Provide extra checking for phi argument access from edge

The following adds checking that the edge we query an associated
PHI arg for is related to the PHI node.  Triggered by questionable
code in one of my reviews.

	* gimple.h (gimple_phi_arg): New const overload.
	(gimple_phi_arg_def): Make gimple arg const.
	(gimple_phi_arg_def_from_edge): New inline function.
	* tree-phinodes.h (gimple_phi_arg_imm_use_ptr_from_edge):
	Likewise.
	* tree-ssa-operands.h (PHI_ARG_DEF_FROM_EDGE): Direct to
	new inline function.
	(PHI_ARG_DEF_PTR_FROM_EDGE): Likewise.

diff --git a/gcc/gimple.h b/gcc/gimple.h
index daf55242f682fdc5fb7350f37d7b7bba577802b3..d3750f95d7936ef987464d4f38d701187b617031 100644 (file)
--- a/gcc/gimple.h
+++ b/gcc/gimple.h
@@ -4633,6 +4633,13 @@ gimple_phi_arg (const gphi *gs, unsigned index)
   return &(gs->args[index]);
 }
 
+inline const phi_arg_d *
+gimple_phi_arg (const gimple *gs, unsigned index)
+{
+  const gphi *phi_stmt = as_a <const gphi *> (gs);
+  return gimple_phi_arg (phi_stmt, index);
+}
+
 inline struct phi_arg_d *
 gimple_phi_arg (gimple *gs, unsigned index)
 {
@@ -4678,11 +4685,27 @@ gimple_phi_arg_def (const gphi *gs, size_t index)
 }
 
 inline tree
-gimple_phi_arg_def (gimple *gs, size_t index)
+gimple_phi_arg_def (const gimple *gs, size_t index)
 {
   return gimple_phi_arg (gs, index)->def;
 }
 
+/* Return the tree operand for the argument associated with
+   edge E of PHI node GS.  */
+
+inline tree
+gimple_phi_arg_def_from_edge (const gphi *gs, const_edge e)
+{
+  gcc_checking_assert (e->dest == gimple_bb (gs));
+  return gimple_phi_arg (gs, e->dest_idx)->def;
+}
+
+inline tree
+gimple_phi_arg_def_from_edge (const gimple *gs, const_edge e)
+{
+  gcc_checking_assert (e->dest == gimple_bb (gs));
+  return gimple_phi_arg (gs, e->dest_idx)->def;
+}
 
 /* Return a pointer to the tree operand for argument I of phi node PHI.  */
 

diff --git a/gcc/tree-phinodes.h b/gcc/tree-phinodes.h
index 932a461e987d4196be74bb4d5164fe9a03f09010..be114e317b4277e1403e2124e2cbe7fe4cd06883 100644 (file)
--- a/gcc/tree-phinodes.h
+++ b/gcc/tree-phinodes.h
@@ -37,6 +37,13 @@ gimple_phi_arg_imm_use_ptr (gimple *gs, int i)
   return &gimple_phi_arg (gs, i)->imm_use;
 }
 
+inline use_operand_p
+gimple_phi_arg_imm_use_ptr_from_edge (gimple *gs, const_edge e)
+{
+  gcc_checking_assert (e->dest == gimple_bb (gs));
+  return &gimple_phi_arg (gs, e->dest_idx)->imm_use;
+}
+
 /* Return the phi argument which contains the specified use.  */
 
 inline int

diff --git a/gcc/tree-ssa-operands.h b/gcc/tree-ssa-operands.h
index ae36bcdb893e3a4c80f594f9e6776838769378c1..c7b74e046d01af7537a168843d169918797a677f 100644 (file)
--- a/gcc/tree-ssa-operands.h
+++ b/gcc/tree-ssa-operands.h
@@ -83,9 +83,9 @@ struct GTY(()) ssa_operands {
 #define SET_PHI_ARG_DEF(PHI, I, V)                                     \
                                SET_USE (PHI_ARG_DEF_PTR ((PHI), (I)), (V))
 #define PHI_ARG_DEF_FROM_EDGE(PHI, E)                                  \
-                               PHI_ARG_DEF ((PHI), (E)->dest_idx)
+                               gimple_phi_arg_def_from_edge ((PHI), (E))
 #define PHI_ARG_DEF_PTR_FROM_EDGE(PHI, E)                              \
-                               PHI_ARG_DEF_PTR ((PHI), (E)->dest_idx)
+                               gimple_phi_arg_imm_use_ptr_from_edge ((PHI), (E))
 #define PHI_ARG_INDEX_FROM_USE(USE)   phi_arg_index_from_use (USE)