[compiler-rt] r270766 - [profile] Add early checking to bypass node pointer update

[Xinliang David Li via llvm-commits]

Author: davidxl
Date: Wed May 25 16:27:02 2016
New Revision: 270766

URL: http://llvm.org/viewvc/llvm-project?rev=270766&view=rev
Log:
[profile] Add early checking to bypass node pointer update

Modified:
    compiler-rt/trunk/lib/profile/InstrProfilingValue.c
    compiler-rt/trunk/test/profile/instrprof-value-prof.test

Modified: compiler-rt/trunk/lib/profile/InstrProfilingValue.c
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/profile/InstrProfilingValue.c?rev=270766&r1=270765&r2=270766&view=diff
==============================================================================
--- compiler-rt/trunk/lib/profile/InstrProfilingValue.c (original)
+++ compiler-rt/trunk/lib/profile/InstrProfilingValue.c Wed May 25 16:27:02 2016
@@ -103,16 +103,21 @@ static ValueProfNode *allocateOneNode(__
   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;
 }
 

Modified: compiler-rt/trunk/test/profile/instrprof-value-prof.test
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/profile/instrprof-value-prof.test?rev=270766&r1=270765&r2=270766&view=diff
==============================================================================
--- compiler-rt/trunk/test/profile/instrprof-value-prof.test (original)
+++ compiler-rt/trunk/test/profile/instrprof-value-prof.test Wed May 25 16:27:02 2016
@@ -11,6 +11,9 @@
 // RUN: llvm-profdata merge -text  %t.ir.profdata -o %t.ir.proftxt 
 // RUN: FileCheck  %S/Inputs/instrprof-value-prof-real.c --check-prefix=IR < %t.ir.proftxt
 
+// RUN: %clang_profgen -O2 -mllvm -disable-vp=false -Xclang -fprofile-instrument=llvm -mllvm -vp-static-alloc=true -o %t.ir.warn  %S/Inputs/instrprof-value-prof-real.c
+// RUN: env LLVM_PROFILE_FILE=%t.ir.profraw %run %t.ir.warn 2>&1 |FileCheck --check-prefix=WARNING %s
+
 // IR level instrumentation with dynamic memory allocation
 // RUN: %clang_profgen -O2 -mllvm -disable-vp=false -Xclang -fprofile-instrument=llvm -mllvm -vp-static-alloc=false -mllvm -vp-counters-per-site=256 -o %t.ir.dyn  %S/Inputs/instrprof-value-prof-real.c
 // RUN: env LLVM_PROFILE_FILE=%t.ir.dyn.profraw %run %t.ir.dyn
@@ -18,3 +21,5 @@
 // RUN: llvm-profdata show --all-functions -ic-targets  %t.ir.dyn.profdata | FileCheck  %S/Inputs/instrprof-value-prof-real.c
 // RUN: llvm-profdata merge -text  %t.ir.dyn.profdata -o %t.ir.dyn.proftxt 
 // RUN: FileCheck  %S/Inputs/instrprof-value-prof-real.c --check-prefix=IR < %t.ir.dyn.proftxt
+
+// WARNING: LLVM Profile Warning: