re PR tree-optimization/24689 (operand_equal_p does not return true for some equivalent ARRAY_REF)

2007-04-12  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/24689
	PR tree-optimization/31307
	* fold-const.c (operand_equal_p): Compare INTEGER_CST array
	indices by value.
	* gimplify.c (canonicalize_addr_expr): To be consistent with
	gimplify_compound_lval only set operands two and three of
	ARRAY_REFs if they are not gimple_min_invariant.  This makes
	it never at this place.
	* tree-ssa-ccp.c (maybe_fold_offset_to_array_ref): Likewise.

	* g++.dg/tree-ssa/pr31307.C: New testcase.
	* gcc.dg/tree-ssa/pr24689.c: Likewise.

From-SVN: r123736

gcc/ChangeLog

+2007-04-12  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/24689
+	PR tree-optimization/31307
+	* fold-const.c (operand_equal_p): Compare INTEGER_CST array
+	indices by value.
+	* gimplify.c (canonicalize_addr_expr): To be consistent with
+	gimplify_compound_lval only set operands two and three of
+	ARRAY_REFs if they are not gimple_min_invariant.  This makes
+	it never at this place.
+	* tree-ssa-ccp.c (maybe_fold_offset_to_array_ref): Likewise.
+
 2007-04-11  John David Anglin  <dave.anglin@nrc-cnrc.gc.ca>
 
 	* pa.c (pa_som_asm_init_sections): Ensure that cfun->machine is not

gcc/fold-const.c

@@ -2884,9 +2884,13 @@ operand_equal_p (tree arg0, tree arg1, unsigned int flags)
 
 	case ARRAY_REF:
 	case ARRAY_RANGE_REF:
-	  /* Operands 2 and 3 may be null.  */
+	  /* Operands 2 and 3 may be null.
+	     Compare the array index by value if it is constant first as we
+	     may have different types but same value here.  */
 	  return (OP_SAME (0)
-		  && OP_SAME (1)
+		  && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
+					  TREE_OPERAND (arg1, 1))
+		      || OP_SAME (1))
 		  && OP_SAME_WITH_NULL (2)
 		  && OP_SAME_WITH_NULL (3));
 

gcc/gimplify.c

@@ -1607,9 +1607,7 @@ canonicalize_addr_expr (tree *expr_p)
   /* All checks succeeded.  Build a new node to merge the cast.  */
   *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
 		    TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
-		    TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
-		    size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
-				size_int (TYPE_ALIGN_UNIT (dctype))));
+		    NULL_TREE, NULL_TREE);
   *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
 }
 

gcc/testsuite/ChangeLog

+2007-04-12  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/24689
+	PR tree-optimization/31307
+	* g++.dg/tree-ssa/pr31307.C: New testcase.
+	* gcc.dg/tree-ssa/pr24689.c: Likewise.
+
 2007-04-12  Tobias Burnus  <burnus@net-b.de>
 
 	PR fortran/31472

gcc/testsuite/g++.dg/tree-ssa/pr31307.C

+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-optimized" } */
+
+union MY_M128
+{
+  double i;
+};
+
+struct RegFile
+{
+  MY_M128 dst[4];
+};
+
+__inline__ __attribute__((always_inline)) static void
+MEM_OPT_LOAD(MY_M128* reg, double* mem)
+{
+  reg[0].i = *mem;
+}
+
+void _ia32_movntdq (double *, double);
+
+__inline__ __attribute__((always_inline)) static void
+MEM_OPT_STORE(MY_M128* reg, double* mem)
+{
+  _ia32_movntdq ((double*)mem, (double)reg[0].i);
+}
+
+double _mm_adds_epu8 (double __A, double __B);
+
+int test(unsigned char *d)
+{ 
+  RegFile r;
+  MEM_OPT_LOAD((r.dst) , ((double*) d)); 
+  r.dst[0].i = _mm_adds_epu8(r.dst[0].i, r.dst[0].i);
+  MEM_OPT_STORE((r.dst), (double*) d);
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-not "r.dst" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */

gcc/testsuite/gcc.dg/tree-ssa/pr24689.c

+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-optimized" } */
+
+extern void bar (unsigned int);
+
+int
+foo (void)
+{
+  char buf[1] = { 3 };
+  const char *p = buf;
+  const char **q = &p;
+  unsigned int ch;
+  switch (**q)
+    {
+    case 1:  ch = 5; break;
+    default: ch = 0; break;
+    }
+
+  bar (ch);
+  return ch;
+}
+
+/* { dg-final { scan-tree-dump "return 0;" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */

gcc/tree-ssa-ccp.c

@@ -1632,9 +1632,7 @@ maybe_fold_offset_to_array_ref (tree base, tree offset, tree orig_type)
   if (!integer_zerop (elt_offset))
     idx = int_const_binop (PLUS_EXPR, idx, elt_offset, 0);
 
-  return build4 (ARRAY_REF, orig_type, base, idx, min_idx,
-		 size_int (tree_low_cst (elt_size, 1)
-			   / (TYPE_ALIGN_UNIT (elt_type))));
+  return build4 (ARRAY_REF, orig_type, base, idx, NULL_TREE, NULL_TREE);
 }