gimple const-correctness fixes

This patch converts various "gimple *" to "const gimple *" and similar
fixes for gimple subclasses, adding is_a_helper for gimple subclasses
to support the const form of as_a, and adding a few "const" overloads
of accessors.

This is enough to make pp_gimple_stmt_1's stmt const.

gcc/ChangeLog:
	* gimple-predict.h (gimple_predict_predictor): Make "gs" param
	const.
	(gimple_predict_outcome): Likewise.
	* gimple-pretty-print.c (do_niy): Likewise.
	(dump_unary_rhs): Likewise.
	(dump_binary_rhs): Likewise.
	(dump_ternary_rhs): Likewise.
	(dump_gimple_assign): Likewise.
	(dump_gimple_return): Likewise.
	(dump_gimple_call_args): Likewise.
	(pp_points_to_solution): Make "pt" param const.
	(dump_gimple_call): Make "gs" param const.
	(dump_gimple_switch): Likewise.
	(dump_gimple_cond): Likewise.
	(dump_gimple_label): Likewise.
	(dump_gimple_goto): Likewise.
	(dump_gimple_bind): Likewise.
	(dump_gimple_try): Likewise.
	(dump_gimple_catch): Likewise.
	(dump_gimple_eh_filter): Likewise.
	(dump_gimple_eh_must_not_throw): Likewise.
	(dump_gimple_eh_else): Likewise.
	(dump_gimple_resx): Likewise.
	(dump_gimple_eh_dispatch): Likewise.
	(dump_gimple_debug): Likewise.
	(dump_gimple_omp_for): Likewise.
	(dump_gimple_omp_continue): Likewise.
	(dump_gimple_omp_single): Likewise.
	(dump_gimple_omp_taskgroup): Likewise.
	(dump_gimple_omp_target): Likewise.
	(dump_gimple_omp_teams): Likewise.
	(dump_gimple_omp_sections): Likewise.
	(dump_gimple_omp_block): Likewise.
	(dump_gimple_omp_critical): Likewise.
	(dump_gimple_omp_ordered): Likewise.
	(dump_gimple_omp_scan): Likewise.
	(dump_gimple_omp_return): Likewise.
	(dump_gimple_transaction): Likewise.
	(dump_gimple_asm): Likewise.
	(dump_gimple_phi): Make "phi" param const.
	(dump_gimple_omp_parallel): Make "gs" param const.
	(dump_gimple_omp_task): Likewise.
	(dump_gimple_omp_atomic_load): Likewise.
	(dump_gimple_omp_atomic_store): Likewise.
	(dump_gimple_mem_ops): Likewise.
	(pp_gimple_stmt_1): Likewise.  Add "const" to the various as_a <>
	casts throughout.
	* gimple-pretty-print.h (gimple_stmt_1): Make gimple * param const.
	* gimple.h (is_a_helper <const gdebug *>::test): New.
	(is_a_helper <const ggoto *>::test): New.
	(is_a_helper <const glabel *>::test): New.
	(is_a_helper <const geh_else *>::test): New.
	(is_a_helper <const geh_mnt *>::test): New.
	(is_a_helper <const gswitch *>::test): New.
	(is_a_helper <const gtry *>::test): New.
	(is_a_helper <const greturn *>::test): New.
	(gimple_call_tail_p): Make param const.
	(gimple_call_return_slot_opt_p): Likewise.
	(gimple_call_va_arg_pack_p): Likewise.
	(gimple_call_use_set): Add const overload.
	(gimple_call_clobber_set): Likewise.
	(gimple_has_lhs): Make param const.
	(gimple_bind_body): Likewise.
	(gimple_catch_handler): Likewise.
	(gimple_eh_filter_failure): Likewise.
	(gimple_eh_must_not_throw_fndecl): Likewise.
	(gimple_eh_else_n_body): Likewise.
	(gimple_eh_else_e_body): Likewise.
	(gimple_try_eval): Likewise.
	(gimple_try_cleanup): Likewise.
	(gimple_phi_arg): Add const overload.
	(gimple_phi_arg_def): Make param const.
	(gimple_phi_arg_edge): Likewise.
	(gimple_phi_arg_location): Likewise.
	(gimple_phi_arg_has_location): Likewise.
	(gimple_debug_bind_get_var): Likewise.
	(gimple_debug_bind_get_value): Likewise.
	(gimple_debug_source_bind_get_var): Likewise.
	(gimple_debug_source_bind_get_value): Likewise.
	(gimple_omp_body): Likewise.
	(gimple_omp_for_collapse): Likewise.
	(gimple_omp_for_pre_body): Likewise.
	(gimple_transaction_body): Likewise.
	* tree-eh.c (lookup_stmt_eh_lp_fn): Make param "t" const.
	(lookup_stmt_eh_lp): Likewise.
	* tree-eh.h (lookup_stmt_eh_lp_fn): Make param const.
	(lookup_stmt_eh_lp): Likewise.
	* tree-ssa-alias.h (pt_solution_empty_p): Make param const.
	* tree-ssa-structalias.c (pt_solution_empty_p): Likewise.

