diff --git a/internal/runtime/map.go b/internal/runtime/map.go
index 886980fd..c71df18d 100644
--- a/internal/runtime/map.go
+++ b/internal/runtime/map.go
@@ -442,7 +442,7 @@ bucketloop:
 			if t.IndirectKey() {
 				k = *((*unsafe.Pointer)(k))
 			}
-			if mapKeyEqual(t, key, k) {
+			if t.Key.Equal(key, k) {
 				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.KeySize)+i*uintptr(t.ValueSize))
 				if t.IndirectElem() {
 					e = *((*unsafe.Pointer)(e))
@@ -503,7 +503,7 @@ bucketloop:
 			if t.IndirectKey() {
 				k = *((*unsafe.Pointer)(k))
 			}
-			if mapKeyEqual(t, key, k) {
+			if t.Key.Equal(key, k) {
 				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.KeySize)+i*uintptr(t.ValueSize))
 				if t.IndirectElem() {
 					e = *((*unsafe.Pointer)(e))
@@ -547,7 +547,7 @@ bucketloop:
 			if t.IndirectKey() {
 				k = *((*unsafe.Pointer)(k))
 			}
-			if mapKeyEqual(t, key, k) {
+			if t.Key.Equal(key, k) {
 				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.KeySize)+i*uintptr(t.ValueSize))
 				if t.IndirectElem() {
 					e = *((*unsafe.Pointer)(e))
@@ -635,7 +635,7 @@ bucketloop:
 			if t.IndirectKey() {
 				k = *((*unsafe.Pointer)(k))
 			}
-			if !mapKeyEqual(t, key, k) {
+			if !t.Key.Equal(key, k) {
 				continue
 			}
 			// already have a mapping for key. Update it.
@@ -747,7 +747,7 @@ search:
 			if t.IndirectKey() {
 				k2 = *((*unsafe.Pointer)(k2))
 			}
-			if !mapKeyEqual(t, key, k2) {
+			if !t.Key.Equal(key, k2) {
 				continue
 			}
 			// Only clear key if there are pointers in it.
@@ -935,7 +935,7 @@ next:
 			// through the oldbucket, skipping any keys that will go
 			// to the other new bucket (each oldbucket expands to two
 			// buckets during a grow).
-			if t.ReflexiveKey() || mapKeyEqual(t, k, k) {
+			if t.ReflexiveKey() || t.Key.Equal(k, k) {
 				// If the item in the oldbucket is not destined for
 				// the current new bucket in the iteration, skip it.
 				hash := t.Hasher(k, uintptr(h.hash0))
@@ -956,7 +956,7 @@ next:
 			}
 		}
 		if (b.tophash[offi] != evacuatedX && b.tophash[offi] != evacuatedY) ||
-			!(t.ReflexiveKey() || mapKeyEqual(t, k, k)) {
+			!(t.ReflexiveKey() || t.Key.Equal(k, k)) {
 			// This is the golden data, we can return it.
 			// OR
 			// key!=key, so the entry can't be deleted or updated, so we can just return it.
@@ -1214,7 +1214,7 @@ func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
 					// Compute hash to make our evacuation decision (whether we need
 					// to send this key/elem to bucket x or bucket y).
 					hash := t.Hasher(k2, uintptr(h.hash0))
-					if h.flags&iterator != 0 && !t.ReflexiveKey() && !mapKeyEqual(t, k2, k2) {
+					if h.flags&iterator != 0 && !t.ReflexiveKey() && !t.Key.Equal(k2, k2) {
 						// If key != key (NaNs), then the hash could be (and probably
 						// will be) entirely different from the old hash. Moreover,
 						// it isn't reproducible. Reproducibility is required in the
diff --git a/internal/runtime/z_face.go b/internal/runtime/z_face.go
index e4d328cd..827e388b 100644
--- a/internal/runtime/z_face.go
+++ b/internal/runtime/z_face.go
@@ -218,6 +218,11 @@ func Interface(pkgPath, name string, methods []Imethod) *InterfaceType {
 		PkgPath_: pkgPath,
 		Methods:  methods,
 	}
+	if len(methods) == 0 {
+		ret.Equal = nilinterequal
+	} else {
+		ret.Equal = interequal
+	}
 	return ret
 }
 
