libgloss/

	* m68k/Makefile.in (bdm-semihost.o): Build from bdm-semihost.S.
	* m68k/bdm-semihost.c: Remove.
	* m68k/bdm-semihost.S: New.
	* m68k/bdm-crt0.S: Don't install semihosting trap handler.
	* m68k/bdm-close.c, bdm-exit.c, bdm-fstat.c, bdm-gettimeofday.c,
	bdm-isatty.c, bdm-lseek.c, bdm-open.c, bdm-read.c, bdm-rename.c,
	bdm-stat.c, bdm-system.c, bdm-unlink.c, bdm-write.c): Update.
	* m68k/bdm-isrs.c: Update comment.
	* m68k/bdm-semihost.h (BDM_TRAPNUM, BDM_FUNC_REG, BDM_ARG_REG,
	BDM_TRAP): Remove.
	(__bdm_semihost): Declare.

19 files changed, 54 insertions, 56 deletions

diff --git a/ChangeLog.csl b/ChangeLog.csl
index 6fe9d6c2d..f8072bfb7 100644
--- a/ChangeLog.csl
+++ b/ChangeLog.csl
@@ -1,3 +1,18 @@
+2006-09-18  Nathan Sidwell  <nathan@codesourcery.com>
+
+	libgloss/
+	* m68k/Makefile.in (bdm-semihost.o): Build from bdm-semihost.S.
+	* m68k/bdm-semihost.c: Remove.
+	* m68k/bdm-semihost.S: New.
+	* m68k/bdm-crt0.S: Don't install semihosting trap handler.
+	* m68k/bdm-close.c, bdm-exit.c, bdm-fstat.c, bdm-gettimeofday.c,
+	bdm-isatty.c, bdm-lseek.c, bdm-open.c, bdm-read.c, bdm-rename.c,
+	bdm-stat.c, bdm-system.c, bdm-unlink.c, bdm-write.c): Update.
+	* m68k/bdm-isrs.c: Update comment.
+	* m68k/bdm-semihost.h (BDM_TRAPNUM, BDM_FUNC_REG, BDM_ARG_REG,
+	BDM_TRAP): Remove.
+	(__bdm_semihost): Declare.
+
 2006-09-15  Nathan Sidwell  <nathan@codesourcery.com>
 
 	libgloss/
diff --git a/libgloss/m68k/Makefile.in b/libgloss/m68k/Makefile.in
index 29492e34c..150a8c31e 100644
--- a/libgloss/m68k/Makefile.in
+++ b/libgloss/m68k/Makefile.in
@@ -124,10 +124,10 @@ BDM_CRT0=	bdm-crt0.o
 BDM_BSP=	libbdm.a
 BDM_OBJS=	bdm-crt1.o bdm-semihost.o $(BDM_SYSOBJS) \
 		$(patsubst %,bdm-%.o,${BDM_ISRS})
-BDM_OTHER_OBJS=	getpid.o kill.o sbrk.o
+BDM_OTHER_OBJS=	getpid.o kill.o
 BDM_SYSOBJS= 	bdm-close.o bdm-exit.o bdm-fstat.o bdm-gdb.o \
 		bdm-gettimeofday.o bdm-isatty.o bdm-lseek.o \
-		bdm-open.o bdm-read.o bdm-rename.o \
+		bdm-open.o bdm-read.o bdm-rename.o bdm-sbrk.o \
 		bdm-stat.o bdm-system.o bdm-time.o bdm-unlink.o bdm-write.o
 BDM_ISRS=	other_interrupt reset access_error address_error \
 	illegal_instruction divide_by_zero privilege_violation \
@@ -193,9 +193,8 @@ bdm-crt0.o : bdm-crt0.S
 	$(CC) $(CFLAGS_FOR_TARGET) $(INCLUDES) -c $< -o $@
 bdm-crt1.o : bdm-crt1.c
 	$(CC) $(CFLAGS_FOR_TARGET) $(INCLUDES) -c $< -o $@
-#We need to omit the frame pointer to ensure there is no prologue.
-bdm-semihost.o : bdm-semihost.c
-	$(CC) $(CFLAGS_FOR_TARGET) $(INCLUDES) -c $< -o $@ -fomit-frame-pointer
+bdm-semihost.o : bdm-semihost.S
+	$(CC) $(CFLAGS_FOR_TARGET) $(INCLUDES) -c $< -o $@
 
