Reland "[test] Avoid unnecessary std::vector allocations"

This is a reland of e737b4ce.
The issue on windows bots was fixed in https://crrev.com/c/725733.

Original change's description:
> [test] Avoid unnecessary std::vector allocations
> 
> Instead of copying an array of fixed values into an std::vector for
> each usage of the FOR_INPUTS macro, just iterate the constant data
> directly.
> This also makes the <type>_vector() functions return {constexpr Vector}
> instead of {std::vector}.
> 
> R=tebbi@chromium.org
> 
> Change-Id: Ifc3e5509b2fbf5e383c967c2f46acf2b07f7b5b4
> Reviewed-on: https://chromium-review.googlesource.com/725427
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48688}

Change-Id: I9ad5d22803bbbf35c458965497acc603cfa01b20
Reviewed-on: https://chromium-review.googlesource.com/725979Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48726}

src/vector.h

@@ -19,14 +19,14 @@ namespace internal {
 template <typename T>
 class Vector {
  public:
-  Vector() : start_(nullptr), length_(0) {}
+  constexpr Vector() : start_(nullptr), length_(0) {}
 
   Vector(T* data, size_t length) : start_(data), length_(length) {
     DCHECK(length == 0 || data != nullptr);
   }
 
   template <int N>
-  explicit Vector(T (&arr)[N]) : start_(arr), length_(N) {}
+  explicit constexpr Vector(T (&arr)[N]) : start_(arr), length_(N) {}
 
   static Vector<T> New(int length) {
     return Vector<T>(NewArray<T>(length), length);
@@ -47,13 +47,13 @@ class Vector {
   }
 
   // Returns the length of the vector as a size_t.
-  size_t size() const { return length_; }
+  constexpr size_t size() const { return length_; }
 
   // Returns whether or not the vector is empty.
-  bool is_empty() const { return length_ == 0; }
+  constexpr bool is_empty() const { return length_ == 0; }
 
   // Returns the pointer to the start of the data in the vector.
-  T* start() const { return start_; }
+  constexpr T* start() const { return start_; }
 
   // Access individual vector elements - checks bounds in debug mode.
   T& operator[](size_t index) const {
@@ -65,11 +65,14 @@ class Vector {
 
   T& first() { return start_[0]; }
 
-  T& last() { return start_[length_ - 1]; }
+  T& last() {
+    DCHECK_LT(0, length_);
+    return start_[length_ - 1];
+  }
 
   typedef T* iterator;
-  inline iterator begin() const { return &start_[0]; }
-  inline iterator end() const { return &start_[length_]; }
+  constexpr iterator begin() const { return start_; }
+  constexpr iterator end() const { return start_ + length_; }
 
   // Returns a clone of this vector with a new backing store.
   Vector<T> Clone() const {
@@ -130,8 +133,8 @@ class Vector {
   // Factory method for creating empty vectors.
   static Vector<T> empty() { return Vector<T>(nullptr, 0); }
 
-  template<typename S>
-  static Vector<T> cast(Vector<S> input) {
+  template <typename S>
+  static constexpr Vector<T> cast(Vector<S> input) {
     return Vector<T>(reinterpret_cast<T*>(input.start()),
                      input.length() * sizeof(S) / sizeof(T));
   }
@@ -214,7 +217,7 @@ inline Vector<char> MutableCStrVector(char* data, int max) {
 }
 
 template <typename T, int N>
-inline Vector<T> ArrayVector(T (&arr)[N]) {
+inline constexpr Vector<T> ArrayVector(T (&arr)[N]) {
   return Vector<T>(arr);
 }
 

test/cctest/BUILD.gn

@@ -87,6 +87,7 @@ v8_source_set("cctest_sources") {
     "compiler/test-run-unwinding-info.cc",
     "compiler/test-run-variables.cc",
     "compiler/test-run-wasm-machops.cc",
+    "compiler/value-helper.cc",
     "compiler/value-helper.h",
     "expression-type-collector-macros.h",
     "gay-fixed.cc",

test/cctest/cctest.gyp

@@ -75,6 +75,7 @@
       'compiler/test-run-stubs.cc',
       'compiler/test-run-variables.cc',
       'compiler/test-run-wasm-machops.cc',
+      'compiler/value-helper.cc',
       'compiler/value-helper.h',
       'cctest.cc',
       'cctest.h',

