Emit switch statements.
This CL updates the WGSL generator to output switch statements.
Bug: tint:4
Change-Id: I4450b10932960691c76e76869105ade01fdd5a79
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/17282
Reviewed-by: David Neto <dneto@google.com>
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 1ed767f..e7ae9cf 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -424,6 +424,7 @@
writer/wgsl/generator_impl_regardless_test.cc
writer/wgsl/generator_impl_relational_test.cc
writer/wgsl/generator_impl_return_test.cc
+ writer/wgsl/generator_impl_switch_test.cc
writer/wgsl/generator_impl_type_test.cc
writer/wgsl/generator_impl_unary_derivative_test.cc
writer/wgsl/generator_impl_unary_method_test.cc
diff --git a/src/writer/wgsl/generator_impl.cc b/src/writer/wgsl/generator_impl.cc
index 21524c5..4ad4db9 100644
--- a/src/writer/wgsl/generator_impl.cc
+++ b/src/writer/wgsl/generator_impl.cc
@@ -44,6 +44,7 @@
#include "src/ast/struct.h"
#include "src/ast/struct_member.h"
#include "src/ast/struct_member_offset_decoration.h"
+#include "src/ast/switch_statement.h"
#include "src/ast/type/array_type.h"
#include "src/ast/type/matrix_type.h"
#include "src/ast/type/pointer_type.h"
@@ -679,6 +680,9 @@
if (stmt->IsReturn()) {
return EmitReturn(stmt->AsReturn());
}
+ if (stmt->IsSwitch()) {
+ return EmitSwitch(stmt->AsSwitch());
+ }
if (stmt->IsVariable()) {
return EmitVariable(stmt->AsVariable()->variable());
}
@@ -840,6 +844,30 @@
return true;
}
+bool GeneratorImpl::EmitSwitch(ast::SwitchStatement* stmt) {
+ make_indent();
+
+ out_ << "switch(";
+ if (!EmitExpression(stmt->condition())) {
+ return false;
+ }
+ out_ << ") {" << std::endl;
+
+ increment_indent();
+
+ for (const auto& s : stmt->body()) {
+ if (!EmitCase(s.get())) {
+ return false;
+ }
+ }
+
+ decrement_indent();
+ make_indent();
+ out_ << "}" << std::endl;
+
+ return true;
+}
+
bool GeneratorImpl::EmitUnless(ast::UnlessStatement* stmt) {
make_indent();
diff --git a/src/writer/wgsl/generator_impl.h b/src/writer/wgsl/generator_impl.h
index 5d9ad47..62425f8 100644
--- a/src/writer/wgsl/generator_impl.h
+++ b/src/writer/wgsl/generator_impl.h
@@ -162,6 +162,10 @@
/// @param stmt the statement to emit
/// @returns true if the statement was emitted
bool EmitStatement(ast::Statement* stmt);
+ /// Handles generating a switch statement
+ /// @param stmt the statement to emit
+ /// @returns true if the statement was emitted
+ bool EmitSwitch(ast::SwitchStatement* stmt);
/// Handles generating type
/// @param type the type to generate
/// @returns true if the type is emitted
diff --git a/src/writer/wgsl/generator_impl_switch_test.cc b/src/writer/wgsl/generator_impl_switch_test.cc
new file mode 100644
index 0000000..22f8f43
--- /dev/null
+++ b/src/writer/wgsl/generator_impl_switch_test.cc
@@ -0,0 +1,71 @@
+// Copyright 2020 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 <memory>
+#include <vector>
+
+#include "gtest/gtest.h"
+#include "src/ast/break_statement.h"
+#include "src/ast/case_statement.h"
+#include "src/ast/identifier_expression.h"
+#include "src/ast/int_literal.h"
+#include "src/ast/switch_statement.h"
+#include "src/writer/wgsl/generator_impl.h"
+
+namespace tint {
+namespace writer {
+namespace wgsl {
+namespace {
+
+using GeneratorImplTest = testing::Test;
+
+TEST_F(GeneratorImplTest, Emit_Switch) {
+ auto def = std::make_unique<ast::CaseStatement>();
+ std::vector<std::unique_ptr<ast::Statement>> def_body;
+ def_body.push_back(std::make_unique<ast::BreakStatement>());
+ def->set_body(std::move(def_body));
+
+ auto case_val = std::make_unique<ast::IntLiteral>(5);
+ std::vector<std::unique_ptr<ast::Statement>> case_body;
+ case_body.push_back(std::make_unique<ast::BreakStatement>());
+
+ auto case_stmt = std::make_unique<ast::CaseStatement>(std::move(case_val),
+ std::move(case_body));
+
+ std::vector<std::unique_ptr<ast::CaseStatement>> body;
+ body.push_back(std::move(case_stmt));
+ body.push_back(std::move(def));
+
+ auto cond = std::make_unique<ast::IdentifierExpression>("cond");
+ ast::SwitchStatement s(std::move(cond), std::move(body));
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitStatement(&s)) << g.error();
+ EXPECT_EQ(g.result(), R"( switch(cond) {
+ case 5: {
+ break;
+ }
+ default: {
+ break;
+ }
+ }
+)");
+}
+
+} // namespace
+} // namespace wgsl
+} // namespace writer
+} // namespace tint
