[interpeter] Move to table based peephole optimizer.

Introduces a lookup table for peephole optimizations.

Fixes some tests using BytecodePeepholeOptimizer::Write() that should
have been update to use BytecodePeepholeOptimizer::WriteJump().

BUG=v8:4280
LOG=N

Review-Url: https://codereview.chromium.org/2118183002
Cr-Commit-Position: refs/heads/master@{#37819}

BUILD.gn

@@ -86,6 +86,7 @@ if (v8_enable_gdbjit == "") {
   }
 }
 
+v8_generated_peephole_source = "$target_gen_dir/bytecode-peephole-table.cc"
 v8_random_seed = "314159265"
 v8_toolset_for_shell = "host"
 
@@ -649,6 +650,25 @@ action("run_mksnapshot") {
   }
 }
 
+action("run_mkpeephole") {
+  visibility = [ ":*" ]  # Only targets in this file can depend on this.
+
+  deps = [ ":mkpeephole($v8_snapshot_toolchain)" ]
+
+  outputs = [ v8_generated_peephole_source ]
+
+  sources = []
+
+  script = "tools/run.py"
+
+  args = [
+    "./" + rebase_path(get_label_info(":mkpeephole($v8_snapshot_toolchain)",
+                                      "root_out_dir") + "/mkpeephole",
+                       root_build_dir),
+    rebase_path(v8_generated_peephole_source, root_build_dir),
+  ]
+}
+
 action("v8_dump_build_config") {
   script = "tools/testrunner/utils/dump_build_config.py"
   outputs = [
@@ -1311,6 +1331,7 @@ v8_source_set("v8_base") {
     "src/interpreter/bytecode-label.h",
     "src/interpreter/bytecode-peephole-optimizer.cc",
     "src/interpreter/bytecode-peephole-optimizer.h",
+    "src/interpreter/bytecode-peephole-table.h",
     "src/interpreter/bytecode-pipeline.cc",
     "src/interpreter/bytecode-pipeline.h",
     "src/interpreter/bytecode-register-allocator.cc",
@@ -1909,6 +1930,9 @@ v8_source_set("v8_base") {
     ":v8_libsampler",
   ]
 
+  sources += [ v8_generated_peephole_source ]
+  deps += [ ":run_mkpeephole" ]
+
   if (is_win) {
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
     cflags = [ "/wd4267" ]
@@ -2132,6 +2156,31 @@ if (current_toolchain == v8_snapshot_toolchain) {
   }
 }
 
+v8_executable("mkpeephole") {
+  # mkpeephole needs to be built for the build host so the peephole lookup
+  # table can built during build. The table depends on the properties of
+  # bytecodes that are described in bytecodes.{cc,h}.
+  visibility = [ ":*" ]  # Only targets in this file can depend on this.
+
+  sources = [
+    "src/interpreter/bytecode-peephole-optimizer.h",
+    "src/interpreter/bytecodes.cc",
+    "src/interpreter/bytecodes.h",
+    "src/interpreter/mkpeephole.cc",
+  ]
+
+  configs = [
+    ":external_config",
+    ":internal_config",
+  ]
+
+  deps = [
+    ":v8_libbase",
+    "//build/config/sanitizers:deps",
+    "//build/win:default_exe_manifest",
+  ]
+}
+
 ###############################################################################
 # Public targets
 #

src/interpreter/bytecode-peephole-optimizer.h

-// Copyright 2015 the V8 project authors. All rights reserved.
+// Copyright 2016 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.
 
