blob: 4149ac63d9d01412e43da4cb4db5c136b9e2cb5d [file] [log] [blame]
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
#include "../assembly.h"
// _chkstk routine
// This routine is windows specific
// http://msdn.microsoft.com/en-us/library/ms648426.aspx
// Notes from r227519
// MSVC x64s __chkstk and cygmings ___chkstk_ms do not adjust %rsp
// themselves. It also does not clobber %rax so we can reuse it when
// adjusting %rsp.
#ifdef __x86_64__
.text
.balign 4
DEFINE_COMPILERRT_FUNCTION(___chkstk_ms)
push %rcx
push %rax
cmp $0x1000,%rax
lea 24(%rsp),%rcx
jb 1f
2:
sub $0x1000,%rcx
test %rcx,(%rcx)
sub $0x1000,%rax
cmp $0x1000,%rax
ja 2b
1:
sub %rax,%rcx
test %rcx,(%rcx)
pop %rax
pop %rcx
ret
END_COMPILERRT_FUNCTION(___chkstk_ms)
#endif // __x86_64__