 # We need to keep the frame pointer to make sure there's some
 # prologue.  Otherwise we get confused with the semihosting reoutine.
diff --git a/libgloss/m68k/bdm-close.c b/libgloss/m68k/bdm-close.c
index 40ddf9f5e..dced304b9 100644
--- a/libgloss/m68k/bdm-close.c
+++ b/libgloss/m68k/bdm-close.c
@@ -32,7 +32,7 @@ int close (int fd)
 {
   gdb_parambuf_t parameters;
   parameters[0] = (uint32_t) fd;
-  BDM_TRAP (BDM_CLOSE, (uint32_t)parameters);
+  __bdm_semihost (BDM_CLOSE, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }
diff --git a/libgloss/m68k/bdm-crt0.S b/libgloss/m68k/bdm-crt0.S
index dac6ac421..a61919a4f 100644
--- a/libgloss/m68k/bdm-crt0.S
+++ b/libgloss/m68k/bdm-crt0.S
@@ -55,7 +55,7 @@ __interrupt_vector:
 	.long __trap12				/* 44 */
 	.long __trap13				/* 45 */
 	.long __trap14				/* 46 */
-	.long __bdm_semihosting			/* 47 */
+	.long __trap15				/* 47 */
 	.long __fp_branch_unordered		/* 48 */
 	.long __fp_inexact_result		/* 49 */
 	.long __fp_divide_by_zero		/* 50 */
diff --git a/libgloss/m68k/bdm-exit.c b/libgloss/m68k/bdm-exit.c
index 5223bcd37..128d54710 100644
--- a/libgloss/m68k/bdm-exit.c
+++ b/libgloss/m68k/bdm-exit.c
@@ -27,7 +27,7 @@ void __attribute__ ((noreturn)) _exit (int code)
 {
   while (1)
     {
-      BDM_TRAP (BDM_EXIT, code);
+      __bdm_semihost (BDM_EXIT, (void *)code);
       __reset ();
     }
 }
diff --git a/libgloss/m68k/bdm-fstat.c b/libgloss/m68k/bdm-fstat.c
index f93f854f6..e8fb67619 100644
--- a/libgloss/m68k/bdm-fstat.c
+++ b/libgloss/m68k/bdm-fstat.c
@@ -37,7 +37,7 @@ int fstat (int fd, struct stat *buf)
   struct gdb_stat gbuf;
   parameters[0] = (uint32_t) fd;
   parameters[1] = (uint32_t) &gbuf;
-  BDM_TRAP (BDM_FSTAT, (uint32_t)parameters);
+  __bdm_semihost (BDM_FSTAT, parameters);
   convert_from_gdb_stat (&gbuf, buf);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
diff --git a/libgloss/m68k/bdm-gettimeofday.c b/libgloss/m68k/bdm-gettimeofday.c
index 154954244..5ed1331f8 100644
--- a/libgloss/m68k/bdm-gettimeofday.c
+++ b/libgloss/m68k/bdm-gettimeofday.c
@@ -40,7 +40,7 @@ int gettimeofday (struct timeval *tv, struct timezone *tz)
       return -1;
     }
   parameters[0] = (uint32_t) &gtv;
-  BDM_TRAP (BDM_GETTIMEOFDAY, (uint32_t)parameters);
+  __bdm_semihost (BDM_GETTIMEOFDAY, parameters);
   convert_from_gdb_timeval (&gtv, tv);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
diff --git a/libgloss/m68k/bdm-isatty.c b/libgloss/m68k/bdm-isatty.c
index 1da79bc15..81cad1cdb 100644
--- a/libgloss/m68k/bdm-isatty.c
+++ b/libgloss/m68k/bdm-isatty.c
@@ -32,7 +32,7 @@ int isatty (int fd)
 {
   gdb_parambuf_t parameters;
   parameters[0] = (uint32_t) fd;
-  BDM_TRAP (BDM_ISATTY, (uint32_t)parameters);
+  __bdm_semihost (BDM_ISATTY, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }
diff --git a/libgloss/m68k/bdm-isrs.c b/libgloss/m68k/bdm-isrs.c
index 7ee9fbaa0..2b80d6691 100644
--- a/libgloss/m68k/bdm-isrs.c
+++ b/libgloss/m68k/bdm-isrs.c
@@ -20,10 +20,7 @@
 
    These interrupt handlers are entered whenever the associated
    interrupt occurs.  All they do is stop the debugger to give the user
-   the opportunity to determine where the problem was.
-  
-   User trap BDM_TRAPNUM (15) is used for semi hosting support.
-   If you replace this one, semihosting will cease to function. */
+   the opportunity to determine where the problem was.  */
 
