JS: use optimized emulation of int32 multiplication. Add test for emulated int32 multiplication

2016-12-20 12:50:37 +03:00
parent 7d8df5c81c
commit d3d406356c
3 changed files with 45 additions and 7 deletions
@@ -0,0 +1,32 @@
+fun imul32(a: Int, b: Int): Int = js("Kotlin").imulEmulated(a, b)
+
+fun imul64(a: Int, b: Int): Int = (a.toLong() * b.toLong()).toInt()
+
+fun generateSeries(data: List<Int>): List<Pair<Int, Int>> {
+    val result = mutableListOf<Pair<Int, Int>>()
+    for (i in data.indices) {
+        for (j in i..data.lastIndex) {
+            result += Pair(data[i], data[j])
+        }
+    }
+    return result
+}
+
+fun test(series: List<Pair<Int, Int>>): String? {
+    for ((a, b) in series) {
+        (testSingle(a, b) ?: testSingle(a, -b) ?: testSingle(-a, b) ?: testSingle(-a, -b))?.let { return it }
+    }
+    return null
+}
+
+fun testSingle(a: Int, b: Int): String? {
+    var actual = imul32(a, b)
+    var expected = imul64(a, b)
+    return if (actual != expected) "$a * $b = $expected, got $actual" else null
+}
+
+fun box(): String {
+    val error = test(generateSeries(listOf(3, 0x1234, 0xFFFF, 0xABCD, 0xABCDEF, 0x43211234, 0x7FFFFFFC, 0x7FFFFFFF)))
+    if (error != null) return "fail: error"
+    return "OK"
+}