commit fd80e63468f0c08fedd8dbf944fa4954b72d7384
parent f62565abea4e56f6bd064df83e5b0f3818b99d82
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 13 Jun 2011 11:12:42 -0300
configuration for NaN trick big-endian + macro 'luai_checknum' to
ensure numbers comming from C are not "improper" (some kinds of
signaling NaNs)
Diffstat:
3 files changed, 50 insertions(+), 7 deletions(-)
diff --git a/lapi.c b/lapi.c
@@ -1,5 +1,5 @@
/*
-** $Id: lapi.c,v 2.147 2011/05/31 18:27:56 roberto Exp roberto $
+** $Id: lapi.c,v 2.148 2011/06/02 19:31:40 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
@@ -463,6 +463,8 @@ LUA_API void lua_pushnil (lua_State *L) {
LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
lua_lock(L);
setnvalue(L->top, n);
+ luai_checknum(L, L->top,
+ luaG_runerror(L, "C API - attempt to push a signaling NaN"));
api_incr_top(L);
lua_unlock(L);
}
diff --git a/lobject.h b/lobject.h
@@ -1,5 +1,5 @@
/*
-** $Id: lobject.h,v 2.58 2011/06/07 19:02:33 roberto Exp roberto $
+** $Id: lobject.h,v 2.59 2011/06/09 18:21:25 roberto Exp roberto $
** Type definitions for Lua objects
** See Copyright Notice in lua.h
*/
@@ -262,7 +262,7 @@ typedef struct lua_TValue TValue;
** =======================================================
*/
-#if defined(LUA_NANTRICK)
+#if defined(LUA_NANTRICKLE) || defined(LUA_NANTRICKBE)
/*
** numbers are represented in the 'd_' field. All other values have the
@@ -270,11 +270,20 @@ typedef struct lua_TValue TValue;
** a "signaled NaN", which is never generated by regular operations by
** the CPU (nor by 'strtod')
*/
+#if !defined(NNMARK)
#define NNMARK 0x7FF7A500
+#endif
#undef TValuefields
+#if defined(LUA_NANTRICKLE)
+/* little endian */
#define TValuefields \
union { struct { Value v_; int tt_; } i; double d_; } u
+#else
+/* big endian */
+#define TValuefields \
+ union { struct { int tt_; Value v_; } i; double d_; } u
+#endif
#undef numfield
#define numfield /* no such field; numbers are the entire struct */
@@ -322,6 +331,14 @@ typedef struct lua_TValue TValue;
(ttisnumber(o1) ? ttisnumber(o2) : ((o1)->u.i.tt_ == (o2)->u.i.tt_))
+
+#define luai_checknum(L,o,c) { if (!ttisnumber(o)) c; }
+
+
+#else
+
+#define luai_checknum(L,o,c) { /* empty */ }
+
#endif
/* }====================================================== */
diff --git a/luaconf.h b/luaconf.h
@@ -1,5 +1,5 @@
/*
-** $Id: luaconf.h,v 1.157 2011/04/29 13:56:28 roberto Exp roberto $
+** $Id: luaconf.h,v 1.158 2011/05/26 16:09:40 roberto Exp roberto $
** Configuration file for Lua
** See Copyright Notice in lua.h
*/
@@ -465,11 +465,11 @@
/*
@@ LUA_IEEEENDIAN is the endianness of doubles in your machine
-@@ (0 for little endian, 1 for big endian); if not defined, Lua will
-@@ check it dynamically.
+** (0 for little endian, 1 for big endian); if not defined, Lua will
+** check it dynamically.
*/
/* check for known architectures */
-#if defined(__i386__) || defined(__i386) || defined(i386) || \
+#if defined(__i386__) || defined(__i386) || defined(__X86__) || \
defined (__x86_64)
#define LUA_IEEEENDIAN 0
#elif defined(__POWERPC__) || defined(__ppc__)
@@ -485,6 +485,30 @@
/* }================================================================== */
+/*
+@@ LUA_NANTRICKLE/LUA_NANTRICKBE controls the use of a trick to pack all
+** types into a single double value, using NaN values to represent
+** non-number values. The trick only works on 32-bit machines (ints and
+** pointers are 32-bit values) with numbers represented as IEEE 754-2008
+** doubles with conventional endianess (12345678 or 87654321), in CPUs
+** that do not produce signaling NaN values (all NaNs are quiet).
+*/
+#if defined(LUA_CORE) /* { */
+
+#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI) /* { */
+
+/* little-endian architectures that satisfy those conditions */
+#if defined(__i386__) || defined(__i386) || defined(__X86__)
+
+#define LUA_NANTRICKLE
+
+#endif
+
+#endif /* } */
+
+#endif /* } */
+
+
/* =================================================================== */
