From 2a25daa0a94a677c1143876953fa501c78a332d4 Mon Sep 17 00:00:00 2001 From: Chandler Carruth Date: Thu, 24 Apr 2014 21:19:30 +0000 Subject: [PATCH] [LCG] Switch a weird do/while loop that actually couldn't fail its condition into an obviously infinite loop with an assert about the degenerate condition. No functionality changed. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207147 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/LazyCallGraph.cpp | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/lib/Analysis/LazyCallGraph.cpp b/lib/Analysis/LazyCallGraph.cpp index 3b727a5ee69..2e4fad3996e 100644 --- a/lib/Analysis/LazyCallGraph.cpp +++ b/lib/Analysis/LazyCallGraph.cpp @@ -444,7 +444,7 @@ LazyCallGraph::SCC *LazyCallGraph::getNextSCCInPostOrder() { DFSStack.push_back(std::make_pair(&N, N.begin())); } - do { + for (;;) { Node *N = DFSStack.back().first; assert(N->DFSNumber != 0 && "We should always assign a DFS number " "before placing a node onto the stack."); @@ -479,16 +479,15 @@ LazyCallGraph::SCC *LazyCallGraph::getNextSCCInPostOrder() { // Form the new SCC out of the top of the DFS stack. return formSCC(N, PendingSCCStack); + assert(!DFSStack.empty() && "We never found a viable root!"); + // At this point we know that N cannot ever be an SCC root. Its low-link // is not its dfs-number, and we've processed all of its children. It is // just sitting here waiting until some node further down the stack gets // low-link == dfs-number and pops it off as well. Move it to the pending // stack which is pulled into the next SCC to be formed. PendingSCCStack.push_back(N); - } while (!DFSStack.empty()); - - llvm_unreachable( - "We cannot reach the bottom of the stack without popping an SCC."); + } } char LazyCallGraphAnalysis::PassID; -- 2.34.1