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Re: C++ PATCH: use identifier_p instead of naked TREE_CODE == IDENTIFIER_NODE

Jakub Jelinek <> writes:

| On Fri, Mar 22, 2013 at 10:21:05AM +0100, Richard Biener wrote:
| > On Fri, Mar 22, 2013 at 4:50 AM, Gabriel Dos Reis <> wrote:
| > >
| > > This patch introduces identified_p (t) in lieu of
| > >
| > 
| > Generally we have macros like IDENTIFIER_P for this kind of checks.

I know we have macros for this kind of test, and what what I can tell
looking at the source code, nobody actually bothered using it.  

The point of the change isn't to do that test exactly.  As I explained
earlier, the change was prompted by looking at patterns of usage inf the
existing source code: it is very frequent that we would test XXX_P (t)
and immediately do XXX_GET_YYY (t) when XXX_GET_YYY will do a XXX_CHECK (t),
which morally tests again XXX_P (t), and this is all over the places.
The reason why XXX_GET_YYY (t) does XXX_CHECK (t) is because it could be
mistakenly used on a different node since t isn't "typed".  

| > 
| > > in the C++ front-end.  identifier_p is effectively LANG_IDENTIFIER_CAST
| > > except that it returns a typed pointer instead of a boolean value.
| > 
| > Hm?  So you are replacing TREE_CODE (t) == IDENTIFIER_NODE
| > with kind-of dynamic_cast<identifier> (t) (in C++ terms)?  Then
| > naming it identifier_p is bad.  We have is-a.h now, so please try to use
| > a single style of C++-style casting throughout GCC.
| Anyway, if you see better code generated with your change compared to the
| old style, I'd say you should file a PR with some preferrably short
| preprocessed routine where it makes a difference, because that would show
| that either VRP or other optimization pass just isn't doing good job.

We are talking about files in cp/ right?  They don't know what "short"
With the next change, I'll try to find a short file, although currently
I am working on cp/name-lookup.c

| It is better code for --enable-checking=yes anyway, right?


-- Gaby

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