[msl-writer] Emit switch statements.
This CL adds support for switch and case statements into the MSL writer.
Bug: tint:8
Change-Id: Ib51f943e8476c0ecfd45e9131404f96934c6e21f
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/24180
Reviewed-by: David Neto <dneto@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 7c13039..78b3515 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -890,6 +890,7 @@
"src/writer/msl/generator_impl_assign_test.cc",
"src/writer/msl/generator_impl_binary_test.cc",
"src/writer/msl/generator_impl_break_test.cc",
+ "src/writer/msl/generator_impl_case_test.cc",
"src/writer/msl/generator_impl_cast_test.cc",
"src/writer/msl/generator_impl_constructor_test.cc",
"src/writer/msl/generator_impl_continue_test.cc",
@@ -900,6 +901,7 @@
"src/writer/msl/generator_impl_loop_test.cc",
"src/writer/msl/generator_impl_member_accessor_test.cc",
"src/writer/msl/generator_impl_return_test.cc",
+ "src/writer/msl/generator_impl_switch_test.cc",
"src/writer/msl/generator_impl_test.cc",
"src/writer/msl/generator_impl_type_test.cc",
"src/writer/msl/generator_impl_unary_op_test.cc",
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 82f26d0..3976a91 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -498,6 +498,7 @@
writer/msl/generator_impl_assign_test.cc
writer/msl/generator_impl_binary_test.cc
writer/msl/generator_impl_break_test.cc
+ writer/msl/generator_impl_case_test.cc
writer/msl/generator_impl_cast_test.cc
writer/msl/generator_impl_constructor_test.cc
writer/msl/generator_impl_continue_test.cc
@@ -508,6 +509,7 @@
writer/msl/generator_impl_loop_test.cc
writer/msl/generator_impl_member_accessor_test.cc
writer/msl/generator_impl_return_test.cc
+ writer/msl/generator_impl_switch_test.cc
writer/msl/generator_impl_test.cc
writer/msl/generator_impl_type_test.cc
writer/msl/generator_impl_unary_op_test.cc
diff --git a/src/writer/msl/generator_impl.cc b/src/writer/msl/generator_impl.cc
index 466688e..2ab8b02 100644
--- a/src/writer/msl/generator_impl.cc
+++ b/src/writer/msl/generator_impl.cc
@@ -20,6 +20,7 @@
#include "src/ast/binary_expression.h"
#include "src/ast/bool_literal.h"
#include "src/ast/break_statement.h"
+#include "src/ast/case_statement.h"
#include "src/ast/cast_expression.h"
#include "src/ast/continue_statement.h"
#include "src/ast/else_statement.h"
@@ -31,6 +32,7 @@
#include "src/ast/member_accessor_expression.h"
#include "src/ast/return_statement.h"
#include "src/ast/sint_literal.h"
+#include "src/ast/switch_statement.h"
#include "src/ast/type/alias_type.h"
#include "src/ast/type/array_type.h"
#include "src/ast/type/bool_type.h"
@@ -48,6 +50,17 @@
namespace tint {
namespace writer {
namespace msl {
+namespace {
+
+bool last_is_break_or_fallthrough(const ast::StatementList& stmts) {
+ if (stmts.empty()) {
+ return false;
+ }
+
+ return stmts.back()->IsBreak() || stmts.back()->IsFallthrough();
+}
+
+} // namespace
GeneratorImpl::GeneratorImpl() = default;
@@ -222,6 +235,50 @@
return true;
}
+bool GeneratorImpl::EmitCase(ast::CaseStatement* stmt) {
+ make_indent();
+
+ if (stmt->IsDefault()) {
+ out_ << "default:";
+ } else {
+ bool first = true;
+ for (const auto& selector : stmt->selectors()) {
+ if (!first) {
+ out_ << std::endl;
+ make_indent();
+ }
+ first = false;
+
+ out_ << "case ";
+ if (!EmitLiteral(selector.get())) {
+ return false;
+ }
+ out_ << ":";
+ }
+ }
+
+ out_ << " {" << std::endl;
+
+ increment_indent();
+
+ for (const auto& s : stmt->body()) {
+ if (!EmitStatement(s.get())) {
+ return false;
+ }
+ }
+
+ if (!last_is_break_or_fallthrough(stmt->body())) {
+ make_indent();
+ out_ << "break;" << std::endl;
+ }
+
+ decrement_indent();
+ make_indent();
+ out_ << "}" << std::endl;
+
+ return true;
+}
+
bool GeneratorImpl::EmitCast(ast::CastExpression* expr) {
if (!EmitType(expr->type(), "")) {
return false;
@@ -567,6 +624,11 @@
if (stmt->IsContinue()) {
return EmitContinue(stmt->AsContinue());
}
+ if (stmt->IsFallthrough()) {
+ make_indent();
+ out_ << "/* fallthrough */" << std::endl;
+ return true;
+ }
if (stmt->IsIf()) {
return EmitIf(stmt->AsIf());
}
@@ -579,11 +641,38 @@
if (stmt->IsReturn()) {
return EmitReturn(stmt->AsReturn());
}
+ if (stmt->IsSwitch()) {
+ return EmitSwitch(stmt->AsSwitch());
+ }
error_ = "unknown statement type";
return false;
}
+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::EmitType(ast::type::Type* type, const std::string& name) {
if (type->IsAlias()) {
auto* alias = type->AsAlias();
diff --git a/src/writer/msl/generator_impl.h b/src/writer/msl/generator_impl.h
index d74ff04..7573091 100644
--- a/src/writer/msl/generator_impl.h
+++ b/src/writer/msl/generator_impl.h
@@ -64,6 +64,10 @@
/// @param stmt the statement to emit
/// @returns true if the statement was emitted successfully
