Revert "[SYCL] Refactor program build and cache (#8104)"

This reverts commit 2032ce4.

Author: bader

sycl/source/detail/kernel_program_cache.cpp

@@ -14,7 +14,7 @@ namespace sycl {
 __SYCL_INLINE_VER_NAMESPACE(_V1) {
 namespace detail {
 KernelProgramCache::~KernelProgramCache() {
-  for (auto &ProgIt : MCachedPrograms.Cache) {
+  for (auto &ProgIt : MCachedPrograms) {
     ProgramWithBuildStateT &ProgWithState = ProgIt.second;
     PiProgramT *ToBeDeleted = ProgWithState.Ptr.load();
 

sycl/source/detail/kernel_program_cache.hpp

@@ -39,16 +39,13 @@ class KernelProgramCache {
     bool isFilledIn() const { return !Msg.empty(); }
   };
 
-  /// Denotes the state of a build.
-  enum BuildState { BS_InProgress, BS_Done, BS_Failed };
-
   /// Denotes pointer to some entity with its general state and build error.
   /// The pointer is not null if and only if the entity is usable.
   /// State of the entity is provided by the user of cache instance.
   /// Currently there is only a single user - ProgramManager class.
   template <typename T> struct BuildResult {
     std::atomic<T *> Ptr;
-    std::atomic<BuildState> State;
+    std::atomic<int> State;
     BuildError Error;
 
     /// Condition variable to signal that build result is ready.
@@ -65,23 +62,15 @@ class KernelProgramCache {
     /// A mutex to be employed along with MBuildCV.
     std::mutex MBuildResultMutex;
 
-    BuildResult(T *P, BuildState S) : Ptr{P}, State{S}, Error{"", 0} {}
+    BuildResult(T *P, int S) : Ptr{P}, State{S}, Error{"", 0} {}
   };
 
   using PiProgramT = std::remove_pointer<RT::PiProgram>::type;
   using PiProgramPtrT = std::atomic<PiProgramT *>;
   using ProgramWithBuildStateT = BuildResult<PiProgramT>;
   using ProgramCacheKeyT = std::pair<std::pair<SerializedObj, std::uintptr_t>,
                                      std::pair<RT::PiDevice, std::string>>;
-  using CommonProgramKeyT = std::pair<std::uintptr_t, RT::PiDevice>;
-
-  struct ProgramCache {
-    std::map<ProgramCacheKeyT, ProgramWithBuildStateT> Cache;
-    std::multimap<CommonProgramKeyT, ProgramCacheKeyT> KeyMap;
-
-    size_t size() const noexcept { return Cache.size(); }
-  };
-
+  using ProgramCacheT = std::map<ProgramCacheKeyT, ProgramWithBuildStateT>;
   using ContextPtr = context_impl *;
 
   using PiKernelT = std::remove_pointer<RT::PiKernel>::type;
@@ -102,66 +91,21 @@ class KernelProgramCache {
 
   void setContextPtr(const ContextPtr &AContext) { MParentContext = AContext; }
 
-  Locked<ProgramCache> acquireCachedPrograms() {
+  Locked<ProgramCacheT> acquireCachedPrograms() {
     return {MCachedPrograms, MProgramCacheMutex};
   }
 
   Locked<KernelCacheT> acquireKernelsPerProgramCache() {
     return {MKernelsPerProgramCache, MKernelsPerProgramCacheMutex};
   }
 
-  std::pair<ProgramWithBuildStateT *, bool>
-  getOrInsertProgram(const ProgramCacheKeyT &CacheKey) {
-    auto LockedCache = acquireCachedPrograms();
-    auto &ProgCache = LockedCache.get();
-    auto Inserted = ProgCache.Cache.emplace(
-        std::piecewise_construct, std::forward_as_tuple(CacheKey),
-        std::forward_as_tuple(nullptr, BS_InProgress));
-    if (Inserted.second) {
-      // Save reference between the common key and the full key.
-      CommonProgramKeyT CommonKey =
-          std::make_pair(CacheKey.first.second, CacheKey.second.first);
-      ProgCache.KeyMap.emplace(std::piecewise_construct,
-                               std::forward_as_tuple(CommonKey),
-                               std::forward_as_tuple(CacheKey));
-    }
-    return std::make_pair(&Inserted.first->second, Inserted.second);
-  }
-
-  std::pair<KernelWithBuildStateT *, bool>
-  getOrInsertKernel(RT::PiProgram Program, const std::string &KernelName) {
-    auto LockedCache = acquireKernelsPerProgramCache();
-    auto &Cache = LockedCache.get()[Program];
-    auto Inserted = Cache.emplace(
-        std::piecewise_construct, std::forward_as_tuple(KernelName),
-        std::forward_as_tuple(nullptr, BS_InProgress));
-    return std::make_pair(&Inserted.first->second, Inserted.second);
-  }
-
   template <typename T, class Predicate>
   void waitUntilBuilt(BuildResult<T> &BR, Predicate Pred) const {
     std::unique_lock<std::mutex> Lock(BR.MBuildResultMutex);
 
     BR.MBuildCV.wait(Lock, Pred);
   }
 
-  template <typename ExceptionT, typename RetT>
-  RetT *waitUntilBuilt(BuildResult<RetT> *BuildResult) {
-    // Any thread which will find nullptr in cache will wait until the pointer
-    // is not null anymore.
-    waitUntilBuilt(*BuildResult, [BuildResult]() {
-      int State = BuildResult->State.load();
-      return State == BuildState::BS_Done || State == BuildState::BS_Failed;
-    });
-
-    if (BuildResult->Error.isFilledIn()) {
-      const BuildError &Error = BuildResult->Error;
-      throw ExceptionT(Error.Msg, Error.Code);
-    }
-
-    return BuildResult->Ptr.load();
-  }
-
   template <typename T> void notifyAllBuild(BuildResult<T> &BR) const {
     BR.MBuildCV.notify_all();
   }
@@ -188,7 +132,7 @@ class KernelProgramCache {
   ///
   /// This member function should only be used in unit tests.
   void reset() {
-    MCachedPrograms = ProgramCache{};
+    MCachedPrograms = ProgramCacheT{};
     MKernelsPerProgramCache = KernelCacheT{};
     MKernelFastCache = KernelFastCacheT{};
   }
@@ -197,7 +141,7 @@ class KernelProgramCache {
   std::mutex MProgramCacheMutex;
   std::mutex MKernelsPerProgramCacheMutex;
 
-  ProgramCache MCachedPrograms;
+  ProgramCacheT MCachedPrograms;
   KernelCacheT MKernelsPerProgramCache;
   ContextPtr MParentContext;