[llvm] [GlobalISel] Handle div-by-pow2 (PR #83155)

[Shilei Tian via llvm-commits]

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@@ -5286,6 +5286,156 @@ MachineInstr *CombinerHelper::buildSDivUsingMul(MachineInstr &MI) {
   return MIB.buildMul(Ty, Res, Factor);
 }
 
+bool CombinerHelper::matchDivByPow2(MachineInstr &MI, bool IsSigned) {
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shiltian wrote:

I'll see how to use `MatchData` later.

https://github.com/llvm/llvm-project/pull/83155