expr.c (STACK_BYTES): Delete unused macro.

	* expr.c (STACK_BYTES): Delete unused macro.
	* calls.c: Provide default for PREFERRED_STACK_BOUNDARY.
	(STACK_BYTES): Use PREFERRED_STACK_BOUNDARY, not STACK_BOUNDARY.
	(expand_call): Likewise.
	(emit_library_call): Likewise.
	(emit_library_call_value): Likewise.
	* function.c: Provide default for PREFERRED_STACK_BOUNDARY.
	(STACK_BYTES): Use PREFERRED_STACK_BOUNDARY, not STACK_BOUNDARY.
	* explow.c: Provide default for PREFERRED_STACK_BOUNDARY.
	(round_push): Use PREFERRED_STACK_BOUNDARY, not STACK_BOUNDARY.
	(allocate_dynamic_stack_space): Likewise.
	* tm.texi (PREFERRED_STACK_BOUNDARY): Document new macro.
	(STACK_BOUNDARY): Update description to reflect the new situation.

From-SVN: r23730

6 files changed, 68 insertions, 34 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 92ae27a..fff326d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,19 @@
+Thu Nov 19 23:44:38 1998  Bernd Schmidt <crux@pool.informatik.rwth-aachen.de>
+
+	* expr.c (STACK_BYTES): Delete unused macro.
+	* calls.c: Provide default for PREFERRED_STACK_BOUNDARY.
+	(STACK_BYTES): Use PREFERRED_STACK_BOUNDARY, not STACK_BOUNDARY.
+	(expand_call): Likewise.
+	(emit_library_call): Likewise.
+	(emit_library_call_value): Likewise.
+	* function.c: Provide default for PREFERRED_STACK_BOUNDARY.
+	(STACK_BYTES): Use PREFERRED_STACK_BOUNDARY, not STACK_BOUNDARY.
+	* explow.c: Provide default for PREFERRED_STACK_BOUNDARY.
+	(round_push): Use PREFERRED_STACK_BOUNDARY, not STACK_BOUNDARY.
+	(allocate_dynamic_stack_space): Likewise.
+	* tm.texi (PREFERRED_STACK_BOUNDARY): Document new macro.
+	(STACK_BOUNDARY): Update description to reflect the new situation.
+
 Thu Nov 19 22:20:51 1998  Jeffrey A Law  (law@cygnus.com)
 
 	* reorg.c (relax_delay_slots): When optimizing for code size, if a
diff --git a/gcc/calls.c b/gcc/calls.c
index fb64c75..6f67b7c 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -29,6 +29,10 @@ Boston, MA 02111-1307, USA.  */
 #include "toplev.h"
 #include "output.h"
 
+#if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
+#define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
+#endif
+
 /* Decide whether a function's arguments should be processed
    from first to last or from last to first.
 
@@ -43,8 +47,8 @@ Boston, MA 02111-1307, USA.  */
 
 #endif
 
-/* Like STACK_BOUNDARY but in units of bytes, not bits.  */
-#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
+/* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits.  */
+#define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
 
 /* Data structure and subroutines used within expand_call.  */
 
@@ -311,7 +315,7 @@ prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
    says that the pointer to this aggregate is to be popped by the callee.
 
    STACK_SIZE is the number of bytes of arguments on the stack,
-   rounded up to STACK_BOUNDARY; zero if the size is variable.
+   rounded up to PREFERRED_STACK_BOUNDARY; zero if the size is variable.
    This is both to put into the call insn and
    to generate explicit popping code if necessary.
 
@@ -1240,8 +1244,8 @@ expand_call (exp, target, ignore)
       args_size.var = ARGS_SIZE_TREE (args_size);
       args_size.constant = 0;
 
-#ifdef STACK_BOUNDARY
-      if (STACK_BOUNDARY != BITS_PER_UNIT)
+#ifdef PREFERRED_STACK_BOUNDARY
+      if (PREFERRED_STACK_BOUNDARY != BITS_PER_UNIT)
 	args_size.var = round_up (args_size.var, STACK_BYTES);
 #endif
 
@@ -1262,7 +1266,7 @@ expand_call (exp, target, ignore)
     }
   else
     {
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
       args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
 			     / STACK_BYTES) * STACK_BYTES);
 #endif
@@ -1589,7 +1593,7 @@ expand_call (exp, target, ignore)
     }
 					       
