From: Kostya Serebryany <kcc@google.com>
Date: Tue, 8 Sep 2015 20:40:10 +0000 (+0000)
Subject: [libFuzzer] remove a piece of stale code
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=88d071c62640cd971b0eb750621b5353be54ee24

[libFuzzer] remove a piece of stale code

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247067 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Fuzzer/FuzzerTraceState.cpp b/lib/Fuzzer/FuzzerTraceState.cpp
index b7ed66fdfc6..34a98d1a20b 100644
--- a/lib/Fuzzer/FuzzerTraceState.cpp
+++ b/lib/Fuzzer/FuzzerTraceState.cpp
@@ -166,38 +166,6 @@ struct LabelRange {
   }
 };
 
-// A passport for a CMP site. We want to keep track of where the given CMP is
-// and how many times it is evaluated to true or false.
-struct CmpSitePassport {
-  uintptr_t PC;
-  size_t Counter[2];
-
-  bool IsInterestingCmpTarget() {
-    static const size_t kRareEnough = 50;
-    size_t C0 = Counter[0];
-    size_t C1 = Counter[1];
-    return C0 > kRareEnough * (C1 + 1) || C1 > kRareEnough * (C0 + 1);
-  }
-};
-
-// For now, just keep a simple imprecise hash table PC => CmpSitePassport.
-// Potentially, will need to have a compiler support to have a precise mapping
-// and also thread-safety.
-struct CmpSitePassportTable {
-  static const size_t kSize = 99991;  // Prime.
-  CmpSitePassport Passports[kSize];
-
-  CmpSitePassport *GetPassport(uintptr_t PC) {
-    uintptr_t Idx = PC & kSize;
-    CmpSitePassport *Res = &Passports[Idx];
-    if (Res->PC == 0)  // Not thread safe.
-      Res->PC = PC;
-    return Res->PC == PC ? Res : nullptr;
-  }
-};
-
-static CmpSitePassportTable CSPTable;  // Zero initialized.
-
 // For now, very simple: put Size bytes of Data at position Pos.
 struct TraceBasedMutation {
   size_t Pos;
@@ -349,16 +317,8 @@ void TraceState::TraceCmpCallback(uintptr_t PC, size_t CmpSize, size_t CmpType,
                                   uint64_t Arg1, uint64_t Arg2) {
   if (!RecordingTraces) return;
   int Added = 0;
-  CmpSitePassport *CSP = CSPTable.GetPassport(PC);
-  if (!CSP) return;
-  CSP->Counter[ComputeCmp(CmpSize, CmpType, Arg1, Arg2)]++;
-  size_t C0 = CSP->Counter[0];
-  size_t C1 = CSP->Counter[1];
-  // FIXME: is this a good idea or a bad?
-  // if (!CSP->IsInterestingCmpTarget())
-  //  return;
   if (Options.Verbosity >= 3)
-    Printf("TraceCmp: %p %zd/%zd; %zd %zd\n", CSP->PC, C0, C1, Arg1, Arg2);
+    Printf("TraceCmp %zd/%zd: %p %zd %zd\n", CmpSize, CmpType, PC, Arg1, Arg2);
   Added += TryToAddDesiredData(Arg1, Arg2, CmpSize);
   Added += TryToAddDesiredData(Arg2, Arg1, CmpSize);
   if (!Added && CmpSize == 4 && IsTwoByteData(Arg1) && IsTwoByteData(Arg2)) {