[Bug target/28872] ARM inline assembly can be mispredicated.

[ramana at gcc dot gnu dot org]

------- Comment #3 from ramana at gcc dot gnu dot org  2009-12-22 20:26 -------
(In reply to comment #1)
> The only reason for keeping the old predication-based code is that it can
> handle an important case that the generic code cannot.  Specifically, it can
> conditionally skip a call to a function: this is not normally predicable since
> it clobbers the instruction codes.   However, the arm-specific code knows that
> it is safe to do this iff the call instruction is the last instruction in the
> predicated sequence.
> 


http://gcc.gnu.org/ml/gcc/2009-08/msg00154.html for a thread on the issues with
turning this off for ARM and conditional calls.



> If the MI code could be made to handle cases where the predicate register was
> clobbered by the last predicable instruction, then the need to keep the
> existing MD code could disappear in a puff of smoke.
> 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28872