llvm/CodeGen/IntrinsicLowering.h

0001 //===-- IntrinsicLowering.h - Intrinsic Function Lowering -------*- C++ -*-===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008 //
0009 // This file defines the IntrinsicLowering interface.  This interface allows
0010 // addition of domain-specific or front-end specific intrinsics to LLVM without
0011 // having to modify all of the C backend or interpreter.
0012 //
0013 //===----------------------------------------------------------------------===//
0014
0015 #ifndef LLVM_CODEGEN_INTRINSICLOWERING_H
0016 #define LLVM_CODEGEN_INTRINSICLOWERING_H
0017
0018 namespace llvm {
0019 class CallInst;
0020 class DataLayout;
0021
0022 class IntrinsicLowering {
0023   const DataLayout &DL;
0024
0025   bool Warned = false;
0026
0027 public:
0028   explicit IntrinsicLowering(const DataLayout &DL) : DL(DL) {}
0029
0030   /// Replace a call to the specified intrinsic function.
0031   /// If an intrinsic function must be implemented by the code generator
0032   /// (such as va_start), this function should print a message and abort.
0033   ///
0034   /// Otherwise, if an intrinsic function call can be lowered, the code to
0035   /// implement it (often a call to a non-intrinsic function) is inserted
0036   /// _after_ the call instruction and the call is deleted. The caller must
0037   /// be capable of handling this kind of change.
0038   void LowerIntrinsicCall(CallInst *CI);
0039
0040   /// Try to replace a call instruction with a call to a bswap intrinsic. Return
0041   /// false if the call is not a simple integer bswap.
0042   static bool LowerToByteSwap(CallInst *CI);
0043 };
0044 }
0045
0046 #endif