Add transform::Renamer

Renames symbols.
Currently only supports renaming to a symbol with a monotonic increasing suffix.

Change-Id: I7ae67a7b1740ac0e83c1821643cf7b8b1959f84d
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/42842
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: James Price <jrprice@google.com>

BUILD.gn

@@ -411,6 +411,8 @@ source_set("libtint_core_src") {
     "src/transform/first_index_offset.h",
     "src/transform/manager.cc",
     "src/transform/manager.h",
+    "src/transform/renamer.cc",
+    "src/transform/renamer.h",
     "src/transform/transform.cc",
     "src/transform/transform.h",
     "src/transform/vertex_pulling.cc",
@@ -852,6 +854,7 @@ source_set("tint_unittests_core_src") {
     "src/transform/bound_array_accessors_test.cc",
     "src/transform/emit_vertex_point_size_test.cc",
     "src/transform/first_index_offset_test.cc",
+    "src/transform/renamer_test.cc",
     "src/transform/test_helper.h",
     "src/transform/vertex_pulling_test.cc",
     "src/type/access_control_type_test.cc",

include/tint/tint.h

@@ -28,6 +28,7 @@
 #include "src/transform/emit_vertex_point_size.h"
 #include "src/transform/first_index_offset.h"
 #include "src/transform/manager.h"
+#include "src/transform/renamer.h"
 #include "src/transform/vertex_pulling.h"
 #include "src/type/type_manager.h"
 #include "src/validator/validator.h"

src/CMakeLists.txt

@@ -225,6 +225,8 @@ set(TINT_LIB_SRCS
   transform/first_index_offset.h
   transform/manager.cc
   transform/manager.h
+  transform/renamer.cc
+  transform/renamer.h
   transform/transform.cc
   transform/transform.h
   transform/vertex_pulling.cc
@@ -711,6 +713,7 @@ if(${TINT_BUILD_TESTS})
       transform/bound_array_accessors_test.cc
       transform/emit_vertex_point_size_test.cc
       transform/first_index_offset_test.cc
+      transform/renamer_test.cc
       transform/test_helper.h
       transform/vertex_pulling_test.cc
     )

src/transform/renamer.cc

@@ -0,0 +1,62 @@
+// Copyright 2021 The Tint 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.
+
+#include "src/transform/renamer.h"
+
+#include <memory>
+#include <utility>
+
+#include "src/program_builder.h"
+
+TINT_INSTANTIATE_TYPEINFO(tint::transform::Renamer::Data);
+
+namespace tint {
+namespace transform {
+
+Renamer::Data::Data(Remappings&& r) : remappings(std::move(r)) {}
+
+Renamer::Data::Data(const Data&) = default;
+
+Renamer::Data::~Data() = default;
+
+Renamer::Renamer() : cfg_{} {}
+
+Renamer::Renamer(const Config& config) : cfg_(config) {}
+
+Renamer::~Renamer() = default;
+
+Transform::Output Renamer::Run(const Program* in) {
+  ProgramBuilder out;
+  CloneContext ctx(&out, in);
+
+  Data::Remappings remappings;
+
+  switch (cfg_.method) {
+    case Method::kMonotonic:
+      ctx.ReplaceAll([&](Symbol sym) {
+        auto str_in = in->Symbols().NameFor(sym);
+        auto str_out = "_tint_" + std::to_string(sym.value());
+        remappings.emplace(str_in, str_out);
+        return out.Symbols().Register(str_out);
+      });
+      break;
+  }
+  ctx.Clone();
+
+  return Output(Program(std::move(out)),
+                std::make_unique<Data>(std::move(remappings)));
+}
+
+}  // namespace transform
+}  // namespace tint

src/transform/renamer.h

@@ -0,0 +1,83 @@
+// Copyright 2021 The Tint 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.
+
+#ifndef SRC_TRANSFORM_RENAMER_H_
+#define SRC_TRANSFORM_RENAMER_H_
+
+#include <string>
+#include <unordered_map>
+
+#include "src/transform/transform.h"
+
+namespace tint {
+namespace transform {
+
+/// Renamer is a Transform that renames all the symbols in a program.
+class Renamer : public Transform {
+ public:
+  /// Data holds information about shader usage and constant buffer offsets.
+  struct Data : public Castable<Data, transform::Data> {
+    /// Remappings is a map of old symbol name to new symbol name
+    using Remappings = std::unordered_map<std::string, std::string>;
+
+    /// Constructor
+    /// @param remappings the symbol remappings
+    explicit Data(Remappings&& remappings);
+
+    /// Copy constructor
+    Data(const Data&);
+
+    /// Destructor
+    ~Data() override;
+
+    /// A map of old symbol name to new symbol name
+    Remappings const remappings;
+  };
+
+  /// Method is an enumerator of renaming methods that can be used
+  enum class Method {
+    /// Every symbol will be replaced with an identifier containing a
+    /// monotonically incrementing integer.
+    kMonotonic,
+  };
+
+  /// Configuration options for the transform
+  struct Config {
+    /// The method used for renaming symbols
+    Method method = Method::kMonotonic;
+  };
+
+  /// Constructor using a default configuration
+  Renamer();
+
+  /// Constructor
+  /// @param config the configuration for the transform
+  explicit Renamer(const Config& config);
+
+  /// Destructor
+  ~Renamer() override;
+
+  /// Runs the transform on `program`, returning the transformation result.
+  /// @param program the source program to transform
+  /// @returns the transformation result
+  Output Run(const Program* program) override;
+
+ private:
+  Config const cfg_;
+};
+
+}  // namespace transform
+}  // namespace tint
+
+#endif  // SRC_TRANSFORM_RENAMER_H_

src/transform/renamer_test.cc

@@ -0,0 +1,85 @@
+// Copyright 2021 The Tint 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.
+
+#include "src/transform/renamer.h"
+
+#include "gmock/gmock.h"
+#include "src/transform/test_helper.h"
+
+namespace tint {
+namespace transform {
+namespace {
+
+using ::testing::ContainerEq;
+
+using RenamerTest = TransformTest;
+
+TEST_F(RenamerTest, EmptyModule) {
+  auto* src = "";
+  auto* expect = "";
+
+  auto got = Transform<Renamer>(src);
+
+  EXPECT_EQ(expect, str(got));
+
+  auto* data = got.data.Get<Renamer::Data>();
+
+  ASSERT_EQ(data->remappings.size(), 0u);
+}
+
+TEST_F(RenamerTest, BasicModuleVertexIndex) {
+  auto* src = R"(
+[[builtin(vertex_index)]] var<in> vert_idx : u32;
+
+fn test() -> u32 {
+  return vert_idx;
+}
+
+[[stage(vertex)]]
+fn entry() -> void {
+  test();
+}
+)";
+
+  auto* expect = R"(
+[[builtin(vertex_index)]] var<in> _tint_1 : u32;
+
+fn _tint_2() -> u32 {
+  return _tint_1;
+}
+
+[[stage(vertex)]]
+fn _tint_3() -> void {
+  _tint_2();
+}
+)";
+
+  auto got = Transform<Renamer>(src);
+
+  EXPECT_EQ(expect, str(got));
+
+  auto* data = got.data.Get<Renamer::Data>();
+
+  ASSERT_NE(data, nullptr);
+  Renamer::Data::Remappings expected_remappings = {
+      {"vert_idx", "_tint_1"},
+      {"test", "_tint_2"},
+      {"entry", "_tint_3"},
+  };
+  EXPECT_THAT(data->remappings, ContainerEq(expected_remappings));
+}
+
+}  // namespace
+}  // namespace transform
+}  // namespace tint