bool EmitBreak(ast::BreakStatement* stmt);
+ /// Handles a case statement
+ /// @param stmt the statement
+ /// @returns true if the statment was emitted successfully
+ bool EmitCase(ast::CaseStatement* stmt);
/// Handles generating a cast expression
/// @param expr the cast expression
/// @returns true if the cast was emitted
@@ -135,6 +139,10 @@
/// @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
/// @param name the name of the variable, only used for array emission
diff --git a/src/writer/msl/generator_impl_case_test.cc b/src/writer/msl/generator_impl_case_test.cc
new file mode 100644
index 0000000..a53f207
--- /dev/null
+++ b/src/writer/msl/generator_impl_case_test.cc
@@ -0,0 +1,135 @@
+// 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 "gtest/gtest.h"
+#include "src/ast/break_statement.h"
+#include "src/ast/case_statement.h"
+#include "src/ast/fallthrough_statement.h"
+#include "src/ast/identifier_expression.h"
+#include "src/ast/sint_literal.h"
+#include "src/ast/type/i32_type.h"
+#include "src/writer/msl/generator_impl.h"
+
+namespace tint {
+namespace writer {
+namespace msl {
+namespace {
+
+using MslGeneratorImplTest = testing::Test;
+
+TEST_F(MslGeneratorImplTest, Emit_Case) {
+ ast::type::I32Type i32;
+
+ ast::StatementList body;
+ body.push_back(std::make_unique<ast::BreakStatement>());
+
+ ast::CaseSelectorList lit;
+ lit.push_back(std::make_unique<ast::SintLiteral>(&i32, 5));
+ ast::CaseStatement c(std::move(lit), std::move(body));
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitCase(&c)) << g.error();
+ EXPECT_EQ(g.result(), R"( case 5: {
+ break;
+ }
+)");
+}
+
+TEST_F(MslGeneratorImplTest, Emit_Case_BreaksByDefault) {
+ ast::type::I32Type i32;
+
+ ast::StatementList body;
+
+ ast::CaseSelectorList lit;
+ lit.push_back(std::make_unique<ast::SintLiteral>(&i32, 5));
+ ast::CaseStatement c(std::move(lit), std::move(body));
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitCase(&c)) << g.error();
+ EXPECT_EQ(g.result(), R"( case 5: {
+ break;
+ }
+)");
+}
+
+TEST_F(MslGeneratorImplTest, Emit_Case_WithFallthrough) {
+ ast::type::I32Type i32;
+
+ ast::StatementList body;
+ body.push_back(std::make_unique<ast::FallthroughStatement>());
+
+ ast::CaseSelectorList lit;
+ lit.push_back(std::make_unique<ast::SintLiteral>(&i32, 5));
+ ast::CaseStatement c(std::move(lit), std::move(body));
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitCase(&c)) << g.error();
+ EXPECT_EQ(g.result(), R"( case 5: {
+ /* fallthrough */
+ }
+)");
+}
+
+TEST_F(MslGeneratorImplTest, Emit_Case_MultipleSelectors) {
+ ast::type::I32Type i32;
+
+ ast::StatementList body;
+ body.push_back(std::make_unique<ast::BreakStatement>());
+
+ ast::CaseSelectorList lit;
+ lit.push_back(std::make_unique<ast::SintLiteral>(&i32, 5));
+ lit.push_back(std::make_unique<ast::SintLiteral>(&i32, 6));
+ ast::CaseStatement c(std::move(lit), std::move(body));
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitCase(&c)) << g.error();
+ EXPECT_EQ(g.result(), R"( case 5:
+ case 6: {
+ break;
+ }
+)");
+}
+
+TEST_F(MslGeneratorImplTest, Emit_Case_Default) {
+ ast::CaseStatement c;
+
+ ast::StatementList body;
+ body.push_back(std::make_unique<ast::BreakStatement>());
+
+ c.set_body(std::move(body));
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitCase(&c)) << g.error();
+ EXPECT_EQ(g.result(), R"( default: {
+ break;
+ }
+)");
+}
+
+} // namespace
+} // namespace msl
+} // namespace writer
+} // namespace tint
diff --git a/src/writer/msl/generator_impl_switch_test.cc b/src/writer/msl/generator_impl_switch_test.cc
new file mode 100644
index 0000000..56a919d
--- /dev/null
+++ b/src/writer/msl/generator_impl_switch_test.cc
@@ -0,0 +1,74 @@
+// 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 "gtest/gtest.h"
+#include "src/ast/break_statement.h"
+#include "src/ast/case_statement.h"
+#include "src/ast/identifier_expression.h"
+#include "src/ast/sint_literal.h"
+#include "src/ast/switch_statement.h"
+#include "src/ast/type/i32_type.h"
+#include "src/writer/msl/generator_impl.h"
+
+namespace tint {
+namespace writer {
+namespace msl {
+namespace {
+
+using MslGeneratorImplTest = testing::Test;
+
+TEST_F(MslGeneratorImplTest, Emit_Switch) {
+ auto def = std::make_unique<ast::CaseStatement>();
+ ast::StatementList def_body;
+ def_body.push_back(std::make_unique<ast::BreakStatement>());
+ def->set_body(std::move(def_body));
+
+ ast::type::I32Type i32;
+ ast::CaseSelectorList case_val;
+ case_val.push_back(std::make_unique<ast::SintLiteral>(&i32, 5));
+
+ ast::StatementList 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));
+
+ ast::CaseStatementList 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 msl
+} // namespace writer
+} // namespace tint