 #ifndef V8_INTERPRETER_BYTECODE_PEEPHOLE_OPTIMIZER_H_
 #define V8_INTERPRETER_BYTECODE_PEEPHOLE_OPTIMIZER_H_
 
+#include "src/interpreter/bytecode-peephole-table.h"
 #include "src/interpreter/bytecode-pipeline.h"
 
 namespace v8 {
@@ -12,6 +13,7 @@ namespace internal {
 namespace interpreter {
 
 class ConstantArrayBuilder;
+class BytecodePeepholeActionAndData;
 
 // An optimization stage for performing peephole optimizations on
 // generated bytecode. The optimizer may buffer one bytecode
@@ -32,31 +34,26 @@ class BytecodePeepholeOptimizer final : public BytecodePipelineStage,
       Handle<FixedArray> handler_table) override;
 
  private:
-  BytecodeNode* OptimizeAndEmitLast(BytecodeNode* current);
-  BytecodeNode* Optimize(BytecodeNode* current);
-  void Flush();
+#define DECLARE_ACTION(Action)          \
+  void Action(BytecodeNode* const node, \
+              const PeepholeActionAndData* const action_data = nullptr);
+  PEEPHOLE_ACTION_LIST(DECLARE_ACTION)
+#undef DECLARE_ACTION
 
-  void TryToRemoveLastExpressionPosition(const BytecodeNode* const current);
-  bool TransformCurrentBytecode(BytecodeNode* const current);
-  bool TransformLastAndCurrentBytecodes(BytecodeNode* const current);
-  bool CanElideCurrent(const BytecodeNode* const current) const;
-  bool CanElideLast(const BytecodeNode* const current) const;
+  void ApplyPeepholeAction(BytecodeNode* const node);
+  void Flush();
   bool CanElideLastBasedOnSourcePosition(
       const BytecodeNode* const current) const;
-
-  // Simple substitution methods.
-  bool RemoveToBooleanFromJump(BytecodeNode* const current);
-  bool RemoveToBooleanFromLogicalNot(BytecodeNode* const current);
-
   void InvalidateLast();
   bool LastIsValid() const;
   void SetLast(const BytecodeNode* const node);
 
-  bool LastBytecodePutsNameInAccumulator() const;
-
   Handle<Object> GetConstantForIndexOperand(const BytecodeNode* const node,
                                             int index) const;
 
+  BytecodePipelineStage* next_stage() const { return next_stage_; }
+  BytecodeNode* last() { return &last_; }
+
   ConstantArrayBuilder* constant_array_builder_;
   BytecodePipelineStage* next_stage_;
   BytecodeNode last_;

src/interpreter/bytecode-peephole-table.h

+// Copyright 2016 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.
+
+#ifndef V8_INTERPRETER_BYTECODE_PEEPHOLE_TABLE_H_
+#define V8_INTERPRETER_BYTECODE_PEEPHOLE_TABLE_H_
+
+#include "src/interpreter/bytecodes.h"
+
+namespace v8 {
+namespace internal {
+namespace interpreter {
+
+#define PEEPHOLE_NON_JUMP_ACTION_LIST(V)            \
+  V(DefaultAction)                                  \
+  V(UpdateLastAction)                               \
+  V(UpdateLastIfSourceInfoPresentAction)            \
+  V(ElideCurrentAction)                             \
+  V(ElideCurrentIfOperand0MatchesAction)            \
+  V(ElideCurrentIfLoadingNameConstantAction)        \
+  V(ElideLastAction)                                \
+  V(ChangeBytecodeAction)                           \
+  V(TransformLdaStarToLdrLdarAction)                \
+  V(TransformLdaSmiBinaryOpToBinaryOpWithSmiAction) \
+  V(TransformLdaZeroBinaryOpToBinaryOpWithZeroAction)
+
+#define PEEPHOLE_JUMP_ACTION_LIST(V) \
+  V(DefaultJumpAction)               \
+  V(UpdateLastJumpAction)            \
+  V(ChangeJumpBytecodeAction)        \
+  V(ElideLastBeforeJumpAction)
+
+#define PEEPHOLE_ACTION_LIST(V)    \
+  PEEPHOLE_NON_JUMP_ACTION_LIST(V) \
+  PEEPHOLE_JUMP_ACTION_LIST(V)
+
+// Actions to take when a pair of bytes is encountered. A handler
+// exists for each action.
+enum class PeepholeAction : uint8_t {
+#define DECLARE_PEEPHOLE_ACTION(Action) k##Action,
+  PEEPHOLE_ACTION_LIST(DECLARE_PEEPHOLE_ACTION)
+#undef DECLARE_PEEPHOLE_ACTION
+};
+
+// Tuple of action to take when pair of bytecodes is encountered and
+// optional data to invoke handler with.
+struct PeepholeActionAndData final {
+  // Action to take when tuple of bytecodes encountered.
+  PeepholeAction action;
+
+  // Replacement bytecode (if valid).
+  Bytecode bytecode;
+};
+
+// Lookup table for matching pairs of bytecodes to peephole optimization
+// actions. The contents of the table are generated by mkpeephole.cc.
+struct PeepholeActionTable final {
+ public:
+  static const PeepholeActionAndData* Lookup(Bytecode last, Bytecode current);
+
+ private:
+  static const size_t kNumberOfBytecodes =
+      static_cast<size_t>(Bytecode::kLast) + 1;
+
+  static const PeepholeActionAndData row_data_[][kNumberOfBytecodes];
+  static const PeepholeActionAndData* const row_[kNumberOfBytecodes];
+};
+
+}  // namespace interpreter
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_INTERPRETER_BYTECODE_PEEPHOLE_TABLE_H_

