aboutsummaryrefslogtreecommitdiff
path: root/llimits.h
diff options
context:
space:
mode:
authorRoberto Ierusalimschy <roberto@inf.puc-rio.br>2013-05-23 18:27:06 -0300
committerRoberto Ierusalimschy <roberto@inf.puc-rio.br>2013-05-23 18:27:06 -0300
commite2c8c756eea9ecb51b05ade661ef1367e47e623c (patch)
tree1c60f1c41d6af9e1da6af6be31fa6d35ddb7a8f2 /llimits.h
parent5ca5086c191259dd88cc51161a82e93759136486 (diff)
downloadlua-e2c8c756eea9ecb51b05ade661ef1367e47e623c.tar.gz
lua-e2c8c756eea9ecb51b05ade661ef1367e47e623c.tar.bz2
lua-e2c8c756eea9ecb51b05ade661ef1367e47e623c.zip
removed 'IEEE tricks' (should not be needed in Lua with integers)
Diffstat (limited to 'llimits.h')
-rw-r--r--llimits.h57
1 files changed, 1 insertions, 56 deletions
diff --git a/llimits.h b/llimits.h
index 09355708..e15c1fd5 100644
--- a/llimits.h
+++ b/llimits.h
@@ -1,5 +1,5 @@
1/* 1/*
2** $Id: llimits.h,v 1.103 2013/02/20 14:08:56 roberto Exp roberto $ 2** $Id: llimits.h,v 1.104 2013/04/25 21:15:37 roberto Exp roberto $
3** Limits, basic types, and some other `installation-dependent' definitions 3** Limits, basic types, and some other `installation-dependent' definitions
4** See Copyright Notice in lua.h 4** See Copyright Notice in lua.h
5*/ 5*/
@@ -202,52 +202,6 @@ typedef lu_int32 Instruction;
202** both small and large values (outside the range of integers). 202** both small and large values (outside the range of integers).
203*/ 203*/
204 204
205#if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK) /* { */
206/* trick with Microsoft assembler for X86 */
207
208#define lua_number2int(i,n) __asm {__asm fld n __asm fistp i}
209#define lua_number2integer(i,n) lua_number2int(i, n)
210#define lua_number2unsigned(i,n) \
211 {__int64 l; __asm {__asm fld n __asm fistp l} i = (unsigned int)l;}
212
213
214#elif defined(LUA_IEEE754TRICK) /* }{ */
215/* the next trick should work on any machine using IEEE754 with
216 a 32-bit int type */
217
218union luai_Cast { double l_d; LUA_INT32 l_p[2]; };
219
220#if !defined(LUA_IEEEENDIAN) /* { */
221#define LUAI_EXTRAIEEE \
222 static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};
223#define LUA_IEEEENDIANLOC (ieeeendian.l_p[1] == 33)
224#else
225#define LUA_IEEEENDIANLOC LUA_IEEEENDIAN
226#define LUAI_EXTRAIEEE /* empty */
227#endif /* } */
228
229#define lua_number2int32(i,n,t) \
230 { LUAI_EXTRAIEEE \
231 volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \
232 (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; }
233
234#define luai_hashnum(i,n) \
235 { volatile union luai_Cast u; u.l_d = (n) + 1.0; /* avoid -0 */ \
236 (i) = u.l_p[0]; (i) += u.l_p[1]; } /* add double bits for his hash */
237
238#define lua_number2int(i,n) lua_number2int32(i, n, int)
239#define lua_number2unsigned(i,n) lua_number2int32(i, n, lua_Unsigned)
240
241/* the trick can be expanded to lua_Integer when it is a 32-bit value */
242#if defined(LUA_IEEELL)
243#define lua_number2integer(i,n) lua_number2int32(i, n, lua_Integer)
244#endif
245
246#endif /* } */
247
248
249/* the following definitions always work, but may be slow */
250
251#if !defined(lua_number2int) 205#if !defined(lua_number2int)
252#define lua_number2int(i,n) ((i)=(int)(n)) 206#define lua_number2int(i,n) ((i)=(int)(n))
253#endif 207#endif
@@ -269,15 +223,6 @@ union luai_Cast { double l_d; LUA_INT32 l_p[2]; };
269#endif /* } */ 223#endif /* } */
270 224
271 225
272#if !defined(lua_unsigned2number)
273/* on several machines, coercion from unsigned to double is slow,
274 so it may be worth to avoid */
275#define lua_unsigned2number(u) \
276 (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))
277#endif
278
279
280
281#if defined(ltable_c) && !defined(luai_hashnum) 226#if defined(ltable_c) && !defined(luai_hashnum)
282 227
283#include <float.h> 228#include <float.h>