include missing ISL header file

to be able to compile with ISL master as of today
1df91d8515ec88dc7f7f597168ad0f34f26de5a7

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@183023 91177308-0d34-0410-b5e6-96231b3b80d8
Test that independent block pass does not transform induction variables

The original test case showed a problem with the independet blocks pass and
we decided to XFAIL it for now. Unfortunately the failure is not detected if
we build without asserts and the verification of the independent block pass
is not run. This change tests now for the actual reason of the failure and
should trigger even in a non asserts build. We did not yet solve the underlying
bug, but this should at least make the test suite behavior consistent.

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@183025 91177308-0d34-0410-b5e6-96231b3b80d8
Update isl to include isl_val changes

The latest version of isl includes a new data type isl_val, which properly hides
the multi precision math library used by isl. In Polly we would like to replace
all uses of isl_int with the corresponding isl_val interfaces. This will allow
us to switch the multi precision math library in isl. This is especially
interesting for people who would like to replace libgmp with a non-gpl licensed
library (e.g. imath).

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@183026 91177308-0d34-0410-b5e6-96231b3b80d8