Correct fixes for various hot/cold partitioning concerns.

2005-04-27  Caroline Tice  <ctice@apple.com>

        * bb-reorder.c (find_rarely_executed_basic_blocks_and_crossing_edges):
        Remove targetm.have_named_sections test.
        (fix_edges_for_rarely_executed_code): Likewise.
        (insert_section_boundary_note): Likewise.
        (reorder_basic_blocks): Check partitioning flag before calling
        verify_hot_cold_block_grouping.
        * dbxout.c (dbxout_function_end): Get hot/cold section labels from
        the function struct rather than global variables.
        * dwarf2out.c (COLD_TEXT_SECTION_LABEL): New macro.
        (COLD_END_LABEL): Likewise
        (cold_text_section_label): New static global variable.
        (cold_end_label): Likewise.
        (dwarf2out_switch_text_section): Get hot/cold section labels from
        the function struct rather than global variables; test to make sure
        cfun is defined.
        (output_aranges): Use cold_text_section_label and cold_end_label;
        check partitioning flag before putting out delta.
        (output_ranges): Remove incorrect code attempting to use
        hot/cold labels.
        (output_line_info): Get cold section label from function struct; test
        to make sure cfun is defined.
        (add_location_or_const_value_attribute): Likewise.
        (dwarf2out_var_location): Likewise.
        (dwarf2out_init): Generate cold_text_section_label and cold_end_label;
        write out cold_text_section_label if partition flag is set.
        (dwarf2out_finish): Write out cold_end_label if partition flag is set;
        * function.h (struct function): Add new fields to point to hot/cold
        section labels: hot_section_label, cold_section_label,
        hot_section_end_label and cold_section_end_label; also add new field
        for cold text section name, unlikely_text_section_name.
        * opts.c (decode_options): Turn off partitioning flag if
        !targetm.have_named_sections.
        * output.h (hot_section_label): Remove.
        (hot_section_end_label): Remove.
        (cold_section_end_label): Remove.
        (unlikely_section_label): Remove.
        (unlikely_text_section_name): Remove.
        * passes.c (rest_of_handle_final):  Remove extra blank line.
        * varasm.c (unlikely_section_label): Remove.
        (hot_section_label): Remove.
        (hot_section_end_label): Remove.
        (cold_section_end_label): Remove.
        (unlikely_text_section_name):  Remove.
        (initialize_cold_section_name): Modify to call
        targetm.strip_name_encoding; to store cold section name in current
        function struct, if it exists; and to only use the decl_section_name
        if flag_named_sections is true.
        (unlikely_text_section): Modify to get section name out of current
        function struct, if there is one; otherwise build it from
        UNLIKELY_EXECUTED_TEXT_SECTION_NAME.
        (in_unlikely_text_section): Likewise.
        (named_section): Modify to get/put cold section name in current function
        struct, if there is one.
        (function_section):  Change 'bool unlikely' to 'int reloc'; check
        targetm.have_named_sections before calling named_section.
        (current_function_section): Likewise.
        (assemble_start_function): Modify to get/put unlikely_text_section_name
        in current function struct; modify to get hot/cold section labels
        from function struct; initialize labels using
        ASM_GENERATE_INTERNAL_LABEL;
        test partitioning flag before writing out hot section label.
        (assemble_end_function): Test partitioning flag before writing out
        hot/cold section labels.
        (default_section_type_flags_1):  Get cold text section name from
        function struct if there is one; Set flags correctly for
        cold text section if there is not a current function struct.