test/cctest/compiler/codegen-tester.cc

@@ -285,7 +285,7 @@ TEST(CompareWrapper) {
 
 
 void Int32BinopInputShapeTester::TestAllInputShapes() {
-  std::vector<int32_t> inputs = ValueHelper::int32_vector();
+  Vector<const int32_t> inputs = ValueHelper::int32_vector();
   int num_int_inputs = static_cast<int>(inputs.size());
   if (num_int_inputs > 16) num_int_inputs = 16;  // limit to 16 inputs
 

test/cctest/compiler/value-helper.cc

+// Copyright 2017 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 "test/cctest/compiler/value-helper.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+// Define constexpr arrays of ValueHelper for external references.
+constexpr int8_t ValueHelper::int8_array[];
+constexpr int16_t ValueHelper::int16_array[];
+constexpr uint32_t ValueHelper::uint32_array[];
+constexpr uint64_t ValueHelper::uint64_array[];
+constexpr float ValueHelper::float32_array[];
+constexpr double ValueHelper::float64_array[];
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8

test/cctest/wasm/test-c-wasm-entry.cc

@@ -100,8 +100,7 @@ TEST(TestCWasmEntryArgPassing_int32) {
        WASM_I32_ADD(WASM_I32_MUL(WASM_I32V_1(2), WASM_GET_LOCAL(0)), WASM_ONE)},
       [](int32_t a) { return 2 * a + 1; });
 
-  std::vector<int32_t> test_values = compiler::ValueHelper::int32_vector();
-  for (int32_t v : test_values) tester.CheckCall(v);
+  FOR_INT32_INPUTS(v) { tester.CheckCall(*v); }
 }
 
 // Pass int64_t, return double.
@@ -111,10 +110,7 @@ TEST(TestCWasmEntryArgPassing_double_int64) {
        WASM_F64_SCONVERT_I64(WASM_GET_LOCAL(0))},
       [](int64_t a) { return static_cast<double>(a); });
 
-  std::vector<int64_t> test_values_i64 = compiler::ValueHelper::int64_vector();
-  for (int64_t v : test_values_i64) {
-    tester.CheckCall(v);
-  }
+  FOR_INT64_INPUTS(v) { tester.CheckCall(*v); }
 }
 
 // Pass double, return int64_t.
@@ -124,9 +120,7 @@ TEST(TestCWasmEntryArgPassing_int64_double) {
        WASM_I64_SCONVERT_F64(WASM_GET_LOCAL(0))},
       [](double d) { return static_cast<int64_t>(d); });
 
-  for (int64_t i : compiler::ValueHelper::int64_vector()) {
-    tester.CheckCall(i);
-  }
+  FOR_INT64_INPUTS(i) { tester.CheckCall(*i); }
 }
 
 // Pass float, return double.
@@ -138,8 +132,7 @@ TEST(TestCWasmEntryArgPassing_float_double) {
            WASM_F64(1))},
       [](float f) { return 2. * static_cast<double>(f) + 1.; });
 
-  std::vector<float> test_values = compiler::ValueHelper::float32_vector();
-  for (float f : test_values) tester.CheckCall(f);
+  FOR_FLOAT32_INPUTS(f) { tester.CheckCall(*f); }
 }
 
 // Pass two doubles, return double.
@@ -149,11 +142,8 @@ TEST(TestCWasmEntryArgPassing_double_double) {
        WASM_F64_ADD(WASM_GET_LOCAL(0), WASM_GET_LOCAL(1))},
       [](double a, double b) { return a + b; });
 
-  std::vector<double> test_values = compiler::ValueHelper::float64_vector();
-  for (double d1 : test_values) {
-    for (double d2 : test_values) {
-      tester.CheckCall(d1, d2);
-    }
+  FOR_FLOAT64_INPUTS(d1) {
+    FOR_FLOAT64_INPUTS(d2) { tester.CheckCall(*d1, *d2); }
   }
 }
 
@@ -176,10 +166,11 @@ TEST(TestCWasmEntryArgPassing_AllTypes) {
         return 0. + a + b + c + d;
       });
 
