[llvm] [AMDGPU] Ensure positive InstOffset for buffer operations (PR #145504)

[Matt Arsenault via llvm-commits]

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@@ -803,6 +803,21 @@ DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
     }
   }
 
+  // Validate buffer offset for GFX12+ - must be positive
+  if ((MCII->get(MI.getOpcode()).TSFlags &
+       (SIInstrFlags::MTBUF | SIInstrFlags::MUBUF)) &&
+      AMDGPU::isGFX12Plus(STI)) {
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arsenm wrote:

Avoid generation checks 

https://github.com/llvm/llvm-project/pull/145504