[llvm] [X86][SelectionDAG] - Add support for llvm.canonicalize intrinsic (PR #106370)

[Pawan Nirpal via llvm-commits]

================
@@ -58159,6 +58160,25 @@ static SDValue combineINTRINSIC_VOID(SDNode *N, SelectionDAG &DAG,
   return SDValue();
 }
 
+static SDValue combineCanonicalize(SDNode *N, SelectionDAG &DAG) {
+  SDValue Operand = N->getOperand(0);
+  EVT VT = Operand.getValueType();
+  SDLoc dl(N);
+
+  // Canonicalize scalar variable FP Nodes.
+  SDValue One =
+      DAG.getNode(ISD::SINT_TO_FP, dl, VT, DAG.getConstant(1, dl, MVT::i32));
----------------
pawan-nirpal-031 wrote:

Is this correct way of handling data types? f32, f64 , f16 and f80 as custom and for vector types custom or legal would result in a crash! 

```
@@ -331,9 +331,11 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
       setOperationAction(ISD::FP_TO_UINT_SAT, VT, Custom);
       setOperationAction(ISD::FP_TO_SINT_SAT, VT, Custom);
     }
+    setOperationAction(ISD::FCANONICALIZE, MVT::f32, Custom);
     if (Subtarget.is64Bit()) {
       setOperationAction(ISD::FP_TO_UINT_SAT, MVT::i64, Custom);
       setOperationAction(ISD::FP_TO_SINT_SAT, MVT::i64, Custom);
+      setOperationAction(ISD::FCANONICALIZE, MVT::f64, Custom);
     }
   }
 
@@ -708,6 +710,7 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
     setOperationAction(ISD::STRICT_FROUNDEVEN, MVT::f16, Promote);
     setOperationAction(ISD::STRICT_FTRUNC, MVT::f16, Promote);
     setOperationAction(ISD::STRICT_FP_ROUND, MVT::f16, Custom);
+    setOperationAction(ISD::FCANONICALIZE, MVT::f16, Custom);
     setOperationAction(ISD::STRICT_FP_EXTEND, MVT::f32, Custom);
     setOperationAction(ISD::STRICT_FP_EXTEND, MVT::f64, Custom);
 
@@ -924,6 +927,7 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine
 &TM,
     if (isTypeLegal(MVT::f80)) {
       setOperationAction(ISD::FP_ROUND, MVT::f80, Custom);
       setOperationAction(ISD::STRICT_FP_ROUND, MVT::f80, Custom);
+      setOperationAction(ISD::FCANONICALIZE, MVT::f80, Custom);
     }
 
     setOperationAction(ISD::SETCC, MVT::f128, Custom);
@@ -969,6 +973,7 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine
 &TM,
     setOperationAction(ISD::FEXP,      VT, Expand);
     setOperationAction(ISD::FEXP2,     VT, Expand);
     setOperationAction(ISD::FEXP10,    VT, Expand);
+    setOperationAction(ISD::FCANONICALIZE, VT, Expand);
     // clang-format on
   }
 
```

https://github.com/llvm/llvm-project/pull/106370