Add position independent code for crt1.S.

This will generate a Scrt1.o that is linked to executabled
when compiled as PIE code (position independent executable) without
requiring relocation in .text section (not allowed on uclibc/sh4).

Signed-off-by: Peter Griffin <pgriffin@mpc-data.co.uk>
Signed-off-by: Filippo Arcidiacono <filippo.arcidiacono@st.com>

libc/sysdeps/linux/sh/crt1.S

@@ -56,6 +56,35 @@ _start:
 	/* Push the stack_end, rtld_fini and fini func onto the stack */
 	mov.l r6,@-r15
 	mov.l r4,@-r15
+
+#ifdef __PIC__
+	mova  L_got, r0
+	mov.l L_got, r12
+	add r0, r12
+
+	mov.l L_fini,r0
+	add r12, r0
+	mov.l r0,@-r15
+
+	/* Set up the main/init funcs that go in registers */
+	mov.l L_main, r4
+	add r12, r4
+	mov.l L_init, r7
+	add r12, r7
+
+	/* __uClibc_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
+
+	/* Let the libc call main and exit with its return code.  */
+	mov.l L_uClibc_main,r0
+	mov.l @(r0,r12),r1
+	jsr @r1
+	nop
+	/* We should not get here. */
+	mov.l L_abort,r0
+	mov.l @(r0,r12),r1
+	jsr @r1
+	nop
+#else
 	mov.l L_fini,r0
 	mov.l r0,@-r15
 
@@ -73,10 +102,25 @@ _start:
 	mov.l L_abort,r1
 	jmp @r1
 	nop
+#endif
 
 	.size _start,.-_start
 	.align	2
 
+#ifdef __PIC__
+L_got:
+	.long	_GLOBAL_OFFSET_TABLE_
+L_main:
+	.long	main@GOTOFF
+L_init:
+	.long   _init@GOTOFF
+L_fini:
+	.long   _fini@GOTOFF
+L_uClibc_main:
+	.long   __uClibc_main@GOT
+L_abort:
+	.long   abort@GOT
+#else
 L_main:
 	.long   main
 L_init:
@@ -87,6 +131,7 @@ L_uClibc_main:
 	.long   __uClibc_main
 L_abort:
 	.long   abort
+#endif
 
 /* Define a symbol for the first piece of initialized data.  */
 	.data