 #ifdef PUSH_ARGS_REVERSED
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we push args individually in reverse order, perform stack alignment
      before the first push (the last arg).  */
   if (argblock == 0)
@@ -1838,7 +1842,7 @@ expand_call (exp, target, ignore)
 		       args_size.var != 0, reg_parm_stack_space);
 
 #ifndef PUSH_ARGS_REVERSED
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we pushed args in forward order, perform stack alignment
      after pushing the last arg.  */
   if (argblock == 0)
@@ -2386,7 +2390,7 @@ emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
   assemble_external_libcall (fun);
 
   original_args_size = args_size;
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
 			 / STACK_BYTES) * STACK_BYTES);
 #endif
@@ -2454,7 +2458,7 @@ emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
 #endif
 
 #ifdef PUSH_ARGS_REVERSED
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we push args individually in reverse order, perform stack alignment
      before the first push (the last arg).  */
   if (argblock == 0)
@@ -2599,7 +2603,7 @@ emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
     }
 
 #ifndef PUSH_ARGS_REVERSED
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we pushed args in forward order, perform stack alignment
      after pushing the last arg.  */
   if (argblock == 0)
@@ -2950,7 +2954,7 @@ emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
   assemble_external_libcall (fun);
 
   original_args_size = args_size;
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
 			 / STACK_BYTES) * STACK_BYTES);
 #endif
@@ -3018,7 +3022,7 @@ emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
 #endif
 
 #ifdef PUSH_ARGS_REVERSED
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we push args individually in reverse order, perform stack alignment
      before the first push (the last arg).  */
   if (argblock == 0)
@@ -3164,7 +3168,7 @@ emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
     }
 
 #ifndef PUSH_ARGS_REVERSED
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we pushed args in forward order, perform stack alignment
      after pushing the last arg.  */
   if (argblock == 0)
diff --git a/gcc/explow.c b/gcc/explow.c
index 95fb561..0dbf002 100644
--- a/gcc/explow.c
+++ b/gcc/explow.c
@@ -31,6 +31,10 @@ Boston, MA 02111-1307, USA.  */
 #include "insn-flags.h"
 #include "insn-codes.h"
 
+#if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
+#define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
+#endif
+
 static rtx break_out_memory_refs	PROTO((rtx));
 static void emit_stack_probe		PROTO((rtx));
 /* Return an rtx for the sum of X and the integer C.
@@ -830,8 +834,8 @@ rtx
 round_push (size)
      rtx size;
 {
-#ifdef STACK_BOUNDARY
-  int align = STACK_BOUNDARY / BITS_PER_UNIT;
+#ifdef PREFERRED_STACK_BOUNDARY
+  int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
   if (align == 1)
     return size;
   if (GET_CODE (size) == CONST_INT)
@@ -851,7 +855,7 @@ round_push (size)
 			    NULL_RTX, 1);
       size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1);
     }
-#endif /* STACK_BOUNDARY */
+#endif /* PREFERRED_STACK_BOUNDARY */
   return size;
 }
 
@@ -1124,10 +1128,10 @@ allocate_dynamic_stack_space (size, target, known_align)
      If we have to align, we must leave space in SIZE for the hole
      that might result from the alignment operation.  */
 
-#if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (STACK_BOUNDARY)
+#if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (PREFERRED_STACK_BOUNDARY)
 #define MUST_ALIGN 1
 #else
-#define MUST_ALIGN (STACK_BOUNDARY < BIGGEST_ALIGNMENT)
+#define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
 #endif
 
   if (MUST_ALIGN)
@@ -1154,12 +1158,12 @@ allocate_dynamic_stack_space (size, target, known_align)
 
     if (!current_function_calls_setjmp)
       {
-	int align = STACK_BOUNDARY / BITS_PER_UNIT;
+	int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
 
 	/* See optimize_save_area_alloca to understand what is being
 	   set up here.  */
 
