[llvm] [AMDGPU] Account for inline asm size in inst_pref_size calculation (PR #192306)

[Matt Arsenault via llvm-commits]

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@@ -34,6 +34,14 @@ struct MCKernelDescriptor {
   const MCExpr *kernel_code_properties = nullptr;
   const MCExpr *kernarg_preload = nullptr;
 
+  /// Instruction prefetch size, kept separate from compute_pgm_rsrc3 to avoid
+  /// contaminating the register MCExpr with an unresolvable label subtraction
+  /// (which would prevent text-mode printing of other fields in the register).
+  /// The ELF streamer OR's this into compute_pgm_rsrc3 when emitting bytes.
+  const MCExpr *inst_pref_size = nullptr;
+  uint32_t inst_pref_size_shift = 0;
+  uint32_t inst_pref_size_mask = 0;
+
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arsenm wrote:

This isn't a unique property of this field though 

https://github.com/llvm/llvm-project/pull/192306