[ros-diffs] [turner] 19931: Actually provide __aulldiv code.

Actually provide __aulldiv code.
Added: trunk/reactos/lib/rtl/i386/aulldiv_asm.s
Modified: trunk/reactos/lib/rtl/rtl.xml
  _____  

Added: trunk/reactos/lib/rtl/i386/aulldiv_asm.s
--- trunk/reactos/lib/rtl/i386/aulldiv_asm.s	2005-12-06 14:38:20 UTC
(rev 19930)
+++ trunk/reactos/lib/rtl/i386/aulldiv_asm.s	2005-12-06 16:41:53 UTC
(rev 19931)
@@ -0,0 +1,180 @@

+/*
+ * COPYRIGHT:         See COPYING in the top level directory
+ * PROJECT:           ReactOS kernel
+ * PURPOSE:           Run-Time Library
+ * FILE:              lib/rtl/i386/aulldiv_asm.S
+ * PROGRAMER:         Alex Ionescu (alex(a)relsoft.net)
+ *                    Eric Kohl (ekohl(a)rz-online.de)
+ *
+ * Copyright (C) 2002 Michael Ringgaard.
+ * All rights reserved. 
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer.  
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
the
+ *    documentation and/or other materials provided with the
distribution.  
+ * 3. Neither the name of the project nor the names of its contributors
+ *    may be used to endorse or promote products derived from this
software
+ *    without specific prior written permission. 
+
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS
+ * OR SERVICES// LOSS OF USE, DATA, OR PROFITS// OR BUSINESS
INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
OF 
+ * SUCH DAMAGE.
+ */
+ 
+ .globl __aulldiv
+
+.intel_syntax noprefix
+
+/* FUNCTIONS
***************************************************************/
+
+//
+// ulldiv - unsigned long divide
+//
+// Purpose:
+//       Does a unsigned long divide of the arguments.  Arguments are
+//       not changed.
+//
+// Entry:
+//       Arguments are passed on the stack:
+//               1st pushed: divisor (QWORD)
+//               2nd pushed: dividend (QWORD)
+//
+// Exit:
+//       EDX:EAX contains the quotient (dividend/divisor)
+//       NOTE: this routine removes the parameters from the stack.
+//
+// Uses:
+//       ECX
+//
+
+__aulldiv:
+
+        push    ebx
+        push    esi
+
+// Set up the local stack and save the index registers.  When this is
done
+// the stack frame will look as follows (assuming that the expression
a/b will
+// generate a call to uldiv(a, b)):
+//
+//               -----------------
+//               |               |
+//               |---------------|
+//               |               |
+//               |--divisor (b)--|
+//               |               |
+//               |---------------|
+//               |               |
+//               |--dividend (a)-|
+//               |               |
+//               |---------------|
+//               | return addr** |
+//               |---------------|
+//               |      EBX      |
+//               |---------------|
+//       ESP---->|      ESI      |
+//               -----------------
+//
+
+#undef DVNDLO
+#undef DVNDHI
+#undef DVSRLO
+#undef DVSRHI
+#define DVNDLO  [esp + 12]       // stack address of dividend (a)
+#define DVNDHI  [esp + 16]       // stack address of dividend (a)
+#define DVSRLO  [esp + 20]      // stack address of divisor (b)
+#define DVSRHI  [esp + 24]      // stack address of divisor (b)
+
+//
+// Now do the divide.  First look to see if the divisor is less than
4194304K.
+// If so, then we can use a simple algorithm with word divides,
otherwise
+// things get a little more complex.
+//
+
+        mov     eax,DVSRHI // check to see if divisor < 4194304K
+        or      eax,eax
+        jnz     short ..L1        // nope, gotta do this the hard way
+        mov     ecx,DVSRLO // load divisor
+        mov     eax,DVNDHI // load high word of dividend
+        xor     edx,edx
+        div     ecx             // get high order bits of quotient
+        mov     ebx,eax         // save high bits of quotient
+        mov     eax,DVNDLO // edx:eax <- remainder:lo word of dividend
+        div     ecx             // get low order bits of quotient
+        mov     edx,ebx         // edx:eax <- quotient hi:quotient lo
+        jmp     short ..L2        // restore stack and return
+
+//
+// Here we do it the hard way.  Remember, eax contains DVSRHI
+//
+
+..L1:
+        mov     ecx,eax         // ecx:ebx <- divisor
+        mov     ebx,DVSRLO
+        mov     edx,DVNDHI // edx:eax <- dividend
+        mov     eax,DVNDLO
+..L3:
+        shr     ecx,1           // shift divisor right one bit// hi bit
<- 0
+        rcr     ebx,1
+        shr     edx,1           // shift dividend right one bit// hi
bit <- 0
+        rcr     eax,1
+        or      ecx,ecx
+        jnz     short ..L3        // loop until divisor < 4194304K
+        div     ebx             // now divide, ignore remainder
+        mov     esi,eax         // save quotient
+
+//
+// We may be off by one, so to check, we will multiply the quotient
+// by the divisor and check the result against the orignal dividend
+// Note that we must also check for overflow, which can occur if the
+// dividend is close to 2**64 and the quotient is off by 1.
+//
+
+        mul     dword ptr DVSRHI // QUOT * DVSRHI
+        mov     ecx,eax
+        mov     eax,DVSRLO
+        mul     esi             // QUOT * DVSRLO
+        add     edx,ecx         // EDX:EAX = QUOT * DVSR
+        jc      short ..L4        // carry means Quotient is off by 1
+
+//
+// do long compare here between original dividend and the result of the
+// multiply in edx:eax.  If original is larger or equal, we are ok,
otherwise
+// subtract one (1) from the quotient.
+//
+
+        cmp     edx,DVNDHI // compare hi words of result and original
+        ja      short ..L4        // if result > original, do subtract
+        jb      short ..L5        // if result < original, we are ok
+        cmp     eax,DVNDLO // hi words are equal, compare lo words
+        jbe     short ..L5        // if less or equal we are ok, else
subtract
+..L4:
+        dec     esi             // subtract 1 from quotient
+..L5:
+        xor     edx,edx         // edx:eax <- quotient
+        mov     eax,esi
+
+//
+// Just the cleanup left to do.  edx:eax contains the quotient.
+// Restore the saved registers and return.
+//
+
+..L2:
+
+        pop     esi
+        pop     ebx
+
+        ret     16
  _____  

Modified: trunk/reactos/lib/rtl/rtl.xml
--- trunk/reactos/lib/rtl/rtl.xml	2005-12-06 14:38:20 UTC (rev
19930)
+++ trunk/reactos/lib/rtl/rtl.xml	2005-12-06 16:41:53 UTC (rev
19931)
@@ -15,6 +15,7 @@

 			<file>allshl_asm.s</file>
 			<file>allshr_asm.s</file>
 			<file>atan_asm.s</file>
+			<file>aulldiv_asm.s</file>
 			<file>aulldvrm_asm.s</file>
 			<file>aullrem_asm.s</file>
 			<file>aullshr_asm.s</file>