From fc6e69bcb2c8b9157164adfaa0c86115e7356cd0 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 15 Mar 2010 16:37:42 +0000 Subject: don't eliminate address-taken blocks here. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98550 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/UnreachableBlockElim.cpp | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'lib/CodeGen/UnreachableBlockElim.cpp') diff --git a/lib/CodeGen/UnreachableBlockElim.cpp b/lib/CodeGen/UnreachableBlockElim.cpp index 7b338126d4..c0d4494d5b 100644 --- a/lib/CodeGen/UnreachableBlockElim.cpp +++ b/lib/CodeGen/UnreachableBlockElim.cpp @@ -58,13 +58,25 @@ FunctionPass *llvm::createUnreachableBlockEliminationPass() { return new UnreachableBlockElim(); } +static void MarkReachableFrom(BasicBlock *BB, + SmallPtrSet &Reachable) { + for (df_ext_iterator > I = + df_ext_begin(BB, Reachable), E = df_ext_end(BB, Reachable); I != E; ++I) + ; // Mark all reachable blocks. +} + bool UnreachableBlockElim::runOnFunction(Function &F) { SmallPtrSet Reachable; // Mark all reachable blocks. - for (df_ext_iterator > I = - df_ext_begin(&F, Reachable), E = df_ext_end(&F, Reachable); I != E; ++I) - /* Mark all reachable blocks */; + MarkReachableFrom(&F.getEntryBlock(), Reachable); + + // Mark any address-taken blocks. We don't want codegen to delete these + // because the address may already be referenced by another function and the + // label may be referenced. + for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) + if (I->hasAddressTaken() && !Reachable.count(I)) + MarkReachableFrom(I, Reachable); // Loop over all dead blocks, remembering them and deleting all instructions // in them. -- cgit v1.2.3