[llvm] [AMDGPU] Add intrinsic for raw atomic buffer loads (PR #97707)

[Matt Arsenault via llvm-commits]

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@@ -1116,6 +1116,19 @@ class AMDGPURawBufferLoad<LLVMType data_ty = llvm_any_ty> : DefaultAttrsIntrinsi
 def int_amdgcn_raw_buffer_load_format : AMDGPURawBufferLoad<llvm_anyfloat_ty>;
 def int_amdgcn_raw_buffer_load : AMDGPURawBufferLoad;
 
+class AMDGPURawAtomicBufferLoad<LLVMType data_ty = llvm_any_ty> : Intrinsic <
+  [data_ty],
+  [llvm_v4i32_ty,     // rsrc(SGPR)
+   llvm_i32_ty,       // offset(VGPR/imm, included in bounds checking and swizzling)
+   llvm_i32_ty,       // soffset(SGPR/imm, excluded from bounds checking and swizzling)
+   llvm_i32_ty],      // auxiliary data (imm, cachepolicy     (bit 0 = glc,
+                      //                                       bit 1 = slc,
+                      //                                       bit 2 = dlc on gfx10+),
+                      //                      swizzled buffer (bit 3 = swz))
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arsenm wrote:

I was wondering if we should carry this as an operand bundle 

https://github.com/llvm/llvm-project/pull/97707