Segment Register Use

I realize I am one of the few who uses the segment registers
(especially CS and DS) on the ia32 chips for example, and a definite
few with complete segregation models that rival specialized physical
processors...

GCC still fails to use these correctly and if your LLVM still depends
on either Generic or some of the RTL models they use in various
processor definitions, I express concern for optimization and
compilation.

Please at least hint that you intend to optimize and compile using all
functionality of the processor; gcc compiles to binaries 2-3x slower
in many projects due to this assinine problem historicly.

In the machines with far more advanced registers, this is debilitating.

Please inform.

-Wilfred
WilfredGuerin@gmail.com

if your LLVM still depends on either Generic or some of the
RTL models they use in various processor definitions, I
express concern for optimization and compilation.

Thank you for your concerns.

However, LLVM is in the first place an environment to write
compilers. As an example for llvm, it can use the GCC frontend
for compilation. "clang" is another compile, that can compile
programs without any call to any gcc part.

To learn more about code-generation for x86 targets inside LLVM
(e.g. without the help of GCC), look at those files:

http://llvm.org/svn/llvm-project/llvm/trunk/lib/Target/X86

Also, can you provide an example of the same program, once
compiled with the use of CS/DS and once without this? I mean:
show use the assembly code. How far apart is the performance of
those two test programs? For which ABI can you compile with
using CS/DS? AFAIK a Linux environment disables this.

Somehow your mail remembers me at times than I compiled under
MSDOS and I had several memory models to select from,
e.g. "tiny", "medium", "large", "flat" ...

fucking hell, listserv...

fucking hell, listserv...

Wilfred,

Your emails are not in the spirit of the list. This list is for friendly discussion of LLVM related topics. If you don't intend to contribute in a positive way, please take your attitude and language elsewhere.

I've set your account to require moderation before your posts go through. If you would like to contribute constructively to the list, and demonstrate it with your future posts, I'd be happy to reinstate your full access. If not, I will eventually block you from posting to the list entirely.

Thanks for your understanding,

-Chris