From-SVN: r279581

9 files changed, 305 insertions, 123 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 308774d..4892f03 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,95 @@
+2019-12-19  David Malcolm  <dmalcolm@redhat.com>
+
+	* gimple-predict.h (gimple_predict_predictor): Make "gs" param
+	const.
+	(gimple_predict_outcome): Likewise.
+	* gimple-pretty-print.c (do_niy): Likewise.
+	(dump_unary_rhs): Likewise.
+	(dump_binary_rhs): Likewise.
+	(dump_ternary_rhs): Likewise.
+	(dump_gimple_assign): Likewise.
+	(dump_gimple_return): Likewise.
+	(dump_gimple_call_args): Likewise.
+	(pp_points_to_solution): Make "pt" param const.
+	(dump_gimple_call): Make "gs" param const.
+	(dump_gimple_switch): Likewise.
+	(dump_gimple_cond): Likewise.
+	(dump_gimple_label): Likewise.
+	(dump_gimple_goto): Likewise.
+	(dump_gimple_bind): Likewise.
+	(dump_gimple_try): Likewise.
+	(dump_gimple_catch): Likewise.
+	(dump_gimple_eh_filter): Likewise.
+	(dump_gimple_eh_must_not_throw): Likewise.
+	(dump_gimple_eh_else): Likewise.
+	(dump_gimple_resx): Likewise.
+	(dump_gimple_eh_dispatch): Likewise.
+	(dump_gimple_debug): Likewise.
+	(dump_gimple_omp_for): Likewise.
+	(dump_gimple_omp_continue): Likewise.
+	(dump_gimple_omp_single): Likewise.
+	(dump_gimple_omp_taskgroup): Likewise.
+	(dump_gimple_omp_target): Likewise.
+	(dump_gimple_omp_teams): Likewise.
+	(dump_gimple_omp_sections): Likewise.
+	(dump_gimple_omp_block): Likewise.
+	(dump_gimple_omp_critical): Likewise.
+	(dump_gimple_omp_ordered): Likewise.
+	(dump_gimple_omp_scan): Likewise.
+	(dump_gimple_omp_return): Likewise.
+	(dump_gimple_transaction): Likewise.
+	(dump_gimple_asm): Likewise.
+	(dump_gimple_phi): Make "phi" param const.
+	(dump_gimple_omp_parallel): Make "gs" param const.
+	(dump_gimple_omp_task): Likewise.
+	(dump_gimple_omp_atomic_load): Likewise.
+	(dump_gimple_omp_atomic_store): Likewise.
+	(dump_gimple_mem_ops): Likewise.
+	(pp_gimple_stmt_1): Likewise.  Add "const" to the various as_a <>
+	casts throughout.
+	* gimple-pretty-print.h (gimple_stmt_1): Make gimple * param const.
+	* gimple.h (is_a_helper <const gdebug *>::test): New.
+	(is_a_helper <const ggoto *>::test): New.
+	(is_a_helper <const glabel *>::test): New.
+	(is_a_helper <const geh_else *>::test): New.
+	(is_a_helper <const geh_mnt *>::test): New.
+	(is_a_helper <const gswitch *>::test): New.
+	(is_a_helper <const gtry *>::test): New.
+	(is_a_helper <const greturn *>::test): New.
+	(gimple_call_tail_p): Make param const.
+	(gimple_call_return_slot_opt_p): Likewise.
+	(gimple_call_va_arg_pack_p): Likewise.
+	(gimple_call_use_set): Add const overload.
+	(gimple_call_clobber_set): Likewise.
+	(gimple_has_lhs): Make param const.
+	(gimple_bind_body): Likewise.
+	(gimple_catch_handler): Likewise.
+	(gimple_eh_filter_failure): Likewise.
+	(gimple_eh_must_not_throw_fndecl): Likewise.
+	(gimple_eh_else_n_body): Likewise.
+	(gimple_eh_else_e_body): Likewise.
+	(gimple_try_eval): Likewise.
+	(gimple_try_cleanup): Likewise.
+	(gimple_phi_arg): Add const overload.
+	(gimple_phi_arg_def): Make param const.
+	(gimple_phi_arg_edge): Likewise.
+	(gimple_phi_arg_location): Likewise.
+	(gimple_phi_arg_has_location): Likewise.
+	(gimple_debug_bind_get_var): Likewise.
+	(gimple_debug_bind_get_value): Likewise.
+	(gimple_debug_source_bind_get_var): Likewise.
+	(gimple_debug_source_bind_get_value): Likewise.
+	(gimple_omp_body): Likewise.
+	(gimple_omp_for_collapse): Likewise.
+	(gimple_omp_for_pre_body): Likewise.
+	(gimple_transaction_body): Likewise.
+	* tree-eh.c (lookup_stmt_eh_lp_fn): Make param "t" const.
+	(lookup_stmt_eh_lp): Likewise.
+	* tree-eh.h (lookup_stmt_eh_lp_fn): Make param const.
+	(lookup_stmt_eh_lp): Likewise.
+	* tree-ssa-alias.h (pt_solution_empty_p): Make param const.
+	* tree-ssa-structalias.c (pt_solution_empty_p): Likewise.
+
 2019-12-19  Richard Sandiford  <richard.sandiford@arm.com>
 
 	* config/aarch64/aarch64.c (aarch64_simd_valid_immediate): When
diff --git a/gcc/gimple-predict.h b/gcc/gimple-predict.h
index 761098b..d976317 100644
--- a/gcc/gimple-predict.h
+++ b/gcc/gimple-predict.h
@@ -26,7 +26,7 @@ along with GCC; see the file COPYING3.  If not see
 /* Return the predictor of GIMPLE_PREDICT statement GS.  */
 
 static inline enum br_predictor
-gimple_predict_predictor (gimple *gs)
+gimple_predict_predictor (const gimple *gs)
 {
   GIMPLE_CHECK (gs, GIMPLE_PREDICT);
   return (enum br_predictor) (gs->subcode & ~GF_PREDICT_TAKEN);
@@ -47,7 +47,7 @@ gimple_predict_set_predictor (gimple *gs, enum br_predictor predictor)
 /* Return the outcome of GIMPLE_PREDICT statement GS.  */
 
 static inline enum prediction
-gimple_predict_outcome (gimple *gs)
+gimple_predict_outcome (const gimple *gs)
 {
   GIMPLE_CHECK (gs, GIMPLE_PREDICT);
   return (gs->subcode & GF_PREDICT_TAKEN) ? TAKEN : NOT_TAKEN;
diff --git a/gcc/gimple-pretty-print.c b/gcc/gimple-pretty-print.c
index f59cc2a..9ec435f 100644
--- a/gcc/gimple-pretty-print.c
+++ b/gcc/gimple-pretty-print.c
@@ -59,7 +59,7 @@ along with GCC; see the file COPYING3.  If not see
    gimple statement GS.  */
 
 static void
-do_niy (pretty_printer *buffer, gimple *gs)
+do_niy (pretty_printer *buffer, const gimple *gs)
 {
   pp_printf (buffer, "<<< Unknown GIMPLE statement: %s >>>\n",
 	     gimple_code_name[(int) gimple_code (gs)]);
@@ -327,7 +327,7 @@ dump_gimple_fmt (pretty_printer *buffer, int spc, dump_flags_t flags,
    assignment GS.  BUFFER, SPC and FLAGS are as in pp_gimple_stmt_1.  */
 
 static void
-dump_unary_rhs (pretty_printer *buffer, gassign *gs, int spc,
+dump_unary_rhs (pretty_printer *buffer, const gassign *gs, int spc,
 		dump_flags_t flags)
 {
   enum tree_code rhs_code = gimple_assign_rhs_code (gs);
@@ -423,7 +423,7 @@ dump_unary_rhs (pretty_printer *buffer, gassign *gs, int spc,
    assignment GS.  BUFFER, SPC and FLAGS are as in pp_gimple_stmt_1.  */
 
 static void
-dump_binary_rhs (pretty_printer *buffer, gassign *gs, int spc,
+dump_binary_rhs (pretty_printer *buffer, const gassign *gs, int spc,
 		 dump_flags_t flags)
 {
   const char *p;
@@ -495,7 +495,7 @@ dump_binary_rhs (pretty_printer *buffer, gassign *gs, int spc,
    assignment GS.  BUFFER, SPC and FLAGS are as in pp_gimple_stmt_1.  */
 
 static void
-dump_ternary_rhs (pretty_printer *buffer, gassign *gs, int spc,
+dump_ternary_rhs (pretty_printer *buffer, const gassign *gs, int spc,
 		  dump_flags_t flags)
 {
   const char *p;
@@ -625,7 +625,7 @@ dump_ternary_rhs (pretty_printer *buffer, gassign *gs, int spc,
    pp_gimple_stmt_1.  */
 
 static void
-dump_gimple_assign (pretty_printer *buffer, gassign *gs, int spc,
+dump_gimple_assign (pretty_printer *buffer, const gassign *gs, int spc,
 		    dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -687,7 +687,7 @@ dump_gimple_assign (pretty_printer *buffer, gassign *gs, int spc,
    pp_gimple_stmt_1.  */
 
 static void
-dump_gimple_return (pretty_printer *buffer, greturn *gs, int spc,
+dump_gimple_return (pretty_printer *buffer, const greturn *gs, int spc,
 		    dump_flags_t flags)
 {
   tree t;
@@ -712,7 +712,8 @@ dump_gimple_return (pretty_printer *buffer, greturn *gs, int spc,
    dump_gimple_call.  */
 
 static void
-dump_gimple_call_args (pretty_printer *buffer, gcall *gs, dump_flags_t flags)
+dump_gimple_call_args (pretty_printer *buffer, const gcall *gs,
+		       dump_flags_t flags)
 {
   size_t i = 0;
 
