re PR target/91767 (After r274953, clang-compiled xgcc segfaults during RTL pass: stv)

2019-09-20  Richard Biener  <rguenther@suse.de>

	PR target/91767
	* config/i386/i386-features.c (general_scalar_chain::convert_registers):
	Ensure there's a sequence point between allocating the new register
	and passing a reference to a reg via regno_reg_rtx.

From-SVN: r275989

gcc/ChangeLog

+2019-09-20  Richard Biener  <rguenther@suse.de>
+
+	PR target/91767
+	* config/i386/i386-features.c (general_scalar_chain::convert_registers):
+	Ensure there's a sequence point between allocating the new register
+	and passing a reference to a reg via regno_reg_rtx.
+
 2019-09-20  Martin Jambor  <mjambor@suse.cz>
 
         * coretypes.h (cgraph_edge): Declare.

gcc/config/i386/i386-features.c

@@ -1210,7 +1210,10 @@ general_scalar_chain::convert_registers ()
   bitmap_iterator bi;
   unsigned id;
   EXECUTE_IF_SET_IN_BITMAP (defs_conv, 0, id, bi)
-    defs_map.put (regno_reg_rtx[id], gen_reg_rtx (smode));
+    {
+      rtx chain_reg = gen_reg_rtx (smode);
+      defs_map.put (regno_reg_rtx[id], chain_reg);
+    }
   EXECUTE_IF_SET_IN_BITMAP (insns_conv, 0, id, bi)
     for (df_ref ref = DF_INSN_UID_DEFS (id); ref; ref = DF_REF_NEXT_LOC (ref))
       if (bitmap_bit_p (defs_conv, DF_REF_REGNO (ref)))