Added an path-sensitive unreachable code checker to the experimental analyzer checks.

- Created a new class to do post-analysis
- Updated several test cases with unreachable code to expect a warning
- Added some general tests

llvm-svn: 109286

1 files changed, 55 insertions, 0 deletions

diff --git a/clang/test/Analysis/unreachable-code-path.c b/clang/test/Analysis/unreachable-code-path.c
new file mode 100644
index 00000000000..cfe0408c3fe
--- /dev/null
+++ b/clang/test/Analysis/unreachable-code-path.c
@@ -0,0 +1,55 @@
+// RUN: %clang_cc1 -analyze -analyzer-experimental-checks -analyzer-check-objc-mem -analyzer-check-dead-stores -verify -analyzer-opt-analyze-nested-blocks %s
+
+extern void foo(int a);
+
+void test(unsigned a) {
+  switch (a) {
+    a += 5; // expected-warning{{never executed}}
+  case 2:
+    a *= 10;
+  case 3:
+    a %= 2;
+  }
+  foo(a);
+}
+
+void test2(unsigned a) {
+ help:
+  if (a > 0)
+    return;
+  if (a == 0)
+    return;
+  foo(a); // expected-warning{{never executed}}
+  goto help;
+}
+
+void test3() {
+  int a = 5;
+
+  while (a > 1)
+    a -= 2;
+
+  if (a > 1) {
+    a = a + 56; // expected-warning{{never executed}}
+  }
+
+  foo(a);
+}
+
+void test4(unsigned a) {
+  while(1);
+  if (a > 5) { // expected-warning{{never executed}}
+    return;
+  }
+}
+
+extern void bar(char c);
+
+void test5(const char *c) {
+  foo(c[0]);
+
+  if (!c) {
+    bar(1); // expected-warning{{never executed}}
+  }
+}
+