ICE on m68k-linux in 3_4-branch
Jim Wilson
wilson@specifixinc.com
Mon Jun 7 03:55:00 GMT 2004
Bernardo Innocenti wrote:
> This RTL expression should match the pattern and select the
> !TARGET_COLDFIRE insn:
Yes. Perhaps the stage2 compiler was miscompiled, causing the pattern
match to fail. Try stepping through the code in recog().
> I'm still wondering why the documentation for strict_low_part
> in gccint.texi doesn't look like this RTX.
The pattern is buggy, technically, since it does not create the SUBREG.
However, the passes that actually check for and use the SUBREG are
very limited. I would guess that it is only combine, and I would also
guess that when combine fails to see the required subreg, all it does is
reject a potential combination. Thus the lack of the subreg is
harmless. Maybe you will lose a bit of optimization, but this is likely
rare.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com
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