[llvm] RISC-V: Select FCANONICALIZE (PR #112083)

[Matt Arsenault via llvm-commits]

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@@ -398,6 +398,7 @@ foreach Ext = DExts in {
   defm : PatFprFpr_m<fmaximumnum, FMAX_D, Ext>;
   defm : PatFprFpr_m<riscv_fmin, FMIN_D, Ext>;
   defm : PatFprFpr_m<riscv_fmax, FMAX_D, Ext>;
+  def : Pat<(f64 (fcanonicalize FPR64:$rs1)), (FMIN_D $rs1, $rs1)>;
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arsenm wrote:

Does this mean this is still unsupported without an extension? 

https://github.com/llvm/llvm-project/pull/112083