[llvm] [AMDGPU] Add VBUFFER encoding for gfx13 (PR #196262)

[Matt Arsenault via llvm-commits]

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@@ -359,9 +359,11 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
 
   bool hasAtomicCSub() const { return HasGFX10_BEncoding; }
 
-  bool hasMTBUFInsts() const { return !hasGFX1250Insts(); }
+  bool hasMTBUFInsts() const { return HasGFX13Insts || !hasGFX1250Insts(); }
 
-  bool hasFormattedMUBUFInsts() const { return !hasGFX1250Insts(); }
+  bool hasFormattedMUBUFInsts() const {
+    return HasGFX13Insts || !hasGFX1250Insts();
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arsenm wrote:

Should have a proper subtarget feature 

https://github.com/llvm/llvm-project/pull/196262