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authorAndreas Jaeger <aj@suse.de>2012-03-23 17:37:31 +0100
committerAndreas Jaeger <jaegerandi@gmail.com>2012-03-28 09:31:13 +0200
commitbbaf00a652cad1057d5a96b79172b02d942c6961 (patch)
tree2bfc6c38f81e28efc2b78ed285944aab0b9e429c /sysdeps/s390/s390-32/start.S
parent39197fb03fd7fbef8a4ddff6cd93b5b5eb9e24d9 (diff)
downloadglibc-bbaf00a652cad1057d5a96b79172b02d942c6961.tar.gz
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Move sysdeps/s390/s390-32/elf files
	* sysdeps/s390/s390-32/elf/bsd-_setjmp.S: Moved to ...
	* sysdeps/s390/s390-32/bsd-_setjmp.S: ... here.
	* sysdeps/s390/s390-32/elf/bsd-setjmp.S: Moved to ...
	* sysdeps/s390/s390-32/bsd-setjmp.S: ... here.
	* sysdeps/s390/s390-32/elf/setjmp.S: Moved to ...
	* sysdeps/s390/s390-32/setjmp.S: ... here.
	* sysdeps/s390/s390-32/elf/configure.in: Moved to ...
	* sysdeps/s390/s390-32/configure.in: ... here.
	* sysdeps/s390/s390-32/elf/configure: Delete file.
	* sysdeps/s390/s390-32/elf/start.S: Moved to ...
	* sysdeps/s390/s390-32/start.S: ... here.
Diffstat (limited to 'sysdeps/s390/s390-32/start.S')
-rw-r--r--sysdeps/s390/s390-32/start.S212
1 files changed, 212 insertions, 0 deletions
diff --git a/sysdeps/s390/s390-32/start.S b/sysdeps/s390/s390-32/start.S
new file mode 100644
index 0000000000..d7f3df7f66
--- /dev/null
+++ b/sysdeps/s390/s390-32/start.S
@@ -0,0 +1,212 @@
+/* Startup code compliant to the ELF s390 ABI.
+   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2006
+   Free Software Foundation, Inc.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file with other
+   programs, and to distribute those programs without any restriction
+   coming from the use of this file. (The GNU Lesser General Public
+   License restrictions do apply in other respects; for example, they
+   cover modification of the file, and distribution when not linked
+   into another program.)
+
+   Note that people who make modified versions of this file are not
+   obligated to grant this special exception for their modified
+   versions; it is their choice whether to do so. The GNU Lesser
+   General Public License gives permission to release a modified
+   version without this exception; this exception also makes it
+   possible to release a modified version which carries forward this
+   exception.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/*
+   This is the canonical entry point, usually the first thing in the text
+   segment. Most registers' values are unspecified, except for:
+
+   %r14         Contains a function pointer to be registered with `atexit'.
+		This is how the dynamic linker arranges to have DT_FINI
+		functions called for shared libraries that have been loaded
+		before this code runs.
+
+   %r15		The stack contains the arguments and environment:
+		0(%r15)			argc
+		4(%r15)			argv[0]
+		...
+		(4*argc)(%r15)		NULL
+		(4*(argc+1))(%r15)	envp[0]
+		...
+					NULL
+*/
+
+	.text
+	.globl _start
+	.type _start,@function
+_start:
+	/* Check if the kernel provides highgprs facility if needed by
+	   the binary.  */
+
+	lr	%r6,%r15
+	la	%r6,4(%r6)     /* Skip the argument counter.  */
+
+.L11:	l	%r5,0(%r6)     /* Skip the argument vector.  */
+	la	%r6,4(%r6)
+	ltr	%r5,%r5
+	jne	.L11
+
+.L12:	l	%r5,0(%r6)     /* Skip the environment vector.  */
+	la	%r6,4(%r6)
+	ltr	%r5,%r5
+	jne	.L12
+
+	/* Usually the auxiliary vector can be expected directly after
+	   the environment variables.  But we have to skip extra zeros
+	   because the loader might have removed unsecure variables for
+	   setuid programs.  */
+
+.L26:	l	%r5,0(%r6)
+	la	%r6,4(%r6)
+	ltr	%r5,%r5
+	jz	.L26
+
