[asan] call __asan_init from .preinit_array. This simplifies __asan_init vs malloc chicken-and-egg situation on Android and probably on other flavours of Linux. Patch by eugenis@google.com.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146284 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 83be31e..fdea1b5 100644
--- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -163,6 +163,8 @@
private:
+ void appendToPreinitArray(Module &M, Function *F);
+
uint64_t getAllocaSizeInBytes(AllocaInst *AI) {
Type *Ty = AI->getAllocatedType();
uint64_t SizeInBytes = TD->getTypeStoreSizeInBits(Ty) / 8;
@@ -563,6 +565,18 @@
return true;
}
+// .preinit_array is something that hapens before all other inits.
+// On systems where .preinit_array is honored, we will call __asan_init early.
+// On other systems this will make no effect.
+void AddressSanitizer::appendToPreinitArray(Module &M, Function *F) {
+ IRBuilder<> IRB(M.getContext());
+ GlobalVariable *Var =
+ new GlobalVariable(M, PointerType::getUnqual(F->getFunctionType()),
+ false, GlobalValue::PrivateLinkage,
+ F, "__asan_preinit_private");
+ Var->setSection(".preinit_array");
+}
+
// virtual
bool AddressSanitizer::runOnModule(Module &M) {
// Initialize the private fields. No one has accessed them before.
@@ -633,6 +647,7 @@
}
appendToGlobalCtors(M, AsanCtorFunction, 1 /*high priority*/);
+ appendToPreinitArray(M, AsanInitFunction);
return Res;
}