Tracing JITs and Modern CPUs: Part 2
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Tracing JITs and Modern CPUs: Part 2
1–10 of 21 posts
Re: Tracing JITs and Modern CPUs: Part 2
#2Is it a thing to blog with github issues now?
Re: Tracing JITs and Modern CPUs: Part 2
#3(Seems like an "embarrassingly serial" problem -- a smarter lua could turn it into a single "set c = 1e9" instruction.)
Re: Tracing JITs and Modern CPUs: Part 2
#4(Seems like an "embarrassingly serial" problem -- a smarter lua could turn it into a single "set c = 1e9" instruction.)
It could, but then we're getting into hairy language definition issues: Does Lua specify at what point updates need to hit memory? And this example is perfect example of why a language ought to be explicit about such guarantees - in this case such a change would have observable effects. Changing observable effects in optimizations is dangerous territory even when it's well defined.
Re: Tracing JITs and Modern CPUs: Part 2
#5Is it a thing to blog with github issues now?
In theory blogging on github issues could actually be quite convenient.
- Great(==standardized) markdown support.
- Easy image support.
- Uptime is someone else's problem.
- Sending someone your blog also directly links them to your ~entire public codebase.
- Builtin sane commenting system.
- Can keep code beside the blog. Its aggravating to find a living blog that links to a dead code host.
- Free with zero setup cost for everything above.
- Not having to deal with ruby dependencies for jekyll...
Edit: You know, I think I'm going to host my blog in this manner. When writing the above list I realized I'm sick of having to handle each of those.
Re: Tracing JITs and Modern CPUs: Part 2
#6(Seems like an "embarrassingly serial" problem -- a smarter lua could turn it into a single "set c = 1e9" instruction.)
It could, but then we're getting into hairy language definition issues: Does Lua specify at what point updates need to hit memory? And this example is perfect example of why a language ought to be explicit about such guarantees - in this case such a change would have observable effects. Changing observable effects in optimizations is dangerous territory even when it's well defined.
What's memory?
Lua's much more high level than that, and it makes no promises about timing at all.
Re: Tracing JITs and Modern CPUs: Part 2
#7Is it a thing to blog with github issues now?
In theory blogging on github issues could actually be quite convenient. - Great(==standardized) markdown support. - Easy image support. - Uptime is someone else's problem. - Sending someone your blog also directly links them to your ~entire public codebase. - Builtin sane commenting system. - Can keep code beside the blog. Its aggravating to find a living blog that links to a dead code host. - Free with zero setup co…
All of that works with hosting md files in github repo or in gists, but with them you also get a convenient version control system also known as git.
Re: Tracing JITs and Modern CPUs: Part 2
#8Earlier quoted context omitted.
It could, but then we're getting into hairy language definition issues: Does Lua specify at what point updates need to hit memory? And this example is perfect example of why a language ought to be explicit about such guarantees - in this case such a change would have observable effects. Changing observable effects in optimizations is dangerous territory even when it's well defined.
What's memory? Lua's much more high level than that, and it makes no promises about timing at all.
That has nothing to do with high level, C++ for example also had no built-in guarantees for a long time. Making no promises about timing simply means that threading is either a non concept in the language (see C++ before 11) or the language declares everything to do with threading unspecified or undefined.
Re: Tracing JITs and Modern CPUs: Part 2
#9Earlier quoted context omitted.
In theory blogging on github issues could actually be quite convenient. - Great(==standardized) markdown support. - Easy image support. - Uptime is someone else's problem. - Sending someone your blog also directly links them to your ~entire public codebase. - Builtin sane commenting system. - Can keep code beside the blog. Its aggravating to find a living blog that links to a dead code host. - Free with zero setup co…
All of that works with hosting md files in github repo or in gists, but with them you also get a convenient version control system also known as git.
Even the wiki is a git repo, though there's no built in search like there is for repositories and issues.
Re: Tracing JITs and Modern CPUs: Part 2
#10Forgive my ignorance, but when writing a sufficiently large program, why would looking into the generated assembly be of use to a programmer? Wouldn't this turn into an arbitrarily large amount of instructions to sift through just to measure performance?