[asan] Rename the ABI versioning symbol to '__asan_version_mismatch_check' instead of abusing '__asan_init'

We currently version `__asan_init` and when the ABI version doesn't match, the linker gives a `undefined reference to '__asan_init_v5'` message. From this, it might not be obvious that it's actually a version mismatch error. This patch makes the error message much clearer by changing the name of the undefined symbol to be `__asan_version_mismatch_check_xxx` (followed by the version string). We obviously don't want the initializer to be named like that, so it's a separate symbol that is used only for the purpose of version checking.

Reviewed at http://reviews.llvm.org/D11004

llvm-svn: 243003

4 files changed, 19 insertions, 7 deletions

diff --git a/llvm/include/llvm/Transforms/Utils/ModuleUtils.h b/llvm/include/llvm/Transforms/Utils/ModuleUtils.h
index 622265bae14..0f23d34de5d 100644
--- a/llvm/include/llvm/Transforms/Utils/ModuleUtils.h
+++ b/llvm/include/llvm/Transforms/Utils/ModuleUtils.h
@@ -15,6 +15,7 @@
 #define LLVM_TRANSFORMS_UTILS_MODULEUTILS_H
 
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/StringRef.h"
 #include <utility> // for std::pair
 
 namespace llvm {
@@ -56,7 +57,8 @@ Function *checkSanitizerInterfaceFunction(Constant *FuncOrBitcast);
 /// respectively.
 std::pair<Function *, Function *> createSanitizerCtorAndInitFunctions(
     Module &M, StringRef CtorName, StringRef InitName,
-    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs);
+    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs,
+    StringRef VersionCheckName = StringRef());
 } // End llvm namespace
 
 #endif //  LLVM_TRANSFORMS_UTILS_MODULEUTILS_H
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index c7f3cfb8a48..5dde5fed0d2 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -91,7 +91,9 @@ static const char *const kAsanUnregisterGlobalsName =
     "__asan_unregister_globals";
 static const char *const kAsanPoisonGlobalsName = "__asan_before_dynamic_init";
 static const char *const kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init";
-static const char *const kAsanInitName = "__asan_init_v5";
+static const char *const kAsanInitName = "__asan_init";
+static const char *const kAsanVersionCheckName =
+    "__asan_version_mismatch_check_v6";
 static const char *const kAsanPtrCmp = "__sanitizer_ptr_cmp";
 static const char *const kAsanPtrSub = "__sanitizer_ptr_sub";
 static const char *const kAsanHandleNoReturnName = "__asan_handle_no_return";
@@ -1468,9 +1470,9 @@ bool AddressSanitizer::doInitialization(Module &M) {
 
   if (!CompileKernel) {
     std::tie(AsanCtorFunction, AsanInitFunction) =
-        createSanitizerCtorAndInitFunctions(M, kAsanModuleCtorName, kAsanInitName,
-                                            /*InitArgTypes=*/{},
-                                            /*InitArgs=*/{});
+        createSanitizerCtorAndInitFunctions(
+            M, kAsanModuleCtorName, kAsanInitName,
+            /*InitArgTypes=*/{}, /*InitArgs=*/{}, kAsanVersionCheckName);
     appendToGlobalCtors(M, AsanCtorFunction, kAsanCtorAndDtorPriority);
   }
   Mapping = getShadowMapping(TargetTriple, LongSize, CompileKernel);
diff --git a/llvm/lib/Transforms/Utils/ModuleUtils.cpp b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
index d69a81ec474..c5abf76d93f 100644
--- a/llvm/lib/Transforms/Utils/ModuleUtils.cpp
+++ b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
@@ -107,7 +107,8 @@ Function *llvm::checkSanitizerInterfaceFunction(Constant *FuncOrBitcast) {
 
 std::pair<Function *, Function *> llvm::createSanitizerCtorAndInitFunctions(
     Module &M, StringRef CtorName, StringRef InitName,
-    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs) {
+    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs,
+    StringRef VersionCheckName) {
   assert(!InitName.empty() && "Expected init function name");
   assert(InitArgTypes.size() == InitArgTypes.size() &&
          "Sanitizer's init function expects different number of arguments");
@@ -122,6 +123,13 @@ std::pair<Function *, Function *> llvm::createSanitizerCtorAndInitFunctions(
           AttributeSet()));
   InitFunction->setLinkage(Function::ExternalLinkage);
   IRB.CreateCall(InitFunction, InitArgs);
+  if (!VersionCheckName.empty()) {
+    Function *VersionCheckFunction =
+        checkSanitizerInterfaceFunction(M.getOrInsertFunction(
+            VersionCheckName, FunctionType::get(IRB.getVoidTy(), {}, false),
+            AttributeSet()));
+    IRB.CreateCall(VersionCheckFunction, {});
+  }
   return std::make_pair(Ctor, InitFunction);
 }
 
diff --git a/llvm/test/Instrumentation/AddressSanitizer/basic.ll b/llvm/test/Instrumentation/AddressSanitizer/basic.ll
index 2490510fc76..9c4d416a1ef 100644
--- a/llvm/test/Instrumentation/AddressSanitizer/basic.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/basic.ll
@@ -171,7 +171,7 @@ define void @memintr_test(i8* %a, i8* %b) nounwind uwtable sanitize_address {
 ; CHECK: ret void
 
 ; CHECK: define internal void @asan.module_ctor()
-; CHECK: call void @__asan_init_v5()
+; CHECK: call void @__asan_init()
 
 ; PROF
 ; CHECK: ![[PROF]] = !{!"branch_weights", i32 1, i32 100000}