[PASS] Shape lowering (#16)

* [PASS] Shape lowering.

* Update to IRModule based.

* TIR function generation.

* Improve.

* Improve.

* Improve test.

* Improve.

* Address comment.

include/tvm/relax/expr_functor.h

@@ -208,22 +208,22 @@ class ExprMutator : public ExprFunctor<Expr(const Expr&)> {
    * visitor for types which transform them appropriately.
    */
   virtual Type VisitType(const Type& t);
-  virtual void VisitBinding(const Binding& binding);
-  virtual Var VisitVarBinding(const VarBinding& binding, IRBuilder& ir_builder);
-  virtual void VisitMatchShape(const MatchShape& binding, IRBuilder& ir_builder);
+  virtual void VisitBinding(const Binding& binding, IRBuilder& builder);
+  virtual Var VisitVarBinding(const VarBinding& binding, IRBuilder& builder);
+  virtual void VisitMatchShape(const MatchShape& binding, IRBuilder& builder);
   virtual BindingBlock VisitBindingBlock(const BindingBlock& block);
   virtual BindingBlock VisitDataflowBlock(const DataflowBlock& block);
 
  protected:
-  LazyIRBuilder irbuilder_;
+  IRBuilder builder_;
 };
 
 /*! \brief Dataflow Graph Rewriting for Custom Rewriting Passes
  */
 class DataflowMutator : public ExprMutator {
  public:
   virtual BindingBlock VisitDataflowBlock(const DataflowBlock& block);
-  virtual Var VisitVarBinding(const VarBinding& binding, IRBuilder& ir_builder);
+  virtual Var VisitVarBinding(const VarBinding& binding, IRBuilder& builder);
 
  protected:
   /*! \brief Look up the value binded to a var. */

python/tvm/relax/transform/transform.py

@@ -16,6 +16,7 @@
 # under the License.
 # pylint: disable=no-else-return
 # pylint: disable=unidiomatic-typecheck
+from tvm import IRModule 
 from . import _ffi_api
 
 def fma_rewrite(expr):
@@ -37,3 +38,13 @@ def explicit_memory_rewrite(expr):
         The input expression.
     """
     return _ffi_api.explicit_memory_rewrite(expr)
+
+def shape_lower(mod: IRModule) -> IRModule:
+    """Lower the shape expression in relax to shape heap and TIR functions.
+
+    Parameters
+    ----------
+    expr : tvm.IRModule
+        The input module.
+    """
+    return _ffi_api.shape_lower(mod)

src/relax/ir/expr_functor.cc

@@ -140,6 +140,9 @@ void ExprVisitor::VisitVarBinding(const VarBinding& binding) {
 
 void ExprVisitor::VisitMatchShape(const MatchShape& binding) {
   this->VisitExpr(binding->value);
+  // TODO(ziheng): should we change pattern from
+  // Array<PrimExpr> to ShapeExpr?
+  this->VisitExpr(ShapeExpr(binding->pattern));
 }
 
 void ExprVisitor::VisitBindingBlock(const BindingBlock& block) {
@@ -321,50 +324,53 @@ Expr ExprMutator::VisitExpr_(const SeqExprNode* op) {
 
 Type ExprMutator::VisitType(const Type& t) { return t; }
 
-void ExprMutator::VisitBinding(const Binding& binding) {
+void ExprMutator::VisitBinding(const Binding& binding, IRBuilder& builder) {
   Binding new_binding;
   if (binding.as<VarBindingNode>()) {
-    this->VisitVarBinding(Downcast<VarBinding>(binding), this->irbuilder_);
+    this->VisitVarBinding(Downcast<VarBinding>(binding), builder);
   } else if (binding.as<MatchShapeNode>()) {
-    this->VisitMatchShape(Downcast<MatchShape>(binding), this->irbuilder_);
+    this->VisitMatchShape(Downcast<MatchShape>(binding), builder);
   } else {
     LOG(FATAL) << "Wrong type.";
   }
 }
 
-Var ExprMutator::VisitVarBinding(const VarBinding& binding, IRBuilder& ir_builder) {
+Var ExprMutator::VisitVarBinding(const VarBinding& binding, IRBuilder& builder) {
   Expr new_value = this->Mutate(binding->value);
   if (!binding->var.as<DataflowVarNode>()) {
-    return ir_builder->EmitOutput(new_value);
+    return builder->EmitOutput(new_value);
   } else {
-    return ir_builder->Emit(Downcast<Call>(new_value));
+    return builder->Emit(Downcast<Call>(new_value));
   }
 }
 
-void ExprMutator::VisitMatchShape(const MatchShape& binding, IRBuilder& ir_builder) {
+void ExprMutator::VisitMatchShape(const MatchShape& binding, IRBuilder& builder) {
   this->Mutate(binding->value);
+  this->Mutate(ShapeExpr(binding->pattern));
 }
 
