calls.c (ECF_SP_DEPRESSED): New macro.

	* calls.c (ECF_SP_DEPRESSED): New macro.
	(calls_function_1): Treat calling sp-depressed function as alloca.
	(emit_call_1): Don't adjust SP if calling sp-depressed function.
	(expand_call): Set ECF_SP_DEPRESSED if TYPE_RETURNS_STACK_DEPRESSED.
	If sp-depressed, ensure block saves and restores SP.
	* fold-const.c (extract_muldiv): Only check TYPE_IS_SIZETYPE
	for INTEGER_TYPE.
	* function.c (keep_stack_depressed): New function.
	(thread_prologue_and_epilogue_insns): Call it.
	* print-tree.c (print_node): Use HOST_WIDE_INT_PRINT_UNSIGNED
	to print DECL_OFFSET_ALIGN.
	Print no-force-blk and transparent-union flags properly.
	* stmt.c (expand_goto_internal): Don't restore stack if last block
	and function returns with sp depressed.
	(fixup_gotos): Likewise.
	(save_stack_pointer): New function, from code in expand_decl.
	(expand_decl): Call new function.
	* tree.h (TYPE_IS_SIZETYPE): Call INTEGER_TYPE_CHECK.
	(TYPE_RETURNS_STACK_DEPRESSED): New macro.
	(save_stack_pointer): New declaration.

From-SVN: r35734

1 files changed, 32 insertions, 10 deletions

diff --git a/gcc/stmt.c b/gcc/stmt.c
index 38572ca..6ecfcd2 100644
--- a/gcc/stmt.c
+++ b/gcc/stmt.c
@@ -903,7 +903,15 @@ expand_goto_internal (body, label, last_insn)
 	     deleted as dead by flow.  */
 	  clear_pending_stack_adjust ();
 	  do_pending_stack_adjust ();
-	  emit_stack_restore (SAVE_BLOCK, stack_level, NULL_RTX);
+
+	  /* Don't do this adjust if it's to the end label and this function
+	     is to return with a depressed stack pointer.  */
+	  if (label == return_label
+	      && (TYPE_RETURNS_STACK_DEPRESSED
+		  (TREE_TYPE (current_function_decl))))
+	    ;
+	  else
+	    emit_stack_restore (SAVE_BLOCK, stack_level, NULL_RTX);
 	}
 
       if (body != 0 && DECL_TOO_LATE (body))
@@ -1182,7 +1190,10 @@ fixup_gotos (thisblock, stack_level, cleanup_list, first_insn, dont_jump_in)
 
 	  /* Restore stack level for the biggest contour that this
 	     jump jumps out of.  */
-	  if (f->stack_level)
+	  if (f->stack_level
+	      && ! (f->target_rtl == return_label
+		    && (TYPE_RETURNS_STACK_DEPRESSED 
+			(TREE_TYPE (current_function_decl)))))
 	    emit_stack_restore (SAVE_BLOCK, f->stack_level, f->before_jump);
 
 	  /* Finish up the sequence containing the insns which implement the
@@ -3667,6 +3678,23 @@ expand_end_bindings (vars, mark_ends, dont_jump_in)
   pop_temp_slots ();
 }
 
+/* Generate code to save the stack pointer at the start of the current block
+   and set up to restore it on exit.  */
+
+void
+save_stack_pointer ()
+{
+  struct nesting *thisblock = block_stack;
+
+  if (thisblock->data.block.stack_level == 0)
+    {
+      emit_stack_save (thisblock->next ? SAVE_BLOCK : SAVE_FUNCTION,
+		       &thisblock->data.block.stack_level,
+		       thisblock->data.block.first_insn);
+      stack_block_stack = thisblock;
+    }
+}
+
 /* Generate RTL for the automatic variable declaration DECL.
    (Other kinds of declarations are simply ignored if seen here.)  */
 
@@ -3777,14 +3805,8 @@ expand_decl (decl)
 
       /* Record the stack pointer on entry to block, if have
 	 not already done so.  */
-      if (thisblock->data.block.stack_level == 0)
-	{
-	  do_pending_stack_adjust ();
-	  emit_stack_save (thisblock->next ? SAVE_BLOCK : SAVE_FUNCTION,
-			   &thisblock->data.block.stack_level,
-			   thisblock->data.block.first_insn);
-	  stack_block_stack = thisblock;
-	}
+      do_pending_stack_adjust ();
+      save_stack_pointer ();
 
       /* In function-at-a-time mode, variable_size doesn't expand this,
 	 so do it now.  */