MapperMemoryPromotionSum2D: do not assume parameters have a fixed position

It doesn't really matter for the use cases in MapperMemoryPromotionSum2D
because all parameters get assigned the same value, but it allows
this variant of makeSpecializationSet to be removed.
Replace it by one that takes an initializer_list.

Author: Sven Verdoolaege

include/tc/external/detail/islpp.h

@@ -356,18 +356,15 @@ inline isl::set makeSpecializationSet(
   return makeSpecializationSet(space, map);
 }
 
-// WARNING: this version relies on parameter ordering, be sure you know what
-// you are doing.
 template <typename T>
 inline isl::set makeSpecializationSet(
     isl::space space,
-    const std::vector<T>& paramValues) {
-  CHECK_EQ(space.dim(isl::dim_type::param), paramValues.size());
-  std::unordered_map<int, T> paramValuesMap;
-  for (int i = 0; i < paramValues.size(); ++i) {
-    paramValuesMap[i] = paramValues[i];
+    std::initializer_list<std::pair<isl::id, T>> paramValues) {
+  std::unordered_map<std::string, T> map;
+  for (auto kvp : paramValues) {
+    map.emplace(kvp.first.get_name(), kvp.second);
   }
-  return makeSpecializationSet(space, paramValuesMap);
+  return makeSpecializationSet(space, map);
 }
 
 namespace detail {

test/test_mapper_memory_promotion.cc

@@ -275,7 +275,7 @@ def fun(float(N, M) A, float(N, M) B) -> (C) {
     blockSpace = blockSpace.set_dim_id(isl::dim_type::param, 0, BX)
                      .set_dim_id(isl::dim_type::param, 1, BY);
     isl::set blockZero =
-        makeSpecializationSet(blockSpace, std::vector<int>{{0, 0}});
+        isl::makeSpecializationSet<int>(blockSpace, {{BX, 0}, {BY, 0}});
 
     // Must have groups for these tensors, in arbitrary order.
     unordered_set<string> names{"A", "B", "C"};