@@ -795,7 +796,7 @@ dump_gimple_call_args (pretty_printer *buffer, gcall *gs, dump_flags_t flags)
 /* Dump the points-to solution *PT to BUFFER.  */
 
 static void
-pp_points_to_solution (pretty_printer *buffer, struct pt_solution *pt)
+pp_points_to_solution (pretty_printer *buffer, const pt_solution *pt)
 {
   if (pt->anything)
     {
@@ -868,7 +869,7 @@ pp_points_to_solution (pretty_printer *buffer, struct pt_solution *pt)
    pp_gimple_stmt_1.  */
 
 static void
-dump_gimple_call (pretty_printer *buffer, gcall *gs, int spc,
+dump_gimple_call (pretty_printer *buffer, const gcall *gs, int spc,
 		  dump_flags_t flags)
 {
   tree lhs = gimple_call_lhs (gs);
@@ -876,7 +877,7 @@ dump_gimple_call (pretty_printer *buffer, gcall *gs, int spc,
 
   if (flags & TDF_ALIAS)
     {
-      struct pt_solution *pt;
+      const pt_solution *pt;
       pt = gimple_call_use_set (gs);
       if (!pt_solution_empty_p (pt))
 	{
@@ -1006,7 +1007,7 @@ dump_gimple_call (pretty_printer *buffer, gcall *gs, int spc,
    pp_gimple_stmt_1.  */
 
 static void
-dump_gimple_switch (pretty_printer *buffer, gswitch *gs, int spc,
+dump_gimple_switch (pretty_printer *buffer, const gswitch *gs, int spc,
 		    dump_flags_t flags)
 {
   unsigned int i;
@@ -1064,7 +1065,7 @@ dump_gimple_switch (pretty_printer *buffer, gswitch *gs, int spc,
    pp_gimple_stmt_1.  */
 
 static void
-dump_gimple_cond (pretty_printer *buffer, gcond *gs, int spc,
+dump_gimple_cond (pretty_printer *buffer, const gcond *gs, int spc,
 		  dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1131,7 +1132,7 @@ dump_gimple_cond (pretty_printer *buffer, gcond *gs, int spc,
    TDF_* in dumpfils.h).  */
 
 static void
-dump_gimple_label (pretty_printer *buffer, glabel *gs, int spc,
+dump_gimple_label (pretty_printer *buffer, const glabel *gs, int spc,
 		   dump_flags_t flags)
 {
   tree label = gimple_label_label (gs);
@@ -1155,7 +1156,7 @@ dump_gimple_label (pretty_printer *buffer, glabel *gs, int spc,
    TDF_* in dumpfile.h).  */
 
 static void
-dump_gimple_goto (pretty_printer *buffer, ggoto *gs, int spc,
+dump_gimple_goto (pretty_printer *buffer, const ggoto *gs, int spc,
 		  dump_flags_t flags)
 {
   tree label = gimple_goto_dest (gs);
@@ -1171,7 +1172,7 @@ dump_gimple_goto (pretty_printer *buffer, ggoto *gs, int spc,
    TDF_* in dumpfile.h).  */
 
 static void
-dump_gimple_bind (pretty_printer *buffer, gbind *gs, int spc,
+dump_gimple_bind (pretty_printer *buffer, const gbind *gs, int spc,
 		  dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1205,7 +1206,7 @@ dump_gimple_bind (pretty_printer *buffer, gbind *gs, int spc,
    dumpfile.h).  */
 
 static void
-dump_gimple_try (pretty_printer *buffer, gtry *gs, int spc,
+dump_gimple_try (pretty_printer *buffer, const gtry *gs, int spc,
 		 dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1280,7 +1281,7 @@ dump_gimple_try (pretty_printer *buffer, gtry *gs, int spc,
    dumpfile.h).  */
 
 static void
-dump_gimple_catch (pretty_printer *buffer, gcatch *gs, int spc,
+dump_gimple_catch (pretty_printer *buffer, const gcatch *gs, int spc,
 		   dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1297,7 +1298,7 @@ dump_gimple_catch (pretty_printer *buffer, gcatch *gs, int spc,
    dumpfile.h).  */
 
 static void
-dump_gimple_eh_filter (pretty_printer *buffer, geh_filter *gs, int spc,
+dump_gimple_eh_filter (pretty_printer *buffer, const geh_filter *gs, int spc,
 		       dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1315,7 +1316,7 @@ dump_gimple_eh_filter (pretty_printer *buffer, geh_filter *gs, int spc,
 
 static void
 dump_gimple_eh_must_not_throw (pretty_printer *buffer,
-			       geh_mnt *gs, int spc, dump_flags_t flags)
+			       const geh_mnt *gs, int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
     dump_gimple_fmt (buffer, spc, flags, "%G <%T>", gs,
@@ -1331,7 +1332,7 @@ dump_gimple_eh_must_not_throw (pretty_printer *buffer,
    dumpfile.h).  */
 
 static void
-dump_gimple_eh_else (pretty_printer *buffer, geh_else *gs, int spc,
+dump_gimple_eh_else (pretty_printer *buffer, const geh_else *gs, int spc,
 		     dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1350,7 +1351,7 @@ dump_gimple_eh_else (pretty_printer *buffer, geh_else *gs, int spc,
    dumpfile.h).  */
 
 static void
-dump_gimple_resx (pretty_printer *buffer, gresx *gs, int spc,
+dump_gimple_resx (pretty_printer *buffer, const gresx *gs, int spc,
 		  dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1363,8 +1364,8 @@ dump_gimple_resx (pretty_printer *buffer, gresx *gs, int spc,
 /* Dump a GIMPLE_EH_DISPATCH tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_eh_dispatch (pretty_printer *buffer, geh_dispatch *gs, int spc,
-			 dump_flags_t flags)
+dump_gimple_eh_dispatch (pretty_printer *buffer, const geh_dispatch *gs,
+			 int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
     dump_gimple_fmt (buffer, spc, flags, "%G <%d>", gs,
@@ -1379,7 +1380,7 @@ dump_gimple_eh_dispatch (pretty_printer *buffer, geh_dispatch *gs, int spc,
    in dumpfile.h).  */
 
 static void
-dump_gimple_debug (pretty_printer *buffer, gdebug *gs, int spc,
+dump_gimple_debug (pretty_printer *buffer, const gdebug *gs, int spc,
 		   dump_flags_t flags)
 {
   switch (gs->subcode)
@@ -1433,7 +1434,7 @@ dump_gimple_debug (pretty_printer *buffer, gdebug *gs, int spc,
 