-#if !defined(STACK_BOUNDARY) || !defined(MUST_ALIGN) || (STACK_BOUNDARY != BIGGEST_ALIGNMENT)
+#if !defined(PREFERRED_STACK_BOUNDARY) || !defined(MUST_ALIGN) || (PREFERRED_STACK_BOUNDARY != BIGGEST_ALIGNMENT)
 	/* If anyone creates a target with these characteristics, let them
 	   know that our optimization cannot work correctly in such a case.  */
 	abort();
@@ -1209,11 +1213,11 @@ allocate_dynamic_stack_space (size, target, known_align)
      way of knowing which systems have this problem.  So we avoid even
      momentarily mis-aligning the stack.  */
 
-#ifdef STACK_BOUNDARY
+#ifdef PREFERRED_STACK_BOUNDARY
   /* If we added a variable amount to SIZE,
      we can no longer assume it is aligned.  */
 #if !defined (SETJMP_VIA_SAVE_AREA)
-  if (MUST_ALIGN || known_align % STACK_BOUNDARY != 0)
+  if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0)
 #endif
     size = round_push (size);
 #endif
diff --git a/gcc/expr.c b/gcc/expr.c
index 3d46dea..ca0aba1 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -65,9 +65,6 @@ Boston, MA 02111-1307, USA.  */
 #endif
 #endif
 
-/* Like STACK_BOUNDARY but in units of bytes, not bits.  */
-#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
-
 /* Assume that case vectors are not pc-relative.  */
 #ifndef CASE_VECTOR_PC_RELATIVE
 #define CASE_VECTOR_PC_RELATIVE 0
diff --git a/gcc/function.c b/gcc/function.c
index 3f47848..fa8b14a 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -57,6 +57,10 @@ Boston, MA 02111-1307, USA.  */
 #include "obstack.h"
 #include "toplev.h"
 
+#if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
+#define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
+#endif
+
 #ifndef TRAMPOLINE_ALIGNMENT
 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
 #endif
@@ -669,7 +673,7 @@ void pop_function_context ()
 /* Allocate fixed slots in the stack frame of the current function.  */
 
 /* Return size needed for stack frame based on slots so far allocated.
-   This size counts from zero.  It is not rounded to STACK_BOUNDARY;
+   This size counts from zero.  It is not rounded to PREFERRED_STACK_BOUNDARY;
    the caller may have to do that.  */
 
 HOST_WIDE_INT
@@ -4645,8 +4649,8 @@ assign_parms (fndecl, second_time)
 #endif
 #endif
 
-#ifdef STACK_BOUNDARY
-#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
+#ifdef PREFERRED_STACK_BOUNDARY
+#define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
 
   current_function_args_size
     = ((current_function_args_size + STACK_BYTES - 1)
diff --git a/gcc/tm.texi b/gcc/tm.texi
index ab35f1f..7a0dd0e 100644
--- a/gcc/tm.texi
+++ b/gcc/tm.texi
@@ -790,15 +790,24 @@ size of an integer.
 
 @findex STACK_BOUNDARY
 @item STACK_BOUNDARY
+Define this macro if there is a guaranteed alignment for the stack
+pointer on this machine.  The definition is a C expression
+for the desired alignment (measured in bits).  This value is used as a
+default if PREFERRED_STACK_BOUNDARY is not defined.
+
+@findex PREFERRED_STACK_BOUNDARY
+@item PREFERRED_STACK_BOUNDARY
 Define this macro if you wish to preserve a certain alignment for
 the stack pointer.  The definition is a C expression
-for the desired alignment (measured in bits).
+for the desired alignment (measured in bits).  If STACK_BOUNDARY is
+also defined, this macro must evaluate to a value equal to or larger
+than STACK_BOUNDARY.
 
-@cindex @code{PUSH_ROUNDING}, interaction with @code{STACK_BOUNDARY}
+@cindex @code{PUSH_ROUNDING}, interaction with @code{PREFERRED_STACK_BOUNDARY}
 If @code{PUSH_ROUNDING} is not defined, the stack will always be aligned
-to the specified boundary.  If @code{PUSH_ROUNDING} is defined and specifies a
-less strict alignment than @code{STACK_BOUNDARY}, the stack may be
-momentarily unaligned while pushing arguments.
+to the specified boundary.  If @code{PUSH_ROUNDING} is defined and specifies
+a less strict alignment than @code{PREFERRED_STACK_BOUNDARY}, the stack may
+be momentarily unaligned while pushing arguments.
 
 @findex FUNCTION_BOUNDARY
 @item FUNCTION_BOUNDARY