Add non-COW inputs to Array.from benchmarks.

This makes clear that some benchmarks where Array.from is used to
clone the array are very fast because the array is COW, and the
added benchmarks for non-COW arrays are not as fast. COW-ness does
not affect benchmarks where Array.from is called with a callback
function.

Change-Id: Ie9dd5507df5dd7501ac955dba4d3682c4a54548e
Reviewed-on: https://chromium-review.googlesource.com/c/1314333Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Hai Dang <dhai@google.com>
Cr-Commit-Position: refs/heads/master@{#57208}

test/js-perf-test/Array/from.js

@@ -4,10 +4,15 @@
 (() => {
 
   createSuite('MixedFrom', 1000, MixedFrom, MixedFromSetup);
-  createSuite('MixedNoMapFrom', 1000, MixedNoMapFrom, MixedNoMapFromSetup);
+  createSuite(
+      'MixedCowNoMapFrom', 1000, MixedCowNoMapFrom, MixedCowNoMapFromSetup);
+  createSuite('MixedNonCowNoMapFrom', 1000, MixedNonCowNoMapFrom,
+              MixedNonCowNoMapFromSetup);
   createSuite('SmiFrom', 1000, SmiFrom, SmiFromSetup);
   createSuite('SmallSmiFrom', 1000, SmallSmiFrom, SmallSmiFromSetup);
-  createSuite('SmiNoMapFrom', 1000, SmiNoMapFrom, SmiNoMapFromSetup);
+  createSuite('SmiCowNoMapFrom', 1000, SmiCowNoMapFrom, SmiCowNoMapFromSetup);
+  createSuite(
+      'SmiNonCowNoMapFrom', 1000, SmiNonCowNoMapFrom, SmiNonCowNoMapFromSetup);
   createSuite(
       'SmiNoIteratorFrom', 1000, SmiNoIteratorFrom, SmiNoIteratorFromSetup);
   createSuite(
@@ -15,7 +20,10 @@
   createSuite('DoubleFrom', 1000, DoubleFrom, DoubleFromSetup);
   createSuite('DoubleNoMapFrom', 1000, DoubleNoMapFrom, DoubleNoMapFromSetup);
   createSuite('StringFrom', 1000, StringFrom, StringFromSetup);
-  createSuite('StringNoMapFrom', 1000, StringNoMapFrom, StringNoMapFromSetup);
+  createSuite(
+      'StringCowNoMapFrom', 1000, StringCowNoMapFrom, StringCowNoMapFromSetup);
+  createSuite('StringNonCowNoMapFrom', 1000, StringNonCowNoMapFrom,
+              StringNonCowNoMapFromSetup);
 
   function ArrayLike() {}
   ArrayLike.from = Array.from;
@@ -24,7 +32,9 @@
   var result;
   var func
 
-  var smi_array = [
+  // This creates a COW array of smis. COWness does not affect the performance
+  // of Array.from calls with a callback function.
+  var smi_array_Cow = [
     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
@@ -32,6 +42,11 @@
     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
   ];
 
+  // This creates a non-COW array.
+  var smi_array = Array.from(smi_array_Cow);
+  smi_array[0] = 1;
+
+  // This creates an array of doubles. There is no COW array for doubles.
   var double_array = [
     1.5,  2.5,  3.5,  4.5,  5.5,  6.5,  7.5,  8.5,  9.5,  10.5,  //
     11.5, 12.5, 13.5, 14.5, 15.5, 16.5, 17.5, 18.5, 19.5, 20.5,
@@ -45,7 +60,8 @@
     11.5, 12.5, 13.5, 14.5, 15.5, 16.5, 17.5, 18.5, 19.5, 20.5,
   ];
 
-  var string_array = [
+  // This creates a COW array of objects.
+  var string_array_Cow = [
     'a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c', 'a', 'a', 'b', 'c', 'a', 'b',
     'c', 'a', 'b', 'c', 'a', 'a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c', 'a',
     'a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c', 'a', 'a', 'b', 'c', 'a', 'b',
@@ -55,7 +71,12 @@
     'a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c', 'a',
   ];
 