From-SVN: r98885

gcc/ChangeLog

+2005-04-27  Caroline Tice  <ctice@apple.com>
+
+        * bb-reorder.c (find_rarely_executed_basic_blocks_and_crossing_edges):
+	Remove targetm.have_named_sections test.
+	(fix_edges_for_rarely_executed_code): Likewise.
+	(insert_section_boundary_note): Likewise.
+	(reorder_basic_blocks): Check partitioning flag before calling
+	verify_hot_cold_block_grouping.
+	* dbxout.c (dbxout_function_end): Get hot/cold section labels from
+	the function struct rather than global variables.
+	* dwarf2out.c (COLD_TEXT_SECTION_LABEL): New macro.
+	(COLD_END_LABEL): Likewise
+	(cold_text_section_label): New static global variable.
+	(cold_end_label): Likewise.
+	(dwarf2out_switch_text_section): Get hot/cold section labels from
+	the function struct rather than global variables; test to make sure
+	cfun is defined.
+	(output_aranges): Use cold_text_section_label and cold_end_label;
+	check partitioning flag before putting out delta.
+	(output_ranges): Remove incorrect code attempting to use
+	hot/cold labels.
+	(output_line_info): Get cold section label from function struct; test
+	to make sure cfun is defined.
+	(add_location_or_const_value_attribute): Likewise.
+	(dwarf2out_var_location): Likewise.
+	(dwarf2out_init): Generate cold_text_section_label and cold_end_label;
+	write out cold_text_section_label if partition flag is set.
+	(dwarf2out_finish): Write out cold_end_label if partition flag is set;
+	* function.h (struct function): Add new fields to point to hot/cold
+	section labels: hot_section_label, cold_section_label,
+	hot_section_end_label and cold_section_end_label; also add new field
+	for cold text section name, unlikely_text_section_name.
+	* opts.c (decode_options): Turn off partitioning flag if
+	!targetm.have_named_sections.
+	* output.h (hot_section_label): Remove.
+	(hot_section_end_label): Remove.
+	(cold_section_end_label): Remove.
+	(unlikely_section_label): Remove.
+	(unlikely_text_section_name): Remove.
+	* passes.c (rest_of_handle_final):  Remove extra blank line.
+	* varasm.c (unlikely_section_label): Remove.
+	(hot_section_label): Remove.
+	(hot_section_end_label): Remove.
+	(cold_section_end_label): Remove.
+	(unlikely_text_section_name):  Remove.
+	(initialize_cold_section_name): Modify to call
+	targetm.strip_name_encoding; to store cold section name in current
+	function struct, if it exists; and to only use the decl_section_name
+	if flag_named_sections is true.
+	(unlikely_text_section): Modify to get section name out of current
+	function struct, if there is one; otherwise build it from
+	UNLIKELY_EXECUTED_TEXT_SECTION_NAME.
+	(in_unlikely_text_section): Likewise.
+	(named_section): Modify to get/put cold section name in current function
+	struct, if there is one.
+	(function_section):  Change 'bool unlikely' to 'int reloc'; check
+	targetm.have_named_sections before calling named_section.
+	(current_function_section): Likewise.
+	(assemble_start_function): Modify to get/put unlikely_text_section_name
+	in current function struct; modify to get hot/cold section labels
+	from function struct; initialize labels using
+	ASM_GENERATE_INTERNAL_LABEL;
+	test partitioning flag before writing out hot section label.
+	(assemble_end_function): Test partitioning flag before writing out
+	hot/cold section labels.
+	(default_section_type_flags_1):  Get cold text section name from
+	function struct if there is one; Set flags correctly for
+	cold text section if there is not a current function struct.
+	
 2005-04-27  Richard Guenther  <rguenth@gcc.gnu.org>
 
 	* tree-ssa-propagate.c (set_rhs): Revert last change.

gcc/bb-reorder.c

@@ -1237,27 +1237,24 @@ find_rarely_executed_basic_blocks_and_crossing_edges (edge *crossing_edges,
   /* Mark every edge that crosses between sections.  */
 
