re PR tree-optimization/61375 (ICE in int_cst_value at -O3 in tree-ssa pass when compiling a reference to an __int128 value)

2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/
    PR tree-optimization/61375
    * tree-ssa-math-opts.c (init_symbolic_number): Cancel optimization if
    symbolic number cannot be represented in an uint64_t.
    (find_bswap_or_nop_1): Likewise.

    gcc/testsuite/
    PR tree-optimization/61375
    * gcc.c-torture/execute/pr61375-1.c: New test.

From-SVN: r211604

gcc/ChangeLog

@@ -1,3 +1,10 @@
+2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR tree-optimization/61375
+	* tree-ssa-math-opts.c (init_symbolic_number): Cancel optimization if
+	symbolic number cannot be represented in an uint64_t.
+	(find_bswap_or_nop_1): Likewise.
+
 2014-06-12  Jan Hubicka  <hubicka@ucw.cz>
 
 	* symtab.c (symtab_node::reset_section): New method.

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR tree-optimization/61375
+	* gcc.c-torture/execute/pr61375-1.c: New test.
+
 2014-06-12  Jakub Jelinek  <jakub@redhat.com>
 
 	PR middle-end/61486

gcc/testsuite/gcc.c-torture/execute/pr61375.c

@@ -0,0 +1,35 @@
+#ifdef __UINT64_TYPE__
+typedef __UINT64_TYPE__ uint64_t;
+#else
+typedef unsigned long long uint64_t;
+#endif
+
+#ifndef __SIZEOF_INT128__
+#define __int128 long long
+#endif
+
+/* Some version of bswap optimization would ICE when analyzing a mask constant
+   too big for an uint64_t variable (PR210931).  */
+
+__attribute__ ((noinline, noclone)) uint64_t
+uint128_central_bitsi_ior (unsigned __int128 in1, uint64_t in2)
+{
+  __int128 mask = (__int128)0xffff << 56;
+  return ((in1 & mask) >> 56) | in2;
+}
+
+int
+main(int argc)
+{
+  __int128 in = 1;
+#ifdef __SIZEOF_INT128__
+  in <<= 64;
+#endif
+  if (sizeof (uint64_t) * __CHAR_BIT__ != 64)
+    return 0;
+  if (sizeof (unsigned __int128) * __CHAR_BIT__ != 128)
+    return 0;
+  if (uint128_central_bitsi_ior (in, 2) != 0x102)
+    __builtin_abort ();
+  return 0;
+}

gcc/tree-ssa-math-opts.c

@@ -1725,6 +1725,8 @@ init_symbolic_number (struct symbolic_number *n, tree src)
   if (size % BITS_PER_UNIT != 0)
     return false;
   size /= BITS_PER_UNIT;
+  if (size > (int)sizeof (uint64_t))
+    return false;
   n->range = size;
   n->n = CMPNOP;
 
@@ -1894,6 +1896,8 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit)
 	    type_size = TYPE_PRECISION (type);
 	    if (type_size % BITS_PER_UNIT != 0)
 	      return NULL_TREE;
+	    if (type_size > (int)sizeof (uint64_t) * 8)
+	      return NULL_TREE;
 
 	    /* Sign extension: result is dependent on the value.  */
 	    old_type_size = TYPE_PRECISION (n->type);