 /* Dump a GIMPLE_OMP_FOR tuple on the pretty_printer BUFFER.  */
 static void
-dump_gimple_omp_for (pretty_printer *buffer, gomp_for *gs, int spc,
+dump_gimple_omp_for (pretty_printer *buffer, const gomp_for *gs, int spc,
 		     dump_flags_t flags)
 {
   size_t i;
@@ -1566,7 +1567,7 @@ dump_gimple_omp_for (pretty_printer *buffer, gomp_for *gs, int spc,
 /* Dump a GIMPLE_OMP_CONTINUE tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_continue (pretty_printer *buffer, gomp_continue *gs,
+dump_gimple_omp_continue (pretty_printer *buffer, const gomp_continue *gs,
 			  int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1591,7 +1592,7 @@ dump_gimple_omp_continue (pretty_printer *buffer, gomp_continue *gs,
 /* Dump a GIMPLE_OMP_SINGLE tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_single (pretty_printer *buffer, gomp_single *gs,
+dump_gimple_omp_single (pretty_printer *buffer, const gomp_single *gs,
 			int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1620,7 +1621,7 @@ dump_gimple_omp_single (pretty_printer *buffer, gomp_single *gs,
 /* Dump a GIMPLE_OMP_TASKGROUP tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_taskgroup (pretty_printer *buffer, gimple *gs,
+dump_gimple_omp_taskgroup (pretty_printer *buffer, const gimple *gs,
 			   int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1649,7 +1650,7 @@ dump_gimple_omp_taskgroup (pretty_printer *buffer, gimple *gs,
 /* Dump a GIMPLE_OMP_TARGET tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_target (pretty_printer *buffer, gomp_target *gs,
+dump_gimple_omp_target (pretty_printer *buffer, const gomp_target *gs,
 			int spc, dump_flags_t flags)
 {
   const char *kind;
@@ -1745,7 +1746,7 @@ dump_gimple_omp_target (pretty_printer *buffer, gomp_target *gs,
 /* Dump a GIMPLE_OMP_TEAMS tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_teams (pretty_printer *buffer, gomp_teams *gs, int spc,
+dump_gimple_omp_teams (pretty_printer *buffer, const gomp_teams *gs, int spc,
 		       dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1774,7 +1775,7 @@ dump_gimple_omp_teams (pretty_printer *buffer, gomp_teams *gs, int spc,
 /* Dump a GIMPLE_OMP_SECTIONS tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_sections (pretty_printer *buffer, gomp_sections *gs,
+dump_gimple_omp_sections (pretty_printer *buffer, const gomp_sections *gs,
 			  int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1811,7 +1812,7 @@ dump_gimple_omp_sections (pretty_printer *buffer, gomp_sections *gs,
    pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_block (pretty_printer *buffer, gimple *gs, int spc,
+dump_gimple_omp_block (pretty_printer *buffer, const gimple *gs, int spc,
 		       dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1848,7 +1849,7 @@ dump_gimple_omp_block (pretty_printer *buffer, gimple *gs, int spc,
 /* Dump a GIMPLE_OMP_CRITICAL tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_critical (pretty_printer *buffer, gomp_critical *gs,
+dump_gimple_omp_critical (pretty_printer *buffer, const gomp_critical *gs,
 			  int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1880,7 +1881,7 @@ dump_gimple_omp_critical (pretty_printer *buffer, gomp_critical *gs,
 /* Dump a GIMPLE_OMP_ORDERED tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_ordered (pretty_printer *buffer, gomp_ordered *gs,
+dump_gimple_omp_ordered (pretty_printer *buffer, const gomp_ordered *gs,
 			 int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1905,7 +1906,7 @@ dump_gimple_omp_ordered (pretty_printer *buffer, gomp_ordered *gs,
 /* Dump a GIMPLE_OMP_SCAN tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_scan (pretty_printer *buffer, gomp_scan *gs,
+dump_gimple_omp_scan (pretty_printer *buffer, const gomp_scan *gs,
 		      int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1933,7 +1934,7 @@ dump_gimple_omp_scan (pretty_printer *buffer, gomp_scan *gs,
 /* Dump a GIMPLE_OMP_RETURN tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_omp_return (pretty_printer *buffer, gimple *gs, int spc,
+dump_gimple_omp_return (pretty_printer *buffer, const gimple *gs, int spc,
 			dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -1964,7 +1965,7 @@ dump_gimple_omp_return (pretty_printer *buffer, gimple *gs, int spc,
 /* Dump a GIMPLE_TRANSACTION tuple on the pretty_printer BUFFER.  */
 
 static void
-dump_gimple_transaction (pretty_printer *buffer, gtransaction *gs,
+dump_gimple_transaction (pretty_printer *buffer, const gtransaction *gs,
 			 int spc, dump_flags_t flags)
 {
   unsigned subcode = gimple_transaction_subcode (gs);
@@ -2066,7 +2067,8 @@ dump_gimple_transaction (pretty_printer *buffer, gtransaction *gs,
    dumpfile.h).  */
 
 static void
-dump_gimple_asm (pretty_printer *buffer, gasm *gs, int spc, dump_flags_t flags)
+dump_gimple_asm (pretty_printer *buffer, const gasm *gs, int spc,
+		 dump_flags_t flags)
 {
   unsigned int i, n, f, fields;
 
@@ -2285,7 +2287,7 @@ dump_ssaname_info_to_file (FILE *file, tree node, int spc)
    pretty printer.  If COMMENT is true, print this after #.  */
 
 static void
-dump_gimple_phi (pretty_printer *buffer, gphi *phi, int spc, bool comment,
+dump_gimple_phi (pretty_printer *buffer, const gphi *phi, int spc, bool comment,
 		 dump_flags_t flags)
 {
   size_t i;
@@ -2342,7 +2344,7 @@ dump_gimple_phi (pretty_printer *buffer, gphi *phi, int spc, bool comment,
    dumpfile.h).  */
 
 static void
-dump_gimple_omp_parallel (pretty_printer *buffer, gomp_parallel *gs,
+dump_gimple_omp_parallel (pretty_printer *buffer, const gomp_parallel *gs,
 			  int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -2396,7 +2398,7 @@ dump_gimple_omp_parallel (pretty_printer *buffer, gomp_parallel *gs,
    dumpfile.h).  */
 
 static void
-dump_gimple_omp_task (pretty_printer *buffer, gomp_task *gs, int spc,
+dump_gimple_omp_task (pretty_printer *buffer, const gomp_task *gs, int spc,
 		      dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -2458,7 +2460,7 @@ dump_gimple_omp_task (pretty_printer *buffer, gomp_task *gs, int spc,
    in dumpfile.h).  */
 
 static void
-dump_gimple_omp_atomic_load (pretty_printer *buffer, gomp_atomic_load *gs,
+dump_gimple_omp_atomic_load (pretty_printer *buffer, const gomp_atomic_load *gs,
 			     int spc, dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -2492,7 +2494,7 @@ dump_gimple_omp_atomic_load (pretty_printer *buffer, gomp_atomic_load *gs,
 
 static void
 dump_gimple_omp_atomic_store (pretty_printer *buffer,
-			      gomp_atomic_store *gs, int spc,
+			      const gomp_atomic_store *gs, int spc,
 			      dump_flags_t flags)
 {
   if (flags & TDF_RAW)
@@ -2520,7 +2522,7 @@ dump_gimple_omp_atomic_store (pretty_printer *buffer,
    FLAGS are as in pp_gimple_stmt_1.  */
 