 BindingBlock ExprMutator::VisitBindingBlock(const BindingBlock& block) {
   if (block.as<DataflowBlockNode>()) {
     return this->VisitDataflowBlock(Downcast<DataflowBlock>(block));
   } else{
-    // TODO
-    return block;
+    this->builder_ = IRBuilderNode::Create();
+    for (auto binding : block->bindings) {
+      this->VisitBinding(binding, this->builder_);
+    }
+    auto blocks = this->builder_->GetBlocks();
+    return blocks.back();
   }
 }
 
 BindingBlock ExprMutator::VisitDataflowBlock(const DataflowBlock& block) {
-  this->irbuilder_ = LazyIRBuilderNode::Create(block);
+  this->builder_ = LazyIRBuilderNode::Create(block);
   {
-    With<DataflowScope> scope(this->irbuilder_);
+    With<DataflowScope> scope(this->builder_);
     for (auto binding : block->bindings) {
-      if (binding.as<VarBindingNode>()) {
-        this->VisitVarBinding(Downcast<VarBinding>(binding), this->irbuilder_);
-      }
+      this->VisitBinding(binding, this->builder_);
     }
   }
-  return this->irbuilder_->GetBlocks().back();
+  return this->builder_->GetBlocks().back();
 }
 
 Expr ExprMutator::VisitExpr(const Expr& expr) {
@@ -377,27 +383,27 @@ Expr ExprMutator::VisitExpr(const Expr& expr) {
 // DataflowMutator
 
 BindingBlock DataflowMutator::VisitDataflowBlock(const DataflowBlock& block) {
-  this->irbuilder_ = LazyIRBuilderNode::Create(block);
+  this->builder_ = LazyIRBuilderNode::Create(block);
   {
-    With<DataflowScope> scope(this->irbuilder_);
+    With<DataflowScope> scope(this->builder_);
     for (auto binding : block->bindings) {
       if (auto* var_binding = binding.as<VarBindingNode>()) {
-        Var var = this->VisitVarBinding(Downcast<VarBinding>(binding), this->irbuilder_);
+        Var var = this->VisitVarBinding(Downcast<VarBinding>(binding), this->builder_);
         this->pre_post_var_map_[var_binding->var] = var;
       }
     }
   }
-  return this->irbuilder_->GetBlocks().back();
+  return this->builder_->GetBlocks().back();
 }
 
-Var DataflowMutator::VisitVarBinding(const VarBinding& binding, IRBuilder& ir_builder) {
+Var DataflowMutator::VisitVarBinding(const VarBinding& binding, IRBuilder& builder) {
   Expr new_value = this->Mutate(binding->value);
   Var new_var;
   if (new_value.as<CallNode>()) {
-    new_var = ir_builder->Emit(Downcast<Call>(new_value));
+    new_var = builder->Emit(Downcast<Call>(new_value));
   }
   if (!binding->var.as<DataflowVarNode>()) {
-    new_var = ir_builder->EmitOutput(new_value);
+    new_var = builder->EmitOutput(new_value);
   }
   pre_post_var_map_[binding->var] = new_var;
   return new_var;
@@ -406,9 +412,9 @@ Var DataflowMutator::VisitVarBinding(const VarBinding& binding, IRBuilder& ir_bu
 Expr DataflowMutator::LookupVar(Var var) {
   auto it = pre_post_var_map_.find(var);
   if (it != pre_post_var_map_.end()) {
-    return irbuilder_->LookupVar(it->first);
+    return builder_->LookupVar(it->first);
   } else {
-    return irbuilder_->LookupVar(var);
+    return builder_->LookupVar(var);
   }
 }
 }  // namespace relax

src/relax/ir/ir_builder.cc

@@ -142,6 +142,7 @@ Var IRBuilderNode::EmitMatchShape(const Expr& value, const Array<PrimExpr>& patt
 }
 
 Var IRBuilderNode::Emit(const VarBinding& binding) {
+  // FIXME(yuchen or ziheng): consider binding in normal block)
   if (!binding->var.as<DataflowVarNode>()) {
     return EmitOutput(binding->value);
   } else {
@@ -192,9 +193,14 @@ Expr IRBuilderNode::LookupVar(const Var& var) {
   return it->second;
 }
 
-Function IRBuilderNode::Get() { return this->func_.func; }
+Function IRBuilderNode::Get() {
+  return this->func_.func;
+}
 
-std::vector<BindingBlock> IRBuilderNode::GetBlocks() { return this->func_.binding_blocks; }
+std::vector<BindingBlock> IRBuilderNode::GetBlocks() {
+  this->BuildBlock();
+  return this->func_.binding_blocks;
+}
 
 bool IRBuilderNode::CanProveShapeEqual(const Expr& lhs, const Expr& rhs) {
   if (lhs == rhs) {

src/relax/op/op.cc

@@ -57,7 +57,8 @@ Expr MakeCallDPS(Expr shape, Expr func, Tuple args) {
   return Call(op, {shape, func, args}, {}, {});
 }
 
-TVM_REGISTER_GLOBAL("relax.op.call_dps").set_body_typed(MakeCallDPS);
+TVM_REGISTER_GLOBAL("relax.op.call_dps")
+.set_body_typed(MakeCallDPS);
 
 // shape_of