[PATCH] H8/300: Start-up code cleanup for H8/300H and newer

[Jan Dubiec]

This patch has been started as an attempt to fix assembler message about 
missing stack section attributes:
   CPPAS    libc/sys/h8300hms/crt0.o
../../../combosrc/newlib/libc/sys/h8300hms/crt0.S: Assembler messages:
../../../combosrc/newlib/libc/sys/h8300hms/crt0.S:64: Warning: new 
section '.stack' defined without attributes - this might cause problems

In the process I have noticed that H8/300H, H8/300S and H8SX code does 
not support normal mode. So the patch does a few things: declares stack 
section in a proper way, merges H8/300H and H8/300S/SX parts of code 
into one and adds support for normal mode.

2025-07-19  Jan Dubiec  <jdx@o2.pl>

newlib/ChangeLog:

     * libc/sys/h8300hms/crt0.S: General cleanup: declare stack section
     in a proper way, merge H8/300H and H8/300S/SX parts of code into
     one, add support for normal mode.
-------------- next part --------------
 newlib/libc/sys/h8300hms/crt0.S | 80 +++++++++++++++++------------------------
 1 file changed, 32 insertions(+), 48 deletions(-)

diff --git a/newlib/libc/sys/h8300hms/crt0.S b/newlib/libc/sys/h8300hms/crt0.S
index 05634113c..757fb0477 100644
--- a/newlib/libc/sys/h8300hms/crt0.S
+++ b/newlib/libc/sys/h8300hms/crt0.S
@@ -1,4 +1,4 @@
-; h8/300 and h8/300h start up file.
+; H8/300, H8/300H, H8/300S and H8SX start up file.
 
 #include "setarch.h"
 
@@ -10,90 +10,74 @@ _start:
 	mov.w	#_stack,sp
 	mov.w	#_edata,r0
 	mov.w	#_end,r2
-	sub.w   r1,r1
+	sub.w	r1,r1
 	sub.w	r0,r2
 	jsr	@_memset
 #ifdef __ELF__
-	mov.l   #__fini,r0
-	jsr     @_atexit
+	mov.w	#__fini,r0
+	jsr	@_atexit
 #ifdef __SIMULATOR__
-        jsr     @0xcc
+	jsr	@0xcc
 #endif
-	jsr     @__init
+	jsr	@__init
 #else
 #ifdef __SIMULATOR__
-        jsr     @0xcc
+	jsr	@0xcc
 #endif
 	jsr	@___main
 #endif
 	jsr	@_main
 	jsr	@_exit
 
-	.section .stack
-_stack:	.word 	1
+	.section .stack, "aw", @nobits
+_stack:	.space	2
 
 #endif
 
-#ifdef __H8300H__
+#if defined (__H8300H__) || defined (__H8300S__) || defined (__H8300SX__)
 
 	.section .text
 	.global	_start
 _start:
+#ifdef __NORMAL_MODE__
+	mov.w	#_stack,sp
+	mov.w	#_edata,r0
+	mov.w	#_end,r2
+	sub.l	er1,er1
+	sub.w	r0,r2
+#else
 	mov.l	#_stack,sp
 	mov.l	#_edata,er0
 	mov.l	#_end,er2
-	sub.w   r1,r1
+	sub.l	er1,er1
 	sub.l	er0,er2
+#endif
 	jsr	@_memset
 #ifdef __ELF__
-	mov.l   #__fini,er0
-	jsr     @_atexit
-#ifdef __SIMULATOR__
-        jsr     @0xcc
-#endif
-	jsr     @__init
+#ifdef __NORMAL_MODE__
+	mov.w	#__fini,r0
 #else
-#ifdef __SIMULATOR__
-        jsr     @0xcc
-#endif
-	jsr	@___main
+	mov.l	#__fini,er0
 #endif
-	jsr	@_main
-	jsr	@_exit
-
-	.section .stack
-_stack:	.long 	1
-
-#endif
-
-#if defined (__H8300S__) || defined (__H8300SX__)
-
-	.section .text
-	.global	_start
-_start:
-	mov.l	#_stack,sp
-	mov.l	#_edata,er0
-	mov.l	#_end,er2
-	sub.w   r1,r1
-	sub.l	er0,er2
-	jsr	@_memset
-#ifdef __ELF__
-	mov.l   #__fini,er0
-	jsr     @_atexit
+	jsr	@_atexit
 #ifdef __SIMULATOR__
-        jsr     @0xcc
+	jsr	@0xcc
 #endif
-	jsr     @__init
+	jsr	@__init
 #else
 #ifdef __SIMULATOR__
-        jsr     @0xcc
+	jsr	@0xcc
 #endif
 	jsr	@___main
 #endif
 	jsr	@_main
 	jsr	@_exit
 
-	.section .stack
-_stack:	.long 	1
+	.section .stack, "aw", @nobits
+#ifdef __NORMAL_MODE__
+_stack:	.space	2
+#else
+_stack:	.space	4
+#endif
 
 #endif