[builtins] implement JSBuiltinReducer for ArrayIteratorNext()

test/mjsunit/es6/array-iterator-turbo.js

+// 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.
+
+// Flags: --turbo --turbo-escape --allow-natives-syntax
+
+"use strict";
+
+const kDeoptimized = 2;
+const kTurbofanned = 7;
+let global = this;
+let tests = {
+  FastElementsKind() {
+    let runners = {
+      FAST_SMI_ELEMENTS(array) {
+        let sum = 0;
+        for (let x of array) sum += x;
+        return sum;
+      },
+
+      FAST_HOLEY_SMI_ELEMENTS(array) {
+        let sum = 0;
+        for (let x of array) {
+          if (x) sum += x;
+        }
+        return sum;
+      },
+
+      FAST_ELEMENTS(array) {
+        let ret = "";
+        for (let str of array) ret += `> ${str}`;
+        return ret;
+      },
+
+      FAST_HOLEY_ELEMENTS(array) {
+        let ret = "";
+        for (let str of array) ret += `> ${str}`;
+        return ret;
+      },
+
+      FAST_DOUBLE_ELEMENTS(array) {
+        let sum = 0.0;
+        for (let x of array) sum += x;
+          return sum;
+      },
+
+      FAST_HOLEY_DOUBLE_ELEMENTS(array) {
+        let sum = 0.0;
+        for (let x of array) {
+          if (x) sum += x;
+        }
+        return sum;
+      }
+    };
+
+    let tests = {
+      FAST_SMI_ELEMENTS: {
+        array: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
+        expected: 55,
+        array2: [1, 2, 3],
+        expected2: 6
+      },
+      FAST_HOLEY_SMI_ELEMENTS: {
+        array: [1, , 3, , 5, , 7, , 9, ,],
+        expected: 25,
+        array2: [1, , 3],
+        expected2: 4
+      },
+      FAST_ELEMENTS: {
+        array: ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j"],
+        expected: "> a> b> c> d> e> f> g> h> i> j",
+        array2: ["a", "b", "c"],
+        expected2: "> a> b> c"
+      },
+      FAST_HOLEY_ELEMENTS: {
+        array: ["a", , "c", , "e", , "g", , "i", ,],
+        expected: "> a> undefined> c> undefined> e> undefined> g" +
+                  "> undefined> i> undefined",
+        array2: ["a", , "c"],
+        expected2: "> a> undefined> c"
+      },
+      FAST_DOUBLE_ELEMENTS: {
+        array: [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0],
+        expected: 5.5,
+        array2: [0.6, 0.4, 0.2],
+        expected2: 1.2
+      },
+      FAST_HOLEY_DOUBLE_ELEMENTS: {
+        array: [0.1, , 0.3, , 0.5, , 0.7, , 0.9, ,],
+        expected: 2.5,
+        array2: [0.1, , 0.3],
+        expected2: 0.4
+      }
+    };
+
+    for (let key of Object.keys(runners)) {
+      let fn = runners[key];
+      let { array, expected, array2, expected2 } = tests[key];
+
+      // Warmup:
+      fn(array);
+      fn(array);
+      %OptimizeFunctionOnNextCall(fn);
+      fn(array);
+
+      // TODO(bmeurer): FAST_HOLEY_DOUBLE_ELEMENTS maps generally deopt when
+      // a hole is encountered. Test should be fixed once that is corrected.
+      let status = /HOLEY_DOUBLE/.test(key) ? kDeoptimized : kTurbofanned;
+
+      assertEquals(status, %GetOptimizationStatus(fn), key);
+      assertEquals(expected, fn(array), key);
+      assertEquals(status, %GetOptimizationStatus(fn), key);
+
+      // Check no deopt when another arra with the same map is used
+      assertTrue(%HaveSameMap(array, array2), key);
+      assertEquals(status, %GetOptimizationStatus(fn), key);
+      assertEquals(expected2, fn(array2), key);
+
+      // CheckMaps bailout
+      let newArray = Object.defineProperty(
+          [1, 2, 3], 2, { enumerable: false, configurable: false,
+                          get() { return 7; } });
