[gimple-classes, committed 65/92] Make gimple_phi_arg_location require a gimple_phi.

[David Malcolm <dmalcolm at redhat dot com>]

This corresponds to:
  [PATCH 67/89] Make gimple_phi_arg_location require a gimple_phi.
  https://gcc.gnu.org/ml/gcc-patches/2014-04/msg01182.html
from the original 89-patch kit

That earlier patch was approved by Jeff:
> OK once prerequisites go in.
in https://gcc.gnu.org/ml/gcc-patches/2014-05/msg00848.html

gcc/
	* gimple.h (gimple_phi_arg_location): Require a gimple_phi.

	* tree-into-ssa.c (rewrite_update_phi_arguments): Replace a check
	for code GIMPLE_PHI with a dyn_cast and a new local.
	* tree-ssa-ter.c (ter_is_replaceable_p): Likewise.

	* tree-ssa-live.c (remove_unused_locals): Replace a
	gimple_stmt_iterator with a gimple_phi_iterator, using it to make
	local "phi" be a gimple_phi.
	* tree-ssa-phiopt.c (tree_ssa_phiopt_worker): Likewise.

	* tree-ssa-phiopt.c (conditional_replacement): Require a gimple_phi.
	(single_non_singleton_phi_for_edges): Return a gimple_phi; update
	local to be a gimple_phi, adding checked casts since we're working
	on a sequence of gimple_phi.
	(conditional_replacement): Require a gimple_phi.

	* tree-ssa-threadupdate.c (get_value_locus_in_path): Strengthen
	type of local "def_phi" to gimple_phi by replacing a check of the
	code for GIMPLE_PHI with a dyn_cast<gimple_phi>.
---
 gcc/ChangeLog.gimple-classes | 25 +++++++++++++++++++++++++
 gcc/gimple.h                 |  6 +++---
 gcc/tree-into-ssa.c          |  7 ++++---
 gcc/tree-ssa-live.c          |  6 ++++--
 gcc/tree-ssa-phiopt.c        | 17 +++++++++--------
 gcc/tree-ssa-ter.c           |  4 ++--
 gcc/tree-ssa-threadupdate.c  |  6 +++---
 7 files changed, 50 insertions(+), 21 deletions(-)

diff --git a/gcc/ChangeLog.gimple-classes b/gcc/ChangeLog.gimple-classes
index 5a271ca..f2f9a05 100644
--- a/gcc/ChangeLog.gimple-classes
+++ b/gcc/ChangeLog.gimple-classes
@@ -1,5 +1,30 @@
 2014-10-24  David Malcolm  <dmalcolm@redhat.com>
 
+	Make gimple_phi_arg_location require a gimple_phi.
+
+	* gimple.h (gimple_phi_arg_location): Require a gimple_phi.
+
+	* tree-into-ssa.c (rewrite_update_phi_arguments): Replace a check
+	for code GIMPLE_PHI with a dyn_cast and a new local.
+	* tree-ssa-ter.c (ter_is_replaceable_p): Likewise.
+
+	* tree-ssa-live.c (remove_unused_locals): Replace a
+	gimple_stmt_iterator with a gimple_phi_iterator, using it to make
+	local "phi" be a gimple_phi.
+	* tree-ssa-phiopt.c (tree_ssa_phiopt_worker): Likewise.
+
+	* tree-ssa-phiopt.c (conditional_replacement): Require a gimple_phi.
+	(single_non_singleton_phi_for_edges): Return a gimple_phi; update
+	local to be a gimple_phi, adding checked casts since we're working
+	on a sequence of gimple_phi.
+	(conditional_replacement): Require a gimple_phi.
+
+	* tree-ssa-threadupdate.c (get_value_locus_in_path): Strengthen
+	type of local "def_phi" to gimple_phi by replacing a check of the
+	code for GIMPLE_PHI with a dyn_cast<gimple_phi>.
+
+2014-10-24  David Malcolm  <dmalcolm@redhat.com>
+
 	Make gimple_phi_arg_location_from_edge require a gimple_phi
 
 	* gimple.h (gimple_phi_arg_location_from_edge): Require a
diff --git a/gcc/gimple.h b/gcc/gimple.h
index 0c8db97..688c375 100644
--- a/gcc/gimple.h
+++ b/gcc/gimple.h
@@ -3972,12 +3972,12 @@ gimple_phi_arg_edge (gimple_phi phi, size_t i)
   return EDGE_PRED (gimple_bb (phi), i);
 }
 
-/* Return the source location of gimple argument I of phi node GS.  */
+/* Return the source location of gimple argument I of phi node PHI.  */
 
 static inline source_location
-gimple_phi_arg_location (gimple gs, size_t i)
+gimple_phi_arg_location (gimple_phi phi, size_t i)
 {
-  return gimple_phi_arg (gs, i)->locus;
+  return gimple_phi_arg (phi, i)->locus;
 }
 
 /* Return the source location of the argument on edge E of phi node PHI.  */
diff --git a/gcc/tree-into-ssa.c b/gcc/tree-into-ssa.c
index 9291105..b4e0e4b 100644
--- a/gcc/tree-into-ssa.c
+++ b/gcc/tree-into-ssa.c
@@ -2045,12 +2045,13 @@ rewrite_update_phi_arguments (basic_block bb)
 	      else
 		{
 		  gimple stmt = SSA_NAME_DEF_STMT (reaching_def);
+		  gimple_phi other_phi = dyn_cast <gimple_phi> (stmt);
 
