[Bug c/12245] [7/8/9 regression] Uses lots of memory when compiling large initialized arrays

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12245

--- Comment #69 from rguenther at suse dot de <rguenther at suse dot de> ---
On February 27, 2019 8:52:12 PM GMT+01:00, fche at redhat dot com
<gcc-bugzilla@gcc.gnu.org> wrote:
>https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12245
>
>--- Comment #68 from Frank Ch. Eigler <fche at redhat dot com> ---
>(In reply to Jakub Jelinek from comment #67)
>> Are the values completely random or are there big chunks with the
>same
>> values?
>
>I'd suspect pretty random, considering that gzip of the 
>generated source code compresses by only 80%.  In the case
>of the systemtap example, it's approximately a byte dump of the
>.debug_line section, which is relatively efficiently encoded,
>ergo incompressible.

We could add a NATIVE_ENCODE_RANGE_EXPR that encodes a contiguous range of
bytes in native target representation. Of course that has to be kept throughout
GIMPLE.