| Message ID | 20170509205242.2237-4-tbsaunde+gcc@tbsaunde.org |
|---|---|
| State | New |
| Headers | show |
On Tue, May 9, 2017 at 10:52 PM, <tbsaunde+gcc@tbsaunde.org> wrote: > From: Trevor Saunders <tbsaunde+gcc@tbsaunde.org> > > This gets rid of one allocation per bitmap. Often the bitmap_head is > now on the stack, when it isn't its part of some other struct on the > heap instead of being refered to by that struct. On 64 bit platforms > this will increase the size of such structs by 24 bytes, but its an over > all win since we don't need an 8 byte pointer pointing at the > bitmap_head. Given that the auto_bitmap owns the bitmap_head anyway we > know there would never be a place where two auto_bitmaps would refer to > the same bitmap_head object. Ok. Richard. > gcc/ChangeLog: > > 2017-05-07 Trevor Saunders <tbsaunde+gcc@tbsaunde.org> > > * bitmap.h (class auto_bitmap): Change type of m_bits to > bitmap_head, and adjust ctor / dtor and member operators. > --- > gcc/bitmap.h | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/gcc/bitmap.h b/gcc/bitmap.h > index 7508239cff9..49aec001cb0 100644 > --- a/gcc/bitmap.h > +++ b/gcc/bitmap.h > @@ -823,10 +823,10 @@ bmp_iter_and_compl (bitmap_iterator *bi, unsigned *bit_no) > class auto_bitmap > { > public: > - auto_bitmap () { bits = BITMAP_ALLOC (NULL); } > - ~auto_bitmap () { BITMAP_FREE (bits); } > + auto_bitmap () { bitmap_initialize (&m_bits, &bitmap_default_obstack); } > + ~auto_bitmap () { bitmap_clear (&m_bits); } > // Allow calling bitmap functions on our bitmap. > - operator bitmap () { return bits; } > + operator bitmap () { return &m_bits; } > > private: > // Prevent making a copy that references our bitmap. > @@ -837,7 +837,7 @@ class auto_bitmap > auto_bitmap &operator = (auto_bitmap &&); > #endif > > - bitmap bits; > + bitmap_head m_bits; > }; > > #endif /* GCC_BITMAP_H */ > -- > 2.11.0 >
diff --git a/gcc/bitmap.h b/gcc/bitmap.h index 7508239cff9..49aec001cb0 100644 --- a/gcc/bitmap.h +++ b/gcc/bitmap.h @@ -823,10 +823,10 @@ bmp_iter_and_compl (bitmap_iterator *bi, unsigned *bit_no) class auto_bitmap { public: - auto_bitmap () { bits = BITMAP_ALLOC (NULL); } - ~auto_bitmap () { BITMAP_FREE (bits); } + auto_bitmap () { bitmap_initialize (&m_bits, &bitmap_default_obstack); } + ~auto_bitmap () { bitmap_clear (&m_bits); } // Allow calling bitmap functions on our bitmap. - operator bitmap () { return bits; } + operator bitmap () { return &m_bits; } private: // Prevent making a copy that references our bitmap. @@ -837,7 +837,7 @@ class auto_bitmap auto_bitmap &operator = (auto_bitmap &&); #endif - bitmap bits; + bitmap_head m_bits; }; #endif /* GCC_BITMAP_H */
From: Trevor Saunders <tbsaunde+gcc@tbsaunde.org> This gets rid of one allocation per bitmap. Often the bitmap_head is now on the stack, when it isn't its part of some other struct on the heap instead of being refered to by that struct. On 64 bit platforms this will increase the size of such structs by 24 bytes, but its an over all win since we don't need an 8 byte pointer pointing at the bitmap_head. Given that the auto_bitmap owns the bitmap_head anyway we know there would never be a place where two auto_bitmaps would refer to the same bitmap_head object. gcc/ChangeLog: 2017-05-07 Trevor Saunders <tbsaunde+gcc@tbsaunde.org> * bitmap.h (class auto_bitmap): Change type of m_bits to bitmap_head, and adjust ctor / dtor and member operators. --- gcc/bitmap.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)