 static void
-dump_gimple_mem_ops (pretty_printer *buffer, gimple *gs, int spc,
+dump_gimple_mem_ops (pretty_printer *buffer, const gimple *gs, int spc,
 		     dump_flags_t flags)
 {
   tree vdef = gimple_vdef (gs);
@@ -2551,14 +2553,14 @@ dump_gimple_mem_ops (pretty_printer *buffer, gimple *gs, int spc,
    pp_flush on BUFFER to finalize the pretty printer.  */
 
 void
-pp_gimple_stmt_1 (pretty_printer *buffer, gimple *gs, int spc,
+pp_gimple_stmt_1 (pretty_printer *buffer, const gimple *gs, int spc,
 		  dump_flags_t flags)
 {
   if (!gs)
     return;
 
   if (flags & TDF_STMTADDR)
-    pp_printf (buffer, "<&%p> ", (void *) gs);
+    pp_printf (buffer, "<&%p> ", (const void *) gs);
 
   if ((flags & TDF_LINENO) && gimple_has_location (gs))
     dump_location (buffer, gimple_location (gs));
@@ -2583,31 +2585,31 @@ pp_gimple_stmt_1 (pretty_printer *buffer, gimple *gs, int spc,
   switch (gimple_code (gs))
     {
     case GIMPLE_ASM:
-      dump_gimple_asm (buffer, as_a <gasm *> (gs), spc, flags);
+      dump_gimple_asm (buffer, as_a <const gasm *> (gs), spc, flags);
       break;
 
     case GIMPLE_ASSIGN:
-      dump_gimple_assign (buffer, as_a <gassign *> (gs), spc, flags);
+      dump_gimple_assign (buffer, as_a <const gassign *> (gs), spc, flags);
       break;
 
     case GIMPLE_BIND:
-      dump_gimple_bind (buffer, as_a <gbind *> (gs), spc, flags);
+      dump_gimple_bind (buffer, as_a <const gbind *> (gs), spc, flags);
       break;
 
     case GIMPLE_CALL:
-      dump_gimple_call (buffer, as_a <gcall *> (gs), spc, flags);
+      dump_gimple_call (buffer, as_a <const gcall *> (gs), spc, flags);
       break;
 
     case GIMPLE_COND:
-      dump_gimple_cond (buffer, as_a <gcond *> (gs), spc, flags);
+      dump_gimple_cond (buffer, as_a <const gcond *> (gs), spc, flags);
       break;
 
     case GIMPLE_LABEL:
-      dump_gimple_label (buffer, as_a <glabel *> (gs), spc, flags);
+      dump_gimple_label (buffer, as_a <const glabel *> (gs), spc, flags);
       break;
 
     case GIMPLE_GOTO:
-      dump_gimple_goto (buffer, as_a <ggoto *> (gs), spc, flags);
+      dump_gimple_goto (buffer, as_a <const ggoto *> (gs), spc, flags);
       break;
 
     case GIMPLE_NOP:
@@ -2615,62 +2617,62 @@ pp_gimple_stmt_1 (pretty_printer *buffer, gimple *gs, int spc,
       break;
 
     case GIMPLE_RETURN:
-      dump_gimple_return (buffer, as_a <greturn *> (gs), spc, flags);
+      dump_gimple_return (buffer, as_a <const greturn *> (gs), spc, flags);
       break;
 
     case GIMPLE_SWITCH:
-      dump_gimple_switch (buffer, as_a <gswitch *> (gs), spc, flags);
+      dump_gimple_switch (buffer, as_a <const gswitch *> (gs), spc, flags);
       break;
 
     case GIMPLE_TRY:
-      dump_gimple_try (buffer, as_a <gtry *> (gs), spc, flags);
+      dump_gimple_try (buffer, as_a <const gtry *> (gs), spc, flags);
       break;
 
     case GIMPLE_PHI:
-      dump_gimple_phi (buffer, as_a <gphi *> (gs), spc, false, flags);
+      dump_gimple_phi (buffer, as_a <const gphi *> (gs), spc, false, flags);
       break;
 
     case GIMPLE_OMP_PARALLEL:
-      dump_gimple_omp_parallel (buffer, as_a <gomp_parallel *> (gs), spc,
+      dump_gimple_omp_parallel (buffer, as_a <const gomp_parallel *> (gs), spc,
 				flags);
       break;
 
     case GIMPLE_OMP_TASK:
-      dump_gimple_omp_task (buffer, as_a <gomp_task *> (gs), spc, flags);
+      dump_gimple_omp_task (buffer, as_a <const gomp_task *> (gs), spc, flags);
       break;
 
     case GIMPLE_OMP_ATOMIC_LOAD:
-      dump_gimple_omp_atomic_load (buffer, as_a <gomp_atomic_load *> (gs),
+      dump_gimple_omp_atomic_load (buffer, as_a <const gomp_atomic_load *> (gs),
 				   spc, flags);
       break;
 
     case GIMPLE_OMP_ATOMIC_STORE:
       dump_gimple_omp_atomic_store (buffer,
-				    as_a <gomp_atomic_store *> (gs),
+				    as_a <const gomp_atomic_store *> (gs),
 				    spc, flags);
       break;
 
     case GIMPLE_OMP_FOR:
-      dump_gimple_omp_for (buffer, as_a <gomp_for *> (gs), spc, flags);
+      dump_gimple_omp_for (buffer, as_a <const gomp_for *> (gs), spc, flags);
       break;
 
     case GIMPLE_OMP_CONTINUE:
-      dump_gimple_omp_continue (buffer, as_a <gomp_continue *> (gs), spc,
+      dump_gimple_omp_continue (buffer, as_a <const gomp_continue *> (gs), spc,
 				flags);
       break;
 
     case GIMPLE_OMP_SINGLE:
-      dump_gimple_omp_single (buffer, as_a <gomp_single *> (gs), spc,
+      dump_gimple_omp_single (buffer, as_a <const gomp_single *> (gs), spc,
 			      flags);
       break;
 
     case GIMPLE_OMP_TARGET:
-      dump_gimple_omp_target (buffer, as_a <gomp_target *> (gs), spc,
+      dump_gimple_omp_target (buffer, as_a <const gomp_target *> (gs), spc,
 			      flags);
       break;
 
     case GIMPLE_OMP_TEAMS:
-      dump_gimple_omp_teams (buffer, as_a <gomp_teams *> (gs), spc,
+      dump_gimple_omp_teams (buffer, as_a <const gomp_teams *> (gs), spc,
 			     flags);
       break;
 
@@ -2679,7 +2681,7 @@ pp_gimple_stmt_1 (pretty_printer *buffer, gimple *gs, int spc,
       break;
 
     case GIMPLE_OMP_SECTIONS:
-      dump_gimple_omp_sections (buffer, as_a <gomp_sections *> (gs),
+      dump_gimple_omp_sections (buffer, as_a <const gomp_sections *> (gs),
 				spc, flags);
       break;
 
