tinycc/lib/alloca86_64-bt.S

61 lines
1.1 KiB
ArmAsm

/* ---------------------------------------------- */
/* alloca86_64.S */
.globl __bound_alloca
__bound_alloca:
#ifdef TCC_TARGET_PE
# bound checking is not implemented
pop %rdx
mov %rcx,%rax
add $15,%rax
and $-16,%rax
jz p3
p1:
cmp $4096,%rax
jbe p2
test %rax,-4096(%rsp)
sub $4096,%rsp
sub $4096,%rax
jmp p1
p2:
sub %rax,%rsp
mov %rsp,%rax
add $32,%rax
p3:
push %rdx
ret
#else
pop %rdx
mov %rdi,%rax
movl %rax,%rsi # size, a second parm to the __bound_new_region
add $15,%rax
and $-16,%rax
jz p3
sub %rax,%rsp
mov %rsp,%rdi # pointer, a first parm to the __bound_new_region
mov %rsp,%rax
push %rdx
push %rax
call __bound_new_region
pop %rax
pop %rdx
p3:
push %rdx
ret
#endif
/* mark stack as nonexecutable */
#if defined __ELF__ && defined __linux__
.section .note.GNU-stack,"",@progbits
#endif
/* ---------------------------------------------- */