+      fn(newArray);
+      assertEquals(kDeoptimized, %GetOptimizationStatus(fn), key);
+    }
+  },
+
+  TypedArrays() {
+    let tests = {
+      Uint8Array: {
+        array: new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8, -1, 256]),
+        expected: 291,
+        array2: new Uint8Array([1, 2, 3]),
+        expected2: 6
+      },
+
+      Int8Array: {
+        array: new Int8Array([1, 2, 3, 4, 5, 6, 7, 8, -129, 128]),
+        expected: 35,
+        array2: new Int8Array([1, 2, 3]),
+        expected2: 6
+      },
+
+      Uint16Array: {
+        array: new Uint16Array([1, 2, 3, 4, 5, 6, 7, 8, -1, 0x10000]),
+        expected: 65571,
+        array2: new Uint16Array([1, 2, 3]),
+        expected2: 6
+      },
+
+      Int16Array: {
+        array: new Int16Array([1, 2, 3, 4, 5, 6, 7, 8, -32769, 0x7FFF]),
+        expected: 65570,
+        array2: new Int16Array([1, 2, 3]),
+        expected2: 6
+      },
+
+      Uint32Array: {
+        array: new Uint32Array([1, 2, 3, 4, 5, 6, 7, 8, -1, 0x100000000]),
+        expected: 4294967331,
+        array2: new Uint32Array([1, 2, 3]),
+        expected2: 6
+      },
+
+      Int32Array: {
+        array: new Int32Array([1, 2, 3, 4, 5, 6, 7, 8,
+                               -2147483649, 0x7FFFFFFF]),
+        expected: 4294967330,
+        array2: new Int32Array([1, 2, 3]),
+        expected2: 6
+      },
+
+      Float32Array: {
+        array: new Float32Array([9.5, 8.0, 7.0, 7.0, 5.0, 4.0, 3.0, 2.0]),
+        expected: 45.5,
+        array2: new Float32Array([10.5, 5.5, 1.5]),
+        expected2: 17.5
+      },
+
+      Float64Array: {
+        array: new Float64Array([9.5, 8.0, 7.0, 7.0, 5.0, 4.0, 3.0, 2.0]),
+        expected: 45.5,
+        array2: new Float64Array([10.5, 5.5, 1.5]),
+        expected2: 17.5
+      },
+
+      Uint8ClampedArray: {
+        array: new Uint8ClampedArray([4.3, 7.45632, 3.14, 4.61, 5.0004, 6.493,
+                                      7.12, 8, 1.7, 3.6]),
+        expected: 51,
+        array2: new Uint8ClampedArray([1, 2, 3]),
+        expected2: 6
+      }
+    };
+
+    for (let key of Object.keys(tests)) {
+      let test = tests[key];
+      let { array, expected, array2, expected2 } = test;
+
+      let sum = function(array) {
+        let ret = 0;
+        for (let x of array) ret += x;
+        return ret;
+      };
+
+      // Warmup
+      sum(array);
+      sum(array);
+      %OptimizeFunctionOnNextCall(sum);
+      assertEquals(expected, sum(array), key);
+
+      assertEquals(kTurbofanned, %GetOptimizationStatus(sum), key);
+
+      // Not deoptimized when called on typed array of same type / map
+      assertTrue(%HaveSameMap(array, array2));
+      assertEquals(expected2, sum(array2), key);
+      assertEquals(kTurbofanned, %GetOptimizationStatus(sum), key);
+
+      // Throw when detached
+      let clone = new array.constructor(array);
+      %ArrayBufferNeuter(clone.buffer);
+      assertThrows(() => sum(clone), TypeError);

[caitp, 2016/11/10 20:27:41]

for example (of not being able to test bailouts in JS code), this test passes,
but `sum` is still turbofan code. So,this means the baseline path must be taken,
but what I would expect is that the iterator constructor is inlined in
turbofanned `sum`(), which should lead to a bailout.

I expect I'd put tests for these in cctest/compiler/test-inlining.cc, but there
doesn't seem to be a lot of precedent for those sorts of tests there.

+    }
+  }
+};
+
+for (let name of Object.keys(tests)) {
+  let test = tests[name];
+  test();
+}