind == tykind.TY_NAMED) {
-                                agti49 = agti49.under;
-                            };
+                            agti49 = tichase(agti49);
                             if (agti49 != nil) { agsz49 = agti49.size: i32; };
                         };
                         aggcopy(c, agsz49);
diff --git a/selfhost/cmd/wcc/cgenutil.ww b/selfhost/cmd/wcc/cgenutil.ww
index dc853c19..6e5b6dc7 100644
--- a/selfhost/cmd/wcc/cgenutil.ww
+++ b/selfhost/cmd/wcc/cgenutil.ww
@@ -145,13 +145,9 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		if (memptype != nil) {
 			let pt: *tinfo = memptype.type_: *tinfo;
 			let pu: *tinfo = pt;
-			for (pu != nil && pu.kind == tykind.TY_NAMED) {
-				pu = pu.under;
-			};
+			pu = tichase(pu);
 			let au: *tinfo = at;
-			for (au != nil && au.kind == tykind.TY_NAMED) {
-				au = au.under;
-			};
+			au = tichase(au);
 			if (pu != nil && pu == au) { same = true; };
 			if (!same && pt != nil && at != nil) {
 				if (typeeq(pt, at)) { same = true; };
@@ -357,9 +353,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		// literal/cast forms and loud-stops the rest (#72). Mirrors
 		// cstage cg_widen_tagged_push src_is_tuple.
 		let argtup: *tinfo = arg.type_: *tinfo;
-		for (argtup != nil && argtup.kind == tykind.TY_NAMED) {
-			argtup = argtup.under;
-		};
+		argtup = tichase(argtup);
 		let argistuple: bool = false;
 		if (argtup != nil) {
 			if (argtup.kind == tykind.TY_TUPLE) {
@@ -466,9 +460,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		let dotbu: *tinfo = nil;
 		if (base != nil) { if (base.kind == nkind.N_DOT) {
 			dotbu = base.type_: *tinfo;
-			for (dotbu != nil && dotbu.kind == tykind.TY_NAMED) {
-				dotbu = dotbu.under;
-			};
+			dotbu = tichase(dotbu);
 		};};
 		// #60 (alias arc #5): alias-NAMED N_IDENT base — the tnode
 		// reads below see only the N_TNAME leaf (esz 1-sentinel,
@@ -726,9 +718,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		let structident: bool = false;
 		if (arg.kind == nkind.N_IDENT) {
 			let st: *tinfo = arg.type_: *tinfo;
-			for (st != nil && st.kind == tykind.TY_NAMED) {
-				st = st.under;
-			};
+			st = tichase(st);
 			if (st != nil) { if (st.kind == tykind.TY_STRUCT) {
 				if (st.size: i32 <= 16) { structident = true; };
 			}; };
@@ -842,9 +832,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 			// nodes and literal value exprs. Mirrors the cstage
 			// restage guard.
 			let eti: *tinfo = et.type_: *tinfo;
-			for (eti != nil && eti.kind == tykind.TY_NAMED) {
-				eti = eti.under;
-			};
+			eti = tichase(eti);
 			if (eti != nil) {
 				if (eti.kind == tykind.TY_TUPLE
 				    || eti.kind == tykind.TY_STRUCT
@@ -911,9 +899,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 	// register. Mirrors the cstage cgcall guard.
 	{
 		let ati: *tinfo = arg.type_: *tinfo;
-		for (ati != nil && ati.kind == tykind.TY_NAMED) {
-			ati = ati.under;
-		};
+		ati = tichase(ati);
 		if (ati != nil) {
 			if (ati.kind == tykind.TY_TUPLE) {
 				let m32: str = "#32: tuple arg from unsupported source shape (call/ident/literal/unwrap only; rule 7)\n";
@@ -1323,7 +1309,7 @@ fn tichase(t0: *tinfo) *tinfo = {
 // avoid widening the frontend surface for one #156 read-half check.
 fn tinfoisarray(t: *tinfo) bool = {
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	return u.kind == tykind.TY_ARRAY;
 };
@@ -1429,10 +1415,10 @@ export fn localloadop(c: *cgen, tnode: *node) str = {
 // through here. Mirrors cstage idx_eff (cmd/w6c/cgen.c:1163).
