fold-const: Return corresponding integral type for OFFSET_TYPE in range_check_type...

Andrew's recent r12-1608-g2f1686ff70b25fceb04ca2ffc0a450fb682913ef change
to fail verification on various unary and binary operations with OFFSET_TYPE
revealed that e.g. switchconv happily performs multiplications and additions
in OFFSET_TYPE.

2021-06-22  Jakub Jelinek  <jakub@redhat.com>
	    Andrew Pinski  <apinski@marvell.com>

	PR tree-optimization/101162
	* fold-const.c (range_check_type): Handle OFFSET_TYPE like pointer
	types.

	* g++.dg/opt/pr101162.C: New test.

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 95673d2..0b33ee9 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -5360,7 +5360,7 @@ range_check_type (tree etype)
       else
        return NULL_TREE;
     }
-  else if (POINTER_TYPE_P (etype))
+  else if (POINTER_TYPE_P (etype) || TREE_CODE (etype) == OFFSET_TYPE)
     etype = unsigned_type_for (etype);
   return etype;
 }

diff --git a/gcc/testsuite/g++.dg/opt/pr101162.C b/gcc/testsuite/g++.dg/opt/pr101162.C
new file mode 100644 (file)
index 0000000..4032189
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/pr101162.C
@@ -0,0 +1,21 @@
+// PR tree-optimization/101162
+// { dg-do compile }
+// { dg-options "-O2" }
+
+struct A { int i1, i2, i3, i4, i5, i6; };
+
+int A::*
+foo (int i)
+{
+  switch (i)
+    {
+    case 1: return &A::i1;
+    case 2: return &A::i2;
+    case 3: return &A::i3;
+    case 4: return &A::i4;
+    case 5: return &A::i5;
+    case 6: return &A::i6;
+    }
+
+  return 0;
+}