[asan] Don't check ODR violations for particular types of globals

Summary:
private and internal: should not trigger ODR at all.
unnamed_addr: current ODR checking approach fail and rereport false violation if
a linker merges such globals
linkonce_odr, weak_odr: could cause similar problems and they are already not
instrumented for ELF.

Reviewers: eugenis, kcc

Subscribers: kubamracek, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D55621

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@349015 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/asan-static-odr.cpp

@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,ALIAS1
+
+// No alias on Windows but indicators should work.
+// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-windows-msvc %s | FileCheck %s --check-prefixes=CHECK,ALIAS0
+
+static int global;
+
+int main() {
+  return global;
+}
+
+// CHECK-NOT: __odr_asan_gen
+// CHECK-NOT: private alias
+// CHECK: [[VAR:@.*global.*]] ={{.*}} global { i32, [60 x i8] } zeroinitializer, align 32
+// CHECK: @0 = internal global {{.*}} [[VAR]] to i64), {{.*}}, i64 -1 }]
+// CHECK: call void @__asan_register_globals(i64 ptrtoint ([1 x { i64, i64, i64, i64, i64, i64, i64, i64 }]* @0 to i64), i64 1)
+// CHECK: call void @__asan_unregister_globals(i64 ptrtoint ([1 x { i64, i64, i64, i64, i64, i64, i64, i64 }]* @0 to i64), i64 1)