diff options
Diffstat (limited to 'lib/Transforms/Utils/SimplifyCFG.cpp')
-rw-r--r-- | lib/Transforms/Utils/SimplifyCFG.cpp | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp index 09f4fb2e13..f924eebb0d 100644 --- a/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/lib/Transforms/Utils/SimplifyCFG.cpp @@ -2211,17 +2211,28 @@ bool SimplifyCFGOpt::SimplifyUnreachable(UnreachableInst *UI) { // If the default value is unreachable, figure out the most popular // destination and make it the default. if (SI->getSuccessor(0) == BB) { - std::map<BasicBlock*, unsigned> Popularity; - for (unsigned i = 1, e = SI->getNumCases(); i != e; ++i) - Popularity[SI->getSuccessor(i)]++; - + std::map<BasicBlock*, std::pair<unsigned, unsigned> > Popularity; + for (unsigned i = 1, e = SI->getNumCases(); i != e; ++i) { + std::pair<unsigned, unsigned>& entry = + Popularity[SI->getSuccessor(i)]; + if (entry.first == 0) { + entry.first = 1; + entry.second = i; + } else { + entry.first++; + } + } + // Find the most popular block. unsigned MaxPop = 0; + unsigned MaxIndex = 0; BasicBlock *MaxBlock = 0; - for (std::map<BasicBlock*, unsigned>::iterator + for (std::map<BasicBlock*, std::pair<unsigned, unsigned> >::iterator I = Popularity.begin(), E = Popularity.end(); I != E; ++I) { - if (I->second > MaxPop) { - MaxPop = I->second; + if (I->second.first > MaxPop || + (I->second.first == MaxPop && MaxIndex > I->second.second)) { + MaxPop = I->second.first; + MaxIndex = I->second.second; MaxBlock = I->first; } } |