[Constant] Inline ConstantInt::getSigned

[craig.topper]

Summary

ConstantInt::getSigned calls ConstantInt::get with the IsSigned flag set to true.
That flag normally defaults to false.

For always signed constants the code base is not consistent about whether
it uses ConstantInt::getSigned or ConstantInt::get with IsSigned set to true.
And it's not clear how to decide which way to use.

By making getSigned inline, both ways should generate the same code in
the end.

[nikic]

LGTM

llvm/include/llvm/IR/Constants.h

 //===-- llvm/Constants.h - Constant class subclass definitions --*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
public:
   /// Get a ConstantInt for a specific value.
   static ConstantInt *get(IntegerType *Ty, uint64_t V, bool IsSigned = false);
 
   /// Return a ConstantInt with the specified value for the specified type. The
   /// value V will be canonicalized to a an unsigned APInt. Accessing it with
   /// either getSExtValue() or getZExtValue() will yield a correctly sized and
   /// signed value for the type Ty.
   /// Get a ConstantInt for a specific signed value.
-  static ConstantInt *getSigned(IntegerType *Ty, int64_t V);
-  static Constant *getSigned(Type *Ty, int64_t V);
+  static ConstantInt *getSigned(IntegerType *Ty, int64_t V) {
+    return get(Ty, V, true);
+  }
+  static Constant *getSigned(Type *Ty, int64_t V) {
+    return get(Ty, V, true);
+  }
 
   /// Return a ConstantInt with the specified value and an implied Type. The
   /// type is the integer type that corresponds to the bit width of the value.
   static ConstantInt *get(LLVMContext &Context, const APInt &V);
 
   /// Return a ConstantInt constructed from the string strStart with the given
   /// radix.
   static ConstantInt *get(IntegerType *Ty, StringRef Str, uint8_t Radix);

llvm/lib/IR/Constants.cpp

 //===-- Constants.cpp - Implement Constant nodes --------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
Constant *ConstantInt::get(Type *Ty, uint64_t V, bool isSigned) {
 
   return C;
 }
 
 ConstantInt *ConstantInt::get(IntegerType *Ty, uint64_t V, bool isSigned) {
   return get(Ty->getContext(), APInt(Ty->getBitWidth(), V, isSigned));
 }
 
-ConstantInt *ConstantInt::getSigned(IntegerType *Ty, int64_t V) {
-  return get(Ty, V, true);
-}
-
-Constant *ConstantInt::getSigned(Type *Ty, int64_t V) {
-  return get(Ty, V, true);
-}
-
 Constant *ConstantInt::get(Type *Ty, const APInt& V) {
   ConstantInt *C = get(Ty->getContext(), V);
   assert(C->getType() == Ty->getScalarType() &&
          "ConstantInt type doesn't match the type implied by its value!");
 
   // For vectors, broadcast the value.
   if (VectorType *VTy = dyn_cast<VectorType>(Ty))
     return ConstantVector::getSplat(VTy->getElementCount(), C);