expose counter in d8

test/mjsunit/d8-counter.js

Index: test/mjsunit/d8-counter.js
diff --git a/test/mjsunit/d8-counter.js b/test/mjsunit/d8-counter.js
new file mode 100644
index 0000000000000000000000000000000000000000..10113cfc97af3acbd56d6c633700df208a78d2a8
--- /dev/null
+++ b/test/mjsunit/d8-counter.js
@@ -0,0 +1,66 @@
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Test the counter module of d8. Work in progress.
+
+function round(number, digits) {
+  var multiplier = Math.pow(10, digits);
+  return Math.round(number*multiplier) / multiplier;
+}
+
+print("compiled code size: " + counter.get("c:V8.TotalCompiledCodeSize"));
+
+// Test whether all counters have been initialized
+assertEquals(173, counter.names().length);
+
+// Two input files were parsed and compiled
+assertEquals(2, counter.get("V8.Parse"));
+
+// Test math stuff
+// Integral of sin^2(x) from 0 to pi is pi/2
+var sum = 0;
+var segments = 1000;
+var delta = (Math.PI/segments);
+for(var i = 0; i < segments; i++) {
+  var x = i/segments * Math.PI;
+  sum += Math.sin(x) * delta;
+  assertEquals(round(Math.tan(x), 7), round(Math.sin(x)/Math.cos(x), 7));
+}
+
+assertEquals(round(2, 5), round(sum, 5));
+
+print("number of transcendental cache misses for Math.sin: "
+      + counter.get("c:V8.MathSin"));
+print("number of transcendental cache misses for Math.cos: "
+      + counter.get("c:V8.MathCos"));
+print("number of transcendental cache misses for Math.tan: "
+      + counter.get("c:V8.MathTan"));
+

[Yang, 2011/06/29 12:02:20]

surprisingly, c:V8.MathSin and c:V8.MathCos both receive the value 1, while
c:V8.MathTan ends up with 1000... no caching involved here?

+print("total transcendental cache misses: "
+      + counter.get("c:V8.TranscendentalCacheMiss"));
+
+print("compiled code size: " + counter.get("c:V8.TotalCompiledCodeSize"));