[ir] Split AST and SEM sources out of core ir.

This CL moves the need to pull in SEM and AST into a specific
`libtint_ir_builder_src` library. This will make it a GN error if we
accidentally try to use the SEM or AST inside the IR after the initial
construction.

This required move the `ToProgram`/`FromProgram` methods out of
`ir::Module` and into an `ir::Converter` class.

Bug: tint:1921
Change-Id: I2e6ae195f9a100030b43f35a2c5dad634433147f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/129661
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>

src/tint/BUILD.gn

@@ -1104,6 +1104,24 @@ libtint_source_set("libtint_syntax_tree_writer_src") {
   ]
 }
 
+libtint_source_set("libtint_ir_builder_src") {
+  sources = [
+    "ir/builder_impl.cc",
+    "ir/builder_impl.h",
+    "ir/converter.cc",
+    "ir/converter.h",
+  ]
+  deps = [
+    ":libtint_ast_src",
+    ":libtint_constant_src",
+    ":libtint_ir_src",
+    ":libtint_program_src",
+    ":libtint_sem_src",
+    ":libtint_type_src",
+    ":libtint_utils_src",
+  ]
+}
+
 libtint_source_set("libtint_ir_src") {
   sources = [
     "ir/binary.cc",
@@ -1114,8 +1132,6 @@ libtint_source_set("libtint_ir_src") {
     "ir/block.h",
     "ir/builder.cc",
     "ir/builder.h",
-    "ir/builder_impl.cc",
-    "ir/builder_impl.h",
     "ir/builtin.cc",
     "ir/builtin.h",
     "ir/call.cc",
@@ -1161,11 +1177,8 @@ libtint_source_set("libtint_ir_src") {
   ]
 
   deps = [
-    ":libtint_ast_src",
     ":libtint_builtins_src",
     ":libtint_constant_src",
-    ":libtint_program_src",
-    ":libtint_sem_src",
     ":libtint_symbols_src",
     ":libtint_type_src",
     ":libtint_utils_src",
@@ -1222,7 +1235,10 @@ source_set("libtint") {
   if (tint_build_ir) {
     assert(!build_with_chromium,
            "tint_build_ir cannot be used when building Chromium")
-    public_deps += [ ":libtint_ir_src" ]
+    public_deps += [
+      ":libtint_ir_builder_src",
+      ":libtint_ir_src",
+    ]
   }
 
   configs += [ ":tint_common_config" ]
@@ -2112,7 +2128,10 @@ if (tint_build_unittests) {
       "ir/unary_test.cc",
     ]
 
-    deps = [ ":libtint_ir_src" ]
+    deps = [
+      ":libtint_ir_builder_src",
+      ":libtint_ir_src",
+    ]
   }
 
   if (build_with_chromium) {

src/tint/CMakeLists.txt

@@ -718,6 +718,8 @@ if(${TINT_BUILD_IR})
     ir/construct.h
     ir/convert.cc
     ir/convert.h
+    ir/converter.cc
+    ir/converter.h
     ir/debug.cc
     ir/debug.h
     ir/disassembler.cc

src/tint/cmd/loopy.cc

@@ -19,6 +19,7 @@
 #include "tint/tint.h"
 
 #if TINT_BUILD_IR
+#include "src/tint/ir/converter.h"
 #include "src/tint/ir/module.h"
 #endif  // TINT_BUILD_IR
 
@@ -377,7 +378,7 @@ int main(int argc, const char** argv) {
             loop_count = options.loop_count;
         }
         for (uint32_t i = 0; i < loop_count; ++i) {
-            auto result = tint::ir::Module::FromProgram(program.get());
+            auto result = tint::ir::Converter::FromProgram(program.get());
             if (!result) {
                 std::cerr << "Failed to build IR from program: " << result.Failure() << std::endl;
             }

src/tint/cmd/main.cc

@@ -49,9 +49,10 @@
 #include "tint/tint.h"
 
 #if TINT_BUILD_IR
-#include "src/tint/ir/debug.h"
-#include "src/tint/ir/disassembler.h"
-#include "src/tint/ir/module.h"
+#include "src/tint/ir/converter.h"     // nogncheck
+#include "src/tint/ir/debug.h"         // nogncheck
+#include "src/tint/ir/disassembler.h"  // nogncheck
+#include "src/tint/ir/module.h"        // nogncheck
 #endif                                 // TINT_BUILD_IR
 
 namespace {
@@ -1078,7 +1079,7 @@ int main(int argc, const char** argv) {
 
 #if TINT_BUILD_IR
     if (options.dump_ir || options.dump_ir_graph) {
-        auto result = tint::ir::Module::FromProgram(program.get());
+        auto result = tint::ir::Converter::FromProgram(program.get());
         if (!result) {
             std::cerr << "Failed to build IR from program: " << result.Failure() << std::endl;
         } else {

