include/llvm/Transforms/Utils/CallPromotionUtils.h

   1 //===- CallPromotionUtils.h - Utilities for call promotion ------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file declares utilities useful for promoting indirect call sites to
  10 // direct call sites.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_TRANSFORMS_UTILS_CALLPROMOTIONUTILS_H
  15 #define LLVM_TRANSFORMS_UTILS_CALLPROMOTIONUTILS_H
  16
  17 #include "llvm/IR/CallSite.h"
  18
  19 namespace llvm {
  20
  21 /// Return true if the given indirect call site can be made to call \p Callee.
  22 ///
  23 /// This function ensures that the number and type of the call site's arguments
  24 /// and return value match those of the given function. If the types do not
  25 /// match exactly, they must at least be bitcast compatible. If \p FailureReason
  26 /// is non-null and the indirect call cannot be promoted, the failure reason
  27 /// will be stored in it.
  28 bool isLegalToPromote(CallSite CS, Function *Callee,
  29                       const char **FailureReason = nullptr);
  30
  31 /// Promote the given indirect call site to unconditionally call \p Callee.
  32 ///
  33 /// This function promotes the given call site, returning the direct call or
  34 /// invoke instruction. If the function type of the call site doesn't match that
  35 /// of the callee, bitcast instructions are inserted where appropriate. If \p
  36 /// RetBitCast is non-null, it will be used to store the return value bitcast,
  37 /// if created.
  38 Instruction *promoteCall(CallSite CS, Function *Callee,
  39                          CastInst **RetBitCast = nullptr);
  40
  41 /// Promote the given indirect call site to conditionally call \p Callee.
  42 ///
  43 /// This function creates an if-then-else structure at the location of the call
  44 /// site. The original call site is moved into the "else" block. A clone of the
  45 /// indirect call site is promoted, placed in the "then" block, and returned. If
  46 /// \p BranchWeights is non-null, it will be used to set !prof metadata on the
  47 /// new conditional branch.
  48 Instruction *promoteCallWithIfThenElse(CallSite CS, Function *Callee,
  49                                        MDNode *BranchWeights = nullptr);
  50
  51 } // end namespace llvm
  52
  53 #endif // LLVM_TRANSFORMS_UTILS_CALLPROMOTIONUTILS_H