diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index 79e621a..2ec671f 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -1219,13 +1219,19 @@ ipa_get_jf_pass_through_result (struct ipa_jump_func *jfunc, tree input)
     return NULL_TREE;
 
   if (TREE_CODE_CLASS (ipa_get_jf_pass_through_operation (jfunc))
-      == tcc_comparison)
-    restype = boolean_type_node;
+      == tcc_unary)
+    res = fold_unary (ipa_get_jf_pass_through_operation (jfunc),
+		      TREE_TYPE (input), input);
   else
-    restype = TREE_TYPE (input);
-  res = fold_binary (ipa_get_jf_pass_through_operation (jfunc), restype,
-		     input, ipa_get_jf_pass_through_operand (jfunc));
-
+    {
+      if (TREE_CODE_CLASS (ipa_get_jf_pass_through_operation (jfunc))
+	  == tcc_comparison)
+	restype = boolean_type_node;
+      else
+	restype = TREE_TYPE (input);
+      res = fold_binary (ipa_get_jf_pass_through_operation (jfunc), restype,
+			 input, ipa_get_jf_pass_through_operand (jfunc));
+    }
   if (res && !is_gimple_ip_invariant (res))
     return NULL_TREE;
 
@@ -1857,13 +1863,32 @@ propagate_vr_accross_jump_function (cgraph_edge *cs,
   if (jfunc->type == IPA_JF_PASS_THROUGH)
     {
       struct ipa_node_params *caller_info = IPA_NODE_REF (cs->caller);
-      if (dest_lat->bottom_p ())
-	return false;
       int src_idx = ipa_get_jf_pass_through_formal_id (jfunc);
       src_lats = ipa_get_parm_lattices (caller_info, src_idx);
 
       if (ipa_get_jf_pass_through_operation (jfunc) == NOP_EXPR)
 	return dest_lat->meet_with (src_lats->m_value_range);
+      else if (param_type
+	       && (TREE_CODE_CLASS (ipa_get_jf_pass_through_operation (jfunc))
+		   == tcc_unary))
+	{
+	  value_range vr;
+	  memset (&vr, 0, sizeof (vr));
+	  tree operand_type = ipa_get_type (caller_info, src_idx);
+	  enum tree_code operation = ipa_get_jf_pass_through_operation (jfunc);
+
+	  if (src_lats->m_value_range.bottom_p ())
+	    return dest_lat->set_to_bottom ();
+
+	  extract_range_from_unary_expr (&vr,
+					 operation,
+					 param_type,
+					 &src_lats->m_value_range.m_vr,
+					 operand_type);
+	  if (vr.type == VR_RANGE
+	      || vr.type == VR_ANTI_RANGE)
+	    return dest_lat->meet_with (&vr);
+	}
     }
   else if (jfunc->type == IPA_JF_CONST)
     {
diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index 74fe199..6321fdd 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -446,6 +446,18 @@ ipa_set_jf_simple_pass_through (struct ipa_jump_func *jfunc, int formal_id,
   jfunc->value.pass_through.agg_preserved = agg_preserved;
 }
 
+/* Set JFUNC to be an unary pass through jump function.  */
+
+static void
+ipa_set_jf_unary_pass_through (struct ipa_jump_func *jfunc, int formal_id,
+			       enum tree_code operation)
+{
+  jfunc->type = IPA_JF_PASS_THROUGH;
+  jfunc->value.pass_through.operand = NULL_TREE;
+  jfunc->value.pass_through.formal_id = formal_id;
+  jfunc->value.pass_through.operation = operation;
+  jfunc->value.pass_through.agg_preserved = false;
+}
 /* Set JFUNC to be an arithmetic pass through jump function.  */
 
 static void
@@ -849,21 +861,19 @@ parm_preserved_before_stmt_p (struct ipa_func_body_info *fbi, int index,
   return !modified;
 }
 
