node-murmurhash - npm Package Compare versions

Comparing version 2.0.1 to 2.1.0

History.md

 
+2.1.0 / 2015-11-26
+==================
+
+ * feat: use Math.imul (@alsotang)
+
 2.0.1 / 2015-07-21
@@ -3,0 +8,0 @@ ==================

lib/murmur.js

@@ -22,39 +22,19 @@ /**!
 
-// @zhangzifa: c语言中，大于127的char, 在转成 int 时, 表示成0xffffffxx的形式
-var NEGTIVE_MAP = [
-  0x0,  0x1,  0x2,  0x3,  0x4,  0x5,  0x6,  0x7,  0x8,  0x9,  0xa,  0xb,
-  0xc,  0xd,  0xe,  0xf,  0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
-  0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
-  0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
-  0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
-  0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
-  0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53,
-  0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
-  0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b,
-  0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
-  0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
-  0xffffff80, 0xffffff81, 0xffffff82, 0xffffff83, 0xffffff84, 0xffffff85,
-  0xffffff86, 0xffffff87, 0xffffff88, 0xffffff89, 0xffffff8a, 0xffffff8b,
-  0xffffff8c, 0xffffff8d, 0xffffff8e, 0xffffff8f, 0xffffff90, 0xffffff91,
-  0xffffff92, 0xffffff93, 0xffffff94, 0xffffff95, 0xffffff96, 0xffffff97,
-  0xffffff98, 0xffffff99, 0xffffff9a, 0xffffff9b, 0xffffff9c, 0xffffff9d,
-  0xffffff9e, 0xffffff9f, 0xffffffa0, 0xffffffa1, 0xffffffa2, 0xffffffa3,
-  0xffffffa4, 0xffffffa5, 0xffffffa6, 0xffffffa7, 0xffffffa8, 0xffffffa9,
-  0xffffffaa, 0xffffffab, 0xffffffac, 0xffffffad, 0xffffffae, 0xffffffaf,
-  0xffffffb0, 0xffffffb1, 0xffffffb2, 0xffffffb3, 0xffffffb4, 0xffffffb5,
-  0xffffffb6, 0xffffffb7, 0xffffffb8, 0xffffffb9, 0xffffffba, 0xffffffbb,
-  0xffffffbc, 0xffffffbd, 0xffffffbe, 0xffffffbf, 0xffffffc0, 0xffffffc1,
-  0xffffffc2, 0xffffffc3, 0xffffffc4, 0xffffffc5, 0xffffffc6, 0xffffffc7,
-  0xffffffc8, 0xffffffc9, 0xffffffca, 0xffffffcb, 0xffffffcc, 0xffffffcd,
-  0xffffffce, 0xffffffcf, 0xffffffd0, 0xffffffd1, 0xffffffd2, 0xffffffd3,
-  0xffffffd4, 0xffffffd5, 0xffffffd6, 0xffffffd7, 0xffffffd8, 0xffffffd9,
-  0xffffffda, 0xffffffdb, 0xffffffdc, 0xffffffdd, 0xffffffde, 0xffffffdf,
-  0xffffffe0, 0xffffffe1, 0xffffffe2, 0xffffffe3, 0xffffffe4, 0xffffffe5,
-  0xffffffe6, 0xffffffe7, 0xffffffe8, 0xffffffe9, 0xffffffea, 0xffffffeb,
-  0xffffffec, 0xffffffed, 0xffffffee, 0xffffffef, 0xfffffff0, 0xfffffff1,
-  0xfffffff2, 0xfffffff3, 0xfffffff4, 0xfffffff5, 0xfffffff6, 0xfffffff7,
-  0xfffffff8, 0xfffffff9, 0xfffffffa, 0xfffffffb, 0xfffffffc, 0xfffffffd,
-  0xfffffffe, 0xffffffff
-];
+function negative(num) {
+  if (num < 127) {
+    return num;
+  }
+  return num | 0xffffff00
+}
 
+var imul = (function () {
+  if (Math.imul) {
+    return Math.imul;
+  } else {
+    return function (a, b) {
+      return ((((a >> 16) * b) & 0xffff) << 16) + ((a & 0xffff) * b)
+    }
+  }
+})()
+
 function murmurhash2js(key, seed) {
@@ -74,8 +54,8 @@ var l = key.length;
     // 此处两个 32 位整数相乘时，有可能产生 64 位的结果，导致精度丢失。
-    k = (((k & 0xffff) * MURMURHASH_M) + ((((k >>> 16) * MURMURHASH_M) & 0xffff) << 16));
+    k = imul(k, MURMURHASH_M)
 
     k ^= k >>> 24;
-    k = (((k & 0xffff) * MURMURHASH_M) + ((((k >>> 16) * MURMURHASH_M) & 0xffff) << 16));
+    k = imul(k, MURMURHASH_M)
 
-    h = (((h & 0xffff) * MURMURHASH_M) + ((((h >>> 16) * MURMURHASH_M) & 0xffff) << 16)) ^ k;
+    h = imul(h, MURMURHASH_M) ^ k
 
@@ -88,12 +68,12 @@ l -= 4;
     case 3:
-      h ^= NEGTIVE_MAP[key[i + 2]] << 16;
+      h ^= negative(key[i + 2]) << 16;
     case 2:
-      h ^= NEGTIVE_MAP[key[i + 1]] << 8;
+      h ^= negative(key[i + 1]) << 8;
     case 1:
-      h ^= NEGTIVE_MAP[key[i]];
-      h = (((h & 0xffff) * MURMURHASH_M) + ((((h >>> 16) * MURMURHASH_M) & 0xffff) << 16));
+      h ^= negative(key[i]);
+      h = imul(h, MURMURHASH_M)
   }
 
   h ^= h >>> 13;
-  h = (((h & 0xffff) * MURMURHASH_M) + ((((h >>> 16) * MURMURHASH_M) & 0xffff) << 16));
+  h = imul(h, MURMURHASH_M)
   h ^= h >>> 15;
@@ -100,0 +80,0 @@

lib/murmurhash.js

@@ -17,2 +17,3 @@ /**!
 
+
 /**
@@ -19,0 +20,0 @@ * Murmur hash v2

package.json

 {
   "name": "node-murmurhash",
-  "version": "2.0.1",
+  "version": "2.1.0",
   "description": "murmurhash V2, support utf8 Buffer",
@@ -5,0 +5,0 @@ "main": "lib/murmurhash.js",

README.md

@@ -46,12 +46,11 @@ node-murmurhash
 ```
-cpu: 1.4 GHz Intel Core i5
-node version: v2.3.0, date: Tue Jul 21 2015 17:35:09 GMT+0800 (CST)
+node version: v4.2.1, date: Sun Nov 15 2015 01:01:49 GMT+0800 (CST)
 Starting...
 2 tests completed.
 
-murmurhash(new Buffer('haha, this is key')) x 6,626,182 ops/sec ±1.89% (80 runs sampled)
-murmurhash(new Buffer('hello 中国'))          x 8,510,543 ops/sec ±2.24% (80 runs sampled)
+murmurhash(new Buffer(ascii)) x 21,164,676 ops/sec ±0.85% (98 runs sampled)
+murmurhash(new Buffer(utf8))  x 13,926,544 ops/sec ±0.59% (99 runs sampled)
 ```
 
-see also: [benchmark.md](benchmark.md)
+see also: [benchmark](test/benchmark.js)
 
@@ -58,0 +57,0 @@ ## License

No alert changes

Worsened metrics

Total package byte prevSize

7766

-24.27%

Lines of code

96

-17.95%

Number of lines in readme file

59

-1.67%

No dependency changes