fix(slots): differentiate dynamic/static compiled slots

fix #1557

packages/compiler-core/src/transforms/vSlot.ts

@@ -135,7 +135,7 @@ export function buildSlots(
   let hasDynamicSlots = context.scopes.vSlot > 0 || context.scopes.vFor > 0
   // with `prefixIdentifiers: true`, this can be further optimized to make
   // it dynamic only when the slot actually uses the scope variables.
-  if (!__BROWSER__ && context.prefixIdentifiers) {
+  if (!__BROWSER__ && !context.ssr && context.prefixIdentifiers) {
     hasDynamicSlots = hasScopeRef(node, context.identifiers)
   }
 
@@ -144,6 +144,9 @@ export function buildSlots(
   const onComponentSlot = findDir(node, 'slot', true)
   if (onComponentSlot) {
     const { arg, exp } = onComponentSlot
+    if (arg && !isStaticExp(arg)) {
+      hasDynamicSlots = true
+    }
     slotsProperties.push(
       createObjectProperty(
         arg || createSimpleExpression('default', true),
@@ -317,7 +320,12 @@ export function buildSlots(
 
   let slots = createObjectExpression(
     slotsProperties.concat(
-      createObjectProperty(`_`, createSimpleExpression(`1`, false))
+      createObjectProperty(
+        `_`,
+        // 2 = compiled but dynamic = can skip normalization, but must run diff
+        // 1 = compiled and static = can skip normalization AND diff as optimized
+        createSimpleExpression(hasDynamicSlots ? `2` : `1`, false)
+      )
     ),
     loc
   ) as SlotsExpression