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

[Jay Foad via llvm-commits]

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@@ -4464,12 +4464,13 @@ bool AMDGPUAsmParser::validateOffset(const MCInst &Inst,
     return validateSMEMOffset(Inst, Operands);
 
   const auto &Op = Inst.getOperand(OpNum);
+  // GFX12+ buffer ops: InstOffset is signed 24, but must be positive
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jayfoad wrote:

```suggestion
  // GFX12+ buffer ops: InstOffset is signed 24, but must not be negative.
```

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