[profile] Add early checking to bypass node pointer update

llvm-svn: 270766

1 files changed, 8 insertions, 3 deletions

diff --git a/compiler-rt/lib/profile/InstrProfilingValue.c b/compiler-rt/lib/profile/InstrProfilingValue.c
index 08f91b35fd5..63b5e6fca15 100644
--- a/compiler-rt/lib/profile/InstrProfilingValue.c
+++ b/compiler-rt/lib/profile/InstrProfilingValue.c
@@ -103,16 +103,21 @@ static ValueProfNode *allocateOneNode(__llvm_profile_data *Data, uint32_t Index,
   if (!hasStaticCounters)
     return (ValueProfNode *)calloc(1, sizeof(ValueProfNode));
 
-  Node = COMPILER_RT_PTR_FETCH_ADD(ValueProfNode, CurrentVNode, 1);
-  if (Node >= EndVNode) {
+  /* Early check to avoid value wrapping around.  */
+  if (CurrentVNode >= EndVNode) {
     if (OutOfNodesWarnings++ < MAX_VP_WARNS) {
       PROF_WARN("Unable to track new values: %s. "
-                " Consider using option -mllvm -vp-counters-per-site=<n> to allocate more"
+                " Consider using option -mllvm -vp-counters-per-site=<n> to "
+                "allocate more"
                 " value profile counters at compile time. \n",
                 "Running out of static counters");
     }
     return 0;
   }
+  Node = COMPILER_RT_PTR_FETCH_ADD(ValueProfNode, CurrentVNode, 1);
+  if (Node >= EndVNode)
+    return 0;
+
   return Node;
 }