RE: [PATCH] Fix MIPS LHX in mips-dsp.md

["Fu, Chao-Ying" <fu at mips dot com>]

Maciej W. Rozycki wrote:
> 
> On Thu, 12 Nov 2009, David Daney wrote:
> 
> > > There's a general GCC rule that code patches must be 
> regression-tested
> > > against the full GCC testsuite (or at least all the parts 
> associated
> > > with the languages that your target supports by default). 
>  The idea
> > > is to make sure that no existing tests start to fail 
> after the patch.
> > > If you're confident they won't (and I agree they're unlikely to in
> > > this case), well, all the better!  It should just be a formality.
> > 
> > Several times I have created seemingly trivial patches 
> where I was certain
> > that there would be no regressions.  However, the step of 
> running the
> > testsuite for regressions uncovered some problems.  So I 
> wouldn't classify it
> > a a busy-work type formality, it is an important tool to 
> help us improve
> > quality.
> 
>  And actually even if a change is absolutely correct, the way 
> it modifies 
> behaviour of a piece of software may uncover a bug elsewhere 
> that needs to 
> be fixed (not necessarily by the submitter of the original fix, of 
> course).
> 
>   Maciej
> 

  All your points are great.

  My pain is that this bug isn't caught until now.
Should we add more MIPS target configurations to test? ex: -mdsp/-mdspr2
Passing all GCC regression tests for limited targets is still not enough.
And we should have big tests/applications to exercise the compiler.

  Thanks!

Regards,
Chao-ying