[Pass] Introduce flag to diable cp async lowering (#633)

* [Enhancement] Update PipelinePlanner to support async copy configuration

- Modified the `Substitute` method in `PipelinePlanner` to accept a `use_async_copy` parameter, allowing for more flexible pipeline planning based on async copy requirements.
- Updated the constructor of `PipelinePlanner` to initialize the `use_async_copy_` member variable.
- Adjusted the logic in the pipeline planning process to conditionally apply async copy annotations based on the new parameter.
- Commented out the `LoopVectorizeDynamic` call in `LowerAndLegalize` to prevent unintended modifications during the legalizing phase.

* Refactor PipelinePlanning function for improved readability

- Adjusted the formatting of the `use_async_copy` variable assignment in the `PipelinePlanning` function to enhance code clarity and maintainability.

src/transform/pipeline_planning.cc

@@ -165,8 +165,8 @@ private:
 
 class PipelinePlanner : public StmtExprMutator {
 public:
-  static Stmt Substitute(const PrimFunc &f) {
-    PipelinePlanner substituter;
+  static Stmt Substitute(const PrimFunc &f, bool use_async_copy = true) {
+    PipelinePlanner substituter(use_async_copy);
     for (const auto &[_, buffer] : f->buffer_map) {
       substituter.buffer_data_to_buffer_.Set(buffer->data, buffer);
     }
@@ -179,6 +179,7 @@ public:
 
 private:
   PipelinePlanner() = default;
+  PipelinePlanner(bool use_async_copy) : use_async_copy_(use_async_copy) {}
 
   /*! \brief Information about a pipeline stage
    *
@@ -262,7 +263,7 @@ private:
         }
       }
       annotations.Set(tir::attr::software_pipeline_stage, stage_anno);
-      if (TargetHasAsyncCopy(target_))
+      if (TargetHasAsyncCopy(target_) && use_async_copy_)
         annotations.Set(tir::attr::software_pipeline_async_stages,
                         Array<Integer>{0});
       auto for_node = GetRef<For>(loop);
@@ -459,7 +460,7 @@ private:
 
     annotations.Set(tir::attr::software_pipeline_stage, Array<Integer>(stages));
     annotations.Set(tir::attr::software_pipeline_order, Array<Integer>(orders));
-    if (TargetHasAsyncCopy(target_))
+    if (TargetHasAsyncCopy(target_) && use_async_copy_)
       annotations.Set(tir::attr::software_pipeline_async_stages,
                       Array<Integer>{0});
 
@@ -480,13 +481,16 @@ private:
 
   Map<Var, Buffer> buffer_data_to_buffer_;
   Target target_;
+  bool use_async_copy_;
 };
 
 tvm::transform::Pass PipelinePlanning() {
   using namespace tir::transform;
   auto pass_func = [=](PrimFunc f, IRModule m, PassContext ctx) {
+    bool use_async_copy =
+        ctx->GetConfig<Bool>("tir.use_async_copy", Bool(true)).value();
     PrimFuncNode *fptr = f.CopyOnWrite();
-    fptr->body = PipelinePlanner::Substitute(f);
+    fptr->body = PipelinePlanner::Substitute(f, use_async_copy);
     return f;
   };
   return CreatePrimFuncPass(pass_func, 0, "tl.PipelinePlanning", {});