test_mapper.cc: do not assume parameters have a fixed position

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

Author: Sven Verdoolaege

include/tc/core/polyhedral/scop.h

@@ -118,12 +118,12 @@ struct Scop {
     writes = writes.intersect_params(globalParameterContext);
   }
 
-  // Returns a set that specializes (all) the scop's parameter space to the
-  // integer values passed to the function.
-  // WARNING: this version relies on parameter ordering, be sure you know what
-  // you are doing.
+  // Returns a set that specializes the named scop's subset of
+  // parameter space to the integer values passed to the function.
   template <typename T>
-  isl::set makeContext(const std::vector<T>& sizes = std::vector<T>()) const {
+  isl::set makeContext(
+      const std::unordered_map<std::string, T>& sizes =
+          std::unordered_map<std::string, T>()) const {
     auto s = domain().get_space().params();
     return makeSpecializationSet(s, sizes);
   }
@@ -132,8 +132,7 @@ struct Scop {
   // parameter space to the integer values passed to the function.
   template <typename T>
   isl::set makeContext(
-      const std::unordered_map<std::string, T>& sizes =
-          std::unordered_map<std::string, T>()) const {
+      std::initializer_list<std::pair<const std::string, T>> sizes) {
     auto s = domain().get_space().params();
     return makeSpecializationSet(s, sizes);
   }

include/tc/external/detail/islpp.h

@@ -348,6 +348,14 @@ inline isl::set makeSpecializationSet(
   return makeSpecializationSet(space, aux);
 }
 
+template <typename T>
+inline isl::set makeSpecializationSet(
+    isl::space space,
+    std::initializer_list<std::pair<const std::string, T>> paramValues) {
+  std::unordered_map<std::string, T> map(paramValues);
+  return makeSpecializationSet(space, map);
+}
+
 // WARNING: this version relies on parameter ordering, be sure you know what
 // you are doing.
 template <typename T>

test/test_mapper.cc

@@ -333,7 +333,7 @@ TEST_F(PolyhedralMapperTest, MergedContexts) {
   auto scop = PrepareAndJoinBands(makeMatmulTc());
 
   // Unit test claims to use scop->globalParameterContext properly
-  auto context = scop->makeContext(std::vector<int>{64, 64, 64});
+  auto context = scop->makeContext<int>({{"M", 64}, {"N", 64}, {"K", 64}});
   auto& globalParameterContext =
       const_cast<isl::set&>(scop->globalParameterContext);
   globalParameterContext = globalParameterContext.intersect(context);
@@ -349,7 +349,7 @@ TEST_F(PolyhedralMapperTest, FilterMerge) {
   auto schedule = scop->scheduleRoot();
 
   // Unit test claims to use scop->globalParameterContext properly
-  auto context = scop->makeContext(std::vector<int>{64, 64, 64});
+  auto context = scop->makeContext<int>({{"M", 64}, {"N", 64}, {"K", 64}});
   auto& globalParameterContext =
       const_cast<isl::set&>(scop->globalParameterContext);
   globalParameterContext = globalParameterContext.intersect(context);