[Polly][Isl] Use the function unsignedFromIslSize to manage a isl::size object. NFCI

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in li

[Polly][Isl] Use the function unsignedFromIslSize to manage a isl::size object. NFCI

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in lib/External/isl/include/isl/isl-noxceptions.h and the official isl C++ interface.
In the official interface the type `isl::size` cannot be casted to an unsigned without previously having checked if it contains a valid value with the function `isl::size::is_error()`.
For this reason two helping functions have been added:
- `IslAssert`: assert that no errors are present in debug builds and just disables the mandatory error check in non-debug builds
- `unisgnedFromIslSIze`: cast the `isl::size` object to `unsigned`

Changes made:
- Add the functions `IslAssert` and `unsignedFromIslSize`
- Add the utility function `rangeIslSize()`
- Retype `MaxDisjunctsInDomain` from `int` to `unsigned`
- Retype `RunTimeChecksMaxAccessDisjuncts` from `int` to `unsigned`
- Retype `MaxDimensionsInAccessRange` from `int` to `unsigned`
- Replaced some usages of `isl_size` to `unsigned` since we aim not to use `isl_size` anymore
- `isl-noexceptions.h` has been generated by https://github.com/patacca/isl/commit/e704f73c88f0b4d88e62e447bdb732cf5914094b

No functional change intended.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D113101

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[Polly][Isl] Move to the new-polly-generator branch version of isl-noexceptions.h. NFCI

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in

[Polly][Isl] Move to the new-polly-generator branch version of isl-noexceptions.h. NFCI

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

With this commit we are moving from the `polly-generator` branch to the `new-polly-generator` branch that is more mantainable and is based on the official C++ interface `cpp-checked.h`.

Changes made:
- There are now many sublcasses for `isl::ast_node` representing different isl types. Use `isl::ast_node_for`, `isl::ast_node_user`, `isl::ast_node_block` and `isl::ast_node_mark` where needed.
- There are now many sublcasses for `isl::schedule_node` representing different isl types. Use `isl::schedule_node_mark`, `isl::schedule_node_extension`, `isl::schedule_node_band` and `isl::schedule_node_filter` where needed.
- Replace the `isl::*::dump` with `dumpIslObj` since the isl dump method is not exposed in the C++ interface.
- `isl::schedule_node::get_child` has been renamed to `isl::schedule_node::child`
- `isl::pw_multi_aff::get_pw_aff` has been renamed to `isl::pw_multi_aff::at`
- The constructor `isl::union_map(isl::union_pw_multi_aff)` has been replaced with the static method `isl::union_map::from()`
- Replace usages of `isl::val::add_ui` with `isl::val::add`
- `isl::union_set_list::alloc` is now a constructor
- All the `isl_size` values are now wrapped inside the class `isl::size` use `isl::size::release` to get the internal `isl_size` value where needed.
- `isl-noexceptions.h` has been generated by https://github.com/patacca/isl/commit/73f5ed1f4d1f72582f731590ef9e43d9ab1956ad

No functional change intended.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D107225

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[Polly][Isl] Use isl::union_map::unite() instead of isl::union_map::add_map(). NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib

[Polly][Isl] Use isl::union_map::unite() instead of isl::union_map::add_map(). NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Use `isl::union_map::unite()` instead of `isl::union_map::add_map()`
- `isl-noexceptions.h` has been generated by this https://github.com/patacca/isl/commit/3f43ae29fa2a22936a583b85b2fe8d439f805d8d

Depends on D106059

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D106061

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[Polly][Isl] Stop generating isl::union_{set,map} from isl::space. NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/is

[Polly][Isl] Stop generating isl::union_{set,map} from isl::space. NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Stop generating `isl::union_set` and isl::union_map` from `isl::space` and instead generate them from `isl::ctx`
- Disable clang-format on `isl-noexceptions.h`
- Removed `isl::union_{set,map}` generator from `isl::space` from `isl-noexceptions.h`
- `isl-noexceptions.h` has been generated by this https://github.com/patacca/isl/commit/87c3413b6f1d62ca3dddf716352f90a0b8533353

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D106059

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[Polly][Isl] Use isl::*::ctx instead of isl::*::get_ctx. NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/

[Polly][Isl] Use isl::*::ctx instead of isl::*::get_ctx. NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Use `isl::*::ctx()` instead of `isl::*::get_ctx()` (for example `isl::space::ctx()` instead of `isl::space::get_ctx()`)
- Add `isl::` namespace in front of isl types to avoid confusion (for example `isl::space::ctx` and `isl::ctx`
- `isl-noexceptions.h` has been generated by this https://github.com/patacca/isl/commit/b64e33c62d3fe7db506f6630f9e935b663f9c5a4

