Hi, Jakub Thank you for your detailed explanation. I will try to compare the results of rtl expand as Richard have suggested, to see if I can find anything. May be I can make another patch.
Thanks again. Regards! Hujp > On Thu, Aug 27, 2020 at 11:13:50AM +0000, Hu, Jiangping wrote: > > I'm not sure about if the case should fail. > > So, I add Jakub who committed this testcase. > > > > I thought the case should success, but for changes of gcc of > > years, now it failed. So I think that may be some optimization > > are unnecessary for this testcase, and I found the FRE. > > The intent of the guality testsuite is to track regressions in debug info > quality. Because the testing matrix is huge > (different targets x different -O* options x different gdb versions), > it isn't really feasible to keep xfails for them accurately, so all we > care > about is whether we don't regress compared to older gcc releases for the > same target, same -O* options and same gdb version. > If we do regress e.g. because of some added optimization, the intent is > that it is analyzed why it regressed and if possible some improvements > in the debug info generation are added to deal with the optimization if > possible. > So adding -fno-tree-* is not the right solution, the majority of people > will > not use such options in their codes and so they will observe the debug > info > quality degradation there. > > Jakub > >