@@ -2698,49 +2700,50 @@ pp_gimple_stmt_1 (pretty_printer *buffer, gimple *gs, int spc,
       break;
 
     case GIMPLE_OMP_ORDERED:
-      dump_gimple_omp_ordered (buffer, as_a <gomp_ordered *> (gs), spc,
+      dump_gimple_omp_ordered (buffer, as_a <const gomp_ordered *> (gs), spc,
 			       flags);
       break;
 
     case GIMPLE_OMP_SCAN:
-      dump_gimple_omp_scan (buffer, as_a <gomp_scan *> (gs), spc,
+      dump_gimple_omp_scan (buffer, as_a <const gomp_scan *> (gs), spc,
 			    flags);
       break;
 
     case GIMPLE_OMP_CRITICAL:
-      dump_gimple_omp_critical (buffer, as_a <gomp_critical *> (gs), spc,
+      dump_gimple_omp_critical (buffer, as_a <const gomp_critical *> (gs), spc,
 				flags);
       break;
 
     case GIMPLE_CATCH:
-      dump_gimple_catch (buffer, as_a <gcatch *> (gs), spc, flags);
+      dump_gimple_catch (buffer, as_a <const gcatch *> (gs), spc, flags);
       break;
 
     case GIMPLE_EH_FILTER:
-      dump_gimple_eh_filter (buffer, as_a <geh_filter *> (gs), spc, flags);
+      dump_gimple_eh_filter (buffer, as_a <const geh_filter *> (gs), spc,
+			     flags);
       break;
 
     case GIMPLE_EH_MUST_NOT_THROW:
       dump_gimple_eh_must_not_throw (buffer,
-				     as_a <geh_mnt *> (gs),
+				     as_a <const geh_mnt *> (gs),
 				     spc, flags);
       break;
 
     case GIMPLE_EH_ELSE:
-      dump_gimple_eh_else (buffer, as_a <geh_else *> (gs), spc, flags);
+      dump_gimple_eh_else (buffer, as_a <const geh_else *> (gs), spc, flags);
       break;
 
     case GIMPLE_RESX:
-      dump_gimple_resx (buffer, as_a <gresx *> (gs), spc, flags);
+      dump_gimple_resx (buffer, as_a <const gresx *> (gs), spc, flags);
       break;
 
     case GIMPLE_EH_DISPATCH:
-      dump_gimple_eh_dispatch (buffer, as_a <geh_dispatch *> (gs), spc,
+      dump_gimple_eh_dispatch (buffer, as_a <const geh_dispatch *> (gs), spc,
 			       flags);
       break;
 
     case GIMPLE_DEBUG:
-      dump_gimple_debug (buffer, as_a <gdebug *> (gs), spc, flags);
+      dump_gimple_debug (buffer, as_a <const gdebug *> (gs), spc, flags);
       break;
 
     case GIMPLE_PREDICT:
@@ -2754,7 +2757,7 @@ pp_gimple_stmt_1 (pretty_printer *buffer, gimple *gs, int spc,
       break;
 
     case GIMPLE_TRANSACTION:
-      dump_gimple_transaction (buffer, as_a <gtransaction *> (gs), spc,
+      dump_gimple_transaction (buffer, as_a <const gtransaction *> (gs), spc,
 			       flags);
       break;
 
diff --git a/gcc/gimple-pretty-print.h b/gcc/gimple-pretty-print.h
index 8d8e105..186f2cf 100644
--- a/gcc/gimple-pretty-print.h
+++ b/gcc/gimple-pretty-print.h
@@ -31,7 +31,8 @@ extern void print_gimple_stmt (FILE *, gimple *, int, dump_flags_t = TDF_NONE);
 extern void debug (gimple &ref);
 extern void debug (gimple *ptr);
 extern void print_gimple_expr (FILE *, gimple *, int, dump_flags_t = TDF_NONE);
-extern void pp_gimple_stmt_1 (pretty_printer *, gimple *, int, dump_flags_t);
+extern void pp_gimple_stmt_1 (pretty_printer *, const gimple *, int,
+			      dump_flags_t);
 extern void gimple_dump_bb (FILE *, basic_block, int, dump_flags_t);
 extern void gimple_dump_bb_for_graph (pretty_printer *, basic_block);
 extern void dump_ssaname_info_to_file (FILE *, tree, int);
diff --git a/gcc/gimple.h b/gcc/gimple.h
index 5a190b1..cc6bbd6 100644
--- a/gcc/gimple.h
+++ b/gcc/gimple.h
@@ -1018,6 +1018,14 @@ is_a_helper <gdebug *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const gdebug *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_DEBUG;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <ggoto *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_GOTO;
@@ -1026,6 +1034,14 @@ is_a_helper <ggoto *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const ggoto *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_GOTO;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <glabel *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_LABEL;
@@ -1034,6 +1050,14 @@ is_a_helper <glabel *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const glabel *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_LABEL;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <gresx *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_RESX;
@@ -1058,6 +1082,14 @@ is_a_helper <geh_else *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const geh_else *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_EH_ELSE;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <geh_filter *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_EH_FILTER;
@@ -1074,6 +1106,14 @@ is_a_helper <geh_mnt *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const geh_mnt *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_EH_MUST_NOT_THROW;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <gomp_atomic_load *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_OMP_ATOMIC_LOAD;
@@ -1220,6 +1260,14 @@ is_a_helper <gswitch *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const gswitch *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_SWITCH;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <gtransaction *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_TRANSACTION;
@@ -1236,6 +1284,14 @@ is_a_helper <gtry *>::test (gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const gtry *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_TRY;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <gimple_statement_wce *>::test (gimple *gs)
 {
   return gs->code == GIMPLE_WITH_CLEANUP_EXPR;
@@ -1430,6 +1486,14 @@ is_a_helper <const gphi *>::test (const gimple *gs)
 template <>
 template <>
 inline bool
+is_a_helper <const greturn *>::test (const gimple *gs)
+{
+  return gs->code == GIMPLE_RETURN;
+}
+
+template <>
+template <>
+inline bool
 is_a_helper <const gtransaction *>::test (const gimple *gs)
 {
   return gs->code == GIMPLE_TRANSACTION;
@@ -3255,7 +3319,7 @@ gimple_call_set_tail (gcall *s, bool tail_p)
 /* Return true if GIMPLE_CALL S is marked as a tail call.  */
 
 static inline bool
-gimple_call_tail_p (gcall *s)
+gimple_call_tail_p (const gcall *s)
 {
   return (s->subcode & GF_CALL_TAILCALL) != 0;
 }
@@ -3297,7 +3361,7 @@ gimple_call_set_return_slot_opt (gcall *s, bool return_slot_opt_p)
 /* Return true if S is marked for return slot optimization.  */
 
 static inline bool
-gimple_call_return_slot_opt_p (gcall *s)
+gimple_call_return_slot_opt_p (const gcall *s)
 {
   return (s->subcode & GF_CALL_RETURN_SLOT_OPT) != 0;
 }
@@ -3342,7 +3406,7 @@ gimple_call_set_va_arg_pack (gcall *s, bool pass_arg_pack_p)
    argument pack in its argument list.  */
 
 static inline bool
-gimple_call_va_arg_pack_p (gcall *s)
+gimple_call_va_arg_pack_p (const gcall *s)
 {
   return (s->subcode & GF_CALL_VA_ARG_PACK) != 0;
 }
@@ -3444,6 +3508,13 @@ gimple_call_use_set (gcall *call_stmt)
   return &call_stmt->call_used;
 }
 
