backport: re PR tree-optimization/61375 (ICE in int_cst_value at -O3 in tree-ssa...

2014-08-01  Thomas Preud'homme  <thomas.preudhomme@arm.com>

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

    gcc/
    PR tree-optimization/61375
    * tree-ssa-math-opts.c (find_bswap_or_nop_1): Cancel optimization if
      symbolic number cannot be represented in an unsigned HOST_WIDE_INT.
    (execute_optimize_bswap): Cancel optimization if CHAR_BIT != 8.

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

From-SVN: r213426

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7813061ec446916de4cdc01aaca2a33a22b0c32b..a7f5cbe955ab9e7522c80c3681310ffcf35a232c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2014-08-01  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+       Backport from mainline
+       2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+       PR tree-optimization/61375
+       * tree-ssa-math-opts.c (find_bswap_or_nop_1): Cancel optimization if
+       symbolic number cannot be represented in an unsigned HOST_WIDE_INT.
+       (execute_optimize_bswap): Cancel optimization if CHAR_BIT != 8.
+
 2014-08-01  Richard Biener  <rguenther@suse.de>
 
        PR tree-optimization/61964

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 675ec254df309f7726c2addb07e295d095bb7413..8e6d198a1130cfce5a3bc2d5b6a3826cdb67acad 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2014-08-01  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+       Backport from mainline
+       2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+       PR tree-optimization/61375
+       * gcc.c-torture/execute/pr61375-1.c: New test.
+
 2014-08-01  Richard Biener  <rguenther@suse.de>
 
        PR tree-optimization/61964

diff --git a/gcc/testsuite/gcc.c-torture/execute/pr61375.c b/gcc/testsuite/gcc.c-torture/execute/pr61375.c
new file mode 100644 (file)
index 0000000..6fb4693
--- /dev/null
+++ b/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 HOST_WIDE_INT (PR61375).  */
+
+__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;
+}

diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c
index d11f834455a9c9fe0101b61c63e168d378260b03..523cc3ca56355a03e0564f39c65e9baa856b2c5e 100644 (file)
--- a/gcc/tree-ssa-math-opts.c
+++ b/gcc/tree-ssa-math-opts.c
@@ -1666,6 +1666,8 @@ find_bswap_1 (gimple stmt, struct symbolic_number *n, int limit)
          size = TYPE_PRECISION (n->type);
          if (size % BITS_PER_UNIT != 0)
            return NULL_TREE;
+         if (size > HOST_BITS_PER_WIDEST_INT)
+           return NULL_TREE;
          size /= BITS_PER_UNIT;
          n->n = (sizeof (HOST_WIDEST_INT) < 8 ? 0 :
                  (unsigned HOST_WIDEST_INT)0x08070605 << 32 | 0x04030201);
@@ -1709,6 +1711,8 @@ find_bswap_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) HOST_BITS_PER_WIDEST_INT)
+             return NULL_TREE;
 
            /* Sign extension: result is dependent on the value.  */
            old_type_size = TYPE_PRECISION (n->type);
@@ -1849,7 +1853,7 @@ execute_optimize_bswap (void)
   bool changed = false;
   tree bswap16_type = NULL_TREE, bswap32_type = NULL_TREE, bswap64_type = NULL_TREE;
 
-  if (BITS_PER_UNIT != 8)
+  if (BITS_PER_UNIT != 8 || CHAR_BIT != 8)
     return 0;
 
   if (sizeof (HOST_WIDEST_INT) < 8)