   i = 0;
-  if (targetm.have_named_sections)
+  FOR_EACH_BB (bb)
+    FOR_EACH_EDGE (e, ei, bb->succs)
     {
-      FOR_EACH_BB (bb)
-        FOR_EACH_EDGE (e, ei, bb->succs)
-	  {
-	    if (e->src != ENTRY_BLOCK_PTR
-		&& e->dest != EXIT_BLOCK_PTR
-		&& BB_PARTITION (e->src) != BB_PARTITION (e->dest))
-	      {
-		e->flags |= EDGE_CROSSING;
-		if (i == *max_idx)
-		  {
-		    *max_idx *= 2;
-		    crossing_edges = xrealloc (crossing_edges,
-					       (*max_idx) * sizeof (edge));
-		  }
-		crossing_edges[i++] = e;
-	      }
-	    else
-	      e->flags &= ~EDGE_CROSSING;
-	  }
+      if (e->src != ENTRY_BLOCK_PTR
+	  && e->dest != EXIT_BLOCK_PTR
+	  && BB_PARTITION (e->src) != BB_PARTITION (e->dest))
+	{
+	  e->flags |= EDGE_CROSSING;
+	  if (i == *max_idx)
+	    {
+	      *max_idx *= 2;
+	      crossing_edges = xrealloc (crossing_edges,
+					 (*max_idx) * sizeof (edge));
+	    }
+	  crossing_edges[i++] = e;
+	}
+      else
+	e->flags &= ~EDGE_CROSSING;
     }
   *n_crossing_edges = i;
 }
@@ -1821,36 +1818,26 @@ fix_edges_for_rarely_executed_code (edge *crossing_edges,
   
   fix_up_fall_thru_edges ();
   
-  /* Only do the parts necessary for writing separate sections if
-     the target architecture has the ability to write separate sections
-     (i.e. it has named sections).  Otherwise, the hot/cold partitioning
-     information will be used when reordering blocks to try to put all
-     the hot blocks together, then all the cold blocks, but no actual
-     section partitioning will be done.  */
-
-  if (targetm.have_named_sections)
-    {
-      /* If the architecture does not have conditional branches that can
-	 span all of memory, convert crossing conditional branches into
-	 crossing unconditional branches.  */
+  /* If the architecture does not have conditional branches that can
+     span all of memory, convert crossing conditional branches into
+     crossing unconditional branches.  */
   
-      if (!HAS_LONG_COND_BRANCH)
-	fix_crossing_conditional_branches ();
+  if (!HAS_LONG_COND_BRANCH)
+    fix_crossing_conditional_branches ();
   
-      /* If the architecture does not have unconditional branches that
-	 can span all of memory, convert crossing unconditional branches
-	 into indirect jumps.  Since adding an indirect jump also adds
-	 a new register usage, update the register usage information as
-	 well.  */
-      
-      if (!HAS_LONG_UNCOND_BRANCH)
-	{
-	  fix_crossing_unconditional_branches ();
-	  reg_scan (get_insns(), max_reg_num ());
-	}
-
-      add_reg_crossing_jump_notes ();
+  /* If the architecture does not have unconditional branches that
+     can span all of memory, convert crossing unconditional branches
+     into indirect jumps.  Since adding an indirect jump also adds
+     a new register usage, update the register usage information as
+     well.  */
+  
+  if (!HAS_LONG_UNCOND_BRANCH)
+    {
+      fix_crossing_unconditional_branches ();
+      reg_scan (get_insns(), max_reg_num ());
     }
+  
+  add_reg_crossing_jump_notes ();
 }
 
 /* Verify, in the basic block chain, that there is at most one switch
@@ -1942,7 +1929,8 @@ reorder_basic_blocks (unsigned int flags)
     dump_flow_info (dump_file);
 
   cfg_layout_finalize ();
-  verify_hot_cold_block_grouping ();
+  if (flag_reorder_blocks_and_partition)
+    verify_hot_cold_block_grouping ();
 
   timevar_pop (TV_REORDER_BLOCKS);
 }
@@ -1962,8 +1950,7 @@ insert_section_boundary_note (void)
   rtx new_note;
   int first_partition = 0;
   
