Commit Graph

2 Commits

Author SHA1 Message Date
Eli Friedman a75d53c83f [polly] [ScopInfo] Don't use isl_val_get_num_si.
isl_val_get_num_si crashes on overflow, so don't use it on arbitrary
integers.

Testcase only crashes on platforms where long is 32 bits because of the
signature of isl_val_get_num_si; not sure if it's possible to write a
testcase which crashes if long is 64 bits.

There are a few other places in polly which use isl_val_get_num_si;
they probably need to be fixed as well. I don't think polly uses any
of the other "long" isl APIs in an unsafe manner.

Differential Revision: https://reviews.llvm.org/D42129

llvm-svn: 322766
2018-01-17 21:59:02 +00:00
Tobias Grosser bedef00e2c [ScopInfo] Fold constant coefficients in array dimensions to the right
This allows us to delinearize code such as the one below, where the array
sizes are A[][2 * n] as there are n times two elements in the innermost
dimension. Alternatively, we could try to generate another dimension for the
struct in the innermost dimension, but as the struct has constant size,
recovering this dimension is easy.

   struct com {
     double Real;
     double Img;
   };

   void foo(long n, struct com A[][n]) {
     for (long i = 0; i < 100; i++)
       for (long j = 0; j < 1000; j++)
         A[i][j].Real += A[i][j].Img;
   }

   int main() {
     struct com A[100][1000];
     foo(1000, A);

llvm-svn: 288489
2016-12-02 08:10:56 +00:00