"gold standard"? [LWN.net]

"gold standard"?

Posted Apr 26, 2012 22:57 UTC (Thu) by stevenb (guest, #11536)
In reply to: "gold standard"? by daglwn
Parent article: LFCS 2012: LLVM and Linux

"gcc's generated code is notoriously slow."

There are plenty benchmarks and user stories that say otherwise. IMHO there is a perception problem that is being perpetuated because complaints about GCC (or any other compiler) are always shouted out louder than compliments. And saying anything positive about GCC seems to be salon unfaehig anyway in many Linux discussion forums (especially LKML)...

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"gold standard"?

Posted Apr 27, 2012 1:07 UTC (Fri) by daglwn (guest, #65432) [Link] (1 responses)

As I said, one can show gcc generating faster executables than other compilers on some codes. This will always be so. But the gcc team does not focus on performance exclusively, nor should it.

For all-out performance over a wide range of codes, it's hard to beat compilers that focus on it, such as icc, pathscale and pgi.

"gold standard"?

Posted Apr 29, 2012 8:24 UTC (Sun) by ebiederm (subscriber, #35028) [Link]

A lot depends on what you mean by performance.

Compiling your kernel of numerical code fast is one thing, and there are certainly compilers that specialize in that and all kinds of cpu architecture extensions to take advantage of it.

Where I have seen gcc excel is in making the work-a-day integer code lean and tight and cache friendly.

Most codes are integer codes and we need good work-a-day compilers not the hotrod numerical code wonders that are fast when the compiler does not ICE or generate incorrect code.

With luck clang can catch up to gcc and be a good work-a-day compiler but it seems clear that clang is not there yet.