[IEPM] Introduce inline entry point markersaoliva/SLI

Output DW_AT_entry_pc based on markers.

Introduce DW_AT_GNU_entry_view as a DWARF extension.

If views are enabled are we're not in strict compliance mode, output
DW_AT_GNU_entry_view if it might be nonzero.

This patch depends on SFN and LVU patchsets, and on the IEPM patch that
introduces the inline_entry debug hook.

for  include/ChangeLog

	* dwarf2.def (DW_AT_GNU_entry_view): New.

for  gcc/ChangeLog

	* cfgexpand.c (expand_gimple_basic_block): Handle inline entry
	markers.
	* dwarf2out.c (dwarf2_debug_hooks): Enable inline_entry hook.
	(BLOCK_INLINE_ENTRY_LABEL): New.
	(dwarf2out_var_location): Disregard inline entry markers.
	(inline_entry_data): New struct.
	(inline_entry_data_hasher): New hashtable type.
	(inline_entry_data_hasher::hash): New.
	(inline_entry_data_hasher::equal): New.
	(inline_entry_data_table): New variable.
	(add_high_low_attributes): Add DW_AT_entry_pc and
	DW_AT_GNU_entry_view attributes if a pending entry is found
	in inline_entry_data_table.  Add old entry_pc attribute only
	if debug nonbinding markers are disabled.
	(gen_inlined_subroutine_die): Set BLOCK_DIE if nonbinding
	markers are enabled.
	(block_within_block_p, dwarf2out_inline_entry): New.
	(dwarf2out_finish): Check that no entries remained in
	inline_entry_data_table.
	* final.c (reemit_insn_block_notes): Handle inline entry notes.
	(final_scan_insn, notice_source_line): Likewise.
	(rest_of_clean_state): Skip inline entry markers.
	* gimple-pretty-print.c (dump_gimple_debug): Handle inline entry
	markers.
	* gimple.c (gimple_build_debug_inline_entry): New.
	* gimple.h (enum gimple_debug_subcode): Add
	GIMPLE_DEBUG_INLINE_ENTRY.
	(gimple_build_debug_inline_entry): Declare.
	(gimple_debug_inline_entry_p): New.
	(gimple_debug_nonbind_marker_p): Adjust.
	* insn-notes.def (INLINE_ENTRY): New.
	* print-rtl.c (rtx_writer::print_rtx_operand_code_0): Handle
	inline entry marker notes.
	(print_insn): Likewise.
	* rtl.h	(NOTE_MARKER_P): Add INLINE_ENTRY support.
	(INSN_DEBUG_MARKER_KIND): Likewise.
	(GEN_RTX_DEBUG_MARKER_INLINE_ENTRY_PAT): New.
	* tree-inline.c	(expand_call_inline): Build and insert
	debug_inline_entry stmt.
	* tree-ssa-live.c (remove_unused_scope_block_p): Preserve
	inline entry blocks early, if nonbind markers are enabled.
	(dump_scope_block): Dump fragment info.
	* var-tracking.c (reemit_marker_as_note): Handle inline entry note.
	* doc/gimple.texi (gimple_debug_inline_entry_p): New.
	(gimple_build_debug_inline_entry): New.
	* doc/invoke.texi (gstatement-frontiers, gno-statement-frontiers):
	Enable/disable inline entry points too.
	* doc/rtl.texi (NOTE_INSN_INLINE_ENTRY): New.
	(DEBUG_INSN): Describe inline entry markers.

1 files changed, 22 insertions, 5 deletions

diff --git a/gcc/tree-ssa-live.c b/gcc/tree-ssa-live.c
index 8738fe21a6e..734d15df2c5 100644
--- a/gcc/tree-ssa-live.c
+++ b/gcc/tree-ssa-live.c
@@ -520,6 +520,11 @@ remove_unused_scope_block_p (tree scope, bool in_ctor_dtor_block)
    else if (!BLOCK_SUPERCONTEXT (scope)
             || TREE_CODE (BLOCK_SUPERCONTEXT (scope)) == FUNCTION_DECL)
      unused = false;
+   /* Preserve the block, it is referenced by at least the inline
+      entry point marker.  */
+   else if (debug_nonbind_markers_p
+	    && inlined_function_outer_scope_p (scope))
+     unused = false;
    /* Innermost blocks with no live variables nor statements can be always
       eliminated.  */
    else if (!nsubblocks)
@@ -548,11 +553,13 @@ remove_unused_scope_block_p (tree scope, bool in_ctor_dtor_block)
      }
    else if (BLOCK_VARS (scope) || BLOCK_NUM_NONLOCALIZED_VARS (scope))
      unused = false;
-   /* See if this block is important for representation of inlined function.
-      Inlined functions are always represented by block with
-      block_ultimate_origin being set to FUNCTION_DECL and DECL_SOURCE_LOCATION
-      set...  */
-   else if (inlined_function_outer_scope_p (scope))
+   /* See if this block is important for representation of inlined
+      function.  Inlined functions are always represented by block
+      with block_ultimate_origin being set to FUNCTION_DECL and
+      DECL_SOURCE_LOCATION set, unless they expand to nothing...  But
+      see above for the case of statement frontiers.  */
+   else if (!debug_nonbind_markers_p
+	    && inlined_function_outer_scope_p (scope))
      unused = false;
    else
    /* Verfify that only blocks with source location set
@@ -640,6 +647,16 @@ dump_scope_block (FILE *file, int indent, tree scope, dump_flags_t flags)
 	    fprintf (file, "#%i", BLOCK_NUMBER (origin));
 	}
     }
+  if (BLOCK_FRAGMENT_ORIGIN (scope))
+    fprintf (file, " Fragment of : #%i",
+	     BLOCK_NUMBER (BLOCK_FRAGMENT_ORIGIN (scope)));
+  else if (BLOCK_FRAGMENT_CHAIN (scope))
+    {
+      fprintf (file, " Fragment chain :");
+      for (t = BLOCK_FRAGMENT_CHAIN (scope); t ;
+	   t = BLOCK_FRAGMENT_CHAIN (t))
+	fprintf (file, " #%i", BLOCK_NUMBER (t));
+    }
   fprintf (file, " \n");
   for (var = BLOCK_VARS (scope); var; var = DECL_CHAIN (var))
     {