cmd/gc, runtime: rename writebarrierfat to typedmemmove

Preparation for replacing many memmove calls in runtime
with typedmemmove, which is a clearer description of what
the routine is doing.

For the same reason, rename writebarriercopy to typedslicecopy.

Change-Id: I6f23bef2c2215509fefba175b16908f76dc7538c
Reviewed-on: https://go-review.googlesource.com/2276
Reviewed-by: Rick Hudson <rlh@golang.org>

src/cmd/gc/builtin.c

@@ -113,8 +113,8 @@ char *runtimeimport =
 	"func @\"\".writebarrierfat1101 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
 	"func @\"\".writebarrierfat1110 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
 	"func @\"\".writebarrierfat1111 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
-	"func @\"\".writebarrierfat (@\"\".typ·1 *byte, @\"\".dst·2 *any, @\"\".src·3 *any)\n"
-	"func @\"\".writebarriercopy (@\"\".typ·2 *byte, @\"\".dst·3 any, @\"\".src·4 any) (? int)\n"
+	"func @\"\".typedmemmove (@\"\".typ·1 *byte, @\"\".dst·2 *any, @\"\".src·3 *any)\n"
+	"func @\"\".typedslicecopy (@\"\".typ·2 *byte, @\"\".dst·3 any, @\"\".src·4 any) (? int)\n"
 	"func @\"\".selectnbsend (@\"\".chanType·2 *byte, @\"\".hchan·3 chan<- any, @\"\".elem·4 *any) (? bool)\n"
 	"func @\"\".selectnbrecv (@\"\".chanType·2 *byte, @\"\".elem·3 *any, @\"\".hchan·4 <-chan any) (? bool)\n"
 	"func @\"\".selectnbrecv2 (@\"\".chanType·2 *byte, @\"\".elem·3 *any, @\"\".received·4 *bool, @\"\".hchan·5 <-chan any) (? bool)\n"

src/cmd/gc/runtime.go

@@ -144,8 +144,8 @@ func writebarrierfat1101(dst *any, _ *byte, src any)
 func writebarrierfat1110(dst *any, _ *byte, src any)
 func writebarrierfat1111(dst *any, _ *byte, src any)
 
-func writebarrierfat(typ *byte, dst *any, src *any)
-func writebarriercopy(typ *byte, dst any, src any) int
+func typedmemmove(typ *byte, dst *any, src *any)
+func typedslicecopy(typ *byte, dst any, src any) int
 
 func selectnbsend(chanType *byte, hchan chan<- any, elem *any) bool
 func selectnbrecv(chanType *byte, elem *any, hchan <-chan any) bool

src/cmd/gc/walk.c

@@ -2096,8 +2096,8 @@ applywritebarrier(Node *n, NodeList **init)
 				r = r->left;
 			r = nod(OADDR, r, N);
 			r->etype = 1; // addr does not escape
-			//warnl(n->lineno, "writebarrierfat %T %N", t, r);
-			n = mkcall1(writebarrierfn("writebarrierfat", t, r->left->type), T, init,
+			//warnl(n->lineno, "typedmemmove %T %N", t, r);
+			n = mkcall1(writebarrierfn("typedmemmove", t, r->left->type), T, init,
 				typename(t), l, r);
 		}
 	}
@@ -2952,7 +2952,7 @@ copyany(Node *n, NodeList **init, int runtimecall)
 	NodeList *l;
 
 	if(haspointers(n->left->type->type)) {
-		fn = writebarrierfn("writebarriercopy", n->left->type, n->right->type);
+		fn = writebarrierfn("typedslicecopy", n->left->type, n->right->type);
 		return mkcall1(fn, n->type, init, typename(n->left->type->type), n->left, n->right);
 	}
 

src/runtime/mgc0.go

@@ -288,8 +288,8 @@ func writebarrieriface(dst *[2]uintptr, src [2]uintptr) {
 // The implementations are written to wbfat.go.
 
 //go:nosplit
-func writebarrierfat(typ *_type, dst, src unsafe.Pointer) {
-	if !needwb() {
+func typedmemmove(typ *_type, dst, src unsafe.Pointer) {
+	if !needwb() || (typ.kind&kindNoPointers) != 0 {
 		memmove(dst, src, typ.size)
 		return
 	}
@@ -322,7 +322,7 @@ func writebarrierfat(typ *_type, dst, src unsafe.Pointer) {
 }
 
 //go:nosplit
-func writebarriercopy(typ *_type, dst, src slice) int {
+func typedslicecopy(typ *_type, dst, src slice) int {
 	n := dst.len
 	if n > src.len {
 		n = src.len
@@ -347,7 +347,7 @@ func writebarriercopy(typ *_type, dst, src slice) int {
 			srcp = add(srcp, uintptr(n-1)*typ.size)
 			i := uint(0)
 			for {
-				writebarrierfat(typ, dstp, srcp)
+				typedmemmove(typ, dstp, srcp)
 				if i++; i >= n {
 					break
 				}
@@ -359,7 +359,7 @@ func writebarriercopy(typ *_type, dst, src slice) int {
 			// out of the array they point into.
 			i := uint(0)
 			for {
-				writebarrierfat(typ, dstp, srcp)
+				typedmemmove(typ, dstp, srcp)
 				if i++; i >= n {
 					break
 				}

src/runtime/slice.go

@@ -88,7 +88,7 @@ func growslice(t *slicetype, old sliceStruct, n int64) sliceStruct {
 		// TODO(rsc): Use memmove when !needwb().
 		p = newarray(et, uintptr(newcap))
 		for i := 0; i < old.len; i++ {
-			writebarrierfat(et, add(p, uintptr(i)*et.size), add(old.array, uintptr(i)*et.size))
+			typedmemmove(et, add(p, uintptr(i)*et.size), add(old.array, uintptr(i)*et.size))
 		}
 	}