Scop::fixParameters: store parameter values in the specialized scop

This will allow the values to be reused in emitCudaKernel.
The values are stored as int because that is the type
used in emitCudaKernel.  Any larger type would only get
truncated there.

Author: Sven Verdoolaege

tc/core/cuda/cuda_tc_executor.cc

@@ -90,7 +90,7 @@ CudaCompilationResult CudaBackend::compileWithTcMapper(
   LOG_IF(INFO, FLAGS_debug_tc_mapper) << "Mapped schedule:" << std::endl
                                       << *(mappedScop->schedule());
 
-  auto parameters = mappedScop->scop().getParameterValues(pvm);
+  auto parameters = mappedScop->scop().getParameterValues();
   auto specializedName = specializeKernelName(tcName, parameters);
 
   // This updates the launch bounds with the actual result from compilation

tc/core/polyhedral/scop.cc

@@ -262,17 +262,17 @@ void Scop::promoteEverythingAt(std::vector<size_t> pos) {
   insertSyncsAroundCopies(tree);
 }
 
-std::vector<long> Scop::getParameterValues(
-    const std::unordered_map<std::string, int>& sizes) const {
+std::vector<long> Scop::getParameterValues() const {
   // Scop holds a vector of Variables.
   // Iterate over parameters in order, checking if the
-  // context contains a parameter whose name corresponds to that
+  // map of known parameter values contains a parameter
+  // whose name corresponds to that
   // Variable and push respective parameter values.
   std::vector<long> paramValues;
   for (auto const& param : halide.params) {
     auto name = param.name();
-    CHECK(sizes.count(name) == 1);
-    paramValues.push_back(sizes.at(name));
+    CHECK(parameterValues.count(name) == 1);
+    paramValues.push_back(parameterValues.at(name));
   }
   return paramValues;
 }

tc/core/polyhedral/scop.h

@@ -63,6 +63,7 @@ struct Scop {
   // Clone a Scop
   static std::unique_ptr<Scop> makeScop(const Scop& scop) {
     auto res = std::unique_ptr<Scop>(new Scop());
+    res->parameterValues = scop.parameterValues;
     res->globalParameterContext = scop.globalParameterContext;
     res->halide = scop.halide;
     res->reads = scop.reads;
@@ -137,18 +138,21 @@ struct Scop {
   }
 
   // Fix the values of the specified parameters in the context
-  // to the corresponding specified values.
+  // to the corresponding specified values and keep track of them
+  // in parameterValues.
   template <typename T>
   void fixParameters(const std::unordered_map<std::string, T>& sizes) {
+    CHECK(parameterValues.size() == 0);
+    for (const auto& kvp : sizes) {
+      parameterValues.emplace(kvp.first, kvp.second);
+    }
     intersectContext(makeContext(sizes));
   }
 
-  // Given a map between TC parametric tensor sizes, represented as strings,
-  // and their numerical values, return the list of parameter values in the same
+  // Return the list of parameter values in the same
   // order as codegen places them in the function signature, i.e. following the
   // order of scop.params.
-  std::vector<long> getParameterValues(
-      const std::unordered_map<std::string, int>& sizes) const;
+  std::vector<long> getParameterValues() const;
 
   isl::id nextGroupIdForTensor(isl::id tensorId) {
     auto ctx = domain().get_ctx();
@@ -490,6 +494,8 @@ struct Scop {
   // of the ScheduleTree "function".
   isl::union_set& domain();
   const isl::union_set domain() const;
+  // The parameter values of a specialized Scop.
+  std::unordered_map<std::string, int> parameterValues;
   // A globalParameterContext is kept. This represents (partial)
   // parameter specialization coming from the outside.
   // This may be further specialized before codegen.