@@ -355,12 +360,6 @@ func Implements(T, V *abi.Type) bool {
 }
 
 func EfaceEqual(v, u eface) bool {
-	if v.Kind() == abi.Interface {
-		v = v.Elem()
-	}
-	if u.Kind() == abi.Interface {
-		u = u.Elem()
-	}
 	if v._type == nil || u._type == nil {
 		return v._type == u._type
 	}
@@ -370,52 +369,10 @@ func EfaceEqual(v, u eface) bool {
 	if isDirectIface(v._type) {
 		return v.data == u.data
 	}
-	switch v.Kind() {
-	case abi.Bool,
-		abi.Int, abi.Int8, abi.Int16, abi.Int32, abi.Int64,
-		abi.Uint, abi.Uint8, abi.Uint16, abi.Uint32, abi.Uint64, abi.Uintptr,
-		abi.Float32, abi.Float64:
-		return *(*uintptr)(v.data) == *(*uintptr)(u.data)
-	case abi.Complex64:
-		return *(*complex64)(v.data) == *(*complex64)(u.data)
-	case abi.Complex128:
-		return *(*complex128)(v.data) == *(*complex128)(u.data)
-	case abi.String:
-		return *(*string)(v.data) == *(*string)(u.data)
-	case abi.Pointer, abi.UnsafePointer:
-		return v.data == u.data
-	case abi.Array:
-		n := v._type.Len()
-		tt := v._type.ArrayType()
-		index := func(data unsafe.Pointer, i int) eface {
-			offset := i * int(tt.Elem.Size_)
-			return eface{tt.Elem, c.Advance(data, offset)}
-		}
-		for i := 0; i < n; i++ {
-			if !EfaceEqual(index(v.data, i), index(u.data, i)) {
-				return false
-			}
-		}
-		return true
-	case abi.Struct:
-		st := v._type.StructType()
-		field := func(data unsafe.Pointer, ft *abi.StructField) eface {
-			ptr := c.Advance(data, int(ft.Offset))
-			if isDirectIface(ft.Typ) {
-				ptr = *(*unsafe.Pointer)(ptr)
-			}
-			return eface{ft.Typ, ptr}
-		}
-		for _, ft := range st.Fields {
-			if !EfaceEqual(field(v.data, &ft), field(u.data, &ft)) {
-				return false
-			}
-		}
-		return true
-	case abi.Func, abi.Map, abi.Slice:
-		break
+	if equal := v._type.Equal; equal != nil {
+		return equal(v.data, u.data)
 	}
-	panic("not comparable")
+	panic(errorString("comparing uncomparable type " + v._type.String()).Error())
 }
 
 func (v eface) Kind() abi.Kind {
diff --git a/internal/runtime/z_map.go b/internal/runtime/z_map.go
index 2cb8e9ee..76fee872 100644
--- a/internal/runtime/z_map.go
+++ b/internal/runtime/z_map.go
@@ -82,29 +82,3 @@ func MapIterNext(it *hiter) (ok bool, k unsafe.Pointer, v unsafe.Pointer) {
 	mapiternext(it)
 	return
 }
-
-func mapKeyEqual(t *maptype, p, q unsafe.Pointer) bool {
-	if isDirectIface(t.Key) {
-		switch t.Key.Size_ {
-		case 0:
-			return true
-		case 1:
-			return memequal8(p, q)
-		case 2:
-			return memequal16(p, q)
-		case 4:
-			return memequal32(p, q)
-		case 8:
-			return memequal64(p, q)
-		}
-	}
-	switch t.Key.Kind() {
-	case abi.String:
-		return strequal(p, q)
-	case abi.Complex64:
-		return c64equal(p, q)
-	case abi.Complex128:
-		return c128equal(p, q)
-	}
-	return t.Key.Equal(p, q)
-}
diff --git a/internal/runtime/z_type.go b/internal/runtime/z_type.go
index 3caacb2a..684362d3 100644
--- a/internal/runtime/z_type.go
+++ b/internal/runtime/z_type.go
@@ -30,6 +30,36 @@ var (
 	tyBasic [abi.UnsafePointer + 1]*Type
 )
 