 		  /* Single element PHI nodes  behave like copies, so get the
 		     location from the phi argument.  */
-		  if (gimple_code (stmt) == GIMPLE_PHI
-		      && gimple_phi_num_args (stmt) == 1)
-		    locus = gimple_phi_arg_location (stmt, 0);
+		  if (other_phi
+		      && gimple_phi_num_args (other_phi) == 1)
+		    locus = gimple_phi_arg_location (other_phi, 0);
 		  else
 		    locus = gimple_location (stmt);
 		}
diff --git a/gcc/tree-ssa-live.c b/gcc/tree-ssa-live.c
index 5157ff0..00fcbc3 100644
--- a/gcc/tree-ssa-live.c
+++ b/gcc/tree-ssa-live.c
@@ -819,12 +819,14 @@ remove_unused_locals (void)
 	    mark_all_vars_used (gimple_op_ptr (gsi_stmt (gsi), i));
 	}
 
-      for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+      for (gimple_phi_iterator gpi = gsi_start_phis (bb);
+	   !gsi_end_p (gpi);
+	   gsi_next (&gpi))
         {
           use_operand_p arg_p;
           ssa_op_iter i;
 	  tree def;
-	  gimple phi = gsi_stmt (gsi);
+	  gimple_phi phi = gpi.phi ();
 
 	  if (virtual_operand_p (gimple_phi_result (phi)))
 	    continue;
diff --git a/gcc/tree-ssa-phiopt.c b/gcc/tree-ssa-phiopt.c
index dfeefbe..df15a45 100644
--- a/gcc/tree-ssa-phiopt.c
+++ b/gcc/tree-ssa-phiopt.c
@@ -62,7 +62,7 @@ along with GCC; see the file COPYING3.  If not see
 
 static unsigned int tree_ssa_phiopt_worker (bool, bool);
 static bool conditional_replacement (basic_block, basic_block,
-				     edge, edge, gimple, tree, tree);
+				     edge, edge, gimple_phi, tree, tree);
 static int value_replacement (basic_block, basic_block,
 			      edge, edge, gimple, tree, tree);
 static bool minmax_replacement (basic_block, basic_block,
@@ -138,16 +138,16 @@ tree_ssa_cs_elim (void)
 
 /* Return the singleton PHI in the SEQ of PHIs for edges E0 and E1. */
 
-static gimple
+static gimple_phi
 single_non_singleton_phi_for_edges (gimple_seq seq, edge e0, edge e1)
 {
   gimple_stmt_iterator i;
-  gimple phi = NULL;
+  gimple_phi phi = NULL;
   if (gimple_seq_singleton_p (seq))
-    return gsi_stmt (gsi_start (seq));
+    return as_a <gimple_phi> (gsi_stmt (gsi_start (seq)));
   for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i))
     {
-      gimple p = gsi_stmt (i);
+      gimple_phi p = as_a <gimple_phi> (gsi_stmt (i));
       /* If the PHI arguments are equal then we can skip this PHI. */
       if (operand_equal_for_phi_arg_p (gimple_phi_arg_def (p, e0->dest_idx),
 				       gimple_phi_arg_def (p, e1->dest_idx)))
@@ -211,7 +211,8 @@ tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads)
 
   for (i = 0; i < n; i++)
     {
-      gimple cond_stmt, phi;
+      gimple cond_stmt;
+      gimple_phi phi;
       basic_block bb1, bb2;
       edge e1, e2;
       tree arg0, arg1;
@@ -322,7 +323,7 @@ tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads)
 	     so try that first. */
 	  for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
 	    {
-	      phi = gsi_stmt (gsi);
+	      phi = as_a <gimple_phi> (gsi_stmt (gsi));
 	      arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
 	      arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
 	      if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1) == 2)
@@ -433,7 +434,7 @@ replace_phi_edge_with_variable (basic_block cond_block,
 
 static bool
 conditional_replacement (basic_block cond_bb, basic_block middle_bb,
-			 edge e0, edge e1, gimple phi,
+			 edge e0, edge e1, gimple_phi phi,
 			 tree arg0, tree arg1)
 {
   tree result;
diff --git a/gcc/tree-ssa-ter.c b/gcc/tree-ssa-ter.c
index 78bedfc..d8ab499 100644
--- a/gcc/tree-ssa-ter.c
+++ b/gcc/tree-ssa-ter.c
@@ -428,8 +428,8 @@ ter_is_replaceable_p (gimple stmt)
       block1 = LOCATION_BLOCK (locus1);
       locus1 = LOCATION_LOCUS (locus1);
 
-      if (gimple_code (use_stmt) == GIMPLE_PHI)
-	locus2 = gimple_phi_arg_location (use_stmt, 
+      if (gimple_phi phi = dyn_cast <gimple_phi> (use_stmt))
+	locus2 = gimple_phi_arg_location (phi,
 					  PHI_ARG_INDEX_FROM_USE (use_p));
       else
 	locus2 = gimple_location (use_stmt);
diff --git a/gcc/tree-ssa-threadupdate.c b/gcc/tree-ssa-threadupdate.c
index 24920ca..883574c 100644
--- a/gcc/tree-ssa-threadupdate.c
+++ b/gcc/tree-ssa-threadupdate.c
@@ -419,14 +419,14 @@ get_value_locus_in_path (tree def, vec<jump_thread_edge *> *path,
 			 basic_block bb, int idx, source_location *locus)
 {
   tree arg;
-  gimple def_phi;
+  gimple_phi def_phi;
   basic_block def_bb;
 
   if (path == NULL || idx == 0)
     return def;
 
-  def_phi = SSA_NAME_DEF_STMT (def);
-  if (gimple_code (def_phi) != GIMPLE_PHI)
+  def_phi = dyn_cast <gimple_phi> (SSA_NAME_DEF_STMT (def));
+  if (!def_phi)
     return def;
 
   def_bb = gimple_bb (def_phi);
-- 
1.8.5.3