 
 /* Each ISR is a loop containing a halt instruction  */
diff --git a/libgloss/m68k/bdm-lseek.c b/libgloss/m68k/bdm-lseek.c
index b8308cbff..2ae7d667e 100644
--- a/libgloss/m68k/bdm-lseek.c
+++ b/libgloss/m68k/bdm-lseek.c
@@ -40,7 +40,7 @@ off_t lseek (int fd, off_t offset, int whence)
   parameters[1] = (uint32_t) ((offset >> 32) & 0xffffffff);
   parameters[2] = (uint32_t) (offset & 0xffffffff);
   parameters[3] = convert_to_gdb_lseek_flags (whence);
-  BDM_TRAP (BDM_LSEEK, (uint32_t)parameters);
+  __bdm_semihost (BDM_LSEEK, parameters);
   errno = convert_from_gdb_errno (parameters[2]);
   return ((uint64_t)parameters[0] << 32) | ((uint64_t)parameters[1]);
 }
diff --git a/libgloss/m68k/bdm-open.c b/libgloss/m68k/bdm-open.c
index 878cff84d..10e9148ad 100644
--- a/libgloss/m68k/bdm-open.c
+++ b/libgloss/m68k/bdm-open.c
@@ -50,7 +50,7 @@ int open (const char *fname, int flags, ...)
     }
   else
     parameters[3] = 0;
-  BDM_TRAP (BDM_OPEN, (uint32_t)parameters);
+  __bdm_semihost (BDM_OPEN, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }
diff --git a/libgloss/m68k/bdm-read.c b/libgloss/m68k/bdm-read.c
index 441a7d249..805feeb5b 100644
--- a/libgloss/m68k/bdm-read.c
+++ b/libgloss/m68k/bdm-read.c
@@ -36,7 +36,7 @@ ssize_t read (int fd, void *buf, size_t count)
   parameters[0] = (uint32_t) fd;
   parameters[1] = (uint32_t) buf;
   parameters[2] = (uint32_t) count;
-  BDM_TRAP (BDM_READ, (uint32_t)parameters);
+  __bdm_semihost (BDM_READ, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }
diff --git a/libgloss/m68k/bdm-rename.c b/libgloss/m68k/bdm-rename.c
index 3e0acf3bb..2698b7290 100644
--- a/libgloss/m68k/bdm-rename.c
+++ b/libgloss/m68k/bdm-rename.c
@@ -39,7 +39,7 @@ int _rename (const char *oldpath, const char *newpath)
   parameters[1] = (uint32_t) strlen (oldpath) + 1;
   parameters[2] = (uint32_t) newpath;
   parameters[3] = (uint32_t) strlen (newpath) + 1;
-  BDM_TRAP (BDM_RENAME, (uint32_t)parameters);
+  __bdm_semihost (BDM_RENAME, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }
diff --git a/libgloss/m68k/bdm-semihost.c b/libgloss/m68k/bdm-semihost.S
index c0608e1fa..26336eb6a 100644
--- a/libgloss/m68k/bdm-semihost.c
+++ b/libgloss/m68k/bdm-semihost.S
@@ -1,5 +1,5 @@
 /*
- * bdm-semihost.c -- 
+ * bdm-semihost.S -- 
  *
  * Copyright (c) 2006 CodeSourcery Inc
  *
@@ -14,12 +14,22 @@
  * they apply.
  */
 
-/* Semihosting trap.  The debugger intercepts this and
-   performs the semihosting action.  Then the program resumes as
-   usual.  This function must be compiled without a frame pointer, so
-   we know the halt instruction is the very first instuction.  */
+/* Semihosting function.  The debugger intercepts the halt, and
+   determines that it is followed by the magic movec pattern. */
+
+	.globl __bdm_semihost
+__bdm_semihost:
+	linkw %fp,#0
+	movel %fp@(8),%d0
+	movel %fp@(12),%d1
+	.align 4
+	nop
+	halt
+	
+	/* This sentinel instruction value must be aligned to a 4 byte
+	 * boundary and be immediately after the halt instruction.  The
+	 * debugger will adjust the pc, so that it is never executed.  */
 	
