[llvm] [offload][omp] Move reading _kernel_environment to libomptarget (PR #222606)

[Alex Duran via llvm-commits]

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@@ -459,8 +463,65 @@ static int loadImagesOntoDevice(DeviceTy &Device) {
               REPORT() << "Failed to write symbol for USM " << Entry.SymbolName;
         } else if (Entry.Address) {
           if (Device.RTL->get_function(Binary, Entry.SymbolName,
-                                       &DeviceEntry.Address) != OFFLOAD_SUCCESS)
+                                       &DeviceEntry.Address) !=
+              OFFLOAD_SUCCESS) {
             REPORT() << "Failed to load kernel " << Entry.SymbolName;
+          } else {
+            // Read this kernel's launch-geometry properties once, from its
+            // "<name>_kernel_environment" device global, and cache them on
+            // the device for use at launch time.
+
+            SmallString<128> EnvName(Entry.SymbolName);
+            EnvName += "_kernel_environment";
+            KernelEnvironmentTy KernelEnv{};
+            void *KernelEnvPtr = nullptr;
+            bool ReadOk =
+                Device.RTL->get_global(Binary, sizeof(KernelEnv),
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adurang wrote:

Not a particular one, but get_global is used in other places in the library currently.

https://github.com/llvm/llvm-project/pull/222606