+/* As above, but const.  */
+
+static inline const pt_solution *
+gimple_call_use_set (const gcall *call_stmt)
+{
+  return &call_stmt->call_used;
+}
 
 /* Return a pointer to the points-to solution for the set of call-used
    variables of the call CALL_STMT.  */
@@ -3454,16 +3525,24 @@ gimple_call_clobber_set (gcall *call_stmt)
   return &call_stmt->call_clobbered;
 }
 
+/* As above, but const.  */
+
+static inline const pt_solution *
+gimple_call_clobber_set (const gcall *call_stmt)
+{
+  return &call_stmt->call_clobbered;
+}
+
 
 /* Returns true if this is a GIMPLE_ASSIGN or a GIMPLE_CALL with a
    non-NULL lhs.  */
 
 static inline bool
-gimple_has_lhs (gimple *stmt)
+gimple_has_lhs (const gimple *stmt)
 {
   if (is_gimple_assign (stmt))
     return true;
-  if (gcall *call = dyn_cast <gcall *> (stmt))
+  if (const gcall *call = dyn_cast <const gcall *> (stmt))
     return gimple_call_lhs (call) != NULL_TREE;
   return false;
 }
@@ -3761,9 +3840,9 @@ gimple_bind_body_ptr (gbind *bind_stmt)
 /* Return the GIMPLE sequence contained in the GIMPLE_BIND statement GS.  */
 
 static inline gimple_seq
-gimple_bind_body (gbind *gs)
+gimple_bind_body (const gbind *gs)
 {
-  return *gimple_bind_body_ptr (gs);
+  return *gimple_bind_body_ptr (const_cast <gbind *> (gs));
 }
 
 
@@ -4035,9 +4114,9 @@ gimple_catch_handler_ptr (gcatch *catch_stmt)
    GIMPLE_CATCH statement CATCH_STMT.  */
 
 static inline gimple_seq
-gimple_catch_handler (gcatch *catch_stmt)
+gimple_catch_handler (const gcatch *catch_stmt)
 {
-  return *gimple_catch_handler_ptr (catch_stmt);
+  return *gimple_catch_handler_ptr (const_cast <gcatch *> (catch_stmt));
 }
 
 
@@ -4095,9 +4174,9 @@ gimple_eh_filter_failure_ptr (gimple *gs)
    statement fails.  */
 
 static inline gimple_seq
-gimple_eh_filter_failure (gimple *gs)
+gimple_eh_filter_failure (const gimple *gs)
 {
-  return *gimple_eh_filter_failure_ptr (gs);
+  return *gimple_eh_filter_failure_ptr (const_cast <gimple *> (gs));
 }
 
 
@@ -4124,7 +4203,7 @@ gimple_eh_filter_set_failure (geh_filter *eh_filter_stmt,
 /* Get the function decl to be called by the MUST_NOT_THROW region.  */
 
 static inline tree
-gimple_eh_must_not_throw_fndecl (geh_mnt *eh_mnt_stmt)
+gimple_eh_must_not_throw_fndecl (const geh_mnt *eh_mnt_stmt)
 {
   return eh_mnt_stmt->fndecl;
 }
@@ -4147,9 +4226,9 @@ gimple_eh_else_n_body_ptr (geh_else *eh_else_stmt)
 }
 
 static inline gimple_seq
-gimple_eh_else_n_body (geh_else *eh_else_stmt)
+gimple_eh_else_n_body (const geh_else *eh_else_stmt)
 {
-  return *gimple_eh_else_n_body_ptr (eh_else_stmt);
+  return *gimple_eh_else_n_body_ptr (const_cast <geh_else *> (eh_else_stmt));
 }
 
 static inline gimple_seq *
@@ -4159,9 +4238,9 @@ gimple_eh_else_e_body_ptr (geh_else *eh_else_stmt)
 }
 
 static inline gimple_seq
-gimple_eh_else_e_body (geh_else *eh_else_stmt)
+gimple_eh_else_e_body (const geh_else *eh_else_stmt)
 {
-  return *gimple_eh_else_e_body_ptr (eh_else_stmt);
+  return *gimple_eh_else_e_body_ptr (const_cast <geh_else *> (eh_else_stmt));
 }
 
 static inline void
@@ -4225,9 +4304,9 @@ gimple_try_eval_ptr (gimple *gs)
 /* Return the sequence of statements used as the body for GIMPLE_TRY GS.  */
 
 static inline gimple_seq
-gimple_try_eval (gimple *gs)
+gimple_try_eval (const gimple *gs)
 {
-  return *gimple_try_eval_ptr (gs);
+  return *gimple_try_eval_ptr (const_cast <gimple *> (gs));
 }
 
 
@@ -4246,9 +4325,9 @@ gimple_try_cleanup_ptr (gimple *gs)
    GIMPLE_TRY GS.  */
 
 static inline gimple_seq
-gimple_try_cleanup (gimple *gs)
+gimple_try_cleanup (const gimple *gs)
 {
-  return *gimple_try_cleanup_ptr (gs);
+  return *gimple_try_cleanup_ptr (const_cast <gimple *> (gs));
 }
 
 
@@ -4407,6 +4486,13 @@ gimple_phi_arg (gphi *gs, unsigned index)
   return &(gs->args[index]);
 }
 
+static inline const phi_arg_d *
+gimple_phi_arg (const gphi *gs, unsigned index)
+{
+  gcc_gimple_checking_assert (index < gs->nargs);
+  return &(gs->args[index]);
+}
+
 static inline struct phi_arg_d *
 gimple_phi_arg (gimple *gs, unsigned index)
 {
@@ -4446,7 +4532,7 @@ phi_nodes_ptr (basic_block bb)
 /* Return the tree operand for argument I of PHI node GS.  */
 
 static inline tree
-gimple_phi_arg_def (gphi *gs, size_t index)
+gimple_phi_arg_def (const gphi *gs, size_t index)
 {
   return gimple_phi_arg (gs, index)->def;
 }
@@ -4469,7 +4555,7 @@ gimple_phi_arg_def_ptr (gphi *phi, size_t index)
 /* Return the edge associated with argument I of phi node PHI.  */
 
 static inline edge
-gimple_phi_arg_edge (gphi *phi, size_t i)
+gimple_phi_arg_edge (const gphi *phi, size_t i)
 {
   return EDGE_PRED (gimple_bb (phi), i);
 }
@@ -4477,7 +4563,7 @@ gimple_phi_arg_edge (gphi *phi, size_t i)
 /* Return the source location of gimple argument I of phi node PHI.  */
 
 static inline location_t
-gimple_phi_arg_location (gphi *phi, size_t i)
+gimple_phi_arg_location (const gphi *phi, size_t i)
 {
   return gimple_phi_arg (phi, i)->locus;
 }
@@ -4501,7 +4587,7 @@ gimple_phi_arg_set_location (gphi *phi, size_t i, location_t loc)
 /* Return TRUE if argument I of phi node PHI has a location record.  */
 
