pnkfelix

FILE: liquid-resize-norrowed.js

// -*- mode: js2; indent-tabs-mode: nil; -*-

var baz = new Array(100);
function F() { }
baz.__proto__ = new F(); // <-- need this to expose issue

for (var i=0; i < 99; i++) {
//              ^-- this threshold needs to be high to expose issue

pnkfelix

18-56-51 src/parjs-benchmarks (git:(no branch)) % git diff
diff --git a/js/src/jsmath.cpp b/js/src/jsmath.cpp
index b166722..0ad677d 100644
--- a/js/src/jsmath.cpp
+++ b/js/src/jsmath.cpp
@@ -96,6 +96,18 @@ js_math_abs(JSContext *cx, unsigned argc, Value *vp)
 {
     double x, z;
 
+#ifdef DEBUG

pnkfelix

% cat math/mat.rs
pub struct Mat4<T> { x:T }
% cat main.rs
// // Don't do this:
// use math::mat::*;
// // Do this:
mod math { mod mat; }


fn main() {

pnkfelix

% git diff
diff --git a/js/src/parjs-benchmarks/nbody.js b/js/src/parjs-benchmarks/nbody.js
index 1a0195e..9055381 100644
--- a/js/src/parjs-benchmarks/nbody.js
+++ b/js/src/parjs-benchmarks/nbody.js
@@ -474,6 +474,22 @@ function emulateNBody(mode, numBodies, ticks) {
 const NUMBODIES = 4000;
 const TICKS = 10;
 
-benchmark("NBODY", 1, DEFAULT_MEASURE,

pnkfelix

(gdb) r -e 'var libdir="../js/src/parjs-benchmarks/"; var MODE="compare";' ../js/src/parjs-benchmarks/nbody.js
Starting program: /Users/fklock/Dev/Mozilla/iontrail/objdir-dbg-js/js -e 'var libdir="../js/src/parjs-benchmarks/"; var MODE="compare";' ../js/src/parjs-benchmarks/nbody.js
BFD: /System/Library/Frameworks/CFNetwork.framework/Versions/A/CFNetwork(i386:x86-64): unknown load command 0x20
Warming up sequential runs
.
Measuring sequential runs
Measuring parallel runs
Assertion failure: hasParallelIonScript(), at /Users/fklock/Dev/Mozilla/iontrail/js/src/jsscript.h:621
[New Thread 0x1f03 of process 71782]
[New Thread 0x2003 of process 71782]

pnkfelix

Driving Code (put at bottom of nbody.js):
-----------------------------------------
for (var k=1; k < 9; k++) {
  benchmark("NBODY_"+k+"K", 1, DEFAULT_MEASURE,
            function () { emulateNBody("seq", k*1000, TICKS); },
            function () { emulateNBody("par", k*1000, TICKS); });

  benchmark("NBODY_"+k+".5K", 1, DEFAULT_MEASURE,
            function () { emulateNBody("seq", k*1000+500, TICKS); },
            function () { emulateNBody("par", k*1000+500, TICKS); });

pnkfelix

OVERVIEW
--------

I grabbed http://davidbau.com/encode/seedrandom.js and threw it into parjs-benchmarks.  (Can we just add it?  Its license looks like it is likely to be compatible, but IANAL.)  Then I loaded the file, and changed `emulateNBody` to set the seed before each run:

Here's the description of the concrete changes I made to use the seed and iterate on various workloads.

% diff --git a/js/src/parjs-benchmarks/nbody.js b/js/src/parjs-benchmarks/nbody.js
index 1a0195e..aba2cef 100644
--- a/js/src/parjs-benchmarks/nbody.js

pnkfelix

Top-most portion of backtrace:

#0  js::ion::CodeLocationJump::raw (this=0x7fff5fbd0890) at Assembler-shared.h:444
#1  0x00000001009ea082 in js::ion::PatchJump (jump={raw_ = 0xdeadc0de <Address 0xdeadc0de out of bounds>, absolute_ = true, jumpTableEntry_ = 0xdeadab1e <Address 0xdeadab1e out of bounds>}, label={raw_ = 0x106eee0f6 "<felix-deleted-non-utf8-garbage-in-string>", absolute_ = true}) at Assembler-x64.h:600
#2  0x00000001009e8909 in js::ion::IonCache::reset (this=0x104034698) at /Users/fklock/Dev/Mozilla/iontrail/js/src/ion/IonCaches.cpp:1359
#3  0x00000001009e886f in js::ion::ParallelGetPropertyIC::reset (this=0x104034698) at /Users/fklock/Dev/Mozilla/iontrail/js/src/ion/IonCaches.cpp:1145
#4  0x0000000100947f34 in js::ion::IonScript::purgeCaches (this=0x104034600, c=0x10289dc00) at /Users/fklock/Dev/Mozilla/iontrail/js/src/ion/Ion.cpp:801


Scroll down to bottom to see full backtrace.  Something is wrong and niko said it is in code that shu recently touched.  Unfortunately it takes a long time for t

pnkfelix

(gdb) pwd
Working directory /Users/fklock/Dev/Mozilla/iontrail/objdir-dbg-js.
(gdb) cd /Users/fklock/Dev/Mozilla/iontrail/js/src/parjs-benchmarks
Working directory /Users/fklock/Dev/Mozilla/iontrail/js/src/parjs-benchmarks.
(gdb) r -e 'var libdir="./"; var MODE="compare";' nbody-fail.js
Starting program: /Users/fklock/Dev/Mozilla/iontrail/objdir-dbg-js/js -e 'var libdir="./"; var MODE="compare";' nbody-fail.js
Reading symbols for shared libraries ++++++++.............................................................. done
Warming up sequential runs
.
Measuring sequential runs

pnkfelix

fn vec_peek<T>(v: &'r [T]) -> Option< (&'r T, &'r [T]) > {
    if v.len() == 0 {
        None
    } else {
        let head = &v[0];
        let tail = v.view(1, v.len());
        Some( (head, tail) )
    }
}