-void __attribute__ ((interrupt_handler)) __bdm_semihosting (void) 
-{
-  __asm__ __volatile__ ("halt" ::: "memory");
-}
+	.long 0x4e7b0000
+	unlk %fp
+	rts
diff --git a/libgloss/m68k/bdm-semihost.h b/libgloss/m68k/bdm-semihost.h
index 4d6e2b9cc..d82027557 100644
--- a/libgloss/m68k/bdm-semihost.h
+++ b/libgloss/m68k/bdm-semihost.h
@@ -14,21 +14,6 @@
  * they apply.
  */
 
-/* Semihosting uses a user trap handler containing a HALT
-   instruction.  This wakes the debugger to perform some action.  */
-
-/* This is the semihosting trap hander */
-#define BDM_TRAPNUM 15
-
-/* This register holds the function enumeration for a semihosting
-   command.  */
-#define BDM_FUNC_REG "d0"
-
-/* This register holds the argument for the semihosting call.  For most
-   functions, this is a pointer to a block of memory that holds the input
-   and output parameters for the remote file i/o operation.  */
-#define BDM_ARG_REG  "d1"
-
 /* Codes for BDM_FUNC_REG.  */
 
 #define BDM_EXIT  0
@@ -46,12 +31,4 @@
 #define BDM_ISATTY 12
 #define BDM_SYSTEM 13
 
-/* Here is the macro that generates the trap. */
-
-#define BDM_TRAP(func, arg) \
-  __asm__ __volatile__ ("move.l %0,%/" BDM_ARG_REG "\n" \
-			"moveq %1,%/" BDM_FUNC_REG "\n" \
-			"trap %2" \
-			:: "rmi" (arg), "n" (func), "n" (BDM_TRAPNUM) \
-			: BDM_FUNC_REG,BDM_ARG_REG,"memory")
-
+extern int __bdm_semihost (int func, void *args);
diff --git a/libgloss/m68k/bdm-stat.c b/libgloss/m68k/bdm-stat.c
index 536aeec5d..21c0ca3e5 100644
--- a/libgloss/m68k/bdm-stat.c
+++ b/libgloss/m68k/bdm-stat.c
@@ -41,7 +41,7 @@ int stat (const char *filename, struct stat *buf)
   parameters[0] = (uint32_t) filename;
   parameters[1] = (uint32_t) strlen (filename) + 1;
   parameters[2] = (uint32_t) &gbuf;
-  BDM_TRAP (BDM_STAT, (uint32_t)parameters);
+  __bdm_semihost (BDM_STAT, parameters);
   convert_from_gdb_stat (&gbuf, buf);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
diff --git a/libgloss/m68k/bdm-system.c b/libgloss/m68k/bdm-system.c
index 75a82e2a7..6aab4b1ef 100644
--- a/libgloss/m68k/bdm-system.c
+++ b/libgloss/m68k/bdm-system.c
@@ -37,7 +37,7 @@ int _system (const char *command)
   
   parameters[0] = (uint32_t) command;
   parameters[1] = command ? (uint32_t) strlen (command) + 1 : 0;
-  BDM_TRAP (BDM_SYSTEM, (uint32_t)parameters);
+  __bdm_semihost (BDM_SYSTEM, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   e = parameters[0];
   if (e >= 0 && command)
diff --git a/libgloss/m68k/bdm-unlink.c b/libgloss/m68k/bdm-unlink.c
index 05098ae7a..29f807204 100644
--- a/libgloss/m68k/bdm-unlink.c
+++ b/libgloss/m68k/bdm-unlink.c
@@ -35,7 +35,7 @@ int unlink (const char *path)
   gdb_parambuf_t parameters;
   parameters[0] = (uint32_t) path;
   parameters[1] = (uint32_t) strlen (path) + 1;
-  BDM_TRAP (BDM_UNLINK, (uint32_t)parameters);
+  __bdm_semihost (BDM_UNLINK, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }
diff --git a/libgloss/m68k/bdm-write.c b/libgloss/m68k/bdm-write.c
index 0280dcd7c..b532e4cb3 100644
--- a/libgloss/m68k/bdm-write.c
+++ b/libgloss/m68k/bdm-write.c
@@ -36,7 +36,7 @@ ssize_t write (int fd, const void *buf, size_t count)
   parameters[0] = (uint32_t) fd;
   parameters[1] = (uint32_t) buf;
   parameters[2] = (uint32_t) count;
-  BDM_TRAP (BDM_WRITE, (uint32_t)parameters);
+  __bdm_semihost (BDM_WRITE, parameters);
   errno = convert_from_gdb_errno (parameters[1]);
   return parameters[0];
 }