* function.c (assign_parm_setup_reg): Prevent sharing in another case.

From-SVN: r237703

gcc/ChangeLog

+2016-06-22  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* function.c (assign_parm_setup_reg): Prevent sharing in another case.
+
 2016-06-22  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	* config/i386/i386.c (print_reg): Emit an error message on attempt to

gcc/function.c

@@ -3314,6 +3314,8 @@ assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
 	  set_mem_attributes (parmreg, parm, 1);
 	}
 
+      /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
+	 the debug info in case it is not legitimate.  */
       if (GET_MODE (parmreg) != GET_MODE (rtl))
 	{
 	  rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
@@ -3323,7 +3325,8 @@ assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
 			     all->last_conversion_insn);
 	  emit_move_insn (tempreg, rtl);
 	  tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
-	  emit_move_insn (parmreg, tempreg);
+	  emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
+			  tempreg);
 	  all->first_conversion_insn = get_insns ();
 	  all->last_conversion_insn = get_last_insn ();
 	  end_sequence ();
@@ -3331,7 +3334,7 @@ assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
 	  did_conversion = true;
 	}
       else
-	emit_move_insn (parmreg, rtl);
+	emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
 
       rtl = parmreg;
 

gcc/testsuite/ChangeLog

+2016-06-22  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gcc.dg/guality/param-5.c: New test.
+
 2016-06-22  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	* gcc.target/i386/asm-flag-7.c: New test.

gcc/testsuite/gcc.dg/guality/param-5.c

+/* { dg-do run } */
+/* { dg-options "-g" } */
+/* { dg-skip-if "" { *-*-* }  { "*" } { "-O0" } } */
+
+typedef __UINTPTR_TYPE__ uintptr_t;
+
+typedef struct { uintptr_t pa; uintptr_t pb; } fatp_t
+  __attribute__ ((aligned (2 * __alignof__ (uintptr_t))));
+
+__attribute__((noinline, noclone)) void
+clear_stack (void)
+{
+  char a[128 * 1024 + 128];
+
+  __builtin_memset (a, 0, sizeof (a));
+}
+
+__attribute__((noinline, noclone)) void
+foo (fatp_t str, int count)
+{
+  char a[128 * 1024];
+
+  if (count > 0)
+    foo (str, count - 1);
+  clear_stack ();
+  count--;  /* BREAK */
+}
+
+int
+main (void)
+{
+  fatp_t ptr = { 31415927, 27182818 };
+  foo (ptr, 1);
+  return 0;
+}
+
+/* { dg-final { gdb-test 26 "str.pa" "31415927" } } */
+/* { dg-final { gdb-test 26 "str.pb" "27182818" } } */