1 files changed, 90 insertions, 0 deletions
diff --git a/test/asan/TestCases/Linux/swapcontext_test.cc b/test/asan/TestCases/Linux/swapcontext_test.cc
new file mode 100644
index 000000000000..86ed5930bcf4
--- /dev/null
+++ b/test/asan/TestCases/Linux/swapcontext_test.cc
@@ -0,0 +1,90 @@
+// Check that ASan plays well with easy cases of makecontext/swapcontext.
+
+// RUN: %clangxx_asan -O0 %s -o %t && %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_asan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_asan -O2 %s -o %t && %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_asan -O3 %s -o %t && %run %t 2>&1 | FileCheck %s
+//
+// This test is too sublte to try on non-x86 arch for now.
+// REQUIRES: x86_64-supported-target,i386-supported-target
+
+#include <stdio.h>
+#include <ucontext.h>
+#include <unistd.h>
+
+ucontext_t orig_context;
+ucontext_t child_context;
+
+const int kStackSize = 1 << 20;
+
+__attribute__((noinline))
+void Throw() {
+  throw 1;
+}
+
+__attribute__((noinline))
+void ThrowAndCatch() {
+  try {
+    Throw();
+  } catch(int a) {
+    printf("ThrowAndCatch: %d\n", a);
+  }
+}
+
+void Child(int mode) {
+  char x[32] = {0};  // Stack gets poisoned.
+  printf("Child: %p\n", x);
+  ThrowAndCatch();  // Simulate __asan_handle_no_return().
+  // (a) Do nothing, just return to parent function.
+  // (b) Jump into the original function. Stack remains poisoned unless we do
+  //     something.
+  if (mode == 1) {
+    if (swapcontext(&child_context, &orig_context) < 0) {
+      perror("swapcontext");
+      _exit(0);
+    }
+  }
+}
+
+int Run(int arg, int mode, char *child_stack) {
+  printf("Child stack: %p\n", child_stack);
+  // Setup child context.
+  getcontext(&child_context);
+  child_context.uc_stack.ss_sp = child_stack;
+  child_context.uc_stack.ss_size = kStackSize / 2;
+  if (mode == 0) {
+    child_context.uc_link = &orig_context;
+  }
+  makecontext(&child_context, (void (*)())Child, 1, mode);
+  if (swapcontext(&orig_context, &child_context) < 0) {
+    perror("swapcontext");
+    return 0;
+  }
+  // Touch childs's stack to make sure it's unpoisoned.
+  for (int i = 0; i < kStackSize; i++) {
+    child_stack[i] = i;
+  }
+  return child_stack[arg];
+}
+
+int main(int argc, char **argv) {
+  char stack[kStackSize + 1];
+  // CHECK: WARNING: ASan doesn't fully support makecontext/swapcontext
+  int ret = 0;
+  ret += Run(argc - 1, 0, stack);
+  printf("Test1 passed\n");
+  // CHECK: Test1 passed
+  ret += Run(argc - 1, 1, stack);
+  printf("Test2 passed\n");
+  // CHECK: Test2 passed
+  char *heap = new char[kStackSize + 1];
+  ret += Run(argc - 1, 0, heap);
+  printf("Test3 passed\n");
+  // CHECK: Test3 passed
+  ret += Run(argc - 1, 1, heap);
+  printf("Test4 passed\n");
+  // CHECK: Test4 passed
+
+  delete [] heap;
+  return ret;
+}