tree-inline.c (remap_gimple_stmt): Do not subtitute handled components to clobber of return value.

	* tree-inline.c (remap_gimple_stmt): Do not subtitute handled components
	to clobber of return value.
	* g++.dg/lto/pr90990_0.C: New testcase.

From-SVN: r272925

gcc/ChangeLog

+2019-07-02  Jan Hubicka  <jh@suse.cz>
+
+	* tree-inline.c (remap_gimple_stmt): Do not subtitute handled components
+	to clobber of return value.
+
 2019-07-02  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* config/arm/cortex-a57.md (cortex_a57_neon_type): Use neon_arith_basic
 	for is_neon_type instructions that have not already been categorized.
 
-
 2019-07-02  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/58483

gcc/testsuite/ChangeLog

+2019-07-02  Jan Hubicka  <jh@suse.cz>
+
+	* g++.dg/lto/pr90990_0.C: New testcase.
+
 2019-07-02  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/58483

gcc/testsuite/g++.dg/lto/pr90990_0.C

+// { dg-lto-do link }
+/* { dg-extra-ld-options {  -r -nostdlib } } */
+class A {
+public:
+  float m_floats;
+  A() {}
+};
+class B {
+public:
+  A operator[](int);
+};
+class C {
+  B m_basis;
+
+public:
+  A operator()(A) {
+    m_basis[1] = m_basis[2];
+    A a;
+    return a;
+  }
+};
+class D {
+public:
+  C m_fn1();
+};
+class F {
+  A m_pivotInB;
+  F(D &, const A &);
+};
+F::F(D &p1, const A &p2) : m_pivotInB(p1.m_fn1()(p2)) {}
+

gcc/tree-inline.c

@@ -1757,6 +1757,18 @@ remap_gimple_stmt (gimple *stmt, copy_body_data *id)
 		return NULL;
 	    }
 	}
+     
+      /* We do not allow CLOBBERs of handled components.  In case
+	 returned value is stored via such handled component, remove
+	 the clobber so stmt verifier is happy.  */
+      if (gimple_clobber_p (stmt)
+	  && TREE_CODE (gimple_assign_lhs (stmt)) == RESULT_DECL)
+	{
+	  tree remapped = remap_decl (gimple_assign_lhs (stmt), id);
+	  if (!DECL_P (remapped)
+	      && TREE_CODE (remapped) != MEM_REF)
+	    return NULL;
+	}
 
       if (gimple_debug_bind_p (stmt))
 	{