diff --git a/internal/shader/block.go b/internal/shader/block.go
deleted file mode 100644
index 99263faaf..000000000
--- a/internal/shader/block.go
+++ /dev/null
@@ -1,45 +0,0 @@
-// Copyright 2020 The Ebiten Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package shader
-
-import (
-	"go/ast"
-	"go/token"
-)
-
-type block struct {
-	types  []typ
-	vars   []variable
-	consts []constant
-	funcs  []function
-	stmts  []stmt
-	pos    token.Pos
-	outer  *block
-}
-
-type stmtType int
-
-const (
-	stmtNone stmtType = iota
-	stmtAssign
-	stmtBlock
-	stmtReturn
-)
-
-type stmt struct {
-	stmtType stmtType
-	exprs    []ast.Expr
-	block    *block
-}
diff --git a/internal/shader/shader.go b/internal/shader/shader.go
index e8162b5f9..68fdf53c1 100644
--- a/internal/shader/shader.go
+++ b/internal/shader/shader.go
@@ -37,10 +37,12 @@ type constant struct {
 }
 
 type function struct {
-	name string
-	args []variable
-	rets []variable
-	body *block
+	name  string
+	args  []variable
+	rets  []variable
+	block *block
+
+	ir shaderir.Func
 }
 
 type compileState struct {
@@ -56,6 +58,15 @@ type compileState struct {
 	errs []string
 }
 
+type block struct {
+	types  []typ
+	vars   []variable
+	consts []constant
+	funcs  []function
+	pos    token.Pos
+	outer  *block
+}
+
 type ParseError struct {
 	errs []string
 }
@@ -232,7 +243,7 @@ func (cs *compileState) parseFunc(d *ast.FuncDecl, block *block) function {
 		name: d.Name.Name,
 		args: args,
 		rets: rets,
-		body: cs.parseBlock(block, d.Body),
+		//body: cs.parseBlock(block, d.Body),
 	}
 }
 
@@ -255,26 +266,26 @@ func (cs *compileState) parseBlock(outer *block, b *ast.BlockStmt) *block {
 					}
 					block.vars = append(block.vars, v)
 				}
-				for i := range l.Rhs {
-					block.stmts = append(block.stmts, stmt{
+				for range l.Rhs {
+					/*block.stmts = append(block.stmts, stmt{
 						stmtType: stmtAssign,
 						exprs:    []ast.Expr{l.Lhs[i], l.Rhs[i]},
-					})
+					})*/
 				}
 			case token.ASSIGN:
 				// TODO: What about the statement `a,b = b,a?`
-				for i := range l.Rhs {
-					block.stmts = append(block.stmts, stmt{
+				for range l.Rhs {
+					/*block.stmts = append(block.stmts, stmt{
 						stmtType: stmtAssign,
 						exprs:    []ast.Expr{l.Lhs[i], l.Rhs[i]},
-					})
+					})*/
 				}
 			}
 		case *ast.BlockStmt:
-			block.stmts = append(block.stmts, stmt{
+			/*block.stmts = append(block.stmts, stmt{
 				stmtType: stmtBlock,
 				block:    cs.parseBlock(block, l),
-			})
+			})*/
 		case *ast.DeclStmt:
 			cs.parseDecl(block, l.Decl, false)
 		case *ast.ReturnStmt:
@@ -282,10 +293,10 @@ func (cs *compileState) parseBlock(outer *block, b *ast.BlockStmt) *block {
 			for _, r := range l.Results {
 				exprs = append(exprs, r)
 			}
-			block.stmts = append(block.stmts, stmt{
+			/*block.stmts = append(block.stmts, stmt{
 				stmtType: stmtReturn,
 				exprs:    exprs,
-			})
+			})*/
 		}
 	}