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D105691

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[Polly][Isl] Use isl::set::tuple_dim, isl::map::domain_tuple_dim and isl::map::range_tuple_dim. NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now

[Polly][Isl] Use isl::set::tuple_dim, isl::map::domain_tuple_dim and isl::map::range_tuple_dim. NFC

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Use `isl::set::tuple_dim` instead of `isl::set::dim` and `isl::set::n_dim`
- Use `isl::map::domain_tuple_dim` instead of `isl::map::dim`
- Use `isl::map::range_tuple_dim` instead of `isl::map::dim`
- isl-noexceptions.h has been generated by this https://github.com/patacca/isl/commit/45576e1b4260f91946e4cf819485f57bd2ed5490

Note that not all the usage of `isl::{set,map}::dim` where replaced

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D104994

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[Polly][Isl] Removing explicit operator bool() from isl C++ bindings. NFC.

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/Externa

[Polly][Isl] Removing explicit operator bool() from isl C++ bindings. NFC.

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Removing explicit operator bool() from all the classes in the isl C++ bindings.
- Replace each call to operator bool() to method `is_null()`.
- isl-noexceptions.h has been generated by this https://github.com/patacca/isl/commit/27396daac5a5ee8228d25511a12f4a814c92ba8f

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D103976

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[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

This is part of an effort to reduce the differences between the c

[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Removed `std::nullptr_t` constructor from all the classes in the isl C++ bindings.
- `isl-noexceptions.h` has been generated by this https://github.com/patacca/isl/commit/a7e00bea38f251a4bcf5c2c6ce5fa7ee5f661528

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D103751

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Revert "[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC."

This reverts commit be5e2fc7bf781c7fc079943552ea1b519f45c815.

This introduced a building error for polly. https://lab.llvm

Revert "[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC."

This reverts commit be5e2fc7bf781c7fc079943552ea1b519f45c815.

This introduced a building error for polly. https://lab.llvm.org/buildbot#builders/10/builds/4951

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[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

This is part of an effort to reduce the differences between the c

[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
- Removed `std::nullptr_t` constructor from all the classes in the isl C++ bindings.
- `isl-noexceptions.h` has been generated by this https://github.com/patacca/isl/commit/a7e00bea38f251a4bcf5c2c6ce5fa7ee5f661528

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D103751

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[Polly] Regenerate isl-noexceptions.h.

Regenerate the C++ wrapper header from the current isl version's
headers.

The most notable change is that some dimension sizes are represented by
an isl_size

[Polly] Regenerate isl-noexceptions.h.

Regenerate the C++ wrapper header from the current isl version's
headers.

The most notable change is that some dimension sizes are represented by
an isl_size (instead of unsigned), which is a signed int. Additionally,
some function may return -1 in case of an error which already had been
fixed in the past. The C++ may no return -1 instead of UINT_MAX which
caused the problems.

Some types in Polly had been changed from unsigned to isl_size
(that were not already auto) and some loops/comparision had to be
changed to avoid unsigned/signed comparison warnings.

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Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the ne

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636

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Rebase C++ bindings on top of latest isl bindings

The main difference in this change is that isl_stat is now always
checked by default. As we elminiated most used of isl_stat, thanks to
Philip Pfaff

Rebase C++ bindings on top of latest isl bindings

The main difference in this change is that isl_stat is now always
checked by default. As we elminiated most used of isl_stat, thanks to
Philip Pfaffe's implementation of foreach, only a small set of changes
is needed.

This change does not include the following recent changes to isl's C++
bindings:

- stricter error handling for isl_bool
- dropping of the isl::namespace qualifiers

The former requires a larger patch in Polly and consequently should go
through a patch-review. The latter will be applied in the next commit to
keep this commit free from noise.

We also still apply a couple of other changes on top of the official isl
bindings. This delta is expected to shrink over time.

llvm-svn: 338504

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[FlattenAlgo] Replace more isl foreach calls with for loops

This time we replace for loops where the return isl::stat::error has
been used to carry status information.

There are still two uses of f

[FlattenAlgo] Replace more isl foreach calls with for loops

This time we replace for loops where the return isl::stat::error has
been used to carry status information.

There are still two uses of foreach remaining as we do not have a
corresponding for implementation for pw_aff functions.

llvm-svn: 337239

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[FlattenAlgo] Replace some isl foreach calls with for loops

Replace foreach calls which only return 'ok' with for loops.

llvm-svn: 337238

[polly] Update uses of DEBUG macro to LLVM_DEBUG.

