[llvm] [AMDGPU] Add llvm.amdgcn.s.prefetch.inst intrinsic (PR #192440)

[Matt Arsenault via llvm-commits]

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@@ -3195,6 +3195,14 @@ def int_amdgcn_s_prefetch_data :
     "", [SDNPMemOperand]
   >;
 
+def int_amdgcn_s_prefetch_inst :
+  Intrinsic<[],
+  [LLVMQualPointerType<4>, // Pointer to constant memory
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arsenm wrote:

Given we never made the change to put programs into the constant address space, the normal usage would be a flat pointer?

https://github.com/llvm/llvm-project/pull/192440