 fn idxeffti(t0: *tinfo) *tinfo = {
 	let t: *tinfo = t0;
-	for (t != nil && t.kind == tykind.TY_NAMED) { t = t.under; };
+	t = tichase(t);
 	if (t != nil && t.kind == tykind.TY_PTR) {
 		let p: *tinfo = t.sub;
-		for (p != nil && p.kind == tykind.TY_NAMED) { p = p.under; };
+		p = tichase(p);
 		if (p != nil && p.kind == tykind.TY_ARRAY) { return p; };
 	};
 	return t;
@@ -1718,9 +1704,7 @@ fn structabisize(si: *structinfo) i32 = {
 		if (end > n) { n = end; };
 		if (fi.tnode != nil) {
 			let ti: *tinfo = fi.tnode.type_: *tinfo;
-			for (ti != nil && ti.kind == tykind.TY_NAMED) {
-				ti = ti.under;
-			};
+			ti = tichase(ti);
 			if (ti != nil) {
 				let aln: i32 = ti.align: i32;
 				if (aln > maxaln) { maxaln = aln; };
@@ -1823,7 +1807,7 @@ export fn sretretsize(c: *cgen, t: *node) i32 = {
 	// no float-array-return consumer (structfloatclass stays struct-only).
 	if (r.kind == nkind.N_TARRAY) {
 		let ati: *tinfo = r.type_: *tinfo;
-		for (ati != nil && ati.kind == tykind.TY_NAMED) { ati = ati.under; };
+		ati = tichase(ati);
 		if (ati == nil) { return 0; };
 		let asz: i32 = ati.size: i32;
 		if (asz <= 24) { return 0; };
@@ -2236,7 +2220,7 @@ fn slotsize(c: *cgen, typn: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 8; };
 	let kk: tykind = ti.kind;
 	if (kk == tykind.TY_VOID) { return 0; };
@@ -2274,7 +2258,7 @@ fn fieldsize(c: *cgen, tnode: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 8; };
 	let k: tykind = ti.kind;
 	if (k == tykind.TY_STRUCT) { return ti.slotsize: i32; };
@@ -2531,7 +2515,7 @@ fn structparamsize(c: *cgen, t: *node) i32 = {
 fn aggargsizetn(t: *tinfo) i32 = {
 	if (t == nil) { return 0; };
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return 0; };
 	if (u.kind == tykind.TY_STRUCT || u.kind == tykind.TY_ARRAY) {
 		return u.size: i32;
@@ -2549,7 +2533,7 @@ fn aggargsizetn(t: *tinfo) i32 = {
 fn taggedmemargsize(t: *tinfo) i32 = {
 	if (t == nil) { return 0; };
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return 0; };
 	if (u.kind != tykind.TY_TAGGED) { return 0; };
 	if (u.nullable != 0) { return 0; };
@@ -2572,7 +2556,7 @@ fn nodeisaggarg(n: *node) bool = {
 fn aggargfloatstop(n: *node) bool = {
 	if (n == nil) { return false; };
 	let st: *tinfo = n.type_: *tinfo;
-	for (st != nil && st.kind == tykind.TY_NAMED) { st = st.under; };
+	st = tichase(st);
 	if (st == nil) { return false; };
 	if (st.kind != tykind.TY_STRUCT) { return false; };
 	if (st.size: i32 > 16) { return false; };
@@ -2678,7 +2662,7 @@ fn istaggedtype(c: *cgen, t: *node) bool = {
 fn tnodeisagg(t: *node) bool = {
 	if (t == nil) { return false; };
 	let u: *tinfo = t.type_: *tinfo;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	if (u.kind == tykind.TY_STRUCT) { return true; };