The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\

[polly] Update uses of DEBUG macro to LLVM_DEBUG.

The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM

Differential Revision: https://reviews.llvm.org/D44978

llvm-svn: 332352

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[Polly] Add dumpPw() and dumpExpanded() functions. NFC.

These functions print a multi-line and sorted representation of unions
of polyhedra. Each polyhedron (basic_{ast/map}) has its own line.
First

[Polly] Add dumpPw() and dumpExpanded() functions. NFC.

These functions print a multi-line and sorted representation of unions
of polyhedra. Each polyhedron (basic_{ast/map}) has its own line.
First sort key is the polyhedron's hierachical space structure.
Secondary sort key is the lower bound of the polyhedron, which should
ensure that the polyhedral are printed in approximately ascending order.

Example output of dumpPw():
[p_0, p_1, p_2] -> {
Stmt0[0] -> [0, 0];
Stmt0[i0] -> [i0, 0] : 0 < i0 <= 5 - p_2;
Stmt1[0] -> [0, 2] : p_1 = 1 and p_0 = -1;
Stmt2[0] -> [0, 1] : p_1 >= 3 + p_0;
Stmt3[0] -> [0, 3];
}

In contrast dumpExpanded() prints each point in the sets, unless there
is an unbounded dimension that cannot be expandend.
This is useful for reduced test cases where the loop counts are set to
some constant to understand a bug.

Example output of dumpExpanded(
{ [MemRef_A[i0] -> [i1]] : (exists (e0 = floor((1 + i1)/3): i0 = 1 and
3e0 <= i1 and 3e0 >= -1 + i1 and i1 >= 15 and i1 <= 25)) or (exists (e0
= floor((i1)/3): i0 = 0 and 3e0 < i1 and 3e0 >= -2 + i1 and i1 > 0 and
i1 <= 11)) }):

{
[MemRef_A[0] ->[1]];
[MemRef_A[0] ->[2]];
[MemRef_A[0] ->[4]];
[MemRef_A[0] ->[5]];
[MemRef_A[0] ->[7]];
[MemRef_A[0] ->[8]];
[MemRef_A[0] ->[10]];
[MemRef_A[0] ->[11]];
[MemRef_A[1] ->[15]];
[MemRef_A[1] ->[16]];
[MemRef_A[1] ->[18]];
[MemRef_A[1] ->[19]];
[MemRef_A[1] ->[21]];
[MemRef_A[1] ->[22]];
[MemRef_A[1] ->[24]];
[MemRef_A[1] ->[25]]
}

Differential Revision: https://reviews.llvm.org/D38349

llvm-svn: 314525

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[isl++] Rebase isl C++ bindings on top of 29aee98ce

This reduces the diff to the official isl C++ bindings and solves a correctness
issue with isl::booleans, where isl_bool_error results were accide

[isl++] Rebase isl C++ bindings on top of 29aee98ce

This reduces the diff to the official isl C++ bindings and solves a correctness
issue with isl::booleans, where isl_bool_error results were accidentally
converted to isl::boolean::true.

llvm-svn: 303505

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[isl++] Move isl raw_ostream printers into separate header

Instead of relying on these functions to be part of the isl C++ bindings, we
just define this functionality independently. This allows us t

[isl++] Move isl raw_ostream printers into separate header

Instead of relying on these functions to be part of the isl C++ bindings, we
just define this functionality independently. This allows us to use isl C++
bindings that do not contain LLVM specific functionality.

llvm-svn: 303503

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Use isl C++ foreach implementation

This commit switches Polly over to the isl::obj::foreach_* implementation, which
is part of the new isl bindings and follows the foreach pattern established in
Pol

Use isl C++ foreach implementation

This commit switches Polly over to the isl::obj::foreach_* implementation, which
is part of the new isl bindings and follows the foreach pattern established in
Polly by Michael Kruse.

The original isl C function:

isl_stat isl_union_set_foreach_set(__isl_keep isl_union_set *uset,
isl_stat (*fn)(__isl_take isl_set *set, void *user), void *user);

which required the user to define a static callback function to which all
interesting parameters are passed via a 'void *' user-pointer, is on the
C++ side available as a function that takes a std::function<>, which can
carry any additional arguments without the need for a user pointer:

stat UnionSet::foreach_set(const std::function<stat(set)> &fn) const;

The following code illustrates the use of the new C++ interface:

auto Lambda = [=, &Result](isl::set Set) -> isl::stat {
auto Shifted = shiftDimension(Set, Pos, Amount);
Result = Result.add(Shifted);
return isl::stat::ok;
}

UnionSet.foreach_set(Lambda);

Polly had some specialized foreach functions which did not require the lambdas
to return a status flag. We remove these functions in this commit to move Polly
completely over to the new isl interface. We may in the future discuss if
functors without return values can be supported easily.