src/interpreter/bytecodes.cc

@@ -476,11 +476,6 @@ bool Bytecodes::IsLdarOrStar(Bytecode bytecode) {
   return bytecode == Bytecode::kLdar || bytecode == Bytecode::kStar;
 }
 
-// static
-bool Bytecodes::IsLdaSmiOrLdaZero(Bytecode bytecode) {
-  return bytecode == Bytecode::kLdaSmi || bytecode == Bytecode::kLdaZero;
-}
-
 // static
 bool Bytecodes::IsBytecodeWithScalableOperands(Bytecode bytecode) {
   switch (bytecode) {
@@ -508,6 +503,11 @@ bool Bytecodes::IsPrefixScalingBytecode(Bytecode bytecode) {
   }
 }
 
+// static
+bool Bytecodes::PutsNameInAccumulator(Bytecode bytecode) {
+  return bytecode == Bytecode::kToName || bytecode == Bytecode::kTypeOf;
+}
+
 // static
 bool Bytecodes::IsJumpOrReturn(Bytecode bytecode) {
   return bytecode == Bytecode::kReturn || IsJump(bytecode);

src/interpreter/bytecodes.h

@@ -514,15 +514,15 @@ class Bytecodes final {
   // Returns true if the bytecode is Ldar or Star.
   static bool IsLdarOrStar(Bytecode bytecode);
 
-  // Returns true if the bytecode is LdaSmi or LdaZero.
-  static bool IsLdaSmiOrLdaZero(Bytecode bytecode);
-
   // Returns true if the bytecode has wider operand forms.
   static bool IsBytecodeWithScalableOperands(Bytecode bytecode);
 
   // Returns true if the bytecode is a scaling prefix bytecode.
   static bool IsPrefixScalingBytecode(Bytecode bytecode);
 
+  // Returns true if |bytecode| puts a name in the accumulator.
+  static bool PutsNameInAccumulator(Bytecode bytecode);
+
   // Returns true if |operand_type| is any type of register operand.
   static bool IsRegisterOperandType(OperandType operand_type);
 