 	if (u.kind == tykind.TY_ARRAY) { return true; };
@@ -2724,7 +2708,7 @@ export fn nullableptrtag(t: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 0; };
 	if (ti.kind != tykind.TY_TAGGED) { return 0; };
 	let p: *tparam = ti.params;
@@ -2786,7 +2770,7 @@ fn taggedvariantindext(c: *cgen, du: *tinfo, rhs: *node) i32 = {
 	if (du == nil)  { return -1; };
 	if (rhs == nil) { return -1; };
 	let ti: *tinfo = du;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	let r: i32 = flatvariantidxt(ti, rhs.type_: *tinfo);
@@ -2846,7 +2830,7 @@ fn flatvariantidx(c: *cgen, tagged: *node, pat: *node) i32 = {
 fn flatvariantidxt(tagged: *tinfo, want: *tinfo) i32 = {
 	if (want == nil) { return -1; };
 	let ti: *tinfo = tagged;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	// Pass 1: exact match (NAMED-vs-NAMED typeeq, tagged-vs-tagged, bare
@@ -2988,9 +2972,9 @@ fn cgvariantmatch(vt: *tinfo, want: *tinfo) bool = {
 	};
 	if (vt.kind == tykind.TY_NAMED || want.kind == tykind.TY_NAMED) {
 		let vu: *tinfo = vt;
-		for (vu != nil && vu.kind == tykind.TY_NAMED) { vu = vu.under; };
+		vu = tichase(vu);
 		let wu: *tinfo = want;
-		for (wu != nil && wu.kind == tykind.TY_NAMED) { wu = wu.under; };
+		wu = tichase(wu);
 		if (vu != nil && wu != nil
 		    && vu.kind == tykind.TY_TAGGED
 		    && wu.kind == tykind.TY_TAGGED) {
@@ -3008,9 +2992,9 @@ fn cgvariantmatch(vt: *tinfo, want: *tinfo) bool = {
 // cstage cg_variant_struct_match (cmd/w6c/cgen.c).
 fn cgvariantstructmatch(vt: *tinfo, want: *tinfo) bool = {
 	let vu: *tinfo = vt;
-	for (vu != nil && vu.kind == tykind.TY_NAMED) { vu = vu.under; };
+	vu = tichase(vu);
 	let wu: *tinfo = want;
-	for (wu != nil && wu.kind == tykind.TY_NAMED) { wu = wu.under; };
+	wu = tichase(wu);
 	if (vu == nil) { return false; };
 	if (wu == nil) { return false; };
 	return typeeq(vu, wu);
@@ -3030,7 +3014,7 @@ fn cgvariantstructmatch(vt: *tinfo, want: *tinfo) bool = {
 fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 	if (tagged == nil) { return -1; };
 	let ti: *tinfo = tagged.type_: *tinfo;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	let want: *tinfo = nil;
@@ -3045,7 +3029,7 @@ fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 				if (fallback < 0) { fallback = idx; };
 				if (want != nil) {
 					let su: *tinfo = vt;
-					for (su != nil && su.kind == tykind.TY_NAMED) { su = su.under; };
+					su = tichase(su);
 					if (su != nil) {
 						if (typeeq(su.sub, want)) { return idx; };
 					};
@@ -3068,11 +3052,11 @@ fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 // (cmd/w6c/cgen.c:1177) over su->params + cg_tag_for_variant (:503).
