[PATCH v2 2/3] [gdb] Add gdbarch_dwarf2_reg_piece_offset hook

[Tom Tromey]

Andreas> Significance: The significance of bits is well-defined for integers, and
Andreas> per extension, for any register that holds a fixed-size integer.  But
Andreas> how would you define bit significance for a vector register?

Ok, I see what you mean.

Tom de Vries said the earlier issue was:

    https://dwarfstd.org/issues/161206.2.html

I can't speak for DWARF and TBH have as little to do with it as I can,
but I asked about your case and Mark Wielaard suggested maybe re-filing.

Personally I think bringing up the case of vector registers, where
"least significant bit" isn't really well-defined, would improve the
report.

Simon also mentioned that the "DWARF for GPUs" work might be relevant.
>From our brief discussion on irc it sounded to me like they'd hit the
same sort of issue and came to the same sort of conclusion.

So I guess if you wanted to change this code to treat bit-piece as
ABI-defined, and if this helped with some currently-existing code, then
I'd be inclined to approve that.

thanks,
Tom