[LLVMdev] Inline assembly - multiple constraints and reloads.

[Brett Hale]

This is a question regarding constraint selection (and unnecessary spills)
for gcc inline assembly, originally asked on
stackoverflow<http://stackoverflow.com/questions/16850309/clang-llvm-inline-assembly-multiple-constraints-with-useless-spills-reload>,
regarding code generation by clang / llvm. After receiving a response on
the cfe-dev<http://lists.cs.uiuc.edu/pipermail/cfe-dev/2013-June/030017.html>
list
from Eli Friedman, I wanted to know if there are any significant barriers
to improving inline assembly? Would it require a major refactoring, etc.?

The current situation would seem to present a significant disadvantage for
high performance primitives (e.g., sync / atomic, arithmetic instructions)
required by kernels, C/C++ standard libraries, numerical computing, etc.,
expressed with gcc inline assembly. Does the LLVM project plan to adopt an
inline assembly model better suited to the IR back-end? I guess I'm just
trying to gauge the priorities and direction of development.

Thanks.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130607/293efc33/attachment.html>