[llvm] [Offload] Make AMDGPU plugin handle empty allocation properly (PR #142383)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-backend-amdgpu

@llvm/pr-subscribers-offload

Author: Joseph Huber (jhuber6)

<details>
<summary>Changes</summary>

Summary:
`malloc(0)` and `free(nullptr)` are both defined by the standard but we
current trigger erros and assertions on them. Fix that so this works
with empty arguments.


---
Full diff: https://github.com/llvm/llvm-project/pull/142383.diff


1 Files Affected:

- (modified) offload/plugins-nextgen/amdgpu/src/rtl.cpp (+1-4) 


``````````diff
diff --git a/offload/plugins-nextgen/amdgpu/src/rtl.cpp b/offload/plugins-nextgen/amdgpu/src/rtl.cpp
index 2733796611d9b..abb83686151a2 100644
--- a/offload/plugins-nextgen/amdgpu/src/rtl.cpp
+++ b/offload/plugins-nextgen/amdgpu/src/rtl.cpp
@@ -420,7 +420,7 @@ struct AMDGPUMemoryManagerTy : public DeviceAllocatorTy {
     assert(PtrStorage && "Invalid pointer storage");
 
     *PtrStorage = MemoryManager->allocate(Size, nullptr);
-    if (*PtrStorage == nullptr)
+    if (Size && *PtrStorage == nullptr)
       return Plugin::error(ErrorCode::OUT_OF_RESOURCES,
                            "failure to allocate from AMDGPU memory manager");
 
@@ -429,8 +429,6 @@ struct AMDGPUMemoryManagerTy : public DeviceAllocatorTy {
 
   /// Release an allocation to be reused.
   Error deallocate(void *Ptr) {
-    assert(Ptr && "Invalid pointer");
-
     if (MemoryManager->free(Ptr))
       return Plugin::error(ErrorCode::UNKNOWN,
                            "failure to deallocate from AMDGPU memory manager");
@@ -1204,7 +1202,6 @@ struct AMDGPUStreamTy {
     ReleaseBufferArgsTy *Args = reinterpret_cast<ReleaseBufferArgsTy *>(Data);
     assert(Args && "Invalid arguments");
     assert(Args->MemoryManager && "Invalid memory manager");
-    assert(Args->Buffer && "Invalid buffer");
 
     // Release the allocation to the memory manager.
     return Args->MemoryManager->deallocate(Args->Buffer);

``````````

</details>


https://github.com/llvm/llvm-project/pull/142383