On Wed, Apr 20, 2016 at 11:13:42AM +0200, Richard Biener wrote:
> On Wed, Apr 20, 2016 at 8:22 AM,  <tbsaunde+...@tbsaunde.org> wrote:
> > From: Trevor Saunders <tbsaunde+...@tbsaunde.org>
> >
> > Later patches use these functions, and I believe Mikhail has mentioned 
> > before
> > he'd like to have begin / end () on vec before.
> 
> begin() / end () is fine.  But contains ()?  That makes using a O(n) algorithm
> too easy I think (we have qsort + bsearch for a more efficient way).
 Well, contains is better if you will search less than log(n) times.

> I suppose you are replacing linear list walks with contains () so it
> might be ok...

yeah, and I'm not really sure how much open coding it will actually make
people think more than they would otherwise.

> At least stick some comment on contains () mentioning qsort / bsearch.

sure

Trev

> 
> Ok with that change.
> 
> Richard.
> 
> > gcc/ChangeLog:
> >
> > 2016-04-19  Trevor Saunders  <tbsaunde+...@tbsaunde.org>
> >
> >         * vec.h (vec_safe_contains): New function.
> >         (vec::contains): Likewise.
> >         (vec::begin): Likewise.
> >         (vec::end): Likewise.
> > ---
> >  gcc/vec.h | 39 ++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 38 insertions(+), 1 deletion(-)
> >
> > diff --git a/gcc/vec.h b/gcc/vec.h
> > index ff57528..3c16e83 100644
> > --- a/gcc/vec.h
> > +++ b/gcc/vec.h
> > @@ -454,6 +454,10 @@ public:
> >    bool is_empty (void) const { return m_vecpfx.m_num == 0; }
> >    T *address (void) { return m_vecdata; }
> >    const T *address (void) const { return m_vecdata; }
> > +  T *begin () { return address (); }
> > +  const T *begin () const { return address (); }
> > +  T *end () { return address () + length (); }
> > +  const T *end () const { return address () + length (); }
> >    const T &operator[] (unsigned) const;
> >    T &operator[] (unsigned);
> >    T &last (void);
> > @@ -473,6 +477,7 @@ public:
> >    void qsort (int (*) (const void *, const void *));
> >    T *bsearch (const void *key, int (*compar)(const void *, const void *));
> >    unsigned lower_bound (T, bool (*)(const T &, const T &)) const;
> > +  bool contains (const T &search) const;
> >    static size_t embedded_size (unsigned);
> >    void embedded_init (unsigned, unsigned = 0, unsigned = 0);
> >    void quick_grow (unsigned len);
> > @@ -542,7 +547,6 @@ vec_safe_is_empty (vec<T, A, vl_embed> *v)
> >    return v ? v->is_empty () : true;
> >  }
> >
> > -
> >  /* If V does not have space for NELEMS elements, call
> >     V->reserve(NELEMS, EXACT).  */
> >  template<typename T, typename A>
> > @@ -695,6 +699,12 @@ vec_safe_splice (vec<T, A, vl_embed> *&dst, const 
> > vec<T, A, vl_embed> *src
> >      }
> >  }
> >
> > +template<typename T, typename A>
> > +inline bool
> > +vec_safe_contains (vec<T, A, vl_embed> *v, const T &search)
> > +{
> > +  return v? v->contains (search) : false;
> > +}
> >
> >  /* Index into vector.  Return the IX'th element.  IX must be in the
> >     domain of the vector.  */
> > @@ -973,6 +983,19 @@ vec<T, A, vl_embed>::bsearch (const void *key,
> >    return NULL;
> >  }
> >
> > +/* Return true if the vector contains search.  */
> > +
> > +template<typename T, typename A>
> > +inline bool
> > +vec<T, A, vl_embed>::contains (const T &search) const
> > +{
> > +  unsigned int len = length ();
> > +  for (unsigned int i = 0; i < len; i++)
> > +    if ((*this)[i] == search)
> > +      return true;
> > +
> > +  return false;
> > +}
> >
> >  /* Find and return the first position in which OBJ could be inserted
> >     without changing the ordering of this vector.  LESSTHAN is a
> > @@ -1167,6 +1190,10 @@ public:
> >    const T *address (void) const
> >    { return m_vec ? m_vec->m_vecdata : NULL; }
> >
> > +  T *begin () { return address (); }
> > +  const T *begin () const { return address (); }
> > +  T *end () { return begin () + length (); }
> > +  const T *end () const { return begin () + length (); }
> >    const T &operator[] (unsigned ix) const
> >    { return (*m_vec)[ix]; }
> >
> > @@ -1208,6 +1235,7 @@ public:
> >    void qsort (int (*) (const void *, const void *));
> >    T *bsearch (const void *key, int (*compar)(const void *, const void *));
> >    unsigned lower_bound (T, bool (*)(const T &, const T &)) const;
> > +  bool contains (const T &search) const;
> >
> >    bool using_auto_storage () const;
> >
> > @@ -1695,6 +1723,15 @@ vec<T, va_heap, vl_ptr>::lower_bound (T obj,
> >    return m_vec ? m_vec->lower_bound (obj, lessthan) : 0;
> >  }
> >
> > +/* Return true if the vector contains search.  */
> > +
> > +template<typename T>
> > +inline bool
> > +vec<T, va_heap, vl_ptr>::contains (const T &search) const
> > +{
> > +  return m_vec ? m_vec->contains (search) : false;
> > +}
> > +
> >  template<typename T>
> >  inline bool
> >  vec<T, va_heap, vl_ptr>::using_auto_storage () const
> > --
> > 2.7.4
> >

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