[hlsl-writer] Add switch statement support
This CL adds emission of switch statements to the HLSL backend.
Bug: tint:7
Change-Id: Ie6f41031878a1f5a945f9310429d28fb0e4a98c8
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/25223
Reviewed-by: David Neto <dneto@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 8947623..2c087a5 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1024,6 +1024,7 @@
"src/writer/hlsl/generator_impl_continue_test.cc",
"src/writer/hlsl/generator_impl_identifier_test.cc",
"src/writer/hlsl/generator_impl_return_test.cc",
+ "src/writer/hlsl/generator_impl_switch_test.cc",
"src/writer/hlsl/generator_impl_test.cc",
"src/writer/hlsl/generator_impl_unary_op_test.cc",
"src/writer/hlsl/namer_test.cc",
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index e1b5e85..c5520c3 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -548,6 +548,7 @@
writer/hlsl/generator_impl_continue_test.cc
writer/hlsl/generator_impl_identifier_test.cc
writer/hlsl/generator_impl_return_test.cc
+ writer/hlsl/generator_impl_switch_test.cc
writer/hlsl/generator_impl_test.cc
writer/hlsl/generator_impl_unary_op_test.cc
writer/hlsl/namer_test.cc
diff --git a/src/writer/hlsl/generator_impl.cc b/src/writer/hlsl/generator_impl.cc
index e830366..f4105ba 100644
--- a/src/writer/hlsl/generator_impl.cc
+++ b/src/writer/hlsl/generator_impl.cc
@@ -21,6 +21,7 @@
#include "src/ast/identifier_expression.h"
#include "src/ast/return_statement.h"
#include "src/ast/sint_literal.h"
+#include "src/ast/switch_statement.h"
#include "src/ast/uint_literal.h"
#include "src/ast/unary_op_expression.h"
@@ -317,11 +318,38 @@
if (stmt->IsReturn()) {
return EmitReturn(stmt->AsReturn());
}
+ if (stmt->IsSwitch()) {
+ return EmitSwitch(stmt->AsSwitch());
+ }
error_ = "unknown statement type: " + stmt->str();
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::EmitUnaryOp(ast::UnaryOpExpression* expr) {
switch (expr->op()) {
case ast::UnaryOp::kNot:
diff --git a/src/writer/hlsl/generator_impl.h b/src/writer/hlsl/generator_impl.h
index b11e61e..8e4f546 100644
--- a/src/writer/hlsl/generator_impl.h
+++ b/src/writer/hlsl/generator_impl.h
@@ -72,6 +72,10 @@
/// @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 a unary op expression
/// @param expr the expression to emit
/// @returns true if the expression was emitted
diff --git a/src/writer/hlsl/generator_impl_switch_test.cc b/src/writer/hlsl/generator_impl_switch_test.cc
new file mode 100644
index 0000000..1c1719f
--- /dev/null
+++ b/src/writer/hlsl/generator_impl_switch_test.cc
@@ -0,0 +1,76 @@
+// 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/module.h"
+#include "src/ast/sint_literal.h"
+#include "src/ast/switch_statement.h"
+#include "src/ast/type/i32_type.h"
+#include "src/writer/hlsl/generator_impl.h"
+
+namespace tint {
+namespace writer {
+namespace hlsl {
+namespace {
+
+using HlslGeneratorImplTest = testing::Test;
+
+TEST_F(HlslGeneratorImplTest, 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));
+
+ ast::Module m;
+ GeneratorImpl g(&m);
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitStatement(&s)) << g.error();
+ EXPECT_EQ(g.result(), R"( switch(cond) {
+ case 5: {
+ break;
+ }
+ default: {
+ break;
+ }
+ }
+)");
+}
+
+} // namespace
+} // namespace hlsl
+} // namespace writer
+} // namespace tint
