[GlobalISel] Add missing file in previous commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260923 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/GlobalISel/CallLowering.h

@@ -0,0 +1,72 @@
+//===-- llvm/CodeGen/GlobalISel/CallLowering.h - Call lowering --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file describes how to lower LLVM calls to machine code calls.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_GLOBALISEL_CALLLOWERING_H
+#define LLVM_CODEGEN_GLOBALISEL_CALLLOWERING_H
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/Function.h"
+
+namespace llvm {
+// Forward declarations.
+class MachineIRBuilder;
+class TargetLowering;
+class Value;
+
+class CallLowering {
+  const TargetLowering *TLI;
+ protected:
+  /// Getter for generic TargetLowering class.
+  const TargetLowering *getTLI() const {
+    return TLI;
+  }
+
+  /// Getter for target specific TargetLowering class.
+  template <class XXXTargetLowering>
+    const XXXTargetLowering *getTLI() const {
+    return static_cast<const XXXTargetLowering *>(TLI);
+  }
+ public:
+  CallLowering(const TargetLowering *TLI) : TLI(TLI) {}
+  virtual ~CallLowering() {}
+  
+  /// This hook must be implemented to lower outgoing return values, described
+  /// by \p Val, into the specified virtual register \p VReg.
+  /// This hook is used by GlobalISel.
+  ///
+  /// \return True if the lowering succeeds, false otherwise.
+  virtual bool LowerReturn(MachineIRBuilder &MIRBuilder, const Value *Val,
+                           unsigned VReg) const {
+    return false;
+  }
+
+  /// This hook must be implemented to lower the incoming (formal)
+  /// arguments, described by \p Args, for GlobalISel. Each argument
+  /// must end up in the related virtual register described by VRegs.
+  /// In other words, the first argument should end up in VRegs[0],
+  /// the second in VRegs[1], and so on.
+  /// \p MIRBuilder is set to the proper insertion for the argument
+  /// lowering.
+  ///
+  /// \return True if the lowering succeeded, false otherwise.
+  virtual bool
+  LowerFormalArguments(MachineIRBuilder &MIRBuilder,
+                       const Function::ArgumentListType &Args,
+                       const SmallVectorImpl<unsigned> &VRegs) const {
+    return false;
+  }
+};
+} // End namespace llvm.
+
+#endif