SRA bit-field optimization

[Richard Sandiford]

"John David Anglin" <dave@hiauly1.hia.nrc.ca> writes:
>> Alexandre Oliva <aoliva@redhat.com> writes:
>> > Anyhow, this patch, that supersedes the previous, fixes it, and with
>> > it the testcase appears to yield the correct result.
>> 
>> Thanks, the results after this patch are much better.  As you say,
>> 20000113-1.c is well and truly fixed.  The only remaining C regressions are:
>
>> FAIL: gcc.c-torture/execute/991118-1.c compilation,  -O3 -fomit-frame-pointer  (internal compiler error)
>> FAIL: gcc.c-torture/execute/991118-1.c compilation,  -O3 -g  (internal compiler error)
>
>> Don't worry about the 991118-1.c failure.  It's an RTL ICE, and probably
>> a config/mips bug.  I'll have a look at it.
>
> I'm also still seeing the failure of 991118-1.c.

Ah, thanks.  I did have a quick look at it, and it seemed to be caused
by a missing conversion at the tree level.  Expand was being given
a BIT_AND_EXPR with a DImode-typed result and HImode-typed operand.
I didn't try to track down where it was coming from.  So it does seem
to be a tree-level bug after all.

Richard