src/v8.gyp

@@ -35,6 +35,7 @@
     'v8_extra_library_files%': [],
     'v8_experimental_extra_library_files%': [],
     'mksnapshot_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mksnapshot<(EXECUTABLE_SUFFIX)',
+    'mkpeephole_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mkpeephole<(EXECUTABLE_SUFFIX)',
   },
   'includes': ['../gypfiles/toolchain.gypi', '../gypfiles/features.gypi'],
   'targets': [
@@ -382,13 +383,31 @@
         'v8_libbase',
         'v8_libsampler',
       ],
+      'objs': ['foo.o'],
       'variables': {
         'optimize': 'max',
       },
       'include_dirs+': [
         '..',
         '<(DEPTH)',
+        '<(SHARED_INTERMEDIATE_DIR)'
+      ],
+      'actions':[{
+        'action_name': 'run mkpeephole',
+        'inputs': ['<(mkpeephole_exec)'],
+        'outputs': ['<(INTERMEDIATE_DIR)/bytecode-peephole-table.cc'],
+        'action': ['<(mkpeephole_exec)', '<(INTERMEDIATE_DIR)/bytecode-peephole-table.cc' ],
+        'process_outputs_as_sources': 1,
+        'conditions': [
+          ['want_separate_host_toolset==1', {
+            'dependencies': ['mkpeephole#host'],
+            'toolsets': ['host'],
+          }, {
+            'dependencies': ['mkpeephole'],
+            'toolsets': ['target'],
+          }],
         ],
+      }],
       'sources': [  ### gcmole(all) ###
         '../include/v8-debug.h',
         '../include/v8-experimental.h',
@@ -929,6 +948,7 @@
         'interpreter/bytecode-label.h',
         'interpreter/bytecode-peephole-optimizer.cc',
         'interpreter/bytecode-peephole-optimizer.h',
+        'interpreter/bytecode-peephole-table.h',
         'interpreter/bytecode-pipeline.cc',
         'interpreter/bytecode-pipeline.h',
         'interpreter/bytecode-register.cc',
@@ -2315,5 +2335,26 @@
         }],
       ],
     },
+    {
+      'target_name': 'mkpeephole',
+      'type': 'executable',
+      'dependencies': [ 'v8_libbase' ],
+      'include_dirs+': [
+        '..',
+       ],
+      'sources': [
+        'interpreter/bytecode-peephole-table.h',
+        'interpreter/bytecodes.h',
+        'interpreter/bytecodes.cc',
+        'interpreter/mkpeephole.cc'
+      ],
+      'conditions': [
+        ['want_separate_host_toolset==1', {
+          'toolsets': ['host'],
+        }, {
+          'toolsets': ['target'],
+        }],
+      ],
+    },
   ],
 }

test/cctest/interpreter/bytecode_expectations/ConstVariable.golden

@@ -59,7 +59,7 @@ snippet: "
 "
 frame size: 3
 parameter count: 1
-bytecode array length: 33
+bytecode array length: 31
 bytecodes: [
                 B(LdaTheHole),
                 B(Star), R(0),
@@ -73,7 +73,6 @@ bytecodes: [
   /*   48 E> */ B(CallRuntime), U16(Runtime::kThrowReferenceError), R(2), U8(1),
                 B(CallRuntime), U16(Runtime::kThrowConstAssignError), R(0), U8(0),
                 B(Mov), R(1), R(0),
-                B(Ldar), R(0),
                 B(LdaUndefined),
   /*   55 S> */ B(Return),
 ]

test/cctest/interpreter/bytecode_expectations/LetVariable.golden

@@ -59,7 +59,7 @@ snippet: "
 "
 frame size: 3
 parameter count: 1
-bytecode array length: 28
+bytecode array length: 26
 bytecodes: [
                 B(LdaTheHole),
                 B(Star), R(0),
@@ -72,7 +72,6 @@ bytecodes: [
                 B(Star), R(2),
   /*   45 E> */ B(CallRuntime), U16(Runtime::kThrowReferenceError), R(2), U8(1),
                 B(Mov), R(1), R(0),
-                B(Ldar), R(0),
                 B(LdaUndefined),
   /*   52 S> */ B(Return),
 ]

