[PATCH][gdb/symtab] Don't create duplicate psymtab for forward-imported CU

[Tom de Vries]

On 22-04-2020 15:45, Simon Marchi wrote:
> On 2020-04-22 2:13 a.m., Tom de Vries wrote:
>>> [ Forgot to mention ]
>>>
>>> Using a 2.8GB libxul.so debug file from opensuse tumbleweed, build with
>>> lto, we have:
>>> ...
>>> $ time.sh gdb -batch -iex "maint set dwarf max-cache-age 1000" -iex "set
>>> language c" usr/lib/debug/usr/lib64/firefox/libxul.so-74.0-1.1.x86_64.debug
>>> maxmem: 10417196
>>> real: 116.62
>>> user: 114.85
>>> system: 2.37
>>> ...
>>> and with this patch:
>>> ...
>>> $ time.sh gdb -batch -iex "maint set dwarf max-cache-age 1000" -iex "set
>>> language c" usr/lib/debug/usr/lib64/firefox/libxul.so-74.0-1.1.x86_64.debug
>>> maxmem: 10436372
>>> real: 77.42
>>> user: 75.54
>>> system: 2.46
>>>
>>> OK for trunk?
> 
> I just glanced at this and... wow, that's a big difference.
> 

Yeah :)

Not as big though as the difference of changing dwarf max-cache-age from
default 5 to 1000 (
https://sourceware.org/bugzilla/show_bug.cgi?id=25703#c1 )

Thanks,
- Tom