[asan] make sure asan erases old unused allocas after it created a new one. This became important after the recent move from ModulePass to FunctionPass because no cleanup is happening after asan pass any more.
llvm-svn: 166267
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 75f42f3..d99bb87 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -1148,6 +1148,10 @@
}
}
+ // We are done. Remove the old unused alloca instructions.
+ for (size_t i = 0, n = AllocaVec.size(); i < n; i++)
+ AllocaVec[i]->eraseFromParent();
+
if (ClDebugStack) {
DEBUG(dbgs() << F);
}
diff --git a/llvm/test/Instrumentation/AddressSanitizer/basic.ll b/llvm/test/Instrumentation/AddressSanitizer/basic.ll
index d190001..655f69c 100644
--- a/llvm/test/Instrumentation/AddressSanitizer/basic.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/basic.ll
@@ -69,3 +69,23 @@
store i32 42, i32* %a
ret void
}
+
+; Check that asan leaves just one alloca.
+
+declare void @alloca_test_use([10 x i8]*)
+define void @alloca_test() address_safety {
+entry:
+ %x = alloca [10 x i8], align 1
+ %y = alloca [10 x i8], align 1
+ %z = alloca [10 x i8], align 1
+ call void @alloca_test_use([10 x i8]* %x)
+ call void @alloca_test_use([10 x i8]* %y)
+ call void @alloca_test_use([10 x i8]* %z)
+ ret void
+}
+
+; CHECK: define void @alloca_test()
+; CHECK: = alloca
+; CHECK-NOT: = alloca
+; CHECK: ret void
+