 fn cgwidentagremap(c: *cgen, du: *tinfo, su: *tinfo, slot_off: i32) void = {
 	let dt: *tinfo = du;
-	for (dt != nil && dt.kind == tykind.TY_NAMED) { dt = dt.under; };
+	dt = tichase(dt);
 	if (dt == nil) { return; };
 	if (dt.kind != tykind.TY_TAGGED) { return; };
 	let st: *tinfo = su;
-	for (st != nil && st.kind == tykind.TY_NAMED) { st = st.under; };
+	st = tichase(st);
 	if (st == nil) { return; };
 	if (st.kind != tykind.TY_TAGGED) { return; };
 	let identity: bool = true;
@@ -3244,7 +3228,7 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 	if (e == nil) { return false; };
 	if (e.kind == nkind.N_UN && e.op == tkind.TK_STAR) {
 		let du: *tinfo = e.type_: *tinfo;
-		for (du != nil && du.kind == tykind.TY_NAMED) { du = du.under; };
+		du = tichase(du);
 		if (du == nil) { return false; };
 		if (du.kind != tykind.TY_TAGGED) { return false; };
 		if (du.nullable != 0) { return false; };
@@ -3252,7 +3236,7 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 	};
 	if (e.kind != nkind.N_INDEX && e.kind != nkind.N_DOT) { return false; };
 	let u: *tinfo = e.type_: *tinfo;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	if (u.kind != tykind.TY_TAGGED) { return false; };
 	return u.size: i32 > TUPLE_GPCAP * 8;
@@ -3269,12 +3253,12 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 fn taggedcastpeel(c: *cgen, e: *node) *node = {
 	for (e != nil && e.kind == nkind.N_CAST && e.lhs != nil) {
 		let cu: *tinfo = e.type_: *tinfo;
-		for (cu != nil && cu.kind == tykind.TY_NAMED) { cu = cu.under; };
+		cu = tichase(cu);
 		if (cu == nil) { return e; };
 		if (cu.kind != tykind.TY_TAGGED) { return e; };
 		if (cu.nullable != 0) { return e; };
 		let iu: *tinfo = e.lhs.type_: *tinfo;
-		for (iu != nil && iu.kind == tykind.TY_NAMED) { iu = iu.under; };
+		iu = tichase(iu);
 		if (iu == nil) { return e; };
 		if (iu.kind != tykind.TY_TAGGED) { return e; };
 		if (iu.nullable != 0) { return e; };
@@ -3293,7 +3277,7 @@ fn taggedidcastpeel(c: *cgen, e: *node) *node = {
 	for (e != nil && e.kind == nkind.N_CAST && e.lhs != nil) {
 		if (!typeeq(e.type_: *tinfo, e.lhs.type_: *tinfo)) { return e; };
 		let cu: *tinfo = e.type_: *tinfo;
-		for (cu != nil && cu.kind == tykind.TY_NAMED) { cu = cu.under; };
+		cu = tichase(cu);
 		if (cu == nil) { return e; };
 		if (cu.kind != tykind.TY_TAGGED) { return e; };
 		e = e.lhs;
@@ -4243,16 +4227,12 @@ export fn dotchainresolve(c: *cgen, n: *node,
     // (plus one TY_PTR hop for a `*struct` root). tfield.type_ then
     // supplies each nested struct directly, so no name re-lookup.
     let curstruct: *tinfo = cur.type_: *tinfo;
-    for (curstruct != nil && curstruct.kind == tykind.TY_NAMED) {
-        curstruct = curstruct.under;
-    };
+    curstruct = tichase(curstruct);
     if (*outptrroot) {
         if (curstruct == nil) { return false; };
         if (curstruct.kind != tykind.TY_PTR) { return false; };
         curstruct = curstruct.sub;
-        for (curstruct != nil && curstruct.kind == tykind.TY_NAMED) {
-            curstruct = curstruct.under;
-        };
+        curstruct = tichase(curstruct);
     };
     let i: i32 = nsteps - 1;
     for (i >= 0) {
@@ -4274,7 +4254,7 @@ export fn dotchainresolve(c: *cgen, n: *node,
             return true;
         };
         let ft: *tinfo = found.type_;
-        for (ft != nil && ft.kind == tykind.TY_NAMED) { ft = ft.under; };
+        ft = tichase(ft);
         if (ft == nil) { return false; };
         if (ft.kind == tykind.TY_STR) {
             // str IS []u8: .cap is the third header word, same as
@@ -4819,9 +4799,7 @@ fn cgstructlitfill(c: *cgen, si: *structinfo, lit: *node,
                         let agsz49: i32 = 0;
                         if (fi.tnode != nil) {
                             let agti49: *tinfo = fi.tnode.type_: *tinfo;
-                            for (agti49 != nil && agti49.kind == tykind.TY_NAMED) {
-                                agti49 = agti49.under;
-                            };
+                            agti49 = tichase(agti49);
                             if (agti49 != nil) { agsz49 = agti49.size: i32; };
                         };
                         aggcopy(c, agsz49);
diff --git a/selfhost/cmd/wwdump/main.combined.ww b/selfhost/cmd/wwdump/main.combined.ww
index 8f49b20c..fbf48492 100644
--- a/selfhost/cmd/wwdump/main.combined.ww
+++ b/selfhost/cmd/wwdump/main.combined.ww
@@ -16217,13 +16217,9 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		if (memptype != nil) {
 			let pt: *tinfo = memptype.type_: *tinfo;
 			let pu: *tinfo = pt;
-			for (pu != nil && pu.kind == tykind.TY_NAMED) {
-				pu = pu.under;
-			};
+			pu = tichase(pu);
 			let au: *tinfo = at;
-			for (au != nil && au.kind == tykind.TY_NAMED) {
-				au = au.under;
-			};
+			au = tichase(au);
 			if (pu != nil && pu == au) { same = true; };
 			if (!same && pt != nil && at != nil) {
 				if (typeeq(pt, at)) { same = true; };
@@ -16429,9 +16425,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		// literal/cast forms and loud-stops the rest (#72). Mirrors
 		// cstage cg_widen_tagged_push src_is_tuple.
