From 19f75fc947493461a76a48c4488d2b756162d94d Mon Sep 17 00:00:00 2001
From: Evgeniy Stepanov <eugeni.stepanov@gmail.com>
Date: Tue, 3 Jun 2014 14:16:00 +0000
Subject: [PATCH] [asan] Fix coverage instrumentation with -asan-globals=0.

llvm-svn: 210103
---
 .../Instrumentation/AddressSanitizer.cpp           | 57 ++++++++++++----------
 .../Instrumentation/AddressSanitizer/coverage.ll   | 12 +++++
 2 files changed, 44 insertions(+), 25 deletions(-)

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 8d21108..aef1293 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -384,6 +384,7 @@ class AddressSanitizerModule : public ModulePass {
  private:
   void initializeCallbacks(Module &M);
 
+  bool InstrumentGlobals(IRBuilder<> &IRB, Module &M);
   bool ShouldInstrumentGlobal(GlobalVariable *G);
   void poisonOneInitializer(Function &GlobalInit, GlobalValue *ModuleName);
   void createInitializerPoisonCalls(Module &M, GlobalValue *ModuleName);
@@ -983,21 +984,7 @@ void AddressSanitizerModule::initializeCallbacks(Module &M) {
 // This function replaces all global variables with new variables that have
 // trailing redzones. It also creates a function that poisons
 // redzones and inserts this function into llvm.global_ctors.
-bool AddressSanitizerModule::runOnModule(Module &M) {
-  if (!ClGlobals) return false;
-
-  DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
-  if (!DLP)
-    return false;
-  DL = &DLP->getDataLayout();
-
-  BL.reset(SpecialCaseList::createOrDie(BlacklistFile));
-  if (BL->isIn(M)) return false;
-  C = &(M.getContext());
-  int LongSize = DL->getPointerSizeInBits();
-  IntptrTy = Type::getIntNTy(*C, LongSize);
-  Mapping = getShadowMapping(M, LongSize);
-  initializeCallbacks(M);
+bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M) {
   DynamicallyInitializedGlobals.Init(M);
 
   SmallVector<GlobalVariable *, 16> GlobalsToChange;
@@ -1007,16 +994,6 @@ bool AddressSanitizerModule::runOnModule(Module &M) {
       GlobalsToChange.push_back(&G);
   }
 
-  Function *CtorFunc = M.getFunction(kAsanModuleCtorName);
-  assert(CtorFunc);
-  IRBuilder<> IRB(CtorFunc->getEntryBlock().getTerminator());
-
-  if (ClCoverage > 0) {
-    Function *CovFunc = M.getFunction(kAsanCovName);
-    int nCov = CovFunc ? CovFunc->getNumUses() : 0;
-    IRB.CreateCall(AsanCovModuleInit, ConstantInt::get(IntptrTy, nCov));
-  }
-
   size_t n = GlobalsToChange.size();
   if (n == 0) return false;
 
@@ -1134,6 +1111,36 @@ bool AddressSanitizerModule::runOnModule(Module &M) {
   return true;
 }
 
+bool AddressSanitizerModule::runOnModule(Module &M) {
+  DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
+  if (!DLP)
+    return false;
+  DL = &DLP->getDataLayout();
+  BL.reset(SpecialCaseList::createOrDie(BlacklistFile));
+  C = &(M.getContext());
+  int LongSize = DL->getPointerSizeInBits();
+  IntptrTy = Type::getIntNTy(*C, LongSize);
+  Mapping = getShadowMapping(M, LongSize);
+  initializeCallbacks(M);
+
+  bool Changed = false;
+
+  Function *CtorFunc = M.getFunction(kAsanModuleCtorName);
+  assert(CtorFunc);
+  IRBuilder<> IRB(CtorFunc->getEntryBlock().getTerminator());
+
+  if (ClCoverage > 0) {
+    Function *CovFunc = M.getFunction(kAsanCovName);
+    int nCov = CovFunc ? CovFunc->getNumUses() : 0;
+    IRB.CreateCall(AsanCovModuleInit, ConstantInt::get(IntptrTy, nCov));
+    Changed = true;
+  }
+
+  if (ClGlobals && !BL->isIn(M)) Changed |= InstrumentGlobals(IRB, M);
+
+  return Changed;
+}
+
 void AddressSanitizer::initializeCallbacks(Module &M) {
   IRBuilder<> IRB(*C);
   // Create __asan_report* callbacks.
diff --git a/llvm/test/Instrumentation/AddressSanitizer/coverage.ll b/llvm/test/Instrumentation/AddressSanitizer/coverage.ll
index 7e0ef1c..79bb5c1 100644
--- a/llvm/test/Instrumentation/AddressSanitizer/coverage.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/coverage.ll
@@ -3,6 +3,18 @@
 ; RUN: opt < %s -asan -asan-module -asan-coverage=2 -S | FileCheck %s --check-prefix=CHECK2
 ; RUN: opt < %s -asan -asan-module -asan-coverage=2 -asan-coverage-block-threshold=10 -S | FileCheck %s --check-prefix=CHECK2
 ; RUN: opt < %s -asan -asan-module -asan-coverage=2 -asan-coverage-block-threshold=1  -S | FileCheck %s --check-prefix=CHECK1
+
+; RUN: opt < %s -asan -asan-module -asan-coverage=0 -asan-globals=0 -S | \
+; RUN:     FileCheck %s --check-prefix=CHECK0
+; RUN: opt < %s -asan -asan-module -asan-coverage=1 -asan-globals=0 -S | \
+; RUN:     FileCheck %s --check-prefix=CHECK1
+; RUN: opt < %s -asan -asan-module -asan-coverage=2 -asan-globals=0 -S | \
+; RUN:     FileCheck %s --check-prefix=CHECK2
+; RUN: opt < %s -asan -asan-module -asan-coverage=2 -asan-coverage-block-threshold=10 \
+; RUN:     -asan-globals=0 -S | FileCheck %s --check-prefix=CHECK2
+; RUN: opt < %s -asan -asan-module -asan-coverage=2 -asan-coverage-block-threshold=1 \
+; RUN:     -asan-globals=0 -S | FileCheck %s --check-prefix=CHECK1
+
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-unknown-linux-gnu"
 define void @foo(i32* %a) sanitize_address {
-- 
2.7.4