+	ahi	%r6,-4
+
+	/* Obtain the needed values from the auxiliary vector.  */
+
+	lhi	%r7,16	       /* AT_HWCAP */
+	lhi	%r8,3	       /* AT_PHDR */
+	lhi	%r9,5          /* AT_PHNUM */
+	lhi	%r2,4          /* AT_PHENT */
+.L13:	l	%r5,0(%r6)
+	clr	%r5,%r7
+	jne	.L15
+	l	%r10,4(%r6)    /* r10 = AT_HWCAP value.  */
+.L15:	clr	%r5,%r8
+	jne	.L16
+	l	%r11,4(%r6)    /* r11 = AT_PHDR value.  */
+.L16:	clr	%r5,%r9
+	jne	.L17
+	l	%r12,4(%r6)    /* r12 = AT_PHNUM value.  */
+.L17:	clr	%r5,%r2
+	jne	.L18
+	l	%r0,4(%r6)     /* r0 = AT_PHENT value.  */
+.L18:	ltr	%r5,%r5
+	la	%r6,8(%r6)
+	jnz	.L13
+
+	/* Locate the ELF header by looking for the first PT_LOAD
+	   segment with a p_offset of zero.  */
+
+	lr	%r4,%r11       /* Backup AT_PHDR.  */
+	lhi	%r7,1          /* PT_LOAD id */
+	lhi	%r8,0
+.L19:	cl	%r7,0(%r4)     /* p_type == PT_LOAD? */
+	jne	.L20
+	cl	%r8,4(%r4)     /* p_offset == 0? */
+	jne	.L20
+	l	%r9,8(%r4)     /* r9 = PT_LOAD.p_vaddr <- ELF header address  */
+	j	.L24
+.L20:	alr	%r4,%r0        /* r4 += AT_PHENT value */
+	brct	%r12,.L19
+
+	j	.+2            /* Trap, there must be such a phdr.  */
+
+.L24:	lr	%r4,%r11       /* Backup AT_PHDR.  */
+	lhi	%r2,6          /* PT_PHDR id */
+.L23:	cl	%r2,0(%r4)
+	jne	.L22
+	l	%r3,8(%r4)     /* r3 = PT_PHDR p_vaddr */
+	j	.L25
+.L22:	alr	%r4,%r0        /* r4 += AT_PHENT value */
+	brct	%r12,.L23
+
+	j	.L14	       /* No PT_PHDR found - skip checking.  */
+
+.L25:	slr	%r11,%r3       /* AT_PHDR - PT_PHDR.p_vaddr (relocation offset)*/
+	alr	%r9,%r11       /* PT_LOAD.p_vaddr += relocation offset */
+
+	l	%r5,36(%r9)    /* Load the e_flags field.  */
+	tml	%r5,1
+	jz	.L14	       /* Binary does not require highgprs facility.  */
+
+	tml	%r10,512       /* Check the AT_HWCAP value.  */
+	jz	2              /* Trap if no highgprs facility available.  */
+.L14:
+
+	/* Setup pointer to literal pool of _start */
+	basr    %r13,0
+.L0:    ahi     %r13,.Llit-.L0
+
+	/* load argc and argv from stack */
+	la      %r4,4(%r15)             # get argv
+	l       %r3,0(%r15)             # get argc
+
+	/* align the stack to a double word boundary */
+	lhi     %r0,-8
+	nr      %r15,%r0
+
+	/* Setup a stack frame and a parameter area */
+	ahi     %r15,-104               # make room on stack
+	xc      0(4,%r15),0(%r15)       # clear back-chain
+
+	/* set up arguments for __libc_start_main:
+	   main, argc, argv, envp, _init, _fini, rtld_fini, stack_end
+	   Note that envp will be determined later in __libc_start_main
+	 */
+	stm     %r14,%r15,96(%r15)      # store rtld_fini/stack_end to parameter area
+	la      %r7,96(%r15)
+	l       %r6,.L2-.Llit(%r13)     # load pointer to __libc_csu_fini
+	l       %r5,.L1-.Llit(%r13)     # load pointer to __libc_csu_init
+	l       %r2,.L3-.Llit(%r13)     # load pointer to main
+	l       %r1,.L4-.Llit(%r13)	# load pointer to __libc_start_main
+#ifdef PIC
+	l       %r12,.L5-.Llit(%r13)    # load .got pointer
+	la	%r6,0(%r13,%r6)
+	la	%r5,0(%r13,%r5)
+	la	%r12,0(%r13,%r12)
+	l	%r2,0(%r12,%r2)
+	la	%r1,0(%r13,%r1)
+#endif
+
+	/* ok, now branch to the libc main routine */
+	basr    %r14,%r1
+
+	/* crash if __libc_start_main returns */
+	.word   0
+
+.Llit:
+#ifndef PIC
+.L1:    .long  __libc_csu_init
+.L2:    .long  __libc_csu_fini
+.L3:    .long  main
+.L4:    .long  __libc_start_main
+#else
+.L1:    .long  __libc_csu_init-.Llit
+.L2:    .long  __libc_csu_fini-.Llit
+.L3:    .long  main@GOT
+.L4:    .long  __libc_start_main@plt-.Llit
+.L5:    .long  _GLOBAL_OFFSET_TABLE_-.Llit
+#endif
+
+/* Define a symbol for the first piece of initialized data.  */
+	.data
+	.globl __data_start
+__data_start:
+	.long 0
+	.weak data_start
+	data_start = __data_start