ObjFW  Check-in [0b417fb86f]

Overview
Comment:Make use of @PLT in x86/ELF ASM
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SHA3-256: 0b417fb86f16499e6ee5c0db2a757a8085c07bb42edd570809e6e1f60eafc35e
User & Date: js on 2020-06-30 00:11:12
Other Links: manifest | tags
Context
2020-06-30
00:37
Minor cleanup of x86/ELF ASM check-in: b194a9a226 user: js tags: trunk
00:11
Make use of @PLT in x86/ELF ASM check-in: 0b417fb86f user: js tags: trunk
2020-06-29
23:14
Convert all x86/ELF ASM files to Intel syntax check-in: 2073a345ba user: js tags: trunk
Changes

Modified src/forwarding/forwarding-x86-elf.S from [2e098aafbd] to [1b2ac8ff28].

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	call	get_eip
0:
	add	ebx, offset _GLOBAL_OFFSET_TABLE_

	mov	eax, [ebp+8]
	mov	[esp], eax
	mov	eax, [ebx+object_getClass@GOT]
	call	object_getClass@PLT
	call	eax

	mov	[esp], eax
	lea	eax, [ebx+sel_forwardingTargetForSelector_@GOTOFF]
	mov	[esp+4], eax
	mov	eax, [ebx+class_respondsToSelector@GOT]
	call	class_respondsToSelector@PLT
	call	eax

	test	eax, eax
	jz	short 1f

	mov	eax, [ebp+8]
	mov	[esp], eax
	lea	eax, [ebx+sel_forwardingTargetForSelector_@GOTOFF]
	mov	[esp+4], eax
	mov	eax, [ebx+objc_msg_lookup@GOT]
	call	objc_msg_lookup@PLT
	call	eax

	mov	edx, [ebp+8]
	mov	[esp], edx
	lea	edx, [ebx+sel_forwardingTargetForSelector_@GOTOFF]
	mov	[esp+4], edx
	mov	edx, [ebp+12]
	mov	[esp+8], edx
	call	eax

	test	eax, eax
	jz	short 1f
	cmp	eax, [ebp+8]
	je	short 1f

	mov	[ebp+8], eax
	mov	[esp], eax
	mov	eax, [ebp+12]
	mov	[esp+4], eax
	mov	eax, [ebx+objc_msg_lookup@GOT]
	call	objc_msg_lookup@PLT
	call	eax

	add	esp, 20
	pop	ebx
	pop	ebp

	jmp	eax

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	push	ebp
	mov	ebp, esp

	push	ebx
	sub	esp, 20

	call	get_eip
0:
	add	ebx, offset _GLOBAL_OFFSET_TABLE_

	mov	eax, [ebp+12]
	mov	[esp], eax
	mov	eax, [ebx+object_getClass@GOT]
	call	object_getClass@PLT
	call	eax

	mov	[esp], eax
	lea	eax, [ebx+sel_forwardingTargetForSelector_@GOTOFF]
	mov	[esp+4], eax
	mov	eax, [ebx+class_respondsToSelector@GOT]
	call	class_respondsToSelector@PLT
	call	eax

	test	eax, eax
	jz	short 1f

	mov	eax, [ebp+12]
	mov	[esp], eax
	lea	eax, [ebx+sel_forwardingTargetForSelector_@GOTOFF]
	mov	[esp+4], eax
	mov	eax, [ebx+objc_msg_lookup@GOT]
	call	objc_msg_lookup@PLT
	call	eax

	mov	edx, [ebp+12]
	mov	[esp], edx
	lea	edx, [ebx+sel_forwardingTargetForSelector_@GOTOFF]
	mov	[esp+4], edx
	mov	edx, [ebp+16]
	mov	[esp+8], edx
	call	eax

	test	eax, eax
	jz	short 1f
	cmp	eax, [ebp+12]
	je	short 1f

	mov	[ebp+12], eax
	mov	[esp], eax
	mov	eax, [ebp+16]
	mov	[esp+4], eax
	mov	eax, [ebx+objc_msg_lookup_stret@GOT]
	call	objc_msg_lookup_stret@PLT
	call	eax

	add	esp, 20
	pop	ebx
	pop	ebp

	jmp	eax

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	push	ebp
	mov	ebp, esp

	push	ebx
	sub	esp, 4

	call	get_eip
0:
	add	ebx, offset _GLOBAL_OFFSET_TABLE_

	lea	eax, [ebx+module@GOTOFF]
	mov	[esp], eax
	mov	eax, [ebx+__objc_exec_class@GOT]
	call	__objc_exec_class@PLT
	call	eax

	add	esp, 4
	pop	ebx
	pop	ebp
	ret

get_eip:

Modified src/runtime/lookup-asm/lookup-asm-x86-elf.S from [65ed1dc5ee] to [1aba078652].

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	test	eax, eax
	jz	short 0f

	ret

0:
	call	get_eip
1:
	add	eax, offset _GLOBAL_OFFSET_TABLE_
	mov	eax, [eax+\not_found@GOT]
	jmp	eax
.type \name, %function
.size \name, .-\name
.endm

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generate_lookup objc_msg_lookup objc_method_not_found
generate_lookup objc_msg_lookup_stret objc_method_not_found_stret
generate_lookup_super objc_msg_lookup_super objc_msg_lookup
generate_lookup_super objc_msg_lookup_super_stret objc_msg_lookup_stret

ret_nil:
	call	get_eip
0:
	add	eax, nil_method-0b
	add	eax, offset _GLOBAL_OFFSET_TABLE_
	mov	eax, [eax+nil_method@GOT]
	ret

nil_method:
	xor	eax, eax
	ret

get_eip:
	mov	eax, [esp]
	ret

#ifdef OF_LINUX
.section .note.GNU-stack, "", %progbits
#endif