 		let argtup: *tinfo = arg.type_: *tinfo;
-		for (argtup != nil && argtup.kind == tykind.TY_NAMED) {
-			argtup = argtup.under;
-		};
+		argtup = tichase(argtup);
 		let argistuple: bool = false;
 		if (argtup != nil) {
 			if (argtup.kind == tykind.TY_TUPLE) {
@@ -16538,9 +16532,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		let dotbu: *tinfo = nil;
 		if (base != nil) { if (base.kind == nkind.N_DOT) {
 			dotbu = base.type_: *tinfo;
-			for (dotbu != nil && dotbu.kind == tykind.TY_NAMED) {
-				dotbu = dotbu.under;
-			};
+			dotbu = tichase(dotbu);
 		};};
 		// #60 (alias arc #5): alias-NAMED N_IDENT base — the tnode
 		// reads below see only the N_TNAME leaf (esz 1-sentinel,
@@ -16798,9 +16790,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 		let structident: bool = false;
 		if (arg.kind == nkind.N_IDENT) {
 			let st: *tinfo = arg.type_: *tinfo;
-			for (st != nil && st.kind == tykind.TY_NAMED) {
-				st = st.under;
-			};
+			st = tichase(st);
 			if (st != nil) { if (st.kind == tykind.TY_STRUCT) {
 				if (st.size: i32 <= 16) { structident = true; };
 			}; };
@@ -16914,9 +16904,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 			// nodes and literal value exprs. Mirrors the cstage
 			// restage guard.
 			let eti: *tinfo = et.type_: *tinfo;
-			for (eti != nil && eti.kind == tykind.TY_NAMED) {
-				eti = eti.under;
-			};
+			eti = tichase(eti);
 			if (eti != nil) {
 				if (eti.kind == tykind.TY_TUPLE
 				    || eti.kind == tykind.TY_STRUCT
@@ -16983,9 +16971,7 @@ fn pushargsrev(c: *cgen, arg: *node, param: *node, memphase: bool) i32 = {
 	// register. Mirrors the cstage cgcall guard.
 	{
 		let ati: *tinfo = arg.type_: *tinfo;
-		for (ati != nil && ati.kind == tykind.TY_NAMED) {
-			ati = ati.under;
-		};
+		ati = tichase(ati);
 		if (ati != nil) {
 			if (ati.kind == tykind.TY_TUPLE) {
 				let m32: str = "#32: tuple arg from unsupported source shape (call/ident/literal/unwrap only; rule 7)\n";
@@ -17395,7 +17381,7 @@ fn tichase(t0: *tinfo) *tinfo = {
 // avoid widening the frontend surface for one #156 read-half check.
 fn tinfoisarray(t: *tinfo) bool = {
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	return u.kind == tykind.TY_ARRAY;
 };
@@ -17501,10 +17487,10 @@ export fn localloadop(c: *cgen, tnode: *node) str = {
 // through here. Mirrors cstage idx_eff (cmd/w6c/cgen.c:1163).
