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/* ---------------------------------------------- */
/* alloca.S */
#ifdef __leading_underscore
# define _(s) _##s
#else
# define _(s) s
#endif
/* ---------------------------------------------- */
#if defined __i386__
.globl _(alloca), _(__alloca)
_(alloca):
_(__alloca):
push %ebp
mov %esp,%ebp
mov 8(%ebp),%eax
add $3,%eax
and $-4,%eax
#ifdef _WIN32
jmp .+16 #p2
p1:
sub $4096,%esp
sub $4096,%eax
test %eax,(%esp)
p2:
cmp $4096,%eax
jae p1
#endif
sub %eax,%esp
mov 4(%ebp),%eax
mov 0(%ebp),%ebp
add $8,%esp
push %eax
lea 8(%esp),%eax
ret
/* ---------------------------------------------- */
#elif defined __x86_64__
.globl _(alloca)
_(alloca):
pop %rdx
#ifdef _WIN32
mov %rcx,%rax
#else
mov %rdi,%rax
#endif
add $15,%rax
and $-16,%rax
jz p3
#ifdef _WIN32
p1:
cmp $4096,%rax
jbe p2
test %rax,-4096(%rsp)
sub $4096,%rsp
sub $4096,%rax
jmp p1
p2:
#endif
sub %rax,%rsp
mov %rsp,%rax
p3:
push %rdx
ret
/* ---------------------------------------------- */
#elif defined __arm__
.text
.align 2
.global alloca
.type alloca, %function
alloca:
rsb sp, r0, sp
bic sp, sp, #7
mov r0, sp
mov pc, lr
.size alloca, .-alloca
/* ---------------------------------------------- */
#endif
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