[spirv-writer] Add start of cast support.
This CL starts support for the cast expression. It adds the i32 to f32
conversion path.
Bug: tint:5
Change-Id: Id1eafc38592060c4b5b91964302d79a847e2edaf
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/20628
Reviewed-by: David Neto <dneto@google.com>
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index a47d829..61bc317 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -431,6 +431,7 @@
writer/spirv/builder_assign_test.cc
writer/spirv/builder_binary_expression_test.cc
writer/spirv/builder_call_test.cc
+ writer/spirv/builder_cast_expression_test.cc
writer/spirv/builder_constructor_expression_test.cc
writer/spirv/builder_entry_point_test.cc
writer/spirv/builder_function_test.cc
diff --git a/src/type_determiner.cc b/src/type_determiner.cc
index 6a1f1d1..31e66bd 100644
--- a/src/type_determiner.cc
+++ b/src/type_determiner.cc
@@ -359,6 +359,10 @@
}
bool TypeDeterminer::DetermineCast(ast::CastExpression* expr) {
+ if (!DetermineResultType(expr->expr())) {
+ return false;
+ }
+
expr->set_result_type(expr->type());
return true;
}
diff --git a/src/writer/spirv/builder.cc b/src/writer/spirv/builder.cc
index 8cd55d8..680abd3 100644
--- a/src/writer/spirv/builder.cc
+++ b/src/writer/spirv/builder.cc
@@ -25,6 +25,7 @@
#include "src/ast/bool_literal.h"
#include "src/ast/builtin_decoration.h"
#include "src/ast/call_expression.h"
+#include "src/ast/cast_expression.h"
#include "src/ast/constructor_expression.h"
#include "src/ast/decorated_variable.h"
#include "src/ast/else_statement.h"
@@ -297,6 +298,9 @@
if (expr->IsCall()) {
return GenerateCallExpression(expr->AsCall());
}
+ if (expr->IsCast()) {
+ return GenerateCastExpression(expr->AsCast());
+ }
if (expr->IsConstructor()) {
return GenerateConstructorExpression(expr->AsConstructor(), false);
}
@@ -1145,6 +1149,44 @@
return result_id;
}
+uint32_t Builder::GenerateCastExpression(ast::CastExpression* cast) {
+ auto result = result_op();
+ auto result_id = result.to_i();
+
+ auto result_type_id = GenerateTypeIfNeeded(cast->result_type());
+ if (result_type_id == 0) {
+ return 0;
+ }
+
+ auto val_id = GenerateExpression(cast->expr());
+ if (val_id == 0) {
+ return 0;
+ }
+
+ auto* to_type = cast->result_type()->UnwrapPtrIfNeeded();
+ auto* from_type = cast->expr()->result_type()->UnwrapPtrIfNeeded();
+
+ spv::Op op = spv::Op::OpNop;
+ if (from_type->IsI32() && to_type->IsF32()) {
+ op = spv::Op::OpConvertSToF;
+ } else if (from_type->IsU32() && to_type->IsF32()) {
+ op = spv::Op::OpConvertUToF;
+ } else if (from_type->IsF32() && to_type->IsI32()) {
+ op = spv::Op::OpConvertFToS;
+ } else if (from_type->IsF32() && to_type->IsU32()) {
+ op = spv::Op::OpConvertFToU;
+ }
+ if (op == spv::Op::OpNop) {
+ error_ = "unable to determine conversion type for cast";
+ return 0;
+ }
+
+ push_function_inst(
+ op, {Operand::Int(result_type_id), result, Operand::Int(val_id)});
+
+ return result_id;
+}
+
bool Builder::GenerateConditionalBlock(
ast::Expression* cond,
const ast::StatementList& true_body,
diff --git a/src/writer/spirv/builder.h b/src/writer/spirv/builder.h
index f3a40d2..87f8b24 100644
--- a/src/writer/spirv/builder.h
+++ b/src/writer/spirv/builder.h
@@ -279,6 +279,10 @@
/// @param expr the expression to generate
/// @returns the expression ID on success or 0 otherwise
uint32_t GenerateCallExpression(ast::CallExpression* expr);
+ /// Generates a cast expression
+ /// @param expr the expression to generate
+ /// @returns the expression ID on success or 0 otherwise
+ uint32_t GenerateCastExpression(ast::CastExpression* expr);
/// Generates a loop statement
/// @param stmt the statement to generate
/// @returns true on successful generation
diff --git a/src/writer/spirv/builder_cast_expression_test.cc b/src/writer/spirv/builder_cast_expression_test.cc
new file mode 100644
index 0000000..0af27a2
--- /dev/null
+++ b/src/writer/spirv/builder_cast_expression_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 "gtest/gtest.h"
+#include "src/ast/cast_expression.h"
+#include "src/ast/float_literal.h"
+#include "src/ast/int_literal.h"
+#include "src/ast/module.h"
+#include "src/ast/scalar_constructor_expression.h"
+#include "src/ast/type/f32_type.h"
+#include "src/ast/type/i32_type.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, DISABLED_Cast_FloatToU32) {}
+
+TEST_F(BuilderTest, DISABLED_Cast_FloatToI32) {}
+
+TEST_F(BuilderTest, Cast_I32ToFloat) {
+ ast::type::I32Type i32;
+ ast::type::F32Type f32;
+
+ ast::CastExpression cast(&f32,
+ std::make_unique<ast::ScalarConstructorExpression>(
+ std::make_unique<ast::IntLiteral>(&i32, 2)));
+
+ Context ctx;
+ ast::Module mod;
+ TypeDeterminer td(&ctx, &mod);
+ ASSERT_TRUE(td.DetermineResultType(&cast)) << td.error();
+
+ Builder b(&mod);
+ b.push_function(Function{});
+ EXPECT_EQ(b.GenerateCastExpression(&cast), 1u);
+
+ EXPECT_EQ(DumpInstructions(b.types()), R"(%2 = OpTypeFloat 32
+%3 = OpTypeInt 32 1
+%4 = OpConstant %3 2
+)");
+ EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
+ R"(%1 = OpConvertSToF %2 %4
+)");
+}
+
+TEST_F(BuilderTest, DISABLED_Cast_U32ToFloat) {}
+
+TEST_F(BuilderTest, DISABLED_Cast_WithLoad) {}
+
+TEST_F(BuilderTest, DISABLED_Cast_WithAlias) {}
+
+// TODO(dsinclair): Are here i32 -> u32 and u32->i32 casts?
+
+} // namespace
+} // namespace spirv
+} // namespace writer
+} // namespace tint
