chromium/v8/test/unittests/compiler/turboshaft/late-load-elimination-reducer-unittest.cc

// Copyright 2024 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "src/compiler/turboshaft/late-load-elimination-reducer.h"

#include "src/compiler/turboshaft/assembler.h"
#include "src/compiler/turboshaft/copying-phase.h"
#include "src/compiler/turboshaft/machine-optimization-reducer.h"
#include "src/compiler/turboshaft/operations.h"
#include "src/compiler/turboshaft/opmasks.h"
#include "src/compiler/turboshaft/phase.h"
#include "src/compiler/turboshaft/representations.h"
#include "src/compiler/turboshaft/required-optimization-reducer.h"
#include "src/compiler/turboshaft/variable-reducer.h"
#include "test/common/flag-utils.h"
#include "test/unittests/compiler/turboshaft/reducer-test.h"

namespace v8::internal::compiler::turboshaft {

#include "src/compiler/turboshaft/define-assembler-macros.inc"

// Use like this:
// V<...> C(my_var) = ...
#define C …

class LateLoadEliminationReducerTest : public ReducerTest { … };

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * => Load[Int32]
 */
TEST_F(LateLoadEliminationReducerTest, Int32TruncatedLoad_Foldable) { … }

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * cannot be optimized because Load[Tagged] has another non-truncating use.
 */
TEST_F(LateLoadEliminationReducerTest,
       Int32TruncatedLoad_NonFoldable_AdditionalUse) { … }

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * cannot be optimized because there is another non-truncated Load that is
 * elminated by LateLoadElimination that adds additional uses.
 */
TEST_F(LateLoadEliminationReducerTest,
       Int32TruncatedLoad_NonFoldable_ReplacingOtherLoad) { … }

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * => Load[Int32]
 * because the other load that is eliminated by LateLoadElimination is also a
 * truncating load.
 */
TEST_F(LateLoadEliminationReducerTest,
       Int32TruncatedLoad_Foldable_ReplacingOtherLoad) { … }

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * cannot be optimized because this load is replaced by another load that has
 * non-truncated uses.
 */
TEST_F(LateLoadEliminationReducerTest,
       Int32TruncatedLoad_NonFoldable_ReplacedByOtherLoad) { … }

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * => Load[Int32]
 * because the other load that is replacing the load is also a truncating load.
 */
TEST_F(LateLoadEliminationReducerTest,
       Int32TruncatedLoad_Foldable_ReplacedByOtherLoad) { … }

/* TruncateInt64ToInt32(
 *     BitcastTaggedToWordPtrForTagAndSmiBits(
 *         Load[Tagged]))
 * cannot be optimized because the BitcastTaggedToWordPtrForTagAndSmiBits has an
 * additional (potentially non-truncating) use.
 */
TEST_F(LateLoadEliminationReducerTest,
       Int32TruncatedLoad_NonFoldable_AdditionalBitcastUse) { … }

#undef C

#include "src/compiler/turboshaft/undef-assembler-macros.inc"

}  // namespace v8::internal::compiler::turboshaft