From ef8c264873ee6f88651699ebbbd15bc1c5065ef2 Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Fri, 26 Nov 2010 13:40:40 +0100
Subject: [PATCH] FFI: Add macros for consistent number to integer truncation.

---
 src/lj_obj.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/lj_obj.h b/src/lj_obj.h
index 83e30b6e..b417dce7 100644
--- a/src/lj_obj.h
+++ b/src/lj_obj.h
@@ -761,6 +761,13 @@ static LJ_AINLINE int32_t lj_num2bit(lua_Number n)
 #define lj_num2int(n)   ((int32_t)(n))
 #endif
 
+/* Truncate towards zero. */
+#define lj_trnum2int32(n)	((int32_t)(n))
+#define lj_trnum2uint32(n)	((uint32_t)(n))
+#define lj_trnum2int64(n)	((int64_t)(n))
+#define lj_trnum2uint64(n) \
+  ((uint64_t)(int64_t)((n)- 9223372036854775808.0) + U64x(80000000,00000000))
+
 /* -- Miscellaneous object handling --------------------------------------- */
 
 /* Names and maps for internal and external object tags. */