diff options
| -rw-r--r-- | include/llvm/Analysis/Dominators.h | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/include/llvm/Analysis/Dominators.h b/include/llvm/Analysis/Dominators.h index 76f9111b8d..a6df556051 100644 --- a/include/llvm/Analysis/Dominators.h +++ b/include/llvm/Analysis/Dominators.h @@ -1,4 +1,4 @@ -//===- llvm/Analysis/Dominators.h - Dominator Info Calculation ---*- C++ -*--=// +//===- llvm/Analysis/Dominators.h - Dominator Info Calculation --*- C++ -*-===// // // This file defines the following classes: // 1. DominatorSet: Calculates the [reverse] dominator set for a function @@ -46,7 +46,9 @@ public: //===----------------------------------------------------------------------===// // // DominatorSet - Maintain a set<BasicBlock*> for every basic block in a -// function, that represents the blocks that dominate the block. +// function, that represents the blocks that dominate the block. If the block +// is unreachable in this function, the set will be empty. This cannot happen +// for reachable code, because every block dominates at least itself. // class DominatorSetBase : public DominatorBase { public: @@ -80,6 +82,12 @@ public: return I->second; } + /// isReachable - Return true if the specified basicblock is reachable. If + /// the block is reachable, we have dominator set information for it. + bool isReachable(BasicBlock *BB) const { + return !getDominators(BB).empty(); + } + /// dominates - Return true if A dominates B. /// inline bool dominates(BasicBlock *A, BasicBlock *B) const { |