Use main_func_info rather than bespoke logic in AOT

This moves from using the bespoke AOT UpdateMainWorkspaceSize to the
LoweredModule main_func_info property to unify with Graph executor
codegen.

Author: Mousius

src/relay/backend/aot_executor_codegen.cc

@@ -363,40 +363,6 @@ class AOTExecutorCodegen : public ExprVisitor {
     return ss.str();
   }
 
-  /*!
-   * \brief Update the "main" control function's metadata
-   *
-   * \param func The main function that contains calls to operator tir primitive functions
-   */
-  void UpdateMainWorkspaceSize(const tir::PrimFunc& primfunc, const relay::Function& func) {
-    auto workspace_byte_alignment = target_host_->GetAttr<Integer>("workspace-byte-alignment")
-                                        .value_or(tvm::runtime::kDefaultWorkspaceAlignment);
-    Integer workspace_size = CalculateWorkspaceBytes(primfunc, workspace_byte_alignment);
-    // Populate FunctionInfo
-    auto fi_node = make_object<FunctionInfoNode>();
-    // Initialize all target workspaces to zero
-    for (const auto& kv : targets_) {
-      auto tgt = kv.second;
-      fi_node->workspace_sizes.Set(tgt, 0);
-    }
-    fi_node->workspace_sizes.Set(target_host_, workspace_size);
-    fi_node->relay_primfuncs.Set(target_host_, func);
-
-    int64_t io_size = 0;
-    for (const auto& input : input_vars_) {
-      io_size += CalculateRelayExprSizeBytes(input->checked_type());
-    }
-    io_size += CalculateRelayExprSizeBytes(func->body->checked_type());
-    fi_node->io_sizes.Set(target_host_, io_size);
-
-    int64_t const_size = 0;
-    for (const auto& kv : params_by_expr_) {
-      const_size += CalculateRelayExprSizeBytes(kv.first->checked_type());
-    }
-    fi_node->constant_sizes.Set(target_host_, const_size);
-    function_metadata_.Set(String(runtime::symbol::tvm_module_main), FunctionInfo(fi_node));
-  }
-
   void VisitExpr_(const CallNode* op) override {
     // Descend the call tree
     for (auto arg : op->args) {
@@ -635,6 +601,7 @@ class AOTExecutorCodegen : public ExprVisitor {
           tec::UpdateFunctionMetadata(func, this->function_metadata_);
         });
 
+    function_metadata_.Set(runtime::symbol::tvm_module_main, lowered_module.main_func_info);
     auto lowered_main = lowered_module.main_module->Lookup("main");
     auto lowered_main_func = GetRef<Function>(lowered_main.as<FunctionNode>());
 
@@ -670,8 +637,6 @@ class AOTExecutorCodegen : public ExprVisitor {
     // because the packed calls arguments are not wrapped in TVMValues. To make this happen we need
     // to run the LegalizePackedCalls pass.
     auto prim_func = CreateMainFunc(mod_name, lowered_main_func->params.size());
-    UpdateMainWorkspaceSize(prim_func, lowered_main_func);
-
     LoweredOutput ret;
 
     ret.params = std::unordered_map<std::string, std::pair<int, const tvm::runtime::NDArray>>();