[OpenMP][NFC] Merge MemoryManager into PluginInterface (#73678)

Similar to #73677, there is no benefit from keeping MemoryManager
seperate; it's tied into the current design. Except the move I also
replaced the getenv call with our Env handling.

Author: jdoerfert

openmp/libomptarget/plugins-nextgen/CMakeLists.txt

@@ -47,7 +47,6 @@ if(CMAKE_SYSTEM_PROCESSOR MATCHES "${tmachine}$")
 
         LINK_LIBS
         PRIVATE
-        MemoryManager
         PluginInterface
         ${LIBOMPTARGET_DEP_LIBFFI_LIBRARIES}
         ${OPENMP_PTHREAD_LIB}

openmp/libomptarget/plugins-nextgen/amdgpu/CMakeLists.txt

@@ -80,7 +80,6 @@ add_llvm_library(omptarget.rtl.amdgpu SHARED
 
   LINK_LIBS
   PRIVATE
-  MemoryManager
   PluginInterface
   ${LIBOMPTARGET_DEP_LIBRARIES}
   ${OPENMP_PTHREAD_LIB}

openmp/libomptarget/plugins-nextgen/common/CMakeLists.txt

@@ -12,4 +12,3 @@
 
 add_subdirectory(OMPT)
 add_subdirectory(PluginInterface)
-add_subdirectory(MemoryManager)

openmp/libomptarget/plugins-nextgen/common/MemoryManager/CMakeLists.txt

@@ -52,7 +52,6 @@ endif()
 target_link_libraries(OMPT
   PUBLIC
     ${llvm_libs}
-    MemoryManager
 )
 
 # Define the TARGET_NAME and DEBUG_PREFIX.

openmp/libomptarget/plugins-nextgen/common/OMPT/CMakeLists.txt

@@ -63,7 +63,6 @@ endif()
 target_link_libraries(PluginInterface
   PUBLIC
     ${llvm_libs}
-    MemoryManager
 )
 
 # Include the RPC server from the `libc` project if availible.

openmp/libomptarget/plugins-nextgen/common/PluginInterface/CMakeLists.txt

@@ -10,8 +10,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_OPENMP_LIBOMPTARGET_PLUGINS_COMMON_MEMORYMANAGER_MEMORYMANAGER_H
-#define LLVM_OPENMP_LIBOMPTARGET_PLUGINS_COMMON_MEMORYMANAGER_MEMORYMANAGER_H
+#ifndef LLVM_OPENMP_LIBOMPTARGET_PLUGINS_COMMON_MEMORYMANAGER_H
+#define LLVM_OPENMP_LIBOMPTARGET_PLUGINS_COMMON_MEMORYMANAGER_H
 
 #include <cassert>
 #include <functional>
@@ -22,6 +22,8 @@
 #include <vector>
 
 #include "Debug.h"
+#include "Utilities.h"
+#include "omptarget.h"
 
 /// Base class of per-device allocator.
 class DeviceAllocatorTy {
@@ -322,16 +324,15 @@ class MemoryManagerTy {
   /// manager explicitly by setting the var to 0. If user doesn't specify
   /// anything, returns <0, true>.
   static std::pair<size_t, bool> getSizeThresholdFromEnv() {
-    size_t Threshold = 0;
-
-    if (const char *Env =
-            std::getenv("LIBOMPTARGET_MEMORY_MANAGER_THRESHOLD")) {
-      Threshold = std::stoul(Env);
-      if (Threshold == 0) {
-        DP("Disabled memory manager as user set "
-           "LIBOMPTARGET_MEMORY_MANAGER_THRESHOLD=0.\n");
-        return std::make_pair(0, false);
-      }
+    static llvm::omp::target::UInt32Envar MemoryManagerThreshold(
+        "LIBOMPTARGET_MEMORY_MANAGER_THRESHOLD", 0);
+
+    size_t Threshold = MemoryManagerThreshold.get();
+
+    if (MemoryManagerThreshold.isPresent() && Threshold == 0) {
+      DP("Disabled memory manager as user set "
+         "LIBOMPTARGET_MEMORY_MANAGER_THRESHOLD=0.\n");
+      return std::make_pair(0, false);
     }
 
     return std::make_pair(Threshold, true);
@@ -343,4 +344,4 @@ class MemoryManagerTy {
 constexpr const size_t MemoryManagerTy::BucketSize[];
 constexpr const int MemoryManagerTy::NumBuckets;
 
-#endif // LLVM_OPENMP_LIBOMPTARGET_PLUGINS_COMMON_MEMORYMANAGER_MEMORYMANAGER_H
+#endif // LLVM_OPENMP_LIBOMPTARGET_PLUGINS_COMMON_MEMORYMANAGER_H

openmp/libomptarget/plugins-nextgen/common/MemoryManager/MemoryManager.h renamed to openmp/libomptarget/plugins-nextgen/common/PluginInterface/MemoryManager.h

@@ -34,7 +34,6 @@ add_llvm_library(omptarget.rtl.cuda SHARED
   Object
 
   LINK_LIBS PRIVATE
-  MemoryManager
   PluginInterface
   ${OPENMP_PTHREAD_LIB}