xref: /openbsd-src/gnu/llvm/compiler-rt/lib/builtins/i386/chkstk.S (revision 3cab2bb3f667058bece8e38b12449a63a9d73c4b)
1*3cab2bb3Spatrick// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
2*3cab2bb3Spatrick// See https://llvm.org/LICENSE.txt for license information.
3*3cab2bb3Spatrick// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
4*3cab2bb3Spatrick
5*3cab2bb3Spatrick#include "../assembly.h"
6*3cab2bb3Spatrick
7*3cab2bb3Spatrick// _chkstk routine
8*3cab2bb3Spatrick// This routine is windows specific
9*3cab2bb3Spatrick// http://msdn.microsoft.com/en-us/library/ms648426.aspx
10*3cab2bb3Spatrick
11*3cab2bb3Spatrick#ifdef __i386__
12*3cab2bb3Spatrick
13*3cab2bb3Spatrick.text
14*3cab2bb3Spatrick.balign 4
15*3cab2bb3SpatrickDEFINE_COMPILERRT_FUNCTION(__chkstk_ms)
16*3cab2bb3Spatrick        push   %ecx
17*3cab2bb3Spatrick        push   %eax
18*3cab2bb3Spatrick        cmp    $0x1000,%eax
19*3cab2bb3Spatrick        lea    12(%esp),%ecx
20*3cab2bb3Spatrick        jb     1f
21*3cab2bb3Spatrick2:
22*3cab2bb3Spatrick        sub    $0x1000,%ecx
23*3cab2bb3Spatrick        test   %ecx,(%ecx)
24*3cab2bb3Spatrick        sub    $0x1000,%eax
25*3cab2bb3Spatrick        cmp    $0x1000,%eax
26*3cab2bb3Spatrick        ja     2b
27*3cab2bb3Spatrick1:
28*3cab2bb3Spatrick        sub    %eax,%ecx
29*3cab2bb3Spatrick        test   %ecx,(%ecx)
30*3cab2bb3Spatrick        pop    %eax
31*3cab2bb3Spatrick        pop    %ecx
32*3cab2bb3Spatrick        ret
33*3cab2bb3SpatrickEND_COMPILERRT_FUNCTION(__chkstk_ms)
34*3cab2bb3Spatrick
35*3cab2bb3Spatrick#endif // __i386__
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