[asancov] Don't emit extra runtime calls when compiling without coverage.

llvm-svn: 209721

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 95fca75..f8cdb9f 100644 (file)
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -1030,9 +1030,11 @@ bool AddressSanitizerModule::runOnModule(Module &M) {
   assert(CtorFunc);
   IRBuilder<> IRB(CtorFunc->getEntryBlock().getTerminator());
 
-  Function *CovFunc = M.getFunction(kAsanCovName);
-  int nCov = CovFunc ? CovFunc->getNumUses() : 0;
-  IRB.CreateCall(AsanCovModuleInit, ConstantInt::get(IntptrTy, nCov));
+  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;

diff --git a/llvm/test/Instrumentation/AddressSanitizer/coverage.ll b/llvm/test/Instrumentation/AddressSanitizer/coverage.ll
index 5bc5103..7e0ef1c 100644 (file)
--- a/llvm/test/Instrumentation/AddressSanitizer/coverage.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/coverage.ll
@@ -1,3 +1,4 @@
+; RUN: opt < %s -asan -asan-module -asan-coverage=0 -S | FileCheck %s --check-prefix=CHECK0
 ; RUN: opt < %s -asan -asan-module -asan-coverage=1 -S | FileCheck %s --check-prefix=CHECK1
 ; 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
@@ -17,6 +18,9 @@ entry:
   ret void
 }
 
+; CHECK0-NOT: call void @__sanitizer_cov(
+; CHECK0-NOT: call void @__sanitizer_cov_module_init(
+
 ; CHECK1-LABEL: define void @foo
 ; CHECK1: %0 = load atomic i8* @__asan_gen_cov_foo monotonic, align 1
 ; CHECK1: %1 = icmp eq i8 0, %0