1 files changed, 103 insertions, 0 deletions
diff --git a/gcc-4.9/libgcc/config/nds32/crtzero.S b/gcc-4.9/libgcc/config/nds32/crtzero.S
new file mode 100644
index 000000000..7ffd347ed
--- /dev/null
+++ b/gcc-4.9/libgcc/config/nds32/crtzero.S
@@ -0,0 +1,103 @@
+/* The startup code sample of Andes NDS32 cpu for GNU compiler
+   Copyright (C) 2012-2014 Free Software Foundation, Inc.
+   Contributed by Andes Technology Corporation.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+!!==============================================================================
+!!
+!!      crtzero.S
+!!
+!!      This is JUST A SAMPLE of nds32 startup code !!
+!!      You can refer this content and implement
+!!      the actual one in newlib/mculib.
+!!
+!!==============================================================================
+
+!!------------------------------------------------------------------------------
+!! Jump to start up code
+!!------------------------------------------------------------------------------
+	.section	.nds32_init, "ax"
+	j	_start
+
+!!------------------------------------------------------------------------------
+!! Startup code implementation
+!!------------------------------------------------------------------------------
+	.section	.text
+	.global	_start
+	.weak	_SDA_BASE_
+	.weak	_FP_BASE_
+	.align	2
+	.func	_start
+	.type	_start, @function
+_start:
+.L_fp_gp_lp_init:
+	la	$fp, _FP_BASE_		! init $fp
+	la	$gp, _SDA_BASE_		! init $gp for small data access
+	movi	$lp, 0			! init $lp
+
+.L_stack_init:
+	la	$sp, _stack		! init $sp
+	movi	$r0, -8			! align $sp to 8-byte (use 0xfffffff8)
+	and	$sp, $sp, $r0		! align $sp to 8-byte (filter out lower 3-bit)
+
+.L_bss_init:
+	! clear BSS, this process can be 4 time faster if data is 4 byte aligned
+	! if so, use swi.p instead of sbi.p
+	! the related stuff are defined in linker script
+	la	$r0, _edata		! get the starting addr of bss
+	la	$r2, _end		! get ending addr of bss
+	beq	$r0, $r2, .L_call_main	! if no bss just do nothing
+	movi	$r1, 0			! should be cleared to 0
+.L_clear_bss:
+	sbi.p	$r1, [$r0], 1		! Set 0 to bss
+	bne	$r0, $r2, .L_clear_bss	! Still bytes left to set
+
+!.L_stack_heap_check:
+!	la	$r0, _end		! init heap_end
+!	s.w	$r0, heap_end		! save it
+
+
+!.L_init_argc_argv:
+!	! argc/argv initialization if necessary; default implementation is in crt1.o
+!	la	$r9, _arg_init		! load address of _arg_init?
+!	beqz	$r9, .L4		! has _arg_init? no, go check main()
+!	addi	$sp, $sp, -512		! allocate space for command line + arguments
+!	move	$r6, $sp		! r6 = buffer addr of cmd line
+!	move	$r0, $r6		! r0 = buffer addr of cmd line
+!	syscall	6002			! get cmd line
+!	move	$r0, $r6		! r0 = buffer addr of cmd line
+!	addi	$r1, $r6, 256		! r1 = argv
+!	jral	$r9			! init argc/argv
+!	addi	$r1, $r6, 256		! r1 = argv
+
+.L_call_main:
+	! call main() if main() is provided
+	la	$r15, main		! load address of main
+	jral	$r15			! call main
+
+.L_terminate_program:
+	syscall	0x1			! use syscall 0x1 to terminate program
+	.size	_start, .-_start
+	.end
+
+!! ------------------------------------------------------------------------