From 5f07a8b312e9d4ca0142b05ebb1ef088d88b4770 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Fri, 14 Feb 2003 06:28:00 +0000 Subject: - Eliminate provably non-pointer nodes from graphs. This helps a lot of testcases, for example: New Time New #Nodes Old Time Old #Nodes 254.gap: 91.1024 21605 91.1397 22657 povray31: 2.7807 8613 3.0152 10338 255.vortex: 1.2034 8153 1.2172 8822 moria: .6756 3150 .7054 3877 300.twolf: .1652 2010 .1851 3270 Typically, testcases which use long and ulong integers a lot get better, f.e. povray above. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5566 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/DataStructure/DataStructure.cpp | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) (limited to 'lib/Analysis/DataStructure/DataStructure.cpp') diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp index f2817623d2..6371196c1f 100644 --- a/lib/Analysis/DataStructure/DataStructure.cpp +++ b/lib/Analysis/DataStructure/DataStructure.cpp @@ -1039,12 +1039,29 @@ void DSGraph::removeDeadNodes(unsigned Flags) { // Mark all nodes reachable by (non-global) scalar nodes as alive... for (hash_map::iterator I = ScalarMap.begin(), - E = ScalarMap.end(); I != E; ++I) - if (!isa(I->first)) - I->second.getNode()->markReachableNodes(Alive); - else { // Keep track of global nodes - GlobalNodes.push_back(std::make_pair(I->first, I->second.getNode())); + E = ScalarMap.end(); I != E; ) + if (isa(I->first)) { // Keep track of global nodes assert(I->second.getNode() && "Null global node?"); + GlobalNodes.push_back(std::make_pair(I->first, I->second.getNode())); + ++I; + } else { + // Check to see if this is a worthless node generated for non-pointer + // values, such as integers. Consider an addition of long types: A+B. + // Assuming we can track all uses of the value in this context, and it is + // NOT used as a pointer, we can delete the node. We will be able to + // detect this situation if the node pointed to ONLY has Unknown bit set + // in the node. In this case, the node is not incomplete, does not point + // to any other nodes (no mod/ref bits set), and is therefore + // uninteresting for data structure analysis. If we run across one of + // these, prune the scalar pointing to it. + // + DSNode *N = I->second.getNode(); + if (N->NodeType == DSNode::UnknownNode && !isa(I->first)) { + ScalarMap.erase(I++); + } else { + I->second.getNode()->markReachableNodes(Alive); + ++I; + } } // The return value is alive as well... -- cgit v1.2.3-18-g5258