+func basicEqual(kind Kind, size uintptr) func(a, b unsafe.Pointer) bool {
+	switch kind {
+	case abi.Bool, abi.Int, abi.Int8, abi.Int16, abi.Int32, abi.Int64,
+		abi.Uint, abi.Uint8, abi.Uint16, abi.Uint32, abi.Uint64, abi.Uintptr:
+		switch size {
+		case 1:
+			return memequal8
+		case 2:
+			return memequal16
+		case 4:
+			return memequal32
+		case 8:
+			return memequal64
+		}
+	case abi.Float32:
+		return f32equal
+	case abi.Float64:
+		return f64equal
+	case abi.Complex64:
+		return c64equal
+	case abi.Complex128:
+		return c128equal
+	case abi.String:
+		return strequal
+	case abi.UnsafePointer:
+		return ptrequal
+	}
+	panic("unreachable")
+}
+
 func Basic(kind Kind) *Type {
 	if tyBasic[kind] == nil {
 		name, size, align := basicTypeInfo(kind)
@@ -39,10 +69,8 @@ func Basic(kind Kind) *Type {
 			Align_:      uint8(align),
 			FieldAlign_: uint8(align),
 			Kind_:       uint8(kind),
+			Equal:       basicEqual(kind, size),
 			Str_:        name,
-			Equal: func(a, b unsafe.Pointer) bool {
-				return uintptr(a) == uintptr(b)
-			},
 		}
 	}
 	return tyBasic[kind]
@@ -115,15 +143,33 @@ func Struct(pkgPath string, size uintptr, fields ...abi.StructField) *Type {
 		PkgPath_: pkgPath,
 		Fields:   fields,
 	}
+	var comparable bool = true
 	var typalign uint8
 	for _, f := range fields {
 		ft := f.Typ
 		if ft.Align_ > typalign {
 			typalign = ft.Align_
 		}
+		comparable = comparable && (ft.Equal != nil)
 	}
 	ret.Align_ = typalign
 	ret.FieldAlign_ = typalign
+	if comparable {
+		if size == 0 {
+			ret.Equal = memequal0
+		} else {
+			ret.Equal = func(p, q unsafe.Pointer) bool {
+				for _, ft := range fields {
+					pi := add(p, ft.Offset)
+					qi := add(q, ft.Offset)
+					if !ft.Typ.Equal(pi, qi) {
+						return false
+					}
+				}
+				return true
+			}
+		}
+	}
 	return &ret.Type
 }
 
@@ -149,6 +195,7 @@ func newPointer(elem *Type) *Type {
 			Align_:      pointerAlign,
 			FieldAlign_: pointerAlign,
 			Kind_:       uint8(abi.Pointer),
+			Equal:       ptrequal,
 		},
 		Elem: elem,
 	}
@@ -192,6 +239,22 @@ func ArrayOf(length uintptr, elem *Type) *Type {
 		Slice: SliceOf(elem),
 		Len:   length,
 	}
+	if eequal := elem.Equal; eequal != nil {
+		if elem.Size_ == 0 {
+			ret.Equal = memequal0
+		} else {
+			ret.Equal = func(p, q unsafe.Pointer) bool {
+				for i := uintptr(0); i < length; i++ {
+					pi := add(p, i*elem.Size_)
+					qi := add(q, i*elem.Size_)
+					if !eequal(pi, qi) {
+						return false
+					}
+				}
+				return true
+			}
+		}
+	}
 	return &ret.Type
 }