-  if (flag_reorder_blocks_and_partition
-      && targetm.have_named_sections)
+  if (flag_reorder_blocks_and_partition)
     FOR_EACH_BB (bb)
     {
       if (!first_partition)

gcc/dbxout.c

@@ -939,10 +939,11 @@ dbxout_function_end (tree decl)
   if (flag_reorder_blocks_and_partition)
     {
       dbxout_begin_empty_stabs (N_FUN);
-      dbxout_stab_value_label_diff (hot_section_end_label, hot_section_label);
+      dbxout_stab_value_label_diff (cfun->hot_section_end_label, 
+				    cfun->hot_section_label);
       dbxout_begin_empty_stabs (N_FUN);
-      dbxout_stab_value_label_diff (cold_section_end_label, 
-				    unlikely_section_label);
+      dbxout_stab_value_label_diff (cfun->cold_section_end_label, 
+				    cfun->cold_section_label);
     }
   else
     {

gcc/dwarf2out.c

@@ -4122,6 +4122,9 @@ static int maybe_emit_file (int);
 #ifndef TEXT_SECTION_LABEL
 #define TEXT_SECTION_LABEL		"Ltext"
 #endif
+#ifndef COLD_TEXT_SECTION_LABEL
+#define COLD_TEXT_SECTION_LABEL         "Ltext_cold"
+#endif
 #ifndef DEBUG_LINE_SECTION_LABEL
 #define DEBUG_LINE_SECTION_LABEL	"Ldebug_line"
 #endif
@@ -4149,6 +4152,8 @@ static int maybe_emit_file (int);
 
 static char text_end_label[MAX_ARTIFICIAL_LABEL_BYTES];
 static char text_section_label[MAX_ARTIFICIAL_LABEL_BYTES];
+static char cold_text_section_label[MAX_ARTIFICIAL_LABEL_BYTES];
+static char cold_end_label[MAX_ARTIFICIAL_LABEL_BYTES]; 
 static char abbrev_section_label[MAX_ARTIFICIAL_LABEL_BYTES];
 static char debug_info_section_label[MAX_ARTIFICIAL_LABEL_BYTES];
 static char debug_line_section_label[MAX_ARTIFICIAL_LABEL_BYTES];
@@ -4159,6 +4164,9 @@ static char ranges_section_label[2 * MAX_ARTIFICIAL_LABEL_BYTES];
 #ifndef TEXT_END_LABEL
 #define TEXT_END_LABEL		"Letext"
 #endif
+#ifndef COLD_END_LABEL
+#define COLD_END_LABEL          "Letext_cold"
+#endif
 #ifndef BLOCK_BEGIN_LABEL
 #define BLOCK_BEGIN_LABEL	"LBB"
 #endif
@@ -6800,12 +6808,15 @@ dwarf2out_switch_text_section (void)
 {
   dw_fde_ref fde;
 
+  if (!cfun)
+    internal_error ("Attempt to switch text sections without any code.");
+
   fde = &fde_table[fde_table_in_use - 1];
   fde->dw_fde_switched_sections = true;
-  fde->dw_fde_hot_section_label = xstrdup (hot_section_label);
-  fde->dw_fde_hot_section_end_label = xstrdup (hot_section_end_label);
-  fde->dw_fde_unlikely_section_label = xstrdup (unlikely_section_label);
-  fde->dw_fde_unlikely_section_end_label = xstrdup (cold_section_end_label);
+  fde->dw_fde_hot_section_label = cfun->hot_section_label;
+  fde->dw_fde_hot_section_end_label = cfun->hot_section_end_label;
+  fde->dw_fde_unlikely_section_label = cfun->cold_section_label;
+  fde->dw_fde_unlikely_section_end_label = cfun->cold_section_end_label;
   separate_line_info_table_in_use++;
 }
 
@@ -7235,14 +7246,15 @@ output_aranges (void)
     }
 
   dw2_asm_output_addr (DWARF2_ADDR_SIZE, text_section_label, "Address");
-  if (last_text_section == in_unlikely_executed_text
-      || (last_text_section == in_named
-	  && last_text_section_name == unlikely_text_section_name))
-    dw2_asm_output_delta (DWARF2_ADDR_SIZE, text_end_label,
-			  unlikely_section_label, "Length");
-  else
-    dw2_asm_output_delta (DWARF2_ADDR_SIZE, text_end_label,
-			  text_section_label, "Length");
+  dw2_asm_output_delta (DWARF2_ADDR_SIZE, text_end_label,
+			text_section_label, "Length");
+  if (flag_reorder_blocks_and_partition)
+    {
+      dw2_asm_output_addr (DWARF2_ADDR_SIZE, cold_text_section_label, 
+			   "Address");
+      dw2_asm_output_delta (DWARF2_ADDR_SIZE, cold_end_label,
+			    cold_text_section_label, "Length");
+    }
 
