llvm-project/compiler-rt/lib/builtins/x86_64/chkstk.S

41 lines
1009 B
ArmAsm

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#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__