[Bug middle-end/69454] [6 Regression] ix86_expand_prologue internal compiler error: Segmentation fault

[ienkovich at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69454

--- Comment #37 from Ilya Enkovich <ienkovich at gcc dot gnu.org> ---
(In reply to H.J. Lu from comment #36)
> (In reply to Richard Biener from comment #35)
> > I wonder why LRA cannot spill using unaligned moves?
> 
> We keep track precise alignment requirement.  RA will use
> spill/fill the used part of vector registers.  For GPR,
> RA spill/fill the whole register since the minimal stack
> alignment is the GPR size.  In ix86_minimum_alignment,
> since we only spill/fill SI registers, which need 32-bit
> alignment, we return 32 for DImode in 32-bit mode.  Now
> STV introduce DImode spill/fill in 32-bit mode.  If STV
> is used, ix86_minimum_alignment must return 64 for DImode.
> Otherwise, we are lying to RA.

DImode spill/fill in 32-bit mode doesn't have to be 8-byte
aligned.  I think that was the question.