Improve RefreshCallGraph to remove invalid call graph edge.

With commit r219944, InstCombine can now turn a sqrtl into a llvm.fabs.f64.
The call graph edge originally representing the call to sqrtl becomes invalid.
This patch modifies CGPassManager::RefreshCallGraph() to remove the invalid
call graph edge, which can triggers an assert in
CallGraphNode::addCalledFunction().

Phabricator Review: http://reviews.llvm.org/D7705
Patch by Lawrence Hu <lawrence@codeaurora.org>.

llvm-svn: 234902

1 files changed, 7 insertions, 4 deletions

diff --git a/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp b/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp
index 9d607cc0e4f..65ba1c7c6c4 100644
--- a/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp
+++ b/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp
@@ -212,10 +212,13 @@ bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC,
           // list of the same call.
           CallSites.count(I->first) ||
 
-          // If the call edge is not from a call or invoke, then the function
-          // pass RAUW'd a call with another value.  This can happen when
-          // constant folding happens of well known functions etc.
-          !CallSite(I->first)) {
+          // If the call edge is not from a call or invoke, or it is a
+          // instrinsic call, then the function pass RAUW'd a call with 
+          // another value. This can happen when constant folding happens
+          // of well known functions etc.
+          !CallSite(I->first) ||
+           (CallSite(I->first).getCalledFunction() &&
+            CallSite(I->first).getCalledFunction()->isIntrinsic())) {
         assert(!CheckingMode &&
                "CallGraphSCCPass did not update the CallGraph correctly!");