[llvm] [LoongArch] Lowering flog2 to flogb (PR #162978)

[via llvm-commits]

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@@ -188,6 +188,7 @@ def : PatFprFpr<fminnum, FMIN_S, FPR32>;
 def : PatFpr<fneg, FNEG_S, FPR32>;
 def : PatFpr<fabs, FABS_S, FPR32>;
 def : PatFpr<fsqrt, FSQRT_S, FPR32>;
+def : PatFpr<flog2, FLOGB_S, FPR32>;
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zhaoqi5 wrote:

We donot have `flogb.s/d` on LA32.

https://github.com/llvm/llvm-project/pull/162978