   for (i = 0; i < arange_table_in_use; i++)
     {
@@ -7332,24 +7344,11 @@ output_ranges (void)
 	     base of the text section.  */
 	  if (separate_line_info_table_in_use == 0)
 	    {
-	      if (last_text_section == in_unlikely_executed_text
-		  || (last_text_section == in_named
-		      && last_text_section_name == unlikely_text_section_name))
-		{
-		  dw2_asm_output_delta (DWARF2_ADDR_SIZE, blabel,
-					unlikely_section_label,
-					fmt, i * 2 * DWARF2_ADDR_SIZE);
-		  dw2_asm_output_delta (DWARF2_ADDR_SIZE, elabel,
-					unlikely_section_label, NULL);
-		}
-	      else
-		{
-		  dw2_asm_output_delta (DWARF2_ADDR_SIZE, blabel,
-					text_section_label,
-					fmt, i * 2 * DWARF2_ADDR_SIZE);
-		  dw2_asm_output_delta (DWARF2_ADDR_SIZE, elabel,
-					text_section_label, NULL);
-		}
+	      dw2_asm_output_delta (DWARF2_ADDR_SIZE, blabel,
+				    text_section_label,
+				    fmt, i * 2 * DWARF2_ADDR_SIZE);
+	      dw2_asm_output_delta (DWARF2_ADDR_SIZE, elabel,
+				    text_section_label, NULL);
 	    }
 
 	  /* Otherwise, we add a DW_AT_entry_pc attribute to force the
@@ -7734,11 +7733,12 @@ output_line_info (void)
      a series of state machine operations.  */
   current_file = 1;
   current_line = 1;
-  
-  if (last_text_section == in_unlikely_executed_text
-      || (last_text_section == in_named
-	  && last_text_section_name == unlikely_text_section_name))
-    strcpy (prev_line_label, unlikely_section_label);
+
+  if (cfun
+      && (last_text_section == in_unlikely_executed_text
+	  || (last_text_section == in_named
+	      && last_text_section_name == cfun->unlikely_text_section_name)))
+    strcpy (prev_line_label, cfun->cold_section_label);
   else
     strcpy (prev_line_label, text_section_label);
   for (lt_index = 1; lt_index < line_info_table_in_use; ++lt_index)
@@ -10112,7 +10112,6 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
       dw_loc_list_ref list;
       rtx varloc;
 
-
       /* We need to figure out what section we should use as the base
 	 for the address ranges where a given location is valid.
 	 1. If this particular DECL has a section associated with it,
@@ -10134,10 +10133,12 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
 	  tree sectree = DECL_SECTION_NAME (current_function_decl);
 	  secname = TREE_STRING_POINTER (sectree);
 	}
-      else if (last_text_section == in_unlikely_executed_text
-	       || (last_text_section == in_named
-		   && last_text_section_name == unlikely_text_section_name))
-	secname = unlikely_section_label;
+      else if (cfun
+	       && (last_text_section == in_unlikely_executed_text
+		   || (last_text_section == in_named
+		       && last_text_section_name == 
+		       cfun->unlikely_text_section_name)))
+	secname = cfun->cold_section_label;
       else
 	secname = text_section_label;
 
@@ -13260,10 +13261,11 @@ dwarf2out_var_location (rtx loc_note)
   newloc->var_loc_note = loc_note;
   newloc->next = NULL;
 
-  if (last_text_section == in_unlikely_executed_text
-      || (last_text_section == in_named
-	  && last_text_section_name == unlikely_text_section_name))
-    newloc->section_label = unlikely_section_label;
+  if (cfun
+      && (last_text_section == in_unlikely_executed_text
+	  || (last_text_section == in_named
+	      && last_text_section_name == cfun->unlikely_text_section_name)))
+    newloc->section_label = cfun->cold_section_label;
   else
     newloc->section_label = text_section_label;
 
