re PR target/90723 (pr88598-2.c segfaults with -msve-vector-bits=256)

2019-07-15  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>

	PR target/90723
	* recog.h (temporary_volatile_ok): New class.
	* config/aarch64/aarch64.c (aarch64_emit_sve_pred_move): Set
	volatile_ok temporarily to true using temporary_volatile_ok.
	* expr.c (emit_block_move_via_cpymem): Likewise.
	* optabs.c (maybe_legitimize_operand): Likewise.

From-SVN: r273466

gcc/ChangeLog

+2019-07-14  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>
+
+	PR target/90723
+	* recog.h (temporary_volatile_ok): New class.
+	* config/aarch64/aarch64.c (aarch64_emit_sve_pred_move): Set
+	volatile_ok temporarily to true using temporary_volatile_ok.
+	* expr.c (emit_block_move_via_cpymem): Likewise.
+	* optabs.c (maybe_legitimize_operand): Likewise.
+
 2019-07-13  Jakub Jelinek  <jakub@redhat.com>
 
 	* gimplify.c (struct gimplify_omp_ctx): Add order_concurrent member.

gcc/config/aarch64/aarch64.c

@@ -3457,6 +3457,7 @@ aarch64_emit_sve_pred_move (rtx dest, rtx pred, rtx src)
   create_output_operand (&ops[0], dest, mode);
   create_input_operand (&ops[1], pred, GET_MODE(pred));
   create_input_operand (&ops[2], src, mode);
+  temporary_volatile_ok v (true);
   expand_insn (code_for_aarch64_pred_mov (mode), 3, ops);
 }
 

gcc/expr.c

@@ -1732,8 +1732,6 @@ emit_block_move_via_cpymem (rtx x, rtx y, rtx size, unsigned int align,
 			    unsigned HOST_WIDE_INT max_size,
 			    unsigned HOST_WIDE_INT probable_max_size)
 {
-  int save_volatile_ok = volatile_ok;
-
   if (expected_align < align)
     expected_align = align;
   if (expected_size != -1)
@@ -1745,7 +1743,7 @@ emit_block_move_via_cpymem (rtx x, rtx y, rtx size, unsigned int align,
     }
 
   /* Since this is a move insn, we don't care about volatility.  */
-  volatile_ok = 1;
+  temporary_volatile_ok v (true);
 
   /* Try the most limited insn first, because there's no point
      including more than one in the machine description unless
@@ -1809,14 +1807,10 @@ emit_block_move_via_cpymem (rtx x, rtx y, rtx size, unsigned int align,
 		create_fixed_operand (&ops[8], NULL);
 	    }
 	  if (maybe_expand_insn (code, nops, ops))
-	    {
-	      volatile_ok = save_volatile_ok;
-	      return true;
-	    }
+	    return true;
 	}
     }
 
-  volatile_ok = save_volatile_ok;
   return false;
 }
 

gcc/optabs.c

@@ -7202,17 +7202,15 @@ maybe_legitimize_operand (enum insn_code icode, unsigned int opno,
 			  class expand_operand *op)
 {
   machine_mode mode, imode;
-  bool old_volatile_ok, result;
 
   mode = op->mode;
   switch (op->type)
     {
     case EXPAND_FIXED:
-      old_volatile_ok = volatile_ok;
-      volatile_ok = true;
-      result = maybe_legitimize_operand_same_code (icode, opno, op);
-      volatile_ok = old_volatile_ok;
-      return result;
+      {
+	temporary_volatile_ok v (true);
+	return maybe_legitimize_operand_same_code (icode, opno, op);
+      }
 
     case EXPAND_OUTPUT:
       gcc_assert (mode != VOIDmode);

gcc/recog.h

@@ -186,6 +186,23 @@ skip_alternative (const char *p)
 /* Nonzero means volatile operands are recognized.  */
 extern int volatile_ok;
 
+/* RAII class for temporarily setting volatile_ok.  */
+
+class temporary_volatile_ok
+{
+public:
+  temporary_volatile_ok (int value) : save_volatile_ok (volatile_ok)
+  {
+    volatile_ok = value;
+  }
+
+  ~temporary_volatile_ok () { volatile_ok = save_volatile_ok; }
+
+private:
+  temporary_volatile_ok (const temporary_volatile_ok &);
+  int save_volatile_ok;
+};
+
 /* Set by constrain_operands to the number of the alternative that
    matched.  */
 extern int which_alternative;