src/tint/ir/builder.cc

@@ -16,8 +16,6 @@
 
 #include <utility>
 
-#include "src/tint/ir/builder_impl.h"
-
 namespace tint::ir {
 
 Builder::Builder() {}

src/tint/ir/converter.cc

@@ -0,0 +1,42 @@
+// Copyright 2023 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/tint/ir/converter.h"
+
+#include "src/tint/ir/builder_impl.h"
+#include "src/tint/program.h"
+
+namespace tint::ir {
+
+// static
+Converter::Result Converter::FromProgram(const Program* program) {
+    if (!program->IsValid()) {
+        return Result{std::string("input program is not valid")};
+    }
+
+    BuilderImpl b(program);
+    auto r = b.Build();
+    if (!r) {
+        return b.Diagnostics().str();
+    }
+
+    return Result{r.Move()};
+}
+
+// static
+const Program* Converter::ToProgram() {
+    return nullptr;
+}
+
+}  // namespace tint::ir

src/tint/ir/converter.h

@@ -0,0 +1,54 @@
+// Copyright 2023 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_TINT_IR_CONVERTER_H_
+#define SRC_TINT_IR_CONVERTER_H_
+
+#include <string>
+
+#include "src/tint/ir/module.h"
+#include "src/tint/utils/result.h"
+
+// Forward Declarations
+namespace tint {
+class Program;
+}  // namespace tint
+
+namespace tint::ir {
+
+/// Class for converting into and out of IR.
+class Converter {
+  public:
+    /// The result type for the FromProgram method.
+    using Result = utils::Result<Module, std::string>;
+
+    /// Builds an ir::Module from the given Program
+    /// @param program the Program to use.
+    /// @returns the `utiils::Result` of generating the IR. The result will contain the `ir::Module`
+    /// on success, otherwise the `std::string` error.
+    ///
+    /// @note this assumes the program |IsValid|, and has had const-eval done so
+    /// any abstract values have been calculated and converted into the relevant
+    /// concrete types.
+    static Result FromProgram(const Program* program);
+
+    /// Converts the module back to a Program
+    /// @returns the resulting program, or nullptr on error
+    ///  (Note, this will probably turn into a utils::Result, just stubbing for now)
+    static const Program* ToProgram();
+};
+
+}  // namespace tint::ir
+
+#endif  // SRC_TINT_IR_CONVERTER_H_

src/tint/ir/module.cc

@@ -14,26 +14,8 @@
 
 #include "src/tint/ir/module.h"
 
-#include "src/tint/ir/builder_impl.h"
-#include "src/tint/program.h"
-
 namespace tint::ir {
 
-// static
-Module::Result Module::FromProgram(const Program* program) {
-    if (!program->IsValid()) {
-        return Result{std::string("input program is not valid")};
-    }
-
-    BuilderImpl b(program);
-    auto r = b.Build();
-    if (!r) {
-        return b.Diagnostics().str();
-    }
-
-    return Result{r.Move()};
-}
-
 Module::Module() = default;
 
 Module::Module(Module&&) = default;
@@ -42,8 +24,4 @@ Module::~Module() = default;
 
 Module& Module::operator=(Module&&) = default;
 
-const Program* Module::ToProgram() const {
-    return nullptr;
-}
-
 }  // namespace tint::ir

src/tint/ir/module.h

@@ -28,29 +28,11 @@
 #include "src/tint/utils/result.h"
 #include "src/tint/utils/vector.h"
 
-// Forward Declarations
-namespace tint {
-class Program;
-}  // namespace tint
-
 namespace tint::ir {
 
 /// Main module class for the IR.
 class Module {
   public:
-    /// The result type for the FromProgram method.
-    using Result = utils::Result<Module, std::string>;
-
-    /// Builds an ir::Module from the given Program
-    /// @param program the Program to use.
-    /// @returns the `utiils::Result` of generating the IR. The result will contain the `ir::Module`
-    /// on success, otherwise the `std::string` error.
-    ///
-    /// @note this assumes the program |IsValid|, and has had const-eval done so
-    /// any abstract values have been calculated and converted into the relevant
-    /// concrete types.
-    static Result FromProgram(const Program* program);
-
     /// Constructor
     Module();
     /// Move constructor
@@ -64,11 +46,6 @@ class Module {
     /// @returns a reference to this module
     Module& operator=(Module&& o);
 
-    /// Converts the module back to a Program
-    /// @returns the resulting program, or nullptr on error
-    ///  (Note, this will probably turn into a utils::Result, just stubbing for now)
-    const Program* ToProgram() const;
-
   private:
     /// Program Id required to create other components
     ProgramID prog_id_;