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      1 /* crt0-efi-x86_64.S - x86_64 EFI startup code.
      2    Copyright (C) 1999 Hewlett-Packard Co.
      3 	Contributed by David Mosberger <davidm (at) hpl.hp.com>.
      4    Copyright (C) 2005 Intel Co.
      5 	Contributed by Fenghua Yu <fenghua.yu (at) intel.com>.
      6 
      7     All rights reserved.
      8 
      9     Redistribution and use in source and binary forms, with or without
     10     modification, are permitted provided that the following conditions
     11     are met:
     12 
     13     * Redistributions of source code must retain the above copyright
     14       notice, this list of conditions and the following disclaimer.
     15     * Redistributions in binary form must reproduce the above
     16       copyright notice, this list of conditions and the following
     17       disclaimer in the documentation and/or other materials
     18       provided with the distribution.
     19     * Neither the name of Hewlett-Packard Co. nor the names of its
     20       contributors may be used to endorse or promote products derived
     21       from this software without specific prior written permission.
     22 
     23     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
     24     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
     25     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     26     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     27     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
     28     BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
     29     OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     30     PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     31     PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     32     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
     33     TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
     34     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     35     SUCH DAMAGE.
     36 */
     37 	.text
     38 	.align 4
     39 
     40 	.globl _start
     41 _start:
     42 	subq $8, %rsp
     43 	pushq %rcx
     44 	pushq %rdx
     45 
     46 0:
     47 	lea ImageBase(%rip), %rdi
     48 	lea _DYNAMIC(%rip), %rsi
     49 
     50 	popq %rcx
     51 	popq %rdx
     52 	pushq %rcx
     53 	pushq %rdx
     54 	call _relocate
     55 
     56 	popq %rdi
     57 	popq %rsi
     58 
     59 	call efi_main
     60 	addq $8, %rsp
     61 
     62 .exit:
     63   	ret
     64 
     65  	// hand-craft a dummy .reloc section so EFI knows it's a relocatable executable:
     66 
     67  	.data
     68 dummy:	.long	0
     69 
     70 #define IMAGE_REL_ABSOLUTE	0
     71  	.section .reloc, "a"
     72 label1:
     73 	.long	dummy-label1				// Page RVA
     74  	.long	10					// Block Size (2*4+2)
     75 	.word	(IMAGE_REL_ABSOLUTE<<12) +  0		// reloc for dummy
     76 
     77