[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

1 files changed, 113 insertions, 0 deletions

diff --git a/polly/include/polly/Support/ISLTools.h b/polly/include/polly/Support/ISLTools.h
index d6691723264..0dfb5303909 100644
--- a/polly/include/polly/Support/ISLTools.h
+++ b/polly/include/polly/Support/ISLTools.h
@@ -410,6 +410,119 @@ isl::union_map applyDomainRange(isl::union_map UMap, isl::union_map Func);
 ///
 /// @return { Domain[] -> Range[] }
 isl::map intersectRange(isl::map Map, isl::union_set Range);
+
+/// If @p PwAff maps to a constant, return said constant. If @p Max/@p Min, it
+/// can also be a piecewise constant and it would return the minimum/maximum
+/// value. Otherwise, return NaN.
+isl::val getConstant(isl::pw_aff PwAff, bool Max, bool Min);
+
+/// Dump a description of the argument to llvm::errs().
+///
+/// In contrast to isl's dump function, there are a few differences:
+/// - Each polyhedron (pieces) is written on its own line.
+/// - Spaces are sorted by structure. E.g. maps with same domain space are
+///   grouped. Isl sorts them according to the space's hash function.
+/// - Pieces of the same space are sorted using their lower bound.
+/// - A more compact to_str representation is used instead of Isl's dump
+///   functions that try to show the internal representation.
+///
+/// The goal is to get a better understandable representation that is also
+/// useful to compare two sets. As all dump() functions, its intended use is to
+/// be called in a debugger only.
+///
+/// isl_map_dump example:
+/// [p_0, p_1, p_2] -> { Stmt0[i0] -> [o0, o1] : (o0 = i0 and o1 = 0 and i0 > 0
+/// and i0 <= 5 - p_2) or (i0 = 0 and o0 = 0 and o1 = 0); Stmt3[i0] -> [o0, o1]
+/// : (o0 = i0 and o1 = 3 and i0 > 0 and i0 <= 5 - p_2) or (i0 = 0 and o0 = 0
+/// and o1 = 3); Stmt2[i0] -> [o0, o1] : (o0 = i0 and o1 = 1 and i0 >= 3 + p_0 -
+/// p_1 and i0 > 0 and i0 <= 5 - p_2) or (o0 = i0 and o1 = 1 and i0 > 0 and i0
+/// <= 5 - p_2 and i0 < p_0 - p_1) or (i0 = 0 and o0 = 0 and o1 = 1 and p_1 >= 3
+/// + p_0) or (i0 = 0 and o0 = 0 and o1 = 1 and p_1 < p_0) or (p_0 = 0 and i0 =
+/// 2 - p_1 and o0 = 2 - p_1 and o1 = 1 and p_2 <= 3 + p_1 and p_1 <= 1) or (p_1
+/// = 1 + p_0 and i0 = 0 and o0 = 0 and o1 = 1) or (p_0 = 0 and p_1 = 2 and i0 =
+/// 0 and o0 = 0 and o1 = 1) or (p_0 = -1 and p_1 = -1 and i0 = 0 and o0 = 0 and
+/// o1 = 1); Stmt1[i0] -> [o0, o1] : (p_0 = -1 and i0 = 1 - p_1 and o0 = 1 - p_1
+/// and o1 = 2 and p_2 <= 4 + p_1 and p_1 <= 0) or (p_0 = 0 and i0 = -p_1 and o0
+/// = -p_1 and o1 = 2 and p_2 <= 5 + p_1 and p_1 < 0) or (p_0 = -1 and p_1 = 1
+/// and i0 = 0 and o0 = 0 and o1 = 2) or (p_0 = 0 and p_1 = 0 and i0 = 0 and o0
+/// = 0 and o1 = 2) }
+///
+/// dumpPw example (same set):
+/// [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;
+///   Stmt1[0] -> [0, 2] : p_1 = 0 and p_0 = 0;
+///   Stmt1[1 - p_1] -> [1 - p_1, 2] : p_0 = -1 and p_1 <= 0 and p_2 <= 4 + p_1;
+///   Stmt1[-p_1] -> [-p_1, 2] : p_0 = 0 and p_1 < 0 and p_2 <= 5 + p_1;
+///   Stmt2[0] -> [0, 1] : p_1 >= 3 + p_0;
+///   Stmt2[0] -> [0, 1] : p_1 < p_0;
+///   Stmt2[0] -> [0, 1] : p_1 = 1 + p_0;
+///   Stmt2[0] -> [0, 1] : p_1 = 2 and p_0 = 0;
+///   Stmt2[0] -> [0, 1] : p_1 = -1 and p_0 = -1;
+///   Stmt2[i0] -> [i0, 1] : i0 >= 3 + p_0 - p_1 and 0 < i0 <= 5 - p_2;
+///   Stmt2[i0] -> [i0, 1] : 0 < i0 <= 5 - p_2 and i0 < p_0 - p_1;
+///   Stmt2[2 - p_1] -> [2 - p_1, 1] : p_0 = 0 and p_1 <= 1 and p_2 <= 3 + p_1;
+///   Stmt3[0] -> [0, 3];
+///   Stmt3[i0] -> [i0, 3] : 0 < i0 <= 5 - p_2
+/// }
+/// @{
+void dumpPw(const isl::set &Set);
+void dumpPw(const isl::map &Map);
+void dumpPw(const isl::union_set &USet);
+void dumpPw(const isl::union_map &UMap);
+void dumpPw(__isl_keep isl_set *Set);
+void dumpPw(__isl_keep isl_map *Map);
+void dumpPw(__isl_keep isl_union_set *USet);
+void dumpPw(__isl_keep isl_union_map *UMap);
+/// @}
+
+/// Dump all points of the argument to llvm::errs().
+///
+/// Before being printed by dumpPw(), the argument's pieces are expanded to
+/// contain only single points. If a dimension is unbounded, it keeps its
+/// representation.
+///
+/// This is useful for debugging reduced cases where parameters are set to
+/// constants to keep the example simple. Such sets can still contain
+/// existential dimensions which makes the polyhedral hard to compare.
+///
+/// Example:
+///   { [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)) }
+///
+/// dumpExpanded:
+/// {
+///   [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]]
+/// }
+/// @{
+void dumpExpanded(const isl::set &Set);
+void dumpExpanded(const isl::map &Map);
+void dumpExpanded(const isl::union_set &USet);
+void dumpExpanded(const isl::union_map &UMap);
+void dumpExpanded(__isl_keep isl_set *Set);
+void dumpExpanded(__isl_keep isl_map *Map);
+void dumpExpanded(__isl_keep isl_union_set *USet);
+void dumpExpanded(__isl_keep isl_union_map *UMap);
+/// @}
+
 } // namespace polly
 
 #endif /* POLLY_ISLTOOLS_H */