[llvm] [AMDGPU] RewriteMFMAFormStage: pre-check dst/src2 eligibility in initHeuristics() (PR #199825)

[Shilei Tian via llvm-commits]

================
@@ -2307,10 +2307,18 @@ bool RewriteMFMAFormStage::initHeuristics(
       int ReplacementOp = AMDGPU::getMFMASrcCVDstAGPROp(MI.getOpcode());
       assert(ReplacementOp != -1);
 
+      MachineOperand *Src2 = TII->getNamedOperand(MI, AMDGPU::OpName::src2);
+      MachineOperand &Dst = MI.getOperand(0);
+      assert(Src2);
----------------
shiltian wrote:

No need for assert here. It should never fail.

https://github.com/llvm/llvm-project/pull/199825