-/* If STMT is an assignment that loads a value from an parameter declaration,
-   return the index of the parameter in ipa_node_params which has not been
-   modified.  Otherwise return -1.  */
+/* Main worker for load_from_unmodified_param and load_from_param.
+   If STMT is an assignment that loads a value from an parameter declaration,
+   return the index of the parameter in ipa_node_params.  Otherwise return -1.  */
 
 static int
-load_from_unmodified_param (struct ipa_func_body_info *fbi,
-			    vec<ipa_param_descriptor> descriptors,
-			    gimple *stmt)
+load_from_param_1 (struct ipa_func_body_info *fbi,
+		   vec<ipa_param_descriptor> descriptors,
+		   gimple *stmt)
 {
   int index;
   tree op1;
 
-  if (!gimple_assign_single_p (stmt))
-    return -1;
-
+  gcc_checking_assert (is_gimple_assign (stmt));
   op1 = gimple_assign_rhs1 (stmt);
   if (TREE_CODE (op1) != PARM_DECL)
     return -1;
@@ -876,6 +886,40 @@ load_from_unmodified_param (struct ipa_func_body_info *fbi,
   return index;
 }
 
+/* If STMT is an assignment that loads a value from an parameter declaration,
+   return the index of the parameter in ipa_node_params which has not been
+   modified.  Otherwise return -1.  */
+
+static int
+load_from_unmodified_param (struct ipa_func_body_info *fbi,
+			    vec<ipa_param_descriptor> descriptors,
+			    gimple *stmt)
+{
+  if (!gimple_assign_single_p (stmt))
+    return -1;
+
+  return load_from_param_1 (fbi, descriptors, stmt);
+}
+
+/* If STMT is an assignment that loads a value from an parameter declaration,
+   return the index of the parameter in ipa_node_params.  Otherwise return -1.  */
+
+static int
+load_from_param (struct ipa_func_body_info *fbi,
+		 vec<ipa_param_descriptor> descriptors,
+		 gimple *stmt)
+{
+  if (!is_gimple_assign (stmt))
+    return -1;
+
+  enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
+  if ((get_gimple_rhs_class (rhs_code) != GIMPLE_SINGLE_RHS)
+      && (get_gimple_rhs_class (rhs_code) != GIMPLE_UNARY_RHS))
+    return -1;
+
+  return load_from_param_1 (fbi, descriptors, stmt);
+}
+
 /* Return true if memory reference REF (which must be a load through parameter
    with INDEX) loads data that are known to be unmodified in this function
    before reaching statement STMT.  */
@@ -1109,6 +1153,7 @@ compute_complex_assign_jump_func (struct ipa_func_body_info *fbi,
   tree op1, tc_ssa, base, ssa;
   bool reverse;
   int index;
+  gimple *stmt2 = stmt;
 
   op1 = gimple_assign_rhs1 (stmt);
 
@@ -1117,13 +1162,16 @@ compute_complex_assign_jump_func (struct ipa_func_body_info *fbi,
       if (SSA_NAME_IS_DEFAULT_DEF (op1))
 	index = ipa_get_param_decl_index (info, SSA_NAME_VAR (op1));
       else
-	index = load_from_unmodified_param (fbi, info->descriptors,
-					    SSA_NAME_DEF_STMT (op1));
+	{
+	  index = load_from_param (fbi, info->descriptors,
+				   SSA_NAME_DEF_STMT (op1));
+	  stmt2 = SSA_NAME_DEF_STMT (op1);
+	}
       tc_ssa = op1;
     }
   else
     {
-      index = load_from_unmodified_param (fbi, info->descriptors, stmt);
+      index = load_from_param (fbi, info->descriptors, stmt);
       tc_ssa = gimple_assign_lhs (stmt);
     }
 
