jit

问题 Our web site has a fairly complex JS app that fails with the latest Firefox 10 release. This is due to what appears to be a bug in the JS interpretor, making variables return NULL when they clearly aren't. This bug only occurs when the JIT compiler is active, not when it's disabled. We will report the bug to Mozilla and try to find a workaround. Is there a way to disable the JIT in Firefox for a specific script, from inside the script? Thank you. 回答1: The answer comes from Brian Hackett (

问题 (I know this is probably a duplicate, but is it almost impossible to search this topic on Google or on SO.) I know the java.compiler system property can take " NONE " which disables the JIT compiler, but I am interested in what other values are there and what are their performance characteristics. 回答1: In the early days I believe it was intended that there be competition among external vendors to supply an external .dll/.so named by this property. symcjit.dll was the only one I ever

问题 I'm trying to craft a short C# snippet that would illustrate change of Assembly.GetCallingAssembly() behavior because of JIT-inlining outlined in MSDN. Here's my code so far: class Program { static void Main(string[] args) { Console.WriteLine( GetAssembly().FullName ); Console.ReadLine(); } static Assembly GetAssembly() { return System.Reflection.Assembly.GetCallingAssembly(); } } which I build in "Release" and start using "Start Without Debugging" - this setup made code from this answer

问题 Suppose I generate a C program during execution time: source = "int add_x_y(int x, int y){ return x + y; }"; source_size = 42; I want the following function: void* compile(char* source, int source_size); Such that: int (*f)(int,int) = compile(source, source_size); printf("%d\n",f(2,3)); Outputs: 5 And compile can't depend on external tools (compilers), as I'd like to use it in emscripten (which converts a C program to a .js file). Is that possible? 回答1: Someone else can probably fill in some

问题 Why is the "someValue" variable which is readonly (but we still can change its value via reflection) output as "10", although it actually did change to 55? static class Program { static readonly int someValue = 10; static void Main(string[] args) { Console.WriteLine(someValue); // 10 typeof(Program) .GetField("someValue", BindingFlags.Static | BindingFlags.NonPublic) .SetValue(null, 55); // change readonly field via reflection to 55 Console.WriteLine(someValue); // output in console 10, //

问题 The traditional answer to "why is Javascript slower than native code?" is: "Because it's interpreted". The problem with this claim is that interpretation is not a quality of the language itself. As a matter of fact, nowadays most Javascript code is being JITed, still, this isn't even close to native speed. What if we remove the interpretation factor from the equation and make Javascript AOT compiled? Will it then match the performance of native code? If yes, why isn't this widely done over

问题 So I wanted to speed up a program I wrote with the help of numba jit . However jit seems to be not compatible with many scipy functions because they use try ... except ... structures that jit cannot handle (Am I right with this point?) A relatively simple solution I came up with is to copy the scipy source code I need and delete the try except parts (I already know that it will not run into errors so the try part will always work anyways) However I do not like this solution and I am not sure

问题 I'm trying to understand how the @jitclass decorator works with nested classes. I have written two dummy classes: fifi and toto fifi has a toto attribute. Both classes have the @jitclass decorator but compilation fails. Here's the code: fifi.py from numba import jitclass, float64 from toto import toto spec = [('a',float64),('b',float64),('c',toto)] @jitclass(spec) class fifi(object): def __init__(self, combis): self.a = combis self.b = 2 self.c = toto(combis) def mySqrt(self,x): s = x for i

问题 I would like to know how to check if the JIT compiler is turned off. I have the following code which is meant to turn the JIT compiler off.The problem is, I am not sure if it is actually doing that. So I was wondering if there is a way of checking if the JIT is off. I looked at the Compiler class but there isn't any method like isDisabled/enabled() . Code: Compiler.disable(); Any help or direction will be highly appreciated. 回答1: I don't believe you can turn the JIT off at runtime. If you

问题 Microsoft recently released tools and documentation for its new Phone 7 platform, which to the dismay of those who have a big C++ codebase (like me) doesn't support native development anymore. Although I've found speculation about this decision being reversed, I doubt it. So I was thinking how viable would be to make this codebase available to Phone 7 by adapting it to compile under C++/CLI. Of course the user interface parts couldn't be ported, but I'm not sure about the rest. Anyone had a