update for HEAD-2003050101

[reactos.git] / lib / ntdll / rtl / i386 / ftol.c

diff --git a/lib/ntdll/rtl/i386/ftol.c b/lib/ntdll/rtl/i386/ftol.c
new file mode 100644 (file)
index 0000000..0832486
--- /dev/null
+++ b/lib/ntdll/rtl/i386/ftol.c
@@ -0,0 +1,35 @@
+/* $Id$
+ *
+ * COPYRIGHT:         See COPYING in the top level directory
+ * PROJECT:           ReactOS kernel
+ * PURPOSE:           Security manager
+ * FILE:              lib/ntdll/rtl/i386/ftol.c
+ * PROGRAMER:         Ge van Geldorp (ge@gse.nl)
+ * REVISION HISTORY:  2003/04/24 Created
+ */
+
+/*
+ * This routine is called by MSVC-generated code to convert from floating point
+ * to integer representation. The floating point number to be converted is
+ * on the top of the floating point stack.
+ */
+long long __cdecl _ftol(void)
+{
+  unsigned short cw_orig;
+  unsigned short cw_round_chop;
+  long long ll;
+
+  /* Set "round towards zero" mode */
+  __asm__("fstcw %0\n\t" : "=m" (cw_orig));
+  __asm__("fwait\n\t");
+  cw_round_chop = cw_orig | 0x0c00;
+  __asm__("fldcw %0\n\t" : : "m" (cw_round_chop));
+
+  /* Do the actual conversion */
+  __asm__("fistpq %0\n\t" : "=m" (ll) );
+
+  /* And restore the rounding mode */
+  __asm__("fldcw %0\n\t" : : "m" (cw_orig));
+
+  return ll;
+}