cosmopolitan/third_party/compiler_rt/nexgen32e/chkstk.S
Justine Tunney e75ffde09e Get codebase completely working with LLVM
You can now build Cosmopolitan with Clang:

    make -j8 MODE=llvm
    o/llvm/examples/hello.com

The assembler and linker code is now friendly to LLVM too.
So it's not needed to configure Clang to use binutils under
the hood. If you love LLVM then you can now use pure LLVM.
2021-02-09 02:57:32 -08:00

43 lines
1 KiB
ArmAsm

// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
#include "third_party/compiler_rt/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__
.section .yoink
nopl huge_compiler_rt_license(%rip)
.previous
.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__