@@ -1147,6 +1195,11 @@ compute_complex_assign_jump_func (struct ipa_func_body_info *fbi,
 	  bool agg_p = parm_ref_data_pass_through_p (fbi, index, call, tc_ssa);
 	  ipa_set_jf_simple_pass_through (jfunc, index, agg_p);
 	}
+      else if (is_gimple_assign (stmt2)
+	       && (gimple_expr_code (stmt2) != NOP_EXPR)
+	       && (TREE_CODE_CLASS (gimple_expr_code (stmt2)) == tcc_unary))
+	ipa_set_jf_unary_pass_through (jfunc, index,
+				       gimple_assign_rhs_code (stmt2));
       return;
     }
 
@@ -2518,6 +2571,12 @@ update_jump_functions_after_inlining (struct cgraph_edge *cs,
 	      dst->value.ancestor.agg_preserved &=
 		src->value.pass_through.agg_preserved;
 	    }
+	  else if (src->type == IPA_JF_PASS_THROUGH
+		   && TREE_CODE_CLASS (src->value.pass_through.operation) == tcc_unary)
+	    {
+	      dst->value.ancestor.formal_id = src->value.pass_through.formal_id;
+	      dst->value.ancestor.agg_preserved = false;
+	    }
 	  else if (src->type == IPA_JF_ANCESTOR)
 	    {
 	      dst->value.ancestor.formal_id = src->value.ancestor.formal_id;
@@ -2583,6 +2642,8 @@ update_jump_functions_after_inlining (struct cgraph_edge *cs,
 			  && ipa_get_jf_pass_through_agg_preserved (src);
 			ipa_set_jf_simple_pass_through (dst, formal_id, agg_p);
 		      }
+		    else if (TREE_CODE_CLASS (operation) == tcc_unary)
+		      ipa_set_jf_unary_pass_through (dst, formal_id, operation);
 		    else
 		      {
 			tree operand = ipa_get_jf_pass_through_operand (src);
@@ -4666,6 +4727,9 @@ ipa_write_jump_function (struct output_block *ob,
 	  bp_pack_value (&bp, jump_func->value.pass_through.agg_preserved, 1);
 	  streamer_write_bitpack (&bp);
 	}
+      else if (TREE_CODE_CLASS (jump_func->value.pass_through.operation)
+	       == tcc_unary)
+	streamer_write_uhwi (ob, jump_func->value.pass_through.formal_id);
       else
 	{
 	  stream_write_tree (ob, jump_func->value.pass_through.operand, true);
@@ -4745,6 +4809,11 @@ ipa_read_jump_function (struct lto_input_block *ib,
 	  bool agg_preserved = bp_unpack_value (&bp, 1);
 	  ipa_set_jf_simple_pass_through (jump_func, formal_id, agg_preserved);
 	}
+      else if (TREE_CODE_CLASS (operation) == tcc_unary)
+	{
+	  int formal_id =  streamer_read_uhwi (ib);
+	  ipa_set_jf_unary_pass_through (jump_func, formal_id, operation);
+	}
       else
 	{
 	  tree operand = stream_read_tree (ib, data_in);
diff --git a/gcc/testsuite/g++.dg/torture/pr78268.C b/gcc/testsuite/g++.dg/torture/pr78268.C
index e69de29..ef4547c 100644
--- a/gcc/testsuite/g++.dg/torture/pr78268.C
+++ b/gcc/testsuite/g++.dg/torture/pr78268.C
@@ -0,0 +1,25 @@
+// { dg-do compile }
+typedef enum {} nsresult;
+
+struct A {
+      virtual nsresult m_fn1(bool);
+};
+
+struct B {
+      A *operator[](int);
+};
+
+struct C {
+      nsresult m_fn2(bool);
+        bool m_fn3(bool);
+	  B mDataSources;
+};
+nsresult C::m_fn2(bool p1)
+{
+  m_fn3(!p1);
+}
+
+bool C::m_fn3(bool p1)
+{
+  mDataSources[0]->m_fn1(p1);
+}