 fn idxeffti(t0: *tinfo) *tinfo = {
 	let t: *tinfo = t0;
-	for (t != nil && t.kind == tykind.TY_NAMED) { t = t.under; };
+	t = tichase(t);
 	if (t != nil && t.kind == tykind.TY_PTR) {
 		let p: *tinfo = t.sub;
-		for (p != nil && p.kind == tykind.TY_NAMED) { p = p.under; };
+		p = tichase(p);
 		if (p != nil && p.kind == tykind.TY_ARRAY) { return p; };
 	};
 	return t;
@@ -17790,9 +17776,7 @@ fn structabisize(si: *structinfo) i32 = {
 		if (end > n) { n = end; };
 		if (fi.tnode != nil) {
 			let ti: *tinfo = fi.tnode.type_: *tinfo;
-			for (ti != nil && ti.kind == tykind.TY_NAMED) {
-				ti = ti.under;
-			};
+			ti = tichase(ti);
 			if (ti != nil) {
 				let aln: i32 = ti.align: i32;
 				if (aln > maxaln) { maxaln = aln; };
@@ -17895,7 +17879,7 @@ export fn sretretsize(c: *cgen, t: *node) i32 = {
 	// no float-array-return consumer (structfloatclass stays struct-only).
 	if (r.kind == nkind.N_TARRAY) {
 		let ati: *tinfo = r.type_: *tinfo;
-		for (ati != nil && ati.kind == tykind.TY_NAMED) { ati = ati.under; };
+		ati = tichase(ati);
 		if (ati == nil) { return 0; };
 		let asz: i32 = ati.size: i32;
 		if (asz <= 24) { return 0; };
@@ -18308,7 +18292,7 @@ fn slotsize(c: *cgen, typn: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 8; };
 	let kk: tykind = ti.kind;
 	if (kk == tykind.TY_VOID) { return 0; };
@@ -18346,7 +18330,7 @@ fn fieldsize(c: *cgen, tnode: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 8; };
 	let k: tykind = ti.kind;
 	if (k == tykind.TY_STRUCT) { return ti.slotsize: i32; };
@@ -18603,7 +18587,7 @@ fn structparamsize(c: *cgen, t: *node) i32 = {
 fn aggargsizetn(t: *tinfo) i32 = {
 	if (t == nil) { return 0; };
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return 0; };
 	if (u.kind == tykind.TY_STRUCT || u.kind == tykind.TY_ARRAY) {
 		return u.size: i32;
@@ -18621,7 +18605,7 @@ fn aggargsizetn(t: *tinfo) i32 = {
 fn taggedmemargsize(t: *tinfo) i32 = {
 	if (t == nil) { return 0; };
 	let u: *tinfo = t;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return 0; };
 	if (u.kind != tykind.TY_TAGGED) { return 0; };
 	if (u.nullable != 0) { return 0; };
@@ -18644,7 +18628,7 @@ fn nodeisaggarg(n: *node) bool = {
 fn aggargfloatstop(n: *node) bool = {
 	if (n == nil) { return false; };
 	let st: *tinfo = n.type_: *tinfo;
-	for (st != nil && st.kind == tykind.TY_NAMED) { st = st.under; };
+	st = tichase(st);
 	if (st == nil) { return false; };
 	if (st.kind != tykind.TY_STRUCT) { return false; };
 	if (st.size: i32 > 16) { return false; };
@@ -18750,7 +18734,7 @@ fn istaggedtype(c: *cgen, t: *node) bool = {
 fn tnodeisagg(t: *node) bool = {
 	if (t == nil) { return false; };
 	let u: *tinfo = t.type_: *tinfo;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	if (u.kind == tykind.TY_STRUCT) { return true; };
 	if (u.kind == tykind.TY_ARRAY) { return true; };
@@ -18796,7 +18780,7 @@ export fn nullableptrtag(t: *node) i32 = {
 	// #64 builds per-decl NAMED wrappers (tinfofornode), so the peel
 	// now fires on aliased operands; byte-id holds because it collapses
 	// NAMED to the alias-invariant underlying this read consumes.
