search for: alloc_size

Hi, I'm implementing the alloc_size function attribute in clang. This attribute exists in gcc since version 4.3. The attribute specifies that a function returns a buffer with the size given by the multiplication of the specified arguments. I would like to add new metadata to pass this information to LLVM IR. For example, take...

On 5/25/12 2:16 AM, Duncan Sands wrote: > Hi John, > >>>> I'm implementing the alloc_size function attribute in clang. >>> does anyone actually use this attribute? And if they do, can it >>> really buy >>> them anything? How about "implementing" it by ignoring it! >> > ... >> >> Currently, SAFECode has a pass which just recogniz...

Hi John, On 25/05/12 17:22, John Criswell wrote: > On 5/25/12 2:16 AM, Duncan Sands wrote: >> Hi John, >> >>>>> I'm implementing the alloc_size function attribute in clang. >>>> does anyone actually use this attribute? And if they do, can it really buy >>>> them anything? How about "implementing" it by ignoring it! >>> >> ... >>> >>> Currently, SAFECode has a pass which jus...

Hi Nuno, > I'm implementing the alloc_size function attribute in clang. does anyone actually use this attribute? And if they do, can it really buy them anything? How about "implementing" it by ignoring it! Ciao, Duncan. This > attribute exists in gcc since version 4.3. > The attribute specifies that a function returns...

Hi John, >>> I'm implementing the alloc_size function attribute in clang. >> does anyone actually use this attribute? And if they do, can it really buy >> them anything? How about "implementing" it by ignoring it! > ... > > Currently, SAFECode has a pass which just recognizes certain functions as > allocators...

On Fri, 25 May 2012 17:43:52 +0200 Duncan Sands <baldrick at free.fr> wrote: > Hi John, > > On 25/05/12 17:22, John Criswell wrote: > > On 5/25/12 2:16 AM, Duncan Sands wrote: > >> Hi John, > >> > >>>>> I'm implementing the alloc_size function attribute in clang. > >>>> does anyone actually use this attribute? And if they do, can it > >>>> really buy them anything? How about "implementing" it by > >>>> ignoring it! > >>> > >> ... > >>> > &...

On Jun 4, 2012, at 10:37 AM, Nuno Lopes <nunoplopes at sapo.pt> wrote: > So here is a new proposal: > > !0 = metadata !{ alloc_siz_fn, offset_fn, parameters* } The parameters are a separate metadata array or the alloc_size metadata is variable length? You'll probably want to write up some docs for the website on how this is supposed to be laid out and work. -eric

On 5/24/12 3:51 AM, Duncan Sands wrote: > Hi Nuno, > >> I'm implementing the alloc_size function attribute in clang. > does anyone actually use this attribute? And if they do, can it really buy > them anything? How about "implementing" it by ignoring it! Tools like ASan and SAFECode *could* use this attribute to determine the size of memory objects created by alloc...

>> On 25/05/12 17:22, John Criswell wrote: >> > On 5/25/12 2:16 AM, Duncan Sands wrote: >> >> Hi John, >> >> >> >>>>> I'm implementing the alloc_size function attribute in clang. >> >>>> does anyone actually use this attribute? And if they do, can it >> >>>> really buy them anything? How about "implementing" it by >> >>>> ignoring it! >> >>> >> >> ... >...

...gt; > --- linux-2.6.orig/net/core/dev.c 2018-04-16 21:08:36.000000000 +0200 > > +++ linux-2.6/net/core/dev.c 2018-04-18 16:24:43.000000000 +0200 > > @@ -8366,7 +8366,8 @@ struct net_device *alloc_netdev_mqs(int > > /* ensure 32-byte alignment of whole construct */ > > alloc_size += NETDEV_ALIGN - 1; > > > > - p = kvzalloc(alloc_size, GFP_KERNEL | __GFP_RETRY_MAYFAIL); > > + WARN_ON(alloc_size > PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER); > > + p = kzalloc(alloc_size, GFP_KERNEL | __GFP_RETRY_MAYFAIL); > > if (!p) > > return NU...

...gt; > --- linux-2.6.orig/net/core/dev.c 2018-04-16 21:08:36.000000000 +0200 > > +++ linux-2.6/net/core/dev.c 2018-04-18 16:24:43.000000000 +0200 > > @@ -8366,7 +8366,8 @@ struct net_device *alloc_netdev_mqs(int > > /* ensure 32-byte alignment of whole construct */ > > alloc_size += NETDEV_ALIGN - 1; > > > > - p = kvzalloc(alloc_size, GFP_KERNEL | __GFP_RETRY_MAYFAIL); > > + WARN_ON(alloc_size > PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER); > > + p = kzalloc(alloc_size, GFP_KERNEL | __GFP_RETRY_MAYFAIL); > > if (!p) > > return NU...

