20000317 sourceware import

1 files changed, 128 insertions, 0 deletions

diff --git a/libgloss/pa/crt0.S b/libgloss/pa/crt0.S
new file mode 100644
index 000000000..e9ea525a8
--- /dev/null
+++ b/libgloss/pa/crt0.S
@@ -0,0 +1,128 @@
+/* crt0.S -- startup file for hppa.
+ *
+ * Copyright (c) 1995 Cygnus Support
+ *
+ * The authors hereby grant permission to use, copy, modify, distribute,
+ * and license this software and its documentation for any purpose, provided
+ * that existing copyright notices are retained in all copies and that this
+ * notice is included verbatim in any distributions. No written agreement,
+ * license, or royalty fee is required for any of the authorized uses.
+ * Modifications to this software may be copyrighted by their authors
+ * and need not follow the licensing terms described here, provided that
+ * the new terms are clearly indicated on the first page of each file where
+ * they apply.
+ */
+	.VERSION "1.0"
+	.COPYRIGHT "crt0.o for the PA"
+
+	.DATA
+
+/* 
+ * Set up the standard spaces (sections) These definitions come
+ * from /lib/pcc_prefix.s.
+ */
+	.TEXT
+	
+/*
+ * stuff we need that's defined elsewhere.
+ */
+	.IMPORT main, CODE
+	.IMPORT exit, CODE
+	.IMPORT _bss_start, DATA
+	.IMPORT _end, DATA
+	.IMPORT environ, DATA
+
+/*
+ * start -- set things up so the application will run.
+ *
+ */
+        .PROC
+        .CALLINFO SAVE_SP, FRAME=48
+        .EXPORT $START$,ENTRY
+$START$
+
+	/* FIXME: this writes to page zero */
+	;; setup the %30 (stack pointer) with some memory
+	ldil 	L%_stack,%r30
+        ldo 	R%_stack(%r30),%r30
+
+	;; we need to set %r27 (global data pointer) here too 
+	ldil 	L%$global$,%r27
+        ldo 	R%$global$(%r27),%r27		; same problem as above
+
+/*
+ * zerobss -- zero out the bss section
+ */
+	; load the start of bss
+	ldil 	L%_bss_start,%r4
+        ldo 	R%_bss_start(%r4),%r4
+
+	;  load the end of bss
+	ldil 	L%_end,%r5
+        ldo 	R%_end(%r5),%r5
+
+
+L$bssloop
+	addi	-1,%r5,%r5			; decrement _bss_end
+	stb	%r0,0(0,%r5)			; we do this by bytes for now even
+						; though it's slower, it's safer
+	combf,=	%r4,%r5, L$bssloop	
+	nop
+	
+	ldi	1,%ret0
+
+/*
+ * Call the main routine from the application to get it going.
+ * main (argc, argv, environ)
+ * We pass argv as a pointer to NULL.
+ */
+
+	ldil	L%main,%r22
+	ble 	R%main(%sr4,%r22)
+	copy	%r31,%r2
+/*
+ * Call exit() from the C library with the return value from main()
+ */
+	copy	%r28,%r26
+	ldil	L%exit,%r22
+	ble	R%exit(%sr4,%r22)
+	copy	%r31,%r2
+
+        .PROCEND
+/*
+ * _exit -- Exit from the application. Normally we cause a user trap
+ * 	    to return to the ROM monitor for another run.
+ */
+	.EXPORT _exit, ENTRY
+_exit
+	.PROC
+	.CALLINFO
+	.ENTRY
+	
+	;; This just causes a breakpoint exception
+	break	0x0,0x0
+        bv,n    (%rp)
+	nop
+	.EXIT
+	.PROCEND
+
+/*
+ * _sr4export -- support for called functions. (mostly for GDB)
+ */
+	.EXPORT _sr4export, ENTRY
+_sr4export:
+	.PROC
+	.CALLINFO
+	.ENTRY
+
+	ble	0(%sr4,%r22)
+	copy	%r31,%rp
+	ldw	-24(%sr0,%sp),%rp
+	ldsid	(%sr0,%rp),%r1
+	mtsp	%r1,%sr0
+	be,n	0(%sr0,%rp)
+	nop
+	.EXIT
+	.PROCEND
+
+