[msl-writer] Emit kill statement.
This Cl adds emission of the Kill statement as `discard_fragment`. This
may need to be revised when the semantics of Kill are agreed upon.
Bug: tint:8
Change-Id: I2d09f09143b2acd0139d876e873e3c70abbc84a3
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/23841
Reviewed-by: David Neto <dneto@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index ccff5dd..4c1a7b2 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -892,6 +892,7 @@
"src/writer/msl/generator_impl_function_test.cc",
"src/writer/msl/generator_impl_identifier_test.cc",
"src/writer/msl/generator_impl_if_test.cc",
+ "src/writer/msl/generator_impl_kill_test.cc",
"src/writer/msl/generator_impl_return_test.cc",
"src/writer/msl/generator_impl_test.cc",
"src/writer/msl/generator_impl_type_test.cc",
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 27d1bfe..75136f2 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -500,6 +500,7 @@
writer/msl/generator_impl_function_test.cc
writer/msl/generator_impl_identifier_test.cc
writer/msl/generator_impl_if_test.cc
+ writer/msl/generator_impl_kill_test.cc
writer/msl/generator_impl_return_test.cc
writer/msl/generator_impl_test.cc
writer/msl/generator_impl_type_test.cc
diff --git a/src/writer/msl/generator_impl.cc b/src/writer/msl/generator_impl.cc
index 79f5afb..23171dc 100644
--- a/src/writer/msl/generator_impl.cc
+++ b/src/writer/msl/generator_impl.cc
@@ -347,6 +347,14 @@
return true;
}
+bool GeneratorImpl::EmitKill(ast::KillStatement*) {
+ make_indent();
+ // TODO(dsinclair): Verify this is correct when the kill semantics are defined
+ // for WGSL (https://github.com/gpuweb/gpuweb/issues/361)
+ out_ << "discard_fragment();" << std::endl;
+ return true;
+}
+
bool GeneratorImpl::EmitElse(ast::ElseStatement* stmt) {
if (stmt->HasCondition()) {
out_ << " else if (";
@@ -431,6 +439,9 @@
if (stmt->IsIf()) {
return EmitIf(stmt->AsIf());
}
+ if (stmt->IsKill()) {
+ return EmitKill(stmt->AsKill());
+ }
if (stmt->IsReturn()) {
return EmitReturn(stmt->AsReturn());
}
diff --git a/src/writer/msl/generator_impl.h b/src/writer/msl/generator_impl.h
index 9459089..0a3fc76 100644
--- a/src/writer/msl/generator_impl.h
+++ b/src/writer/msl/generator_impl.h
@@ -80,6 +80,10 @@
/// @param stmt the statement to emit
/// @returns true if the statement was successfully emitted
bool EmitIf(ast::IfStatement* stmt);
+ /// Handles generating a kill statement
+ /// @param stmt the kill statement
+ /// @returns true if the statement was successfully emitted
+ bool EmitKill(ast::KillStatement* stmt);
/// Handles a literal
/// @param lit the literal to emit
/// @returns true if the literal was successfully emitted
diff --git a/src/writer/msl/generator_impl_kill_test.cc b/src/writer/msl/generator_impl_kill_test.cc
new file mode 100644
index 0000000..7eb7f02
--- /dev/null
+++ b/src/writer/msl/generator_impl_kill_test.cc
@@ -0,0 +1,39 @@
+// 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 "gtest/gtest.h"
+#include "src/ast/kill_statement.h"
+#include "src/writer/msl/generator_impl.h"
+
+namespace tint {
+namespace writer {
+namespace msl {
+namespace {
+
+using MslGeneratorImplTest = testing::Test;
+
+TEST_F(MslGeneratorImplTest, Emit_Kill) {
+ ast::KillStatement k;
+
+ GeneratorImpl g;
+ g.increment_indent();
+
+ ASSERT_TRUE(g.EmitStatement(&k)) << g.error();
+ EXPECT_EQ(g.result(), " discard_fragment();\n");
+}
+
+} // namespace
+} // namespace msl
+} // namespace writer
+} // namespace tint
