Linked by David Adams on Tue 29th Jun 2010 18:01 UTC, submitted by Michael
Graphics, User Interfaces The open-source Mesa/X.Org developers have been working on LLVMpipe, a Gallium3D driver that accelerates OpenGL and other state trackers on the CPU rather than any GPU driver to provide a better software rasterizer via LLVM optimizations. Unfortunately, it's still slow and can barely keep up with games.
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RE: "Still slow"?
by Neolander on Wed 30th Jun 2010 08:54 UTC in reply to ""Still slow"?"
Neolander
Member since:
2010-03-08

Well, I'd like a comparison with Haiku's drawing engine in terms of 2D performance myself ^^

By the way, can someone tell me how changing the compiler, would the new one be blessed by Apple's touch or not, is supposed to lead to a tremendous improvement in software performance ? I mean, GCC has been here for a long time, so the remaining performance improvement to be done in the compiler area are probably either of the nitpicking kind (1% size improvement in a very specific use case) or leading to compilation being 10 times slower...

Reply Parent Score: 3

RE[2]: "Still slow"?
by boofar on Wed 30th Jun 2010 13:37 in reply to "RE: "Still slow"?"
boofar Member since:
2008-04-23

The driver itself is was probably compiled with GCC; however LLVM is being used internally to JIT-compile rendering instructions (probably in the form of OpenGL Shading Language) into some internal form (or native code, I don't know). Using GCC for that would probably be rather awkward.

Anyway, software rendering is slow compared to dedicated hardware? Mindblowing!!! [/irony]

Reply Parent Score: 1

RE[2]: "Still slow"?
by Zifre on Wed 30th Jun 2010 13:49 in reply to "RE: "Still slow"?"
Zifre Member since:
2009-10-04

LLVM is only used for code generation - the driver is most likely still compiled with GCC.

GCC is generally slightly faster than LLVM, but it takes at least 10 times as many man-hours to use GCC's backend as it does to use LLVM (and I'm really not exaggerating there).

Also, while GCC might produce slightly faster code, LLVM can do its optimizations and code generation several times faster, which is important for startup speed, when you have to generate an entire OpenGL software renderer plus shaders.

Reply Parent Score: 2