re PR rtl-optimization/87761 ([MIPS] New FAIL: gcc.target/mips/fix-r4000-10.c …

re PR rtl-optimization/87761 ([MIPS] New FAIL: gcc.target/mips/fix-r4000-10.c   -O1 start with r265398)

	PR rtl-optimization/87761
	PR rtl-optimization/89826
	* regcprop.c (copyprop_hardreg_forward_1): Move may_trap_p test
	slightly later.
	(pass_cprop_hardreg::execute): Call df_analyze after adding the
	note problem to get REG_DEAD/REG_UNUSED notes updated.

	PR rtl-optimization/87761
	PR rtl-optimization/89826
	* gcc.c-torture/execute/pr89826.c: New test.

From-SVN: r269967

gcc/ChangeLog

+2019-03-27  Jeff Law  <law@redhat.com>
+
+
+	PR rtl-optimization/87761
+	PR rtl-optimization/89826
+	* regcprop.c (copyprop_hardreg_forward_1): Move may_trap_p test
+	slightly later.
+	(pass_cprop_hardreg::execute): Call df_analyze after adding the
+	note problem to get REG_DEAD/REG_UNUSED notes updated.
+
 2019-03-27  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/89463

gcc/regcprop.c

@@ -800,9 +800,9 @@ copyprop_hardreg_forward_1 (basic_block bb, struct value_data *vd)
 
       /* Detect obviously dead sets (via REG_UNUSED notes) and remove them.  */
       if (set
-	  && !may_trap_p (set)
 	  && !RTX_FRAME_RELATED_P (insn)
 	  && INSN_P (insn)
+	  && !may_trap_p (set)
 	  && find_reg_note (insn, REG_UNUSED, SET_DEST (set))
 	  && !side_effects_p (SET_SRC (set))
 	  && !side_effects_p (SET_DEST (set)))
@@ -1293,7 +1293,10 @@ pass_cprop_hardreg::execute (function *fun)
   auto_sbitmap visited (last_basic_block_for_fn (fun));
   bitmap_clear (visited);
 
+  /* We need accurate notes.  Earlier passes such as if-conversion may
+     leave notes in an inconsistent state.  */
   df_note_add_problem ();
+  df_analyze ();
 
   /* It is tempting to set DF_LR_RUN_DCE, but DCE may choose to delete
      an insn and this pass would not have visibility into the removal.

gcc/testsuite/ChangeLog

+2019-03-26  Jeff Law  <law@redhat.com>
+
+	PR rtl-optimization/87761
+	PR rtl-optimization/89826
+	* gcc.c-torture/execute/pr89826.c: New test.
+
 2019-03-27  Richard Biener  <rguenther@suse.de>
 
 	* gcc.dg/torture/20190327-1.c: New testcase.

gcc/testsuite/gcc.c-torture/execute/pr89826.c

+typedef unsigned int u32;
+typedef unsigned long long u64;
+u64 a;
+u32 b;
+
+u64
+foo (u32 d)
+{
+  a -= d ? 0 : ~a;
+  return a + b;
+}
+
+int
+main (void)
+{
+  u64 x = foo (2);
+  if (x != 0)
+    __builtin_abort();
+  return 0;
+}
+