[spirv-writer] Add DiscardStatement support.
This CL updates the spirv-writer to emit the DiscardStatement as an
OpKill.
Bug: tint:163
Change-Id: Ic2514ee8a4ef7ef0220fc2e1145f8df0c3d32069
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/25641
Reviewed-by: David Neto <dneto@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index c31ebff..fa52285 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -803,6 +803,7 @@
"src/writer/spirv/builder_call_test.cc",
"src/writer/spirv/builder_cast_expression_test.cc",
"src/writer/spirv/builder_constructor_expression_test.cc",
+ "src/writer/spirv/builder_discard_test.cc",
"src/writer/spirv/builder_entry_point_test.cc",
"src/writer/spirv/builder_function_test.cc",
"src/writer/spirv/builder_function_variable_test.cc",
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index d2807b9..4f35b61 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -457,6 +457,7 @@
writer/spirv/builder_call_test.cc
writer/spirv/builder_cast_expression_test.cc
writer/spirv/builder_constructor_expression_test.cc
+ writer/spirv/builder_discard_test.cc
writer/spirv/builder_entry_point_test.cc
writer/spirv/builder_function_test.cc
writer/spirv/builder_function_variable_test.cc
diff --git a/src/writer/spirv/builder.cc b/src/writer/spirv/builder.cc
index d5c956f..c21288f 100644
--- a/src/writer/spirv/builder.cc
+++ b/src/writer/spirv/builder.cc
@@ -105,8 +105,8 @@
}
auto* last = stmts.back().get();
- return last->IsBreak() || last->IsContinue() || last->IsReturn() ||
- last->IsKill() || last->IsFallthrough();
+ return last->IsBreak() || last->IsContinue() || last->IsDiscard() ||
+ last->IsReturn() || last->IsKill() || last->IsFallthrough();
}
uint32_t IndexFromName(char name) {
@@ -276,6 +276,14 @@
// TODO(dsinclair): This is generating an OpKill but the semantics of kill
// haven't been defined for WGSL yet. So, this may need to change.
// https://github.com/gpuweb/gpuweb/issues/676
+bool Builder::GenerateDiscardStatement(ast::DiscardStatement*) {
+ push_function_inst(spv::Op::OpKill, {});
+ return true;
+}
+
+// TODO(dsinclair): This is generating an OpKill but the semantics of kill
+// haven't been defined for WGSL yet. So, this may need to change.
+// https://github.com/gpuweb/gpuweb/issues/676
bool Builder::GenerateKillStatement(ast::KillStatement*) {
push_function_inst(spv::Op::OpKill, {});
return true;
@@ -1816,6 +1824,9 @@
if (stmt->IsContinue()) {
return GenerateContinueStatement(stmt->AsContinue());
}
+ if (stmt->IsDiscard()) {
+ return GenerateDiscardStatement(stmt->AsDiscard());
+ }
if (stmt->IsFallthrough()) {
// Do nothing here, the fallthrough gets handled by the switch code.
return true;
diff --git a/src/writer/spirv/builder.h b/src/writer/spirv/builder.h
index 91505e8..28f893a 100644
--- a/src/writer/spirv/builder.h
+++ b/src/writer/spirv/builder.h
@@ -175,6 +175,10 @@
/// @param stmt the statement to generate
/// @returns true if the statement was successfully generated
bool GenerateContinueStatement(ast::ContinueStatement* stmt);
+ /// Generates a discard statement
+ /// @param stmt the statement to generate
+ /// @returns true if the statement was successfully generated
+ bool GenerateDiscardStatement(ast::DiscardStatement* stmt);
/// Generates a kill statement
/// @param stmt the statement to generate
/// @returns true if the statement was successfully generated
diff --git a/src/writer/spirv/builder_discard_test.cc b/src/writer/spirv/builder_discard_test.cc
new file mode 100644
index 0000000..596a24c
--- /dev/null
+++ b/src/writer/spirv/builder_discard_test.cc
@@ -0,0 +1,43 @@
+// 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/discard_statement.h"
+#include "src/context.h"
+#include "src/type_determiner.h"
+#include "src/writer/spirv/builder.h"
+#include "src/writer/spirv/spv_dump.h"
+
+namespace tint {
+namespace writer {
+namespace spirv {
+namespace {
+
+using BuilderTest = testing::Test;
+
+TEST_F(BuilderTest, Discard) {
+ ast::DiscardStatement expr;
+
+ ast::Module mod;
+ Builder b(&mod);
+ b.push_function(Function{});
+ EXPECT_EQ(b.GenerateStatement(&expr), 1u) << b.error();
+ EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()), R"(OpKill
+)");
+}
+
+} // namespace
+} // namespace spirv
+} // namespace writer
+} // namespace tint
