include/llvm/Transforms/Utils/EscapeEnumerator.h

   1 //===-- EscapeEnumerator.h --------------------------------------*- 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 // Defines a helper class that enumerates all possible exits from a function,
  10 // including exception handling.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_TRANSFORMS_UTILS_ESCAPEENUMERATOR_H
  15 #define LLVM_TRANSFORMS_UTILS_ESCAPEENUMERATOR_H
  16
  17 #include "llvm/IR/Function.h"
  18 #include "llvm/IR/IRBuilder.h"
  19
  20 namespace llvm {
  21
  22 /// EscapeEnumerator - This is a little algorithm to find all escape points
  23 /// from a function so that "finally"-style code can be inserted. In addition
  24 /// to finding the existing return and unwind instructions, it also (if
  25 /// necessary) transforms any call instructions into invokes and sends them to
  26 /// a landing pad.
  27 class EscapeEnumerator {
  28   Function &F;
  29   const char *CleanupBBName;
  30
  31   Function::iterator StateBB, StateE;
  32   IRBuilder<> Builder;
  33   bool Done;
  34   bool HandleExceptions;
  35
  36 public:
  37   EscapeEnumerator(Function &F, const char *N = "cleanup",
  38                    bool HandleExceptions = true)
  39       : F(F), CleanupBBName(N), StateBB(F.begin()), StateE(F.end()),
  40         Builder(F.getContext()), Done(false),
  41         HandleExceptions(HandleExceptions) {}
  42
  43   IRBuilder<> *Next();
  44 };
  45
  46 }
  47
  48 #endif // LLVM_TRANSFORMS_UTILS_ESCAPEENUMERATOR_H