From: Aldy Hernandez <aldyh@redhat.com>
Date: Mon, 24 May 2021 17:57:29 +0000 (+0200)
Subject: VARYING ranges of different sizes should not be equal.
X-Git-Tag: basepoints/gcc-13~7294
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ca8cc8273c5646482eedd567288b9f8aa3fb6492;p=thirdparty%2Fgcc.git

VARYING ranges of different sizes should not be equal.

VARYING ranges are just normal ranges that span the entire domain.  Such
ranges have had end-points for a few releases now, and the fact that the
legacy code was still treating all VR_VARYING the same was an oversight.

This patch fixes the oversight to match the multi-range behavior.

gcc/ChangeLog:

	* value-range.cc (irange::legacy_equal_p): Check type when
	comparing VR_VARYING types.
	(range_tests_legacy): Test comparing VARYING ranges of different
	sizes.
---

diff --git a/gcc/value-range.cc b/gcc/value-range.cc
index 865344fcc3e7..8d7b46c0239d 100644
--- a/gcc/value-range.cc
+++ b/gcc/value-range.cc
@@ -28,6 +28,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "ssa.h"
 #include "tree-pretty-print.h"
 #include "fold-const.h"
+#include "gimple-range.h"
 
 // Here we copy between any two irange's.  The ranges can be legacy or
 // multi-ranges, and copying between any combination works correctly.
@@ -454,8 +455,10 @@ irange::legacy_equal_p (const irange &other) const
 
   if (m_kind != other.m_kind)
    return false;
-  if (m_kind == VR_UNDEFINED || m_kind == VR_VARYING)
+  if (m_kind == VR_UNDEFINED)
     return true;
+  if (m_kind == VR_VARYING)
+    return range_compatible_p (type (), other.type ());
   return (vrp_operand_equal_p (tree_lower_bound (0),
 			       other.tree_lower_bound (0))
 	  && vrp_operand_equal_p (tree_upper_bound (0),
@@ -2245,6 +2248,14 @@ range_tests_legacy ()
     copy = legacy_range;
     ASSERT_TRUE (copy.varying_p ());
   }
+
+  // VARYING of different sizes should not be equal.
+  int_range_max r0 (integer_type_node);
+  int_range_max r1 (short_integer_type_node);
+  ASSERT_TRUE (r0 != r1);
+  value_range vr0 (integer_type_node);
+  int_range_max vr1 (short_integer_type_node);
+  ASSERT_TRUE (vr0 != vr1);
 }
 
 // Simulate -fstrict-enums where the domain of a type is less than the