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return 0; };
 	if (ti.kind != tykind.TY_TAGGED) { return 0; };
 	let p: *tparam = ti.params;
@@ -18858,7 +18842,7 @@ fn taggedvariantindext(c: *cgen, du: *tinfo, rhs: *node) i32 = {
 	if (du == nil)  { return -1; };
 	if (rhs == nil) { return -1; };
 	let ti: *tinfo = du;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	let r: i32 = flatvariantidxt(ti, rhs.type_: *tinfo);
@@ -18918,7 +18902,7 @@ fn flatvariantidx(c: *cgen, tagged: *node, pat: *node) i32 = {
 fn flatvariantidxt(tagged: *tinfo, want: *tinfo) i32 = {
 	if (want == nil) { return -1; };
 	let ti: *tinfo = tagged;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	// Pass 1: exact match (NAMED-vs-NAMED typeeq, tagged-vs-tagged, bare
@@ -19060,9 +19044,9 @@ fn cgvariantmatch(vt: *tinfo, want: *tinfo) bool = {
 	};
 	if (vt.kind == tykind.TY_NAMED || want.kind == tykind.TY_NAMED) {
 		let vu: *tinfo = vt;
-		for (vu != nil && vu.kind == tykind.TY_NAMED) { vu = vu.under; };
+		vu = tichase(vu);
 		let wu: *tinfo = want;
-		for (wu != nil && wu.kind == tykind.TY_NAMED) { wu = wu.under; };
+		wu = tichase(wu);
 		if (vu != nil && wu != nil
 		    && vu.kind == tykind.TY_TAGGED
 		    && wu.kind == tykind.TY_TAGGED) {
@@ -19080,9 +19064,9 @@ fn cgvariantmatch(vt: *tinfo, want: *tinfo) bool = {
 // cstage cg_variant_struct_match (cmd/w6c/cgen.c).
 fn cgvariantstructmatch(vt: *tinfo, want: *tinfo) bool = {
 	let vu: *tinfo = vt;
-	for (vu != nil && vu.kind == tykind.TY_NAMED) { vu = vu.under; };
+	vu = tichase(vu);
 	let wu: *tinfo = want;
-	for (wu != nil && wu.kind == tykind.TY_NAMED) { wu = wu.under; };
+	wu = tichase(wu);
 	if (vu == nil) { return false; };
 	if (wu == nil) { return false; };
 	return typeeq(vu, wu);
@@ -19102,7 +19086,7 @@ fn cgvariantstructmatch(vt: *tinfo, want: *tinfo) bool = {
 fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 	if (tagged == nil) { return -1; };
 	let ti: *tinfo = tagged.type_: *tinfo;
-	for (ti != nil && ti.kind == tykind.TY_NAMED) { ti = ti.under; };
+	ti = tichase(ti);
 	if (ti == nil) { return -1; };
 	if (ti.kind != tykind.TY_TAGGED) { return -1; };
 	let want: *tinfo = nil;
@@ -19117,7 +19101,7 @@ fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 				if (fallback < 0) { fallback = idx; };
 				if (want != nil) {
 					let su: *tinfo = vt;
-					for (su != nil && su.kind == tykind.TY_NAMED) { su = su.under; };
+					su = tichase(su);
 					if (su != nil) {
 						if (typeeq(su.sub, want)) { return idx; };
 					};
@@ -19140,11 +19124,11 @@ fn flatslicevariantidx(c: *cgen, tagged: *node, elem: *node) i32 = {
 // (cmd/w6c/cgen.c:1177) over su->params + cg_tag_for_variant (:503).