-  var mixed_array = [
+  // This creates a non-COW array.
+  var string_array = Array.from(string_array_Cow);
+  string_array[0] = 'a';
+
+  // This creates a COW array of objects.
+  var mixed_array_Cow = [
     1,    2,    3,    4,    5,    6,    7,    8,    9,    10,
     11,   12,   13,   14,   15,   16,   17,   18,   19,   20,  //
     1,    2,    3,    4,    5,    6,    7,    8,    9,    10,
@@ -68,13 +89,21 @@
     'a',  'b',  'c',  'a',  'b',  'c',  'a',  'b',  'c',  'a',
   ];
 
+  // This creates a non-COW array.
+  var mixed_array = Array.from(mixed_array_Cow);
+  mixed_array[0] = 1;
+
   // Although these functions have the same code, they are separated for
   // clean IC feedback.
   function SmallSmiFrom() {
     result = Array.from(arg, func);
   }
 
-  function SmiNoMapFrom() {
+  function SmiCowNoMapFrom() {
+    result = Array.from(arg);
+  }
+
+  function SmiNonCowNoMapFrom() {
     result = Array.from(arg);
   }
 
@@ -102,7 +131,11 @@
     result = Array.from(arg, func);
   }
 
-  function StringNoMapFrom() {
+  function StringCowNoMapFrom() {
+    result = Array.from(arg);
+  }
+
+  function StringNonCowNoMapFrom() {
     result = Array.from(arg);
   }
 
@@ -110,7 +143,11 @@
     result = Array.from(arg, func);
   }
 
-  function MixedNoMapFrom() {
+  function MixedCowNoMapFrom() {
+    result = Array.from(arg);
+  }
+
+  function MixedNonCowNoMapFrom() {
     result = Array.from(arg);
   }
 
@@ -119,26 +156,31 @@
     arg = [1, 2, 3];
   }
 
-  function SmiNoMapFromSetup() {
+  function SmiCowNoMapFromSetup() {
+    func = undefined;
+    arg = smi_array_Cow;
+  }
+
+  function SmiNonCowNoMapFromSetup() {
     func = undefined;
     arg = smi_array;
   }
 
   function SmiFromSetup() {
     func = (v, i) => v + i;
-    arg = smi_array;
+    arg = smi_array_Cow;
   }
 
   function SmiNoIteratorFromSetup() {
     func = (v, i) => v + i;
-    array = smi_array;
+    array = smi_array_Cow;
     arg = {length: array.length};
     Object.assign(arg, array);
   }
 
   function TransplantedFromSetup() {
     func = (v, i) => v + i;
-    arg = smi_array;
+    arg = smi_array_Cow;
   }
 
   function DoubleFromSetup() {
@@ -153,20 +195,30 @@
 
   function StringFromSetup() {
     func = (v, i) => v + i;
-    arg = string_array;
+    arg = string_array_Cow;
   }
 
-  function StringNoMapFromSetup() {
+  function StringCowNoMapFromSetup() {
+    func = undefined;
+    arg = string_array_Cow;
+  }
+
+  function StringNonCowNoMapFromSetup() {
     func = undefined;
     arg = string_array;
   }
 
   function MixedFromSetup() {
     func = (v, i) => v + i;
-    arg = mixed_array;
+    arg = mixed_array_Cow;
+  }
+
+  function MixedCowNoMapFromSetup() {
+    func = undefined;
+    arg = mixed_array_Cow;
   }
 
-  function MixedNoMapFromSetup() {
+  function MixedNonCowNoMapFromSetup() {
     func = undefined;
     arg = mixed_array;
   }

test/js-perf-test/JSTests.json

@@ -887,15 +887,18 @@
         {"name": "SmallMixedArrayOf"},
         {"name": "SmiFrom"},
         {"name": "SmallSmiFrom"},
-        {"name": "SmiNoMapFrom"},
+        {"name": "SmiCowNoMapFrom"},
+        {"name": "SmiNonCowNoMapFrom"},
         {"name": "SmiNoIteratorFrom"},
         {"name": "TransplantedFrom"},
         {"name": "DoubleFrom"},
         {"name": "DoubleNoMapFrom"},
         {"name": "StringFrom"},
-        {"name": "StringNoMapFrom"},
+        {"name": "StringCowNoMapFrom"},
+        {"name": "StringNonCowNoMapFrom"},
         {"name": "MixedFrom"},
-        {"name": "MixedNoMapFrom"},
+        {"name": "MixedCowNoMapFrom"},
+        {"name": "MixedNonCowNoMapFrom"},
         {"name": "Array.slice(500)"},
         {"name": "Array.slice(500,999)"},
         {"name": "Array.slice(-500)"},