Add break-if support.

This CL adds support for `break-if` to Tint.

Bug: tint:1633, tint:1451
Change-Id: I30dfd62a3e09255624ff76ebe0cdd3a3c7cf9c5f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/106420
Auto-Submit: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: dan sinclair <dsinclair@google.com>

src/tint/sem/break_if_statement.cc

@@ -0,0 +1,34 @@
+// Copyright 2022 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/sem/break_if_statement.h"
+
+#include "src/tint/program_builder.h"
+
+TINT_INSTANTIATE_TYPEINFO(tint::sem::BreakIfStatement);
+
+namespace tint::sem {
+
+BreakIfStatement::BreakIfStatement(const ast::BreakIfStatement* declaration,
+                                   const CompoundStatement* parent,
+                                   const sem::Function* function)
+    : Base(declaration, parent, function) {}
+
+BreakIfStatement::~BreakIfStatement() = default;
+
+const ast::BreakIfStatement* BreakIfStatement::Declaration() const {
+    return static_cast<const ast::BreakIfStatement*>(Base::Declaration());
+}
+
+}  // namespace tint::sem

src/tint/sem/break_if_statement.h

@@ -0,0 +1,60 @@
+// Copyright 2022 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_SEM_BREAK_IF_STATEMENT_H_
+#define SRC_TINT_SEM_BREAK_IF_STATEMENT_H_
+
+#include "src/tint/sem/statement.h"
+
+// Forward declarations
+namespace tint::ast {
+class BreakIfStatement;
+}  // namespace tint::ast
+namespace tint::sem {
+class Expression;
+}  // namespace tint::sem
+
+namespace tint::sem {
+
+/// Holds semantic information about a break-if statement
+class BreakIfStatement final : public Castable<BreakIfStatement, CompoundStatement> {
+  public:
+    /// Constructor
+    /// @param declaration the AST node for this break-if statement
+    /// @param parent the owning statement
+    /// @param function the owning function
+    BreakIfStatement(const ast::BreakIfStatement* declaration,
+                     const CompoundStatement* parent,
+                     const sem::Function* function);
+
+    /// Destructor
+    ~BreakIfStatement() override;
+
+    /// @returns the AST node
+    const ast::BreakIfStatement* Declaration() const;
+
+    /// @returns the break-if-statement condition expression
+    const Expression* Condition() const { return condition_; }
+
+    /// Sets the break-if-statement condition expression
+    /// @param condition the break-if condition expression
+    void SetCondition(const Expression* condition) { condition_ = condition; }
+
+  private:
+    const Expression* condition_ = nullptr;
+};
+
+}  // namespace tint::sem
+
+#endif  // SRC_TINT_SEM_BREAK_IF_STATEMENT_H_