 static inline bool
-gimple_phi_arg_has_location (gphi *phi, size_t i)
+gimple_phi_arg_has_location (const gphi *phi, size_t i)
 {
   return gimple_phi_arg_location (phi, i) != UNKNOWN_LOCATION;
 }
@@ -4669,7 +4755,7 @@ gimple_debug_bind_p (const gimple *s)
 /* Return the variable bound in a GIMPLE_DEBUG bind statement.  */
 
 static inline tree
-gimple_debug_bind_get_var (gimple *dbg)
+gimple_debug_bind_get_var (const gimple *dbg)
 {
   GIMPLE_CHECK (dbg, GIMPLE_DEBUG);
   gcc_gimple_checking_assert (gimple_debug_bind_p (dbg));
@@ -4680,7 +4766,7 @@ gimple_debug_bind_get_var (gimple *dbg)
    statement.  */
 
 static inline tree
-gimple_debug_bind_get_value (gimple *dbg)
+gimple_debug_bind_get_value (const gimple *dbg)
 {
   GIMPLE_CHECK (dbg, GIMPLE_DEBUG);
   gcc_gimple_checking_assert (gimple_debug_bind_p (dbg));
@@ -4761,7 +4847,7 @@ gimple_debug_source_bind_p (const gimple *s)
 /* Return the variable bound in a GIMPLE_DEBUG source bind statement.  */
 
 static inline tree
-gimple_debug_source_bind_get_var (gimple *dbg)
+gimple_debug_source_bind_get_var (const gimple *dbg)
 {
   GIMPLE_CHECK (dbg, GIMPLE_DEBUG);
   gcc_gimple_checking_assert (gimple_debug_source_bind_p (dbg));
@@ -4772,7 +4858,7 @@ gimple_debug_source_bind_get_var (gimple *dbg)
    statement.  */
 
 static inline tree
-gimple_debug_source_bind_get_value (gimple *dbg)
+gimple_debug_source_bind_get_value (const gimple *dbg)
 {
   GIMPLE_CHECK (dbg, GIMPLE_DEBUG);
   gcc_gimple_checking_assert (gimple_debug_source_bind_p (dbg));
@@ -4873,9 +4959,9 @@ gimple_omp_body_ptr (gimple *gs)
 /* Return the body for the OMP statement GS.  */
 
 static inline gimple_seq
-gimple_omp_body (gimple *gs)
+gimple_omp_body (const gimple *gs)
 {
-  return *gimple_omp_body_ptr (gs);
+  return *gimple_omp_body_ptr (const_cast <gimple *> (gs));
 }
 
 /* Set BODY to be the body for the OMP statement GS.  */
@@ -5140,9 +5226,9 @@ gimple_omp_for_set_clauses (gimple *gs, tree clauses)
 /* Get the collapse count of the OMP_FOR statement GS.  */
 
 static inline size_t
-gimple_omp_for_collapse (gimple *gs)
+gimple_omp_for_collapse (const gimple *gs)
 {
-  gomp_for *omp_for_stmt = as_a <gomp_for *> (gs);
+  const gomp_for *omp_for_stmt = as_a <const gomp_for *> (gs);
   return omp_for_stmt->collapse;
 }
 
@@ -5317,9 +5403,9 @@ gimple_omp_for_pre_body_ptr (gimple *gs)
    statement GS starts.  */
 
 static inline gimple_seq
-gimple_omp_for_pre_body (gimple *gs)
+gimple_omp_for_pre_body (const gimple *gs)
 {
-  return *gimple_omp_for_pre_body_ptr (gs);
+  return *gimple_omp_for_pre_body_ptr (const_cast <gimple *> (gs));
 }
 
 
@@ -6304,7 +6390,7 @@ gimple_transaction_body_ptr (gtransaction *transaction_stmt)
 /* Return the body for the GIMPLE_TRANSACTION statement TRANSACTION_STMT.  */
 
 static inline gimple_seq
-gimple_transaction_body (gtransaction *transaction_stmt)
+gimple_transaction_body (const gtransaction *transaction_stmt)
 {
   return transaction_stmt->body;
 }
diff --git a/gcc/tree-eh.c b/gcc/tree-eh.c
index 54502e6..b996f49 100644
--- a/gcc/tree-eh.c
+++ b/gcc/tree-eh.c
@@ -139,19 +139,19 @@ remove_stmt_from_eh_lp (gimple *t)
    statement is not recorded in the region table.  */
 
 int
-lookup_stmt_eh_lp_fn (struct function *ifun, gimple *t)
+lookup_stmt_eh_lp_fn (struct function *ifun, const gimple *t)
 {
   if (ifun->eh->throw_stmt_table == NULL)
     return 0;
 
-  int *lp_nr = ifun->eh->throw_stmt_table->get (t);
+  int *lp_nr = ifun->eh->throw_stmt_table->get (const_cast <gimple *> (t));
   return lp_nr ? *lp_nr : 0;
 }
 
 /* Likewise, but always use the current function.  */
 
 int
-lookup_stmt_eh_lp (gimple *t)
+lookup_stmt_eh_lp (const gimple *t)
 {
   /* We can get called from initialized data when -fnon-call-exceptions
      is on; prevent crash.  */
diff --git a/gcc/tree-eh.h b/gcc/tree-eh.h
index 511bb84..ca3b521 100644
--- a/gcc/tree-eh.h
+++ b/gcc/tree-eh.h
@@ -27,8 +27,8 @@ extern void using_eh_for_cleanups (void);
 extern void add_stmt_to_eh_lp (gimple *, int);
 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple *);
 extern bool remove_stmt_from_eh_lp (gimple *);
-extern int lookup_stmt_eh_lp_fn (struct function *, gimple *);
-extern int lookup_stmt_eh_lp (gimple *);
+extern int lookup_stmt_eh_lp_fn (struct function *, const gimple *);
+extern int lookup_stmt_eh_lp (const gimple *);
 extern bool make_eh_dispatch_edges (geh_dispatch *);
 extern void make_eh_edges (gimple *);
 extern edge redirect_eh_edge (edge, basic_block);
diff --git a/gcc/tree-ssa-alias.h b/gcc/tree-ssa-alias.h
index 6d72c2f..de85312 100644
--- a/gcc/tree-ssa-alias.h
+++ b/gcc/tree-ssa-alias.h
@@ -162,7 +162,7 @@ extern void dump_alias_stats (FILE *);
 
 /* In tree-ssa-structalias.c  */
 extern unsigned int compute_may_aliases (void);
-extern bool pt_solution_empty_p (struct pt_solution *);
+extern bool pt_solution_empty_p (const pt_solution *);
 extern bool pt_solution_singleton_or_null_p (struct pt_solution *, unsigned *);
 extern bool pt_solution_includes_global (struct pt_solution *);
 extern bool pt_solution_includes (struct pt_solution *, const_tree);
diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index f7a17eb..bc50a9b 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -6804,7 +6804,7 @@ pt_solution_ior_into (struct pt_solution *dest, struct pt_solution *src)
 /* Return true if the points-to solution *PT is empty.  */
 
 bool
-pt_solution_empty_p (struct pt_solution *pt)
+pt_solution_empty_p (const pt_solution *pt)
 {
   if (pt->anything
       || pt->nonlocal)