[llvm] [AMDGPU] MCExpr printing helper with KnownBits support (PR #95951)

[Matt Arsenault via llvm-commits]

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@@ -314,3 +315,142 @@ AMDGPUVariadicMCExpr::createOccupancy(unsigned InitOcc, const MCExpr *NumSGPRs,
                  CreateExpr(InitOcc), NumSGPRs, NumVGPRs},
                 Ctx);
 }
+
+static KnownBits AMDGPUMCExprKnownBits(const MCExpr *Expr, raw_ostream &OS,
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arsenm wrote:

This is a lot fancier than I would expect we need for this 

https://github.com/llvm/llvm-project/pull/95951