Another extension proposed by Michael Kruse is the use of C++ iterators to allow
the use of normal for loops to iterate over these sets. Such an extension would
allow us to further simplify the code.

Reviewed-by: Michael Kruse <[email protected]>

Differential Revision: https://reviews.llvm.org/D30620

llvm-svn: 300323

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[FlattenAlgo] Translate to C++ bindings

Translate the full algorithm to use the new isl C++ bindings

This is a large piece of code that has been written with the Polly IslPtr<>
memory management to

[FlattenAlgo] Translate to C++ bindings

Translate the full algorithm to use the new isl C++ bindings

This is a large piece of code that has been written with the Polly IslPtr<>
memory management tool, which only performed memory management, but did not
provide a method interface. As such the code was littered with calls to
give(), copy(), keep(), and take(). The diff of this change should give a
good example how the new method interface simplifies the code by removing the
need for switching between managed types and C functions all the time
and consequently also the need to use the long C function names.

These are a couple of examples comparing the old IslPtr memory management
interface with the complete method interface.

Check properties
----------------

Before:

if (isl_aff_is_zero(Aff.get()) || isl_aff_is_one(Aff.get()))
return true;

After:

if (Aff.is_zero() || Aff.is_one())
return true;

Type conversion
---------------

Before:

isl_union_pw_multi_aff *UPMA =
give(isl_union_pw_multi_aff_from_union_map(UMap.copy());

After:

isl::union_pw_multi_aff UPMA = UMap;

Type construction
-----------------

Before:

auto Empty = give(isl_union_map_empty(Space.copy());

After:

auto Empty = isl::union_map::empty(Space);

Operations
----------

Before:

Set = give(isl_union_set_intersect(Set.copy(), Set2.copy());

After:

Set = Set.intersect(Set2);

Tags: #polly

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D30617

llvm-svn: 297463

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Introduce isl C++ bindings, Part 1: value_ptr style interface

Over the last couple of months several authors of independent isl C++ bindings
worked together to jointly design an official set of isl

Introduce isl C++ bindings, Part 1: value_ptr style interface

Over the last couple of months several authors of independent isl C++ bindings
worked together to jointly design an official set of isl C++ bindings which
combines their experience in developing isl C++ bindings. The new bindings have
been designed around a value pointer style interface and remove the need for
explicit pointer managenent and instead use C++ language features to manage isl
objects.

This commit introduces the smart-pointer part of the isl C++ bindings and
replaces the current IslPtr<T> classes, which served the very same purpose, but
had to be manually maintained. Instead, we now rely on automatically generated
classes for each isl object, which provide value_ptr semantics.

An isl object has the following smart pointer interface:

inline set manage(__isl_take isl_set *ptr);

class set {
friend inline set manage(__isl_take isl_set *ptr);
isl_set *ptr = nullptr;
inline explicit set(__isl_take isl_set *ptr);

public:
inline set();
inline set(const set &obj);
inline set &operator=(set obj);
inline ~set();
inline __isl_give isl_set *copy() const &;
inline __isl_give isl_set *copy() && = delete;
inline __isl_keep isl_set *get() const;
inline __isl_give isl_set *release();
inline bool is_null() const;
}

The interface and behavior of the new value pointer style classes is inspired
by http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3339.pdf, which
proposes a std::value_ptr, a smart pointer that applies value semantics to its
pointee.

We currently only provide a limited set of public constructors and instead
require provide a global overloaded type constructor method "isl::obj
isl::manage(isl_obj *)", which allows to convert an isl_set* to an isl::set by
calling 'S = isl::manage(s)'. This pattern models the make_unique() constructor
for unique pointers.

The next two functions isl::obj::get() and isl::obj::release() are taken
directly from the std::value_ptr proposal:

S.get() extracts the raw pointer of the object managed by S.
S.release() extracts the raw pointer of the object managed by S and sets the
object in S to null.

We additionally add std::obj::copy(). S.copy() returns a raw pointer refering
to a copy of S, which is a shortcut for "isl::obj(oldobj).release()", a
functionality commonly needed when interacting directly with the isl C
interface where all methods marked with __isl_take require consumable raw
pointers.

