Re: Add valgrind support to alloc-pool.c

[Kenneth Zadeck <zadeck at naturalbridge dot com>]

Andrew,

Thanks, this works nicely.  If danny (who originally wrote alloc pool)
does not have any comments, will you check it into the dataflow branch?

Kenny



Andrew Pinski wrote:
> Here is the patch which I promised, I will be sending it out to the list
> once I do a bootstrap/test with it but I tested it on compiling
> insn-attrtab.i at -O2 which should be a good test.
>
> Thanks,
> Andrew Pinski
>
>   
> ------------------------------------------------------------------------
>
> Index: alloc-pool.c
> ===================================================================
> --- alloc-pool.c	(revision 119245)
> +++ alloc-pool.c	(working copy)
> @@ -25,6 +25,19 @@ Software Foundation, 51 Franklin Street,
>  #include "alloc-pool.h"
>  #include "hashtab.h"
>  
> +#ifdef ENABLE_VALGRIND_CHECKING
> +# ifdef HAVE_VALGRIND_MEMCHECK_H
> +#  include <valgrind/memcheck.h>
> +# elif defined HAVE_MEMCHECK_H
> +#  include <memcheck.h>
> +# else
> +#  include <valgrind.h>
> +# endif
> +#else
> +/* Avoid #ifdef:s when we can help it.  */
> +#define VALGRIND_DISCARD(x)
> +#endif
> +
>  #define align_eight(x) (((x+7) >> 3) << 3)
>  
>  /* The internal allocation object.  */
> @@ -224,6 +237,7 @@ pool_alloc (alloc_pool pool)
>  {
>    alloc_pool_list header;
>    char *block;
> +  int size;
>  #ifdef GATHER_STATISTICS
>    struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
>  
> @@ -231,6 +245,7 @@ pool_alloc (alloc_pool pool)
>  #endif
>  
>    gcc_assert (pool);
> +  size = pool->elt_size - offsetof (allocation_object, u.data);
>  
>    /* If there are no more free elements, make some more!.  */
>    if (!pool->free_list)
> @@ -261,6 +276,7 @@ pool_alloc (alloc_pool pool)
>  #endif
>  	header = (alloc_pool_list) USER_PTR_FROM_ALLOCATION_OBJECT_PTR (block);
>  	header->next = pool->free_list;
> +	VALGRIND_DISCARD (VALGRIND_MAKE_NOACCESS (header,size));
>  	pool->free_list = header;
>        }
>        /* Also update the number of elements we have free/allocated, and
> @@ -272,6 +288,7 @@ pool_alloc (alloc_pool pool)
>  
>    /* Pull the first free element from the free list, and return it.  */
>    header = pool->free_list;
> +  VALGRIND_DISCARD (VALGRIND_MAKE_READABLE (header, sizeof(*header)));
>    pool->free_list = header->next;
>    pool->elts_free--;
>  
> @@ -279,6 +296,7 @@ pool_alloc (alloc_pool pool)
>    /* Set the ID for element.  */
>    ALLOCATION_OBJECT_PTR_FROM_USER_PTR (header)->id = pool->id;
>  #endif
> +  VALGRIND_DISCARD (VALGRIND_MAKE_WRITABLE (header, size));
>  
>    return ((void *) header);
>  }
> @@ -288,11 +306,13 @@ void
>  pool_free (alloc_pool pool, void *ptr)
>  {
>    alloc_pool_list header;
> +  int size;
> +  size = pool->elt_size - offsetof (allocation_object, u.data);
>  
>    gcc_assert (ptr);
>  
>  #ifdef ENABLE_CHECKING
> -  memset (ptr, 0xaf, pool->elt_size - offsetof (allocation_object, u.data));
> +  memset (ptr, 0xaf, size);
>  
>    /* Check whether the PTR was allocated from POOL.  */
>    gcc_assert (pool->id == ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id);
> @@ -307,6 +327,7 @@ pool_free (alloc_pool pool, void *ptr)
>    header = (alloc_pool_list) ptr;
>    header->next = pool->free_list;
>    pool->free_list = header;
> +  VALGRIND_DISCARD (VALGRIND_MAKE_NOACCESS (ptr, size));
>    pool->elts_free++;
>  }
>  /* Output per-alloc_pool statistics.  */
>