From ce1a3a292d7696c973efe27809384d33a530dd65 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Mon, 12 Apr 2004 05:37:29 +0000
Subject: [PATCH] Actually update the call graph as the inliner changes it. 
 This allows us to execute other CallGraphSCCPasses after the inliner without
 crashing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12861 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/IPO/Inliner.cpp | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/lib/Transforms/IPO/Inliner.cpp b/lib/Transforms/IPO/Inliner.cpp
index 808d3930b60..8633a7e950f 100644
--- a/lib/Transforms/IPO/Inliner.cpp
+++ b/lib/Transforms/IPO/Inliner.cpp
@@ -93,7 +93,21 @@ bool Inliner::runOnSCC(const std::vector<CallGraphNode*> &SCC) {
         // Attempt to inline the function...
         if (InlineFunction(CS)) {
           ++NumInlined;
+
+          // Update the call graph by deleting the edge from Callee to Caller
+          CallGraphNode *CalleeNode = CG[Callee];
+          CallGraphNode *CallerNode = CG[Caller];
+          CallerNode->removeCallEdgeTo(CalleeNode);
+
+          // Since we inlined all uninlinable call sites in the callee into the
+          // caller, add edges from the caller to all of the callees of the
+          // callee.
+          for (CallGraphNode::iterator I = CalleeNode->begin(),
+                 E = CalleeNode->end(); I != E; ++I)
+            CallerNode->addCalledFunction(*I);
   
+          // If the only remaining use of the function is a dead constant
+          // pointer ref, remove it.
           if (Callee->hasOneUse())
             if (ConstantPointerRef *CPR =
                 dyn_cast<ConstantPointerRef>(Callee->use_back()))
@@ -110,7 +124,12 @@ bool Inliner::runOnSCC(const std::vector<CallGraphNode*> &SCC) {
             if (I != SCCFunctions.end())    // Remove function from this SCC.
               SCCFunctions.erase(I);
 
-            Callee->getParent()->getFunctionList().erase(Callee);
+            // Remove any call graph edges from the callee to its callees.
+            while (CalleeNode->begin() != CalleeNode->end())
+              CalleeNode->removeCallEdgeTo(*(CalleeNode->end()-1));
+
+            // Removing the node for callee from the call graph and delete it.
+            delete CG.removeFunctionFromModule(CalleeNode);
             ++NumDeleted;
           }
           Changed = true;