...> be general but only handles C". Consider a language with a string type that > contains the string length as well as the characters. It has a > library function > allocate_string(length). How much does it allocate? length+4 > bytes. That can't > be represented by alloc_size. What's more, it may well store the > length at the > start, and return a pointer to just after the length: a pointer to the first > character. alloc_size can't represent "the allocated memory starts 4 bytes > before the return value" either. In short, it feels li...

Hi, So here is a new proposal: !0 = metadata !{ alloc_siz_fn, offset_fn, parameters* } alloc_size_fn and offset_fn are functions that return either i32/i64 depending on the platform, and they must have the same number of arguments (not necessarily the same as the as allocation function). The parameters are given in the metadata as well. To accommodate the common case, offer_fn can be null...

...istopher <echristo at apple.com>: > On Jun 4, 2012, at 10:37 AM, Nuno Lopes <nunoplopes at sapo.pt> wrote: > >> So here is a new proposal: >> >> !0 = metadata !{ alloc_siz_fn, offset_fn, parameters* } > > The parameters are a separate metadata array or the alloc_size metadata > is variable length? Variable length. I think that's the simplest solution, and the additional overhead of a separate array is probably not worth it. > You'll probably want to write up some docs for the website on how this > is supposed to be laid out and work. Sure...

...ay 2012 17:37:40 +0100 Nuno Lopes <nunoplopes at sapo.pt> wrote: > >> On 25/05/12 17:22, John Criswell wrote: > >> > On 5/25/12 2:16 AM, Duncan Sands wrote: > >> >> Hi John, > >> >> > >> >>>>> I'm implementing the alloc_size function attribute in clang. > >> >>>> does anyone actually use this attribute? And if they do, can > >> >>>> it really buy them anything? How about "implementing" it by > >> >>>> ignoring it! > >> >>> > &...

On Thu, May 24, 2012 at 7:43 PM, John Criswell <criswell at illinois.edu>wrote: > On 5/24/12 3:51 AM, Duncan Sands wrote: > > Hi Nuno, > > > >> I'm implementing the alloc_size function attribute in clang. > > does anyone actually use this attribute? And if they do, can it really > buy > > them anything? How about "implementing" it by ignoring it! > > Tools like ASan and SAFECode *could* use this attribute A case where this may be useful...

...==================== #define THREAD_PER_BLOCK 100 __global__ void VecAdd(double *a,double *b, double *c,int len) { int idx = threadIdx.x + blockIdx.x * blockDim.x; if (idx<len){ c[idx] = a[idx] + b[idx]; } } void vecAdd_kernel(double *ain,double *bin,double *cout,int len){ int alloc_size; alloc_size=len*sizeof(double); /*Step 0a) Make a device copies of ain,bin,and cout.*/ double *a_copy,*b_copy,*cout_copy; /*Step 0b) Allocate memory for device copies.*/ cudaMalloc(&amp;a_copy,alloc_size); cudaMalloc(&amp;b_copy,alloc_size); cudaMalloc(&amp;cou...

>> Hi, >> >> So here is a new proposal: >> >> !0 = metadata !{ alloc_siz_fn, offset_fn, parameters* } >> >> alloc_size_fn and offset_fn are functions that return either i32/i64 >> depending on the platform, and they must have the same number of >> arguments (not necessarily the same as the as allocation function). >> The parameters are given in the metadata as well. >> To accommodate the com...

Hi Nuno, > So here is a new proposal: > > !0 = metadata !{ alloc_siz_fn, offset_fn, parameters* } > > alloc_size_fn and offset_fn are functions that return either i32/i64 > depending on the platform, and they must have the same number of > arguments (not necessarily the same as the as allocation function). > The parameters are given in the metadata as well. > To accommodate the common case, offer_...

>> So here is a new proposal: >> >> !0 = metadata !{ alloc_siz_fn, offset_fn, parameters* } >> >> alloc_size_fn and offset_fn are functions that return either i32/i64 >> depending on the platform, and they must have the same number of >> arguments (not necessarily the same as the as allocation function). >> The parameters are given in the metadata as well. >> To accommodate the com...