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+/* Copyright (C) 1994 Free Software Foundation, Inc.
+   Contributed by Joel Sherrill (jsherril@redstone-emh2.army.mil),
+     On-Line Applications Research Corporation.
+ 
+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 Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+ 
+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
+Library General Public License for more details.
+ 
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/*  entry.s
+ *
+ *  This file contains the entry point for the application.
+ *  The name of this entry point is compiler dependent.
+ *  It jumps to the BSP which is responsible for performing
+ *  all initialization.
+ *
+ */
+
+         .text
+         .globl  start                  # GNU960 default entry point
+
+start:
+        mov     3, r12
+        modpc   r12, r12, r12         # enable tracing/trace faults
+        mov     g5, g5                # NOP
+        mov     0, g14                # initialize constant for C
+
+        /*
+         * zero out uninitialized data area
+         */
+zerobss:
+        lda     _end, r4        /* find end of .bss */
+        lda     _bss_start, r5  /* find beginning of .bss */
+        ldconst 0, r6
+
+loop:   st      r6, (r5)        /* to zero out uninitialized */
+        addo    4, r5, r5       /* data area                 */
+        cmpobl  r5, r4, loop    /* loop until _end reached   */
+
+
+        lda     heap_memory, r12      /* tell C lib where heap is */
+        st      r12,___C_heap_start
+        lda     heap_size, r12        /* tell C lib how big heap is */
+        st      r12,___C_heap_size
+        lda     stack_memory,r12      /* set up stack pointer: */
+        mov     r12, sp
+        mov     0, g14           /* initialize constant for C */
+
+        call    init_frames
+        ret                      /* return to monitor */
+
+init_frames:
+        ldconst 0x3b001000, g0
+        ldconst 0x00009107, g1
+        modac   g1, g0, g0       /* set AC controls */
+
+        /*
+         * Call application mainline.
+         *      Someday, real values of argc and argv will be set up.
+         *      For now, they are set to 0.
+         */
+
+        callx   __Board_Initialize    /* Initialize the board */
+
+        ldconst 0,g0
+        ldconst 0,g1
+        ldconst 0,g2
+        callx   ___libc_init          /* initialize the library and */
+                                      /*   call main */
+        /*
+         * if we return from main, we have "fallen" off the end
+         * of the program, therefore status is 0
+         * so move 0 to g0 (exit parameter)
+         */
+
+        mov     0, g0
+        callx   __exit
+        ret
+
+
+/*
+ *  Data Declarations.  Start with a macro which helps declare space.
+ */
+
+#define DECLARE_SPACE(_name,_space,_align) \
+          .globl   _name ; \
+          .align   _align ; \
+.comm     _name##,_space
+
+#define DECLARE_LABEL(_name) \
+          .globl   _name ; \
+_name##:  
+
+#define DECLARE_PTR(_name) DECLARE_SPACE(_name,4,2)
+#define DECLARE_U32(_name) DECLARE_SPACE(_name,4,2)
+#define DECLARE_U16(_name) DECLARE_SPACE(_name,2,1)
+
+/*
+ *  Require environment stuff
+ */
+
+DECLARE_LABEL(_environ)
+DECLARE_PTR(environ)
+
+DECLARE_LABEL(_errno)
+DECLARE_U32(errno)
+
+/*
+ *  Stack Size and Space
+ */
+
+        .set stack_size, 0x20000
+
+DECLARE_SPACE(stack_memory,stack_size,4)
+DECLARE_LABEL(stack_end)
+
+/*
+ *  Heap Size and Space
+ */
+
+        .set heap_size, 0x20000
+
+DECLARE_SPACE(heap_memory,heap_size,4)
+DECLARE_LABEL(heap_end)
+