[PR 91831] Copy PARM_DECLs of artificial thunks

Hi,

I am quite surprised I did not catch this before but the new
ipa-param-manipulation does not copy PARM_DECLs when creating
artificial thinks (I think it originally did but then I somehow
removed during one cleanups).  Fixed by adding the capability at the
natural place.  It is triggered whenever context of the PARM_DECL that
is just taken from the original function does not match the target
fndecl rather than by some constructor parameter because in such
situation it is always the correct thing to do.

Bootstrapped and tested on x86_64-linux.  OK for trunk?

Thanks,

Martin

2019-09-24  Martin Jambor  <mjambor@suse.cz>

	PR ipa/91831
	* ipa-param-manipulation.c (carry_over_param): Make a method of
	ipa_param_body_adjustments, remove now unnecessary argument.  Also copy
	in case of a context mismatch.
	(ipa_param_body_adjustments::common_initialization): Adjust call to
	carry_over_param.
	* ipa-param-manipulation.h (class ipa_param_body_adjustments): Add
	private method carry_over_param.

	testsuite/
	* g++.dg/ipa/pr91831.C: New test.

From-SVN: r276094

gcc/ChangeLog

@@ -1,3 +1,14 @@
+2019-09-24  Martin Jambor  <mjambor@suse.cz>
+
+	PR ipa/91831
+	* ipa-param-manipulation.c (carry_over_param): Make a method of
+	ipa_param_body_adjustments, remove now unnecessary argument.  Also copy
+	in case of a context mismatch.
+	(ipa_param_body_adjustments::common_initialization): Adjust call to
+	carry_over_param.
+	* ipa-param-manipulation.h (class ipa_param_body_adjustments): Add
+	private method carry_over_param.
+
 2019-09-24  Martin Jambor  <mjambor@suse.cz>
 
 	PR ipa/91832

gcc/ipa-param-manipulation.c

@@ -906,18 +906,24 @@ ipa_param_body_adjustments::register_replacement (ipa_adjusted_param *apm,
   m_replacements.safe_push (psr);
 }
 
-/* Copy or not, as appropriate given ID, a pre-existing PARM_DECL T so that
-   it can be included in the parameters of the modified function.  */
+/* Copy or not, as appropriate given m_id and decl context, a pre-existing
+   PARM_DECL T so that it can be included in the parameters of the modified
+   function.  */
 
-static tree
-carry_over_param (tree t, struct copy_body_data *id)
+tree
+ipa_param_body_adjustments::carry_over_param (tree t)
 {
   tree new_parm;
-  if (id)
+  if (m_id)
     {
-      new_parm = remap_decl (t, id);
+      new_parm = remap_decl (t, m_id);
       if (TREE_CODE (new_parm) != PARM_DECL)
-	new_parm = id->copy_decl (t, id);
+	new_parm = m_id->copy_decl (t, m_id);
+    }
+  else if (DECL_CONTEXT (t) != m_fndecl)
+    {
+      new_parm = copy_node (t);
+      DECL_CONTEXT (new_parm) = m_fndecl;
     }
   else
     new_parm = t;
@@ -982,7 +988,7 @@ ipa_param_body_adjustments::common_initialization (tree old_fndecl,
 	  || apm->prev_clone_adjustment)
 	{
 	  kept[prev_index] = true;
-	  new_parm = carry_over_param (m_oparms[prev_index], m_id);
+	  new_parm = carry_over_param (m_oparms[prev_index]);
 	  m_new_decls.quick_push (new_parm);
 	}
       else if (apm->op == IPA_PARAM_OP_NEW

gcc/ipa-param-manipulation.h

@@ -370,6 +370,7 @@ public:
 private:
   void common_initialization (tree old_fndecl, tree *vars,
 			      vec<ipa_replace_map *, va_gc> *tree_map);
+  tree carry_over_param (tree t);
   unsigned get_base_index (ipa_adjusted_param *apm);
   ipa_param_body_replacement *lookup_replacement_1 (tree base,
 						    unsigned unit_offset);

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2019-09-24  Martin Jambor  <mjambor@suse.cz>
+
+	PR ipa/91831
+	* g++.dg/ipa/pr91831.C: New test.
+
 2019-09-24  Martin Jambor  <mjambor@suse.cz>
 
 	PR ipa/91832

gcc/testsuite/g++.dg/ipa/pr91831.C

@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 --param uninlined-thunk-insns=1000"  } */
+
+struct A {
+  virtual void m_fn1();
+};
+struct B {
+  virtual void *m_fn2(int, int) = 0;
+};
+struct C : A, B {
+  void *m_fn2(int, int) { return this; }
+};
+void *fn1(B &p1) { return p1.m_fn2(0, 0); }
+
+int main() {
+  C c;
+  fn1(c);
+  return 0;
+}