 fn cgwidentagremap(c: *cgen, du: *tinfo, su: *tinfo, slot_off: i32) void = {
 	let dt: *tinfo = du;
-	for (dt != nil && dt.kind == tykind.TY_NAMED) { dt = dt.under; };
+	dt = tichase(dt);
 	if (dt == nil) { return; };
 	if (dt.kind != tykind.TY_TAGGED) { return; };
 	let st: *tinfo = su;
-	for (st != nil && st.kind == tykind.TY_NAMED) { st = st.under; };
+	st = tichase(st);
 	if (st == nil) { return; };
 	if (st.kind != tykind.TY_TAGGED) { return; };
 	let identity: bool = true;
@@ -19316,7 +19300,7 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 	if (e == nil) { return false; };
 	if (e.kind == nkind.N_UN && e.op == tkind.TK_STAR) {
 		let du: *tinfo = e.type_: *tinfo;
-		for (du != nil && du.kind == tykind.TY_NAMED) { du = du.under; };
+		du = tichase(du);
 		if (du == nil) { return false; };
 		if (du.kind != tykind.TY_TAGGED) { return false; };
 		if (du.nullable != 0) { return false; };
@@ -19324,7 +19308,7 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 	};
 	if (e.kind != nkind.N_INDEX && e.kind != nkind.N_DOT) { return false; };
 	let u: *tinfo = e.type_: *tinfo;
-	for (u != nil && u.kind == tykind.TY_NAMED) { u = u.under; };
+	u = tichase(u);
 	if (u == nil) { return false; };
 	if (u.kind != tykind.TY_TAGGED) { return false; };
 	return u.size: i32 > TUPLE_GPCAP * 8;
@@ -19341,12 +19325,12 @@ fn taggedmemread(c: *cgen, e: *node) bool = {
 fn taggedcastpeel(c: *cgen, e: *node) *node = {
 	for (e != nil && e.kind == nkind.N_CAST && e.lhs != nil) {
 		let cu: *tinfo = e.type_: *tinfo;
-		for (cu != nil && cu.kind == tykind.TY_NAMED) { cu = cu.under; };
+		cu = tichase(cu);
 		if (cu == nil) { return e; };
 		if (cu.kind != tykind.TY_TAGGED) { return e; };
 		if (cu.nullable != 0) { return e; };
 		let iu: *tinfo = e.lhs.type_: *tinfo;
-		for (iu != nil && iu.kind == tykind.TY_NAMED) { iu = iu.under; };
+		iu = tichase(iu);
 		if (iu == nil) { return e; };
 		if (iu.kind != tykind.TY_TAGGED) { return e; };
 		if (iu.nullable != 0) { return e; };
@@ -19365,7 +19349,7 @@ fn taggedidcastpeel(c: *cgen, e: *node) *node = {
 	for (e != nil && e.kind == nkind.N_CAST && e.lhs != nil) {
 		if (!typeeq(e.type_: *tinfo, e.lhs.type_: *tinfo)) { return e; };
 		let cu: *tinfo = e.type_: *tinfo;
-		for (cu != nil && cu.kind == tykind.TY_NAMED) { cu = cu.under; };
+		cu = tichase(cu);
 		if (cu == nil) { return e; };
 		if (cu.kind != tykind.TY_TAGGED) { return e; };
 		e = e.lhs;
@@ -20315,16 +20299,12 @@ export fn dotchainresolve(c: *cgen, n: *node,
     // (plus one TY_PTR hop for a `*struct` root). tfield.type_ then
     // supplies each nested struct directly, so no name re-lookup.
     let curstruct: *tinfo = cur.type_: *tinfo;
-    for (curstruct != nil && curstruct.kind == tykind.TY_NAMED) {
-        curstruct = curstruct.under;
-    };
+    curstruct = tichase(curstruct);
     if (*outptrroot) {
         if (curstruct == nil) { return false; };
         if (curstruct.kind != tykind.TY_PTR) { return false; };
         curstruct = curstruct.sub;
-        for (curstruct != nil && curstruct.kind == tykind.TY_NAMED) {
-            curstruct = curstruct.under;
-        };
+        curstruct = tichase(curstruct);
     };
     let i: i32 = nsteps - 1;
     for (i >= 0) {
@@ -20346,7 +20326,7 @@ export fn dotchainresolve(c: *cgen, n: *node,
             return true;
         };
         let ft: *tinfo = found.type_;
-        for (ft != nil && ft.kind == tykind.TY_NAMED) { ft = ft.under; };
+        ft = tichase(ft);
         if (ft == nil) { return false; };
         if (ft.kind == tykind.TY_STR) {
             // str IS []u8: .cap is the third header word, same as
@@ -20891,9 +20871,7 @@ fn cgstructlitfill(c: *cgen, si: *structinfo, lit: *node,
                         let agsz49: i32 = 0;
                         if (fi.tnode != nil) {
                             let agti49: *tinfo = fi.tnode.type_: *tinfo;
-                            for (agti49 != nil && agti49.kind == tykind.TY_NAMED) {
-                                agti49 = agti49.under;
-                            };
+                            agti49 = tichase(agti49);
                             if (agti49 != nil) { agsz49 = agti49.size: i32; };
                         };
                         aggcopy(c, agsz49);