re PR tree-optimization/39339 (SRA miscompilation of vte)

2009-03-04  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/39339
	* tree-sra.c (try_instantiate_multiple_fields): Make it
	no longer ICE on the above.

	* gcc.c-torture/execute/pr39339.c: New testcase.

From-SVN: r144598

gcc/ChangeLog

+2009-03-04  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/39339
+	* tree-sra.c (try_instantiate_multiple_fields): Make it
+	no longer ICE on the above.
+
 2009-03-03  Joseph Myers  <joseph@codesourcery.com>
 
 	* emit-rtl.c (adjust_address_1): Reduce offset to a signed value

gcc/testsuite/ChangeLog

+2009-03-04  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/39339
+	* gcc.c-torture/execute/pr39339.c: New testcase.
+
 2009-03-03  Joseph Myers  <joseph@codesourcery.com>
 
 	* gcc.c-torture/compile/20090303-1.c,

gcc/testsuite/gcc.c-torture/execute/pr39339.c

+struct C
+{
+  unsigned int c;
+  struct D
+  {
+    unsigned int columns : 4;
+    unsigned int fore : 9;
+    unsigned int back : 9;
+    unsigned int fragment : 1;
+    unsigned int standout : 1;
+    unsigned int underline : 1;
+    unsigned int strikethrough : 1;
+    unsigned int reverse : 1;
+    unsigned int blink : 1;
+    unsigned int half : 1;
+    unsigned int bold : 1;
+    unsigned int invisible : 1;
+    unsigned int pad : 1;
+  } attr;
+};
+
+struct A
+{
+  struct C *data;
+  unsigned int len;
+};
+
+struct B
+{
+  struct A *cells;
+  unsigned char soft_wrapped : 1;
+};
+
+struct E
+{
+  long row, col;
+  struct C defaults;
+};
+
+__attribute__ ((noinline))
+void foo (struct E *screen, unsigned int c, int columns, struct B *row)
+{
+  struct D attr;
+  long col;
+  int i;
+  col = screen->col;
+  attr = screen->defaults.attr;
+  attr.columns = columns;
+  row->cells->data[col].c = c;
+  row->cells->data[col].attr = attr;
+  col++;
+  attr.fragment = 1;
+  for (i = 1; i < columns; i++)
+    {
+      row->cells->data[col].c = c;
+      row->cells->data[col].attr = attr;
+      col++;
+    }
+}
+
+int
+main (void)
+{
+  struct E e = {.row = 5,.col = 0,.defaults =
+      {6, {-1, -1, -1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0}} };
+  struct C c[4];
+  struct A a = { c, 4 };
+  struct B b = { &a, 1 };
+  struct D d;
+  __builtin_memset (&c, 0, sizeof c);
+  foo (&e, 65, 2, &b);
+  d = e.defaults.attr;
+  d.columns = 2;
+  if (__builtin_memcmp (&d, &c[0].attr, sizeof d))
+    __builtin_abort ();
+  d.fragment = 1;
+  if (__builtin_memcmp (&d, &c[1].attr, sizeof d))
+    __builtin_abort ();
+  return 0;
+}
+

gcc/tree-sra.c

@@ -1713,16 +1713,6 @@ try_instantiate_multiple_fields (struct sra_elt *elt, tree f)
   gcc_assert (block && block->is_scalar);
 
   var = block->replacement;
-
-  if ((bit & ~alchk)
-      || (HOST_WIDE_INT)size != tree_low_cst (DECL_SIZE (var), 1))
-    {
-      block->replacement = fold_build3 (BIT_FIELD_REF,
-					TREE_TYPE (block->element), var,
-					bitsize_int (size),
-					bitsize_int (bit & ~alchk));
-    }
-
   block->in_bitfld_block = 2;
 
   /* Add the member fields to the group, such that they access
@@ -1736,12 +1726,14 @@ try_instantiate_multiple_fields (struct sra_elt *elt, tree f)
       gcc_assert (fld && fld->is_scalar && !fld->replacement);
 
       fld->replacement = fold_build3 (BIT_FIELD_REF, field_type, var,
-				      DECL_SIZE (f),
+				      bitsize_int (TYPE_PRECISION (field_type)),
 				      bitsize_int
 				      ((TREE_INT_CST_LOW (DECL_FIELD_OFFSET (f))
 					* BITS_PER_UNIT
 					+ (TREE_INT_CST_LOW
-					   (DECL_FIELD_BIT_OFFSET (f))))
+					   (DECL_FIELD_BIT_OFFSET (f)))
+					- (TREE_INT_CST_LOW
+					   (TREE_OPERAND (block->element, 2))))
 				       & ~alchk));
       fld->in_bitfld_block = 1;
     }