test/unittests/interpreter/bytecode-peephole-optimizer-unittest.cc

@@ -134,12 +134,10 @@ TEST_F(BytecodePeepholeOptimizerTest, KeepStatementNop) {
 TEST_F(BytecodePeepholeOptimizerTest, KeepJumpIfToBooleanTrue) {
   BytecodeNode first(Bytecode::kLdaNull);
   BytecodeNode second(Bytecode::kJumpIfToBooleanTrue, 3);
+  BytecodeLabel label;
   optimizer()->Write(&first);
   CHECK_EQ(write_count(), 0);
-  optimizer()->Write(&second);
-  CHECK_EQ(write_count(), 1);
-  CHECK_EQ(last_written(), first);
-  Flush();
+  optimizer()->WriteJump(&second, &label);
   CHECK_EQ(write_count(), 2);
   CHECK_EQ(last_written(), second);
 }
@@ -147,15 +145,12 @@ TEST_F(BytecodePeepholeOptimizerTest, KeepJumpIfToBooleanTrue) {
 TEST_F(BytecodePeepholeOptimizerTest, ElideJumpIfToBooleanTrue) {
   BytecodeNode first(Bytecode::kLdaTrue);
   BytecodeNode second(Bytecode::kJumpIfToBooleanTrue, 3);
+  BytecodeLabel label;
   optimizer()->Write(&first);
   CHECK_EQ(write_count(), 0);
-  optimizer()->Write(&second);
-  CHECK_EQ(write_count(), 1);
-  CHECK_EQ(last_written(), first);
-  Flush();
+  optimizer()->WriteJump(&second, &label);
   CHECK_EQ(write_count(), 2);
-  CHECK_EQ(last_written().bytecode(), Bytecode::kJumpIfTrue);
-  CHECK_EQ(last_written().operand(0), second.operand(0));
+  CHECK_EQ(last_written(), second);
 }
 
 TEST_F(BytecodePeepholeOptimizerTest, KeepToBooleanLogicalNot) {
@@ -204,12 +199,11 @@ TEST_F(BytecodePeepholeOptimizerTest, StarRxLdarRx) {
   BytecodeNode first(Bytecode::kStar, Register(0).ToOperand());
   BytecodeNode second(Bytecode::kLdar, Register(0).ToOperand());
   optimizer()->Write(&first);
-  CHECK_EQ(write_count(), 0);
   optimizer()->Write(&second);
-  CHECK_EQ(write_count(), 1);
-  CHECK_EQ(last_written(), first);
+  CHECK_EQ(write_count(), 0);
   Flush();
   CHECK_EQ(write_count(), 1);
+  CHECK_EQ(last_written(), first);
 }
 
 TEST_F(BytecodePeepholeOptimizerTest, StarRxLdarRxStatement) {
@@ -262,11 +256,10 @@ TEST_F(BytecodePeepholeOptimizerTest, ToNameToName) {
   BytecodeNode first(Bytecode::kToName);
   BytecodeNode second(Bytecode::kToName);
   optimizer()->Write(&first);
-  CHECK_EQ(write_count(), 0);
   optimizer()->Write(&second);
-  CHECK_EQ(write_count(), 1);
-  CHECK_EQ(last_written(), first);
+  CHECK_EQ(write_count(), 0);
   Flush();
+  CHECK_EQ(last_written(), first);
   CHECK_EQ(write_count(), 1);
 }
 
@@ -274,12 +267,11 @@ TEST_F(BytecodePeepholeOptimizerTest, TypeOfToName) {
   BytecodeNode first(Bytecode::kTypeOf);
   BytecodeNode second(Bytecode::kToName);
   optimizer()->Write(&first);
-  CHECK_EQ(write_count(), 0);
   optimizer()->Write(&second);
-  CHECK_EQ(write_count(), 1);
-  CHECK_EQ(last_written(), first);
+  CHECK_EQ(write_count(), 0);
   Flush();
   CHECK_EQ(write_count(), 1);
+  CHECK_EQ(last_written(), first);
 }
 
 TEST_F(BytecodePeepholeOptimizerTest, LdaConstantStringToName) {
@@ -289,12 +281,11 @@ TEST_F(BytecodePeepholeOptimizerTest, LdaConstantStringToName) {
   BytecodeNode first(Bytecode::kLdaConstant, static_cast<uint32_t>(index));
   BytecodeNode second(Bytecode::kToName);
   optimizer()->Write(&first);
-  CHECK_EQ(write_count(), 0);
   optimizer()->Write(&second);
-  CHECK_EQ(write_count(), 1);
-  CHECK_EQ(last_written(), first);
+  CHECK_EQ(write_count(), 0);
   Flush();
   CHECK_EQ(write_count(), 1);
+  CHECK_EQ(last_written(), first);
 }
 
 TEST_F(BytecodePeepholeOptimizerTest, LdaConstantNumberToName) {