util: Add assume() macro.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
diff --git a/src/util/macros.h b/src/util/macros.h
index 40ebf02..ff37a7d 100644
--- a/src/util/macros.h
+++ b/src/util/macros.h
@@ -75,6 +75,20 @@
#define unreachable(str)
#endif
+/**
+ * Assume macro. Useful for expressing our assumptions to the compiler,
+ * typically for purposes of silencing warnings.
+ */
+#ifdef HAVE___BUILTIN_UNREACHABLE
+#define assume(expr) ((expr) ? ((void) 0) \
+ : (assert(!"assumption failed"), \
+ __builtin_unreachable()))
+#elif _MSC_VER >= 1200
+#define assume(expr) __assume(expr)
+#else
+#define assume(expr) assert(expr)
+#endif
+
#ifdef HAVE_FUNC_ATTRIBUTE_FLATTEN
#define FLATTEN __attribute__((__flatten__))
#else