[SelectionDAG] Add getFltSemantics to MVT and EVT. NFC

This will be used to replace SelectionDAG::EVTToAPFloatSemantics

A similar method exists in IR's Type class.

Author: topperc

llvm/include/llvm/CodeGen/SelectionDAG.h

@@ -14,8 +14,6 @@
 #ifndef LLVM_CODEGEN_SELECTIONDAG_H
 #define LLVM_CODEGEN_SELECTIONDAG_H
 
-#include "llvm/ADT/APFloat.h"
-#include "llvm/ADT/APInt.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DenseSet.h"
@@ -1824,16 +1822,7 @@ class SelectionDAG {
   /// Returns an APFloat semantics tag appropriate for the given type. If VT is
   /// a vector type, the element semantics are returned.
   static const fltSemantics &EVTToAPFloatSemantics(EVT VT) {
-    switch (VT.getScalarType().getSimpleVT().SimpleTy) {
-    default: llvm_unreachable("Unknown FP format");
-    case MVT::f16:     return APFloat::IEEEhalf();
-    case MVT::bf16:    return APFloat::BFloat();
-    case MVT::f32:     return APFloat::IEEEsingle();
-    case MVT::f64:     return APFloat::IEEEdouble();
-    case MVT::f80:     return APFloat::x87DoubleExtended();
-    case MVT::f128:    return APFloat::IEEEquad();
-    case MVT::ppcf128: return APFloat::PPCDoubleDouble();
-    }
+    return VT.getFltSemantics();
   }
 
   /// Add a dbg_value SDNode. If SD is non-null that means the

llvm/include/llvm/CodeGen/ValueTypes.h

@@ -27,6 +27,7 @@ namespace llvm {
 
   class LLVMContext;
   class Type;
+  struct fltSemantics;
 
   /// Extended Value Type. Capable of holding value types which are not native
   /// for any processor (such as the i12345 type), as well as the types an MVT
@@ -512,6 +513,10 @@ namespace llvm {
       }
     };
 
+    /// Returns an APFloat semantics tag appropriate for the value type. If this
+    /// is a vector type, the element semantics are returned.
+    const fltSemantics &getFltSemantics() const;
+
   private:
     // Methods for handling the Extended-type case in functions above.
     // These are all out-of-line to prevent users of this header file

llvm/include/llvm/CodeGenTypes/MachineValueType.h

@@ -26,6 +26,7 @@
 namespace llvm {
 
   class Type;
+  struct fltSemantics;
   class raw_ostream;
 
   /// Machine Value Type. Every type that is supported natively by some
@@ -476,6 +477,10 @@ namespace llvm {
     /// to a concrete value type.
     static MVT getVT(Type *Ty, bool HandleUnknown = false);
 
+    /// Returns an APFloat semantics tag appropriate for the value type. If this
+    /// is a vector type, the element semantics are returned.
+    const fltSemantics &getFltSemantics() const;
+
   public:
     /// SimpleValueType Iteration
     /// @{

llvm/lib/CodeGen/ValueTypes.cpp

@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/CodeGen/ValueTypes.h"
+#include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Type.h"
@@ -289,6 +290,23 @@ EVT EVT::getEVT(Type *Ty, bool HandleUnknown){
   }
 }
 
+const fltSemantics &MVT::getFltSemantics() const {
+  switch (getScalarType().SimpleTy) {
+  default: llvm_unreachable("Unknown FP format");
+  case MVT::f16:     return APFloat::IEEEhalf();
+  case MVT::bf16:    return APFloat::BFloat();
+  case MVT::f32:     return APFloat::IEEEsingle();
+  case MVT::f64:     return APFloat::IEEEdouble();
+  case MVT::f80:     return APFloat::x87DoubleExtended();
+  case MVT::f128:    return APFloat::IEEEquad();
+  case MVT::ppcf128: return APFloat::PPCDoubleDouble();
+  }
+}
+
+const fltSemantics &EVT::getFltSemantics() const {
+  return getScalarType().getSimpleVT().getFltSemantics();
+}
+
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 void MVT::dump() const {
   print(dbgs());