Teach KLEE to respect the requested memory alignment of globals and stack

variables when possible.

Previously an alignment 8 was always used which did not faithfully
emulate what was either explicitly requested in the LLVM IR or what
the default alignment was for the target.

1 files changed, 21 insertions, 0 deletions

diff --git a/test/regression/2016-12-14-alloc-alignment.c b/test/regression/2016-12-14-alloc-alignment.c
new file mode 100644
index 00000000..db66d191
--- /dev/null
+++ b/test/regression/2016-12-14-alloc-alignment.c
@@ -0,0 +1,21 @@
+// RUN: %llvmgcc %s -Wall -emit-llvm -g -O0 -c -o %t.bc
+// RUN: rm -rf %t.klee-out
+// RUN: %klee --output-dir=%t.klee-out --exit-on-error %t.bc
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+// Global should be aligned on a 128-byte boundary
+int foo __attribute__((aligned(128)));
+
+int main() {
+  int bar __attribute__((aligned(256)));
+
+  // Check alignment of global
+  assert(((size_t)&foo) % 128 == 0);
+
+  // Check alignment of local
+  assert(((size_t)&bar) % 256 == 0);
+  return 0;
+}