[llvm] [AMDGPU] Prevent folding of FMAC into FMAAK with two literals (PR #217438)

[Matt Arsenault via llvm-commits]

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@@ -3963,6 +3963,9 @@ bool SIInstrInfo::foldImmediate(MachineInstr &UseMI, MachineInstr &DefMI,
 
     // Added part is the constant: Use v_madak_{f16, f32}.
     if (Src2->isReg() && Src2->getReg() == Reg) {
+      if ((Src0->isImm() && !isInlineConstant(*Src0)) ||
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arsenm wrote:

This seems like it should be evaluated somewhere lower, preferably by checking isInlineConstant in the context of the exact instructions operands rather than just the contextless value 

https://github.com/llvm/llvm-project/pull/217438