Stack usage support

	* common.opt (-fstack-usage): New option.
	* doc/invoke.texi (Debugging options): Document it.
	* builtins.c (expand_builtin_apply): Pass TRUE as 4th argument to
	allocate_dynamic_stack_space.
	(expand_builtin_alloca): Add 4th bool parameter CANNOT_ACCUMULATE
	and propagate it to allocate_dynamic_stack_space.
	(expand_builtin) <BUILT_IN_ALLOCA>: Adjust for above change.
	* calls.c (initialize_argument_information): Pass TRUE as 4th
	argument to allocate_dynamic_stack_space.
	(expand_call): Set current_function_has_unbounded_dynamic_stack_size
	to 1 when pushing a variable-sized argument onto the stack.  Pass
	TRUE as 4th argument to allocate_dynamic_stack_space.
	Update current_function_pushed_stack_size.
	(emit_library_call_value_1): Likewise.
	* explow.c (allocate_dynamic_stack_space): Add 4th bool parameter
	CANNOT_ACCUMULATE.  If flag_stack_usage, look into the size and
	attempt to find an upper bound.  Remove redundant code for the
	SETJMP_VIA_SAVE_AREA case.
	* expr.h (allocate_dynamic_stack_space): Add 4th bool parameter.
	* function.h (struct stack_usage): New structure.
	(current_function_static_stack_size): New macro.
	(current_function_dynamic_stack_size): Likewise.
	(current_function_pushed_stack_size): Likewise.
	(current_function_dynamic_alloc_count): Likewise.
	(current_function_has_unbounded_dynamic_stack_size): Likewise.
	(current_function_allocates_dynamic_stack_space): Likewise.
	(struct function): Add new field 'su'.
	* function.c (instantiate_virtual_regs): If SETJMP_VIA_SAVE_AREA,
	add the value of the dynamic offset to the dynamic stack usage.
	(gimplify_parameters): Set ALLOCA_FOR_VAR_P on call to BUILT_IN_ALLOCA
	for variable-sized objects.
	(prepare_function_start): Allocate cfun->su if flag_stack_usage.
	(rest_of_handle_thread_prologue_and_epilogue): Call output_stack_usage.
	* gimplify.c (gimplify_decl_expr): Set ALLOCA_FOR_VAR_P on call to
	BUILT_IN_ALLOCA for variable-sized objects.
	* output.h (output_stack_usage): Declare.
	* toplev.c (stack_usage_file): New file pointer.
	(output_stack_usage): New function.
	(open_auxiliary_file): Likewise.
	(lang_dependent_init): Open file if flag_stack_usage is set.
	(finalize): Close file if stack_usage_file is not null.
	* tree.h (ALLOCA_FOR_VAR_P): New macro.
	* config/alpha/alpha.c (compute_frame_size): New function.
	(alpha_expand_prologue): Use it.
	(alpha_start_function): Likewise.
	(alpha_expand_epilogue): Likewise.  Set stack usage info.
	* config/i386/i386.c (ix86_expand_prologue): Likewise.
	* config/ia64/ia64.c (ia64_expand_prologue): Likewise.
	* config/mips/mips.c (mips_expand_prologue): Likewise.
	* config/pa/pa.c (hppa_expand_prologue): Likewise.
	* config/rs6000/rs6000.c (rs6000_emit_prologue): Likewise.
	* config/sparc/sparc.c (sparc_expand_prologue): Likewise.
testsuite/
	* lib/gcc-dg.exp (cleanup-stack-usage): New procedure.
	* lib/scanasm.exp (scan-stack-usage): Likewise.
	(scan-stack-usage-not): Likewise.
	* gcc.dg/stack-usage-1.c: New test.
	* gcc.target/i386/stack-usage-realign.c: Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@163660 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 31 insertions, 2 deletions

diff --git a/gcc/calls.c b/gcc/calls.c
index c50a79265f0..7b6d113a5ec 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -1095,9 +1095,13 @@ initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
 		      pending_stack_adjust = 0;
 		    }
 
+		  /* We can pass TRUE as the 4th argument because we just
+		     saved the stack pointer and will restore it right after
+		     the call.  */
 		  copy = gen_rtx_MEM (BLKmode,
 				      allocate_dynamic_stack_space
-				      (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
+				      (size_rtx, NULL_RTX,
+				       TYPE_ALIGN (type), TRUE));
 		  set_mem_attributes (copy, type, 1);
 		}
 	      else
@@ -2492,6 +2496,8 @@ expand_call (tree exp, rtx target, int ignore)
 	      stack_arg_under_construction = 0;
 	    }
 	  argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
+	  if (flag_stack_usage)
+	    current_function_has_unbounded_dynamic_stack_size = 1;
 	}
       else
 	{
@@ -2653,8 +2659,11 @@ expand_call (tree exp, rtx target, int ignore)
 		  stack_usage_map = stack_usage_map_buf;
 		  highest_outgoing_arg_in_use = 0;
 		}
+	      /* We can pass TRUE as the 4th argument because we just
+		 saved the stack pointer and will restore it right after
+		 the call.  */
 	      allocate_dynamic_stack_space (push_size, NULL_RTX,
-					    BITS_PER_UNIT);
+					    BITS_PER_UNIT, TRUE);
 	    }
 
 	  /* If argument evaluation might modify the stack pointer,
@@ -2694,6 +2703,19 @@ expand_call (tree exp, rtx target, int ignore)
 	 be deferred during the evaluation of the arguments.  */
       NO_DEFER_POP;
 
+      /* Record the maximum pushed stack space size.  We need to delay
+	 doing it this far to take into account the optimization done
+	 by combine_pending_stack_adjustment_and_call.  */
+      if (flag_stack_usage
+	  && !ACCUMULATE_OUTGOING_ARGS
+	  && pass
+	  && adjusted_args_size.var == 0)
+	{
+	  int pushed = adjusted_args_size.constant + pending_stack_adjust;
+	  if (pushed > current_function_pushed_stack_size)
+	    current_function_pushed_stack_size = pushed;
+	}
+
       funexp = rtx_for_function_call (fndecl, addr);
 
       /* Figure out the register where the value, if any, will come back.  */
@@ -3551,6 +3573,13 @@ emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
   if (args_size.constant > crtl->outgoing_args_size)
     crtl->outgoing_args_size = args_size.constant;
 
+  if (flag_stack_usage && !ACCUMULATE_OUTGOING_ARGS)
+    {
+      int pushed = args_size.constant + pending_stack_adjust;
+      if (pushed > current_function_pushed_stack_size)
+	current_function_pushed_stack_size = pushed;
+    }
+
   if (ACCUMULATE_OUTGOING_ARGS)
     {
       /* Since the stack pointer will never be pushed, it is possible for