[wasm][cleanup] Use getters in IndirectFunctionTableEntry::CopyFrom

This makes the code easier to read, and will also be helpful for the
extension to multiple indirect function tables.

R=clemensh@chromium.org

Bug: v8:9396
Change-Id: Idba143611e13f6b6cfc0e9d6c6f380ee3566db80
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1678476
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62390}

src/wasm/wasm-objects.cc

@@ -1506,26 +1506,21 @@ void IndirectFunctionTableEntry::Set(int sig_id, Address call_target,
   instance_->indirect_function_table_refs().set(index_, ref);
 }
 
-Object IndirectFunctionTableEntry::object_ref() {
+Object IndirectFunctionTableEntry::object_ref() const {
   return instance_->indirect_function_table_refs().get(index_);
 }
 
-int IndirectFunctionTableEntry::sig_id() {
+int IndirectFunctionTableEntry::sig_id() const {
   return instance_->indirect_function_table_sig_ids()[index_];
 }
 
-Address IndirectFunctionTableEntry::target() {
+Address IndirectFunctionTableEntry::target() const {
   return instance_->indirect_function_table_targets()[index_];
 }
 
 void IndirectFunctionTableEntry::CopyFrom(
     const IndirectFunctionTableEntry& that) {
-  instance_->indirect_function_table_sig_ids()[index_] =
-      that.instance_->indirect_function_table_sig_ids()[that.index_];
-  instance_->indirect_function_table_targets()[index_] =
-      that.instance_->indirect_function_table_targets()[that.index_];
-  instance_->indirect_function_table_refs().set(
-      index_, that.instance_->indirect_function_table_refs().get(that.index_));
+  Set(that.sig_id(), that.target(), that.object_ref());
 }
 
 void ImportedFunctionEntry::SetWasmToJs(

src/wasm/wasm-objects.h

@@ -71,9 +71,9 @@ class IndirectFunctionTableEntry {
 
   void CopyFrom(const IndirectFunctionTableEntry& that);
 
-  Object object_ref();
-  int sig_id();
-  Address target();
+  Object object_ref() const;
+  int sig_id() const;
+  Address target() const;
 
  private:
   Handle<WasmInstanceObject> const instance_;