@@ -13501,6 +13503,9 @@ dwarf2out_init (const char *filename ATTRIBUTE_UNUSED)
   ASM_GENERATE_INTERNAL_LABEL (abbrev_section_label,
 			       DEBUG_ABBREV_SECTION_LABEL, 0);
   ASM_GENERATE_INTERNAL_LABEL (text_section_label, TEXT_SECTION_LABEL, 0);
+  ASM_GENERATE_INTERNAL_LABEL (cold_text_section_label, 
+			       COLD_TEXT_SECTION_LABEL, 0);
+  ASM_GENERATE_INTERNAL_LABEL (cold_end_label, COLD_END_LABEL, 0);
 
   ASM_GENERATE_INTERNAL_LABEL (debug_info_section_label,
 			       DEBUG_INFO_SECTION_LABEL, 0);
@@ -13525,6 +13530,11 @@ dwarf2out_init (const char *filename ATTRIBUTE_UNUSED)
 
   text_section ();
   ASM_OUTPUT_LABEL (asm_out_file, text_section_label);
+  if (flag_reorder_blocks_and_partition)
+    {
+      unlikely_text_section ();
+      ASM_OUTPUT_LABEL (asm_out_file, cold_text_section_label);
+    }
 }
 
 /* A helper function for dwarf2out_finish called through
@@ -13856,6 +13866,11 @@ dwarf2out_finish (const char *filename)
   /* Output a terminator label for the .text section.  */
   text_section ();
   targetm.asm_out.internal_label (asm_out_file, TEXT_END_LABEL, 0);
+  if (flag_reorder_blocks_and_partition)
+    {
+      unlikely_text_section ();
+      targetm.asm_out.internal_label (asm_out_file, COLD_END_LABEL, 0);
+    }
 
   /* Output the source line correspondence table.  We must do this
      even if there is no line information.  Otherwise, on an empty

gcc/function.h

@@ -352,6 +352,20 @@ struct function GTY(())
   /* The variables unexpanded so far.  */
   tree unexpanded_var_list;
 
+  /* Assembly labels for the hot and cold text sections, to
+     be used by debugger functions for determining the size of text
+     sections.  */
+
+  const char * hot_section_label;
+  const char * cold_section_label;
+  const char * hot_section_end_label;
+  const char * cold_section_end_label;
+
+  /* String to be used for name of cold text sections, via
+     targetm.asm_out.named_section.  */
+
+  const char *unlikely_text_section_name;
+
   /* Collected bit flags.  */
 
   /* Nonzero if function being compiled needs to be given an address

gcc/opts.c

@@ -678,6 +678,15 @@ decode_options (unsigned int argc, const char **argv)
       flag_reorder_blocks_and_partition = 0;
       flag_reorder_blocks = 1;
     }
+
+  if (flag_reorder_blocks_and_partition
+      && !targetm.have_named_sections)
+    {
+      inform 
+       ("-freorder-blocks-and-partition does not work on this architecture.");
+      flag_reorder_blocks_and_partition = 0;
+      flag_reorder_blocks = 1;
+    }
 }
 
 /* Handle target- and language-independent options.  Return zero to

gcc/output.h

@@ -453,11 +453,6 @@ enum in_section { no_section, in_text, in_unlikely_executed_text, in_data,
 #endif
 };
 
-extern char *unlikely_section_label;
-extern char *hot_section_label;
-extern char *hot_section_end_label;
-extern char *cold_section_end_label;
-extern char *unlikely_text_section_name;
 extern const char *last_text_section_name;
 extern enum in_section last_text_section;
 extern bool first_function_block_is_cold;

gcc/passes.c

@@ -328,7 +328,6 @@ rest_of_handle_final (void)
 
   timevar_push (TV_SYMOUT);
   (*debug_hooks->function_decl) (current_function_decl);
-
   timevar_pop (TV_SYMOUT);
 
   ggc_collect ();