-  std::vector<int32_t> test_values_i32 = compiler::ValueHelper::int32_vector();
-  std::vector<int64_t> test_values_i64 = compiler::ValueHelper::int64_vector();
-  std::vector<float> test_values_f32 = compiler::ValueHelper::float32_vector();
-  std::vector<double> test_values_f64 = compiler::ValueHelper::float64_vector();
+  Vector<const int32_t> test_values_i32 = compiler::ValueHelper::int32_vector();
+  Vector<const int64_t> test_values_i64 = compiler::ValueHelper::int64_vector();
+  Vector<const float> test_values_f32 = compiler::ValueHelper::float32_vector();
+  Vector<const double> test_values_f64 =
+      compiler::ValueHelper::float64_vector();
   size_t max_len =
       std::max(std::max(test_values_i32.size(), test_values_i64.size()),
                std::max(test_values_f32.size(), test_values_f64.size()));

test/cctest/wasm/test-wasm-interpreter-entry.cc

@@ -101,8 +101,7 @@ TEST(TestArgumentPassing_int32) {
        WASM_GET_LOCAL(0), WASM_CALL_FUNCTION0(f2.function_index())},
       [](int32_t a) { return 2 * a + 1; });
 
-  std::vector<int32_t> test_values = compiler::ValueHelper::int32_vector();
-  for (int32_t v : test_values) helper.CheckCall(v);
+  FOR_INT32_INPUTS(v) { helper.CheckCall(*v); }
 }
 
 // Pass int64_t, return double.
@@ -125,17 +124,13 @@ TEST(TestArgumentPassing_double_int64) {
         return static_cast<double>(a64 | b64);
       });
 
-  std::vector<int32_t> test_values_i32 = compiler::ValueHelper::int32_vector();
-  for (int32_t v1 : test_values_i32) {
-    for (int32_t v2 : test_values_i32) {
-      helper.CheckCall(v1, v2);
-    }
+  FOR_INT32_INPUTS(v1) {
+    FOR_INT32_INPUTS(v2) { helper.CheckCall(*v1, *v2); }
   }
 
-  std::vector<int64_t> test_values_i64 = compiler::ValueHelper::int64_vector();
-  for (int64_t v : test_values_i64) {
-    int32_t v1 = static_cast<int32_t>(v);
-    int32_t v2 = static_cast<int32_t>(v >> 32);
+  FOR_INT64_INPUTS(v) {
+    int32_t v1 = static_cast<int32_t>(*v);
+    int32_t v2 = static_cast<int32_t>(*v >> 32);
     helper.CheckCall(v1, v2);
     helper.CheckCall(v2, v1);
   }
@@ -176,8 +171,7 @@ TEST(TestArgumentPassing_float_double) {
        WASM_GET_LOCAL(0), WASM_CALL_FUNCTION0(f2.function_index())},
       [](float f) { return 2. * static_cast<double>(f) + 1.; });
 
-  std::vector<float> test_values = compiler::ValueHelper::float32_vector();
-  for (float f : test_values) helper.CheckCall(f);
+  FOR_FLOAT32_INPUTS(f) { helper.CheckCall(*f); }
 }
 
 // Pass two doubles, return double.
@@ -193,11 +187,8 @@ TEST(TestArgumentPassing_double_double) {
                            WASM_CALL_FUNCTION0(f2.function_index())},
                           [](double a, double b) { return a + b; });
 
-  std::vector<double> test_values = compiler::ValueHelper::float64_vector();
-  for (double d1 : test_values) {
-    for (double d2 : test_values) {
-      helper.CheckCall(d1, d2);
-    }
+  FOR_FLOAT64_INPUTS(d1) {
+    FOR_FLOAT64_INPUTS(d2) { helper.CheckCall(*d1, *d2); }
   }
 }
 
@@ -242,10 +233,11 @@ TEST(TestArgumentPassing_AllTypes) {
     helper.CheckCall(a, b1, b0, c, d);
   };
 
-  std::vector<int32_t> test_values_i32 = compiler::ValueHelper::int32_vector();
-  std::vector<int64_t> test_values_i64 = compiler::ValueHelper::int64_vector();
-  std::vector<float> test_values_f32 = compiler::ValueHelper::float32_vector();
-  std::vector<double> test_values_f64 = compiler::ValueHelper::float64_vector();
+  Vector<const int32_t> test_values_i32 = compiler::ValueHelper::int32_vector();
+  Vector<const int64_t> test_values_i64 = compiler::ValueHelper::int64_vector();
+  Vector<const float> test_values_f32 = compiler::ValueHelper::float32_vector();
+  Vector<const double> test_values_f64 =
+      compiler::ValueHelper::float64_vector();
   size_t max_len =
       std::max(std::max(test_values_i32.size(), test_values_i64.size()),
                std::max(test_values_f32.size(), test_values_f64.size()));