Re: [PATCH] c++/97197 - support TARGET_MEM_REF in C/C++ error pretty-printing

[Richard Biener <rguenther@suse.de>]

On Fri, 25 Sep 2020, Jakub Jelinek wrote:

> On Fri, Sep 25, 2020 at 01:11:37PM +0200, Richard Biener wrote:
> > This adds rough support to avoid "'target_mem_ref' not supported by"
> > in diagnostics.  There were recent patches by Martin to sanitize
> > dumping of MEM_REF so I'm not trying to interfere with this here.
> 
> Is that correct?
> I mean, TARGET_MEM_REF encodes more than what MEM_REF encodes,
> so printing it like MEM_REF will ignore many things from there.
> I'd say we should print it like:
> *(type *)(BASE + STEP * INDEX + INDEX2 + OFFSET)
> rather than how we print MEM_REFs as
> *(type *)(BASE + OFFSET)
> (with skipping whatever is NULL in there).
> So instead of adding case MEM_REF: in the second and last hunk
> copy and edit it (perhaps kill the probably unnecessary
> part that checks for *&foo and prints it as foo, because who would
> create TARGET_MEM_REF when MEM_REF could have been used in that case).

See my comment above for Martins attempts to improve things.  I don't
really want to try decide what to do with those late diagnostic IL
printing but my commit was blamed for showing target-mem-ref unsupported.

I don't have much time to spend to think what to best print and what not,
but yes, printing only the MEM_REF part is certainly imprecise.

I'll leave the PR to FE folks.

Thanks,
Richard.

> > 
> > Bootstrap & regtest pending.
> > 
> > OK?
> > 
> > 2020-09-25  Richard Biener  <rguenther@suse.de>
> > 
> > 	PR c++/97197
> > cp/
> > 	* error.c (dump_expr): Handle TARGET_MEM_REF as if it
> > 	were MEM_REF.
> > 
> > c-family/
> > 	* c-pretty-print.c (c_pretty_printer::postfix_expression):
> > 	Handle TARGET_MEM_REF as expression.
> > 	(c_pretty_printer::expression): Handle TARGET_MEM_REF as
> > 	unary_expression.
> > 	(c_pretty_printer::unary_expression): Handle TARGET_MEM_REF
> > 	as if it were MEM_REF.
> 
> 	Jakub
> 
> 

-- 
Richard Biener <rguenther@suse.de>
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