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* file.
*/
#include "config.h"
#include "platform.h"
.intel_syntax noprefix
.globl objc_msg_lookup
.globl objc_msg_lookup_stret
.globl objc_msg_lookup_super
.globl objc_msg_lookup_super_stret
.section .text
.macro GENERATE_LOOKUP name notFound
\name:
movl 4(%esp), %edx
testl %edx, %edx
jz returnNilMethod
mov edx, [esp + 4]
test edx, edx
jz short returnNilMethod
testb $1, %dl
jnz .LtaggedPointer_\name
test dl, 1
jnz short .LtaggedPointer_\name
movl (%edx), %edx
movl 32(%edx), %edx
mov edx, [edx]
mov edx, [edx + 32]
.Lmain_\name:
movl 8(%esp), %eax
mov eax, [esp + 8]
#ifdef OF_SELUID24
movzbl 2(%eax), %ecx
movl (%edx,%ecx,4), %edx
movzx ecx, byte ptr [eax + 2]
mov edx, [edx + 4 * ecx]
#endif
movzbl 1(%eax), %ecx
movl (%edx,%ecx,4), %edx
movzbl (%eax), %ecx
movl (%edx,%ecx,4), %eax
movzx ecx, byte ptr [eax + 1]
mov edx, [edx + 4 * ecx]
movzx ecx, byte ptr [eax]
mov eax, [edx + 4 * ecx]
testl %eax, %eax
jz 0f
test eax, eax
jz short 0f
ret
0:
call getEIP
addl $_GLOBAL_OFFSET_TABLE_, %eax
movl \notFound@GOT(%eax), %eax
jmp *%eax
add eax, offset _GLOBAL_OFFSET_TABLE_
mov eax, [eax + \notFound@GOT]
jmp eax
.LtaggedPointer_\name:
call getEIP
addl $_GLOBAL_OFFSET_TABLE_, %eax
add eax, offset _GLOBAL_OFFSET_TABLE_
movl objc_taggedPointerSecret@GOT(%eax), %ecx
xorl (%ecx), %edx
andb $0xE, %dl
movzbl %dl, %edx
mov ecx, [eax + objc_taggedPointerSecret@GOT]
xor edx, [ecx]
and dl, 0xE
movzx edx, dl
movl objc_taggedPointerClasses@GOT(%eax), %eax
movl (%eax,%edx,2), %edx
movl 32(%edx), %edx
mov eax, [eax + objc_taggedPointerClasses@GOT]
mov edx, [eax + 2 * edx]
mov edx, [edx + 32]
jmp .Lmain_\name
jmp short .Lmain_\name
.type \name, %function
.size \name, .-\name
.endm
.macro GENERATE_LOOKUP_SUPER name lookup
\name:
movl 4(%esp), %edx
movl (%edx), %eax
testl %eax, %eax
jz returnNilMethod
mov edx, [esp + 4]
mov eax, [edx]
test eax, eax
jz short returnNilMethod
movl %eax, 4(%esp)
mov 4(%edx), %edx
mov 32(%edx), %edx
jmp .Lmain_\lookup
mov [esp + 4], eax
mov edx, [edx + 4]
mov edx, [edx + 32]
jmp short .Lmain_\lookup
.type \name, %function
.size \name, .-\name
.endm
GENERATE_LOOKUP objc_msg_lookup objc_methodNotFound
GENERATE_LOOKUP objc_msg_lookup_stret objc_methodNotFound_stret
GENERATE_LOOKUP_SUPER objc_msg_lookup_super objc_msg_lookup
GENERATE_LOOKUP_SUPER objc_msg_lookup_super_stret objc_msg_lookup_stret
returnNilMethod:
call getEIP
addl $_GLOBAL_OFFSET_TABLE_, %eax
leal nilMethod@GOTOFF(%eax), %eax
add eax, offset _GLOBAL_OFFSET_TABLE_
lea eax, [eax + nilMethod@GOTOFF]
ret
nilMethod:
xorl %eax, %eax
xor eax, eax
ret
getEIP:
movl (%esp), %eax
mov eax, [esp]
ret
#if defined(OF_LINUX) || defined(OF_HAIKU) || defined(OF_HURD)
.section .note.GNU-stack, "", %progbits
#endif
|