RISC-V: Select FCANONICALIZE (#112083)

We can use `FMIN.x OP,OP` to canonlize a float.

Author: wzssyqa

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -411,13 +411,13 @@ RISCVTargetLowering::RISCVTargetLowering(const TargetMachine &TM,
     setOperationAction(ISD::SELECT, XLenVT, Custom);
 
   static const unsigned FPLegalNodeTypes[] = {
-      ISD::FMINNUM,       ISD::FMAXNUM,       ISD::FMINIMUMNUM,
-      ISD::FMAXIMUMNUM,   ISD::LRINT,         ISD::LLRINT,
-      ISD::LROUND,        ISD::LLROUND,       ISD::STRICT_LRINT,
-      ISD::STRICT_LLRINT, ISD::STRICT_LROUND, ISD::STRICT_LLROUND,
-      ISD::STRICT_FMA,    ISD::STRICT_FADD,   ISD::STRICT_FSUB,
-      ISD::STRICT_FMUL,   ISD::STRICT_FDIV,   ISD::STRICT_FSQRT,
-      ISD::STRICT_FSETCC, ISD::STRICT_FSETCCS};
+      ISD::FMINNUM,       ISD::FMAXNUM,        ISD::FMINIMUMNUM,
+      ISD::FMAXIMUMNUM,   ISD::LRINT,          ISD::LLRINT,
+      ISD::LROUND,        ISD::LLROUND,        ISD::STRICT_LRINT,
+      ISD::STRICT_LLRINT, ISD::STRICT_LROUND,  ISD::STRICT_LLROUND,
+      ISD::STRICT_FMA,    ISD::STRICT_FADD,    ISD::STRICT_FSUB,
+      ISD::STRICT_FMUL,   ISD::STRICT_FDIV,    ISD::STRICT_FSQRT,
+      ISD::STRICT_FSETCC, ISD::STRICT_FSETCCS, ISD::FCANONICALIZE};
 
   static const ISD::CondCode FPCCToExpand[] = {
       ISD::SETOGT, ISD::SETOGE, ISD::SETONE, ISD::SETUEQ, ISD::SETUGT,
@@ -441,7 +441,7 @@ RISCVTargetLowering::RISCVTargetLowering(const TargetMachine &TM,
       ISD::STRICT_FSQRT, ISD::STRICT_FSETCC, ISD::STRICT_FSETCCS,
       ISD::SETCC,        ISD::FCEIL,         ISD::FFLOOR,
       ISD::FTRUNC,       ISD::FRINT,         ISD::FROUND,
-      ISD::FROUNDEVEN};
+      ISD::FROUNDEVEN,   ISD::FCANONICALIZE};
 
   if (Subtarget.hasStdExtZfbfmin()) {
     setOperationAction(ISD::BITCAST, MVT::i16, Custom);

llvm/lib/Target/RISCV/RISCVInstrInfoD.td

@@ -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)>;
 }
 
 /// Setcc

llvm/lib/Target/RISCV/RISCVInstrInfoF.td

@@ -623,6 +623,7 @@ foreach Ext = FExts in {
   defm : PatFprFpr_m<fmaximumnum, FMAX_S, Ext>;
   defm : PatFprFpr_m<riscv_fmin, FMIN_S, Ext>;
   defm : PatFprFpr_m<riscv_fmax, FMAX_S, Ext>;
+  def : Pat<(f32 (fcanonicalize FPR32:$rs1)), (FMIN_S $rs1, $rs1)>;
 }
 
 /// Setcc

llvm/lib/Target/RISCV/RISCVInstrInfoZfh.td

@@ -369,6 +369,7 @@ foreach Ext = ZfhExts in {
   defm : PatFprFpr_m<fmaximumnum, FMAX_H, Ext>;
   defm : PatFprFpr_m<riscv_fmin, FMIN_H, Ext>;
   defm : PatFprFpr_m<riscv_fmax, FMAX_H, Ext>;
+  def : Pat<(f16 (fcanonicalize FPR16:$rs1)), (FMIN_H $rs1, $rs1)>;
 }
 
 /// Setcc