S.is_null() checks if S manages a pointer or if the managed object is currently
null. We add this function to provide a more explicit way to check if the
pointer is empty compared to a direct conversion to bool.

This commit also introduces a couple of polly-specific extensions that cover
features currently not handled by the official isl C++ bindings draft, but
which have been provided by IslPtr<T> and are consequently added to avoid code
churn. These extensions include:

- operator bool() : Conversion from objects to bool
- construction from nullptr_t
- get_ctx() method
- take/keep/give methods, which match the currently used naming
convention of IslPtr<T> in Polly. They just forward to
(release/get/manage).
- raw_ostream printers

We expect that these extensions are over time either removed or upstreamed to
the official isl bindings.

We also export a couple of classes that have not yet been exported in isl (e.g.,
isl::space)

As part of the code review, the following two questions were asked:

- Why do we not use a standard smart pointer?

std::value_ptr was a proposal that has not been accepted. It is consequently
not available in the standard library. Even if it would be available, we want
to expand this interface with a complete method interface that is conveniently
available from each managed pointer. The most direct way to achieve this is to
generate a specialiced value style pointer class for each isl object type and
add any additional methods to this class. The relevant changes follow in
subsequent commits.

- Why do we not use templates or macros to avoid code duplication?

It is certainly possible to use templates or macros, but as this code is
auto-generated there is no need to make writing this code more efficient. Also,
most of these classes will be specialized with individual member functions in
subsequent commits, such that there will be little code reuse to exploit. Hence,
we decided to do so at the moment.

These bindings are not yet officially part of isl, but the draft is already very
stable. The smart pointer interface itself did not change since serveral months.
Adding this code to Polly is against our normal policy of only importing
official isl code. In this case however, we make an exception to showcase a
non-trivial use case of these bindings which should increase confidence in these
bindings and will help upstreaming them to isl.

Tags: #polly

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D30325

llvm-svn: 297452

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[Support] Remove NonowningIslPtr. NFC.

NonowningIslPtr<isl_X> was used as types of function parameters when the
function does not consume the isl object, i.e. an __isl_keep parameter.

The alternati

[Support] Remove NonowningIslPtr. NFC.

NonowningIslPtr<isl_X> was used as types of function parameters when the
function does not consume the isl object, i.e. an __isl_keep parameter.

The alternatives are:

1. IslPtr<isl_X>
This has additional calls to isl_X_copy and isl_X_free to
increase/decrease the reference counter even though not needed. The
caller already owns a reference to the isl object.

2. const IslPtr<isl_X>&
This does not change the reference counter, but requires an
additional load to get the pointer to the isl object (instead of just
passing the pointer itself).
Moreover, the compiler cannot rely on the constness of the pointer
and has to reload the pointer every time it writes to memory (unless
alias analysis such as TBAA says it is not possible).

The isl C++ bindings currently in development do not have an equivalent
to NonowningIslPtr and adding one would make the binding more
complicated and its advantage in performance is small. In order to
simplify the transition to these C++ bindings, remove NonowningIslPtr.
Change every former use of it to alternative 2 mentioned aboce
(const IslPtr<isl_X>&).

llvm-svn: 295998

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FlattenAlgo: Ensure we _really_ obtain a param space

This resolves "isl_space.c:1775: not a parameter space" errors I have seen
on two systems.

llvm-svn: 281052

Add -polly-flatten-schedule pass.

The -polly-flatten-schedule pass reduces the number of scattering
dimensions in its isl_union_map form to make them easier to understand.
It is not meant to be used

Add -polly-flatten-schedule pass.

The -polly-flatten-schedule pass reduces the number of scattering
dimensions in its isl_union_map form to make them easier to understand.
It is not meant to be used in production, only for debugging and
regression tests.

To illustrate, how it can make sets simpler, here is a lifetime set
used computed by the porposed DeLICM pass without flattening:

{ Stmt_reduction_for[0, 4] -> [0, 2, o2, o3] : o2 < 0;
Stmt_reduction_for[0, 4] -> [0, 1, o2, o3] : o2 >= 5;
Stmt_reduction_for[0, 4] -> [0, 1, 4, o3] : o3 > 0;
Stmt_reduction_for[0, i1] -> [0, 1, i1, 1] : 0 <= i1 <= 3;
Stmt_reduction_for[0, 4] -> [0, 2, 0, o3] : o3 <= 0 }

And here the same lifetime for a semantically identical one-dimensional
schedule:

{ Stmt_reduction_for[0, i1] -> [2 + 3i1] : 0 <= i1 <= 4 }

Differential Revision: https://reviews.llvm.org/D24310

llvm-svn: 280948

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