Add gcc-4.6. Synced to @180989

Change-Id: Ie3676586e1d8e3c8cd9f07d022f450d05fa08439
svn://gcc.gnu.org/svn/gcc/branches/google/gcc-4_6-mobile

1 files changed, 688 insertions, 0 deletions

diff --git a/gcc-4.6/gcc/tree-vect-generic.c b/gcc-4.6/gcc/tree-vect-generic.c
new file mode 100644
index 000000000..fce1fc7e1
--- /dev/null
+++ b/gcc-4.6/gcc/tree-vect-generic.c
@@ -0,0 +1,688 @@
+/* Lower vector operations to scalar operations.
+   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
+   Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3, or (at your option) any
+later version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tree.h"
+#include "tm.h"
+#include "langhooks.h"
+#include "tree-flow.h"
+#include "gimple.h"
+#include "tree-iterator.h"
+#include "tree-pass.h"
+#include "flags.h"
+#include "ggc.h"
+
+/* Need to include rtl.h, expr.h, etc. for optabs.  */
+#include "expr.h"
+#include "optabs.h"
+
+/* Build a constant of type TYPE, made of VALUE's bits replicated
+   every TYPE_SIZE (INNER_TYPE) bits to fit TYPE's precision.  */
+static tree
+build_replicated_const (tree type, tree inner_type, HOST_WIDE_INT value)
+{
+  int width = tree_low_cst (TYPE_SIZE (inner_type), 1);
+  int n = HOST_BITS_PER_WIDE_INT / width;
+  unsigned HOST_WIDE_INT low, high, mask;
+  tree ret;
+
+  gcc_assert (n);
+
+  if (width == HOST_BITS_PER_WIDE_INT)
+    low = value;
+  else
+    {
+      mask = ((HOST_WIDE_INT)1 << width) - 1;
+      low = (unsigned HOST_WIDE_INT) ~0 / mask * (value & mask);
+    }
+
+  if (TYPE_PRECISION (type) < HOST_BITS_PER_WIDE_INT)
+    low &= ((HOST_WIDE_INT)1 << TYPE_PRECISION (type)) - 1, high = 0;
+  else if (TYPE_PRECISION (type) == HOST_BITS_PER_WIDE_INT)
+    high = 0;
+  else if (TYPE_PRECISION (type) == 2 * HOST_BITS_PER_WIDE_INT)
+    high = low;
+  else
+    gcc_unreachable ();
+
+  ret = build_int_cst_wide (type, low, high);
+  return ret;
+}
+
+static GTY(()) tree vector_inner_type;
+static GTY(()) tree vector_last_type;
+static GTY(()) int vector_last_nunits;
+
+/* Return a suitable vector types made of SUBPARTS units each of mode
+   "word_mode" (the global variable).  */
+static tree
+build_word_mode_vector_type (int nunits)
+{
+  if (!vector_inner_type)
+    vector_inner_type = lang_hooks.types.type_for_mode (word_mode, 1);
+  else if (vector_last_nunits == nunits)
+    {
+      gcc_assert (TREE_CODE (vector_last_type) == VECTOR_TYPE);
+      return vector_last_type;
+    }
+
+  /* We build a new type, but we canonicalize it nevertheless,
+     because it still saves some memory.  */
+  vector_last_nunits = nunits;
+  vector_last_type = type_hash_canon (nunits,
+				      build_vector_type (vector_inner_type,
+							 nunits));
+  return vector_last_type;
+}
+
+typedef tree (*elem_op_func) (gimple_stmt_iterator *,
+			      tree, tree, tree, tree, tree, enum tree_code);
+
+static inline tree
+tree_vec_extract (gimple_stmt_iterator *gsi, tree type,
+		  tree t, tree bitsize, tree bitpos)
+{
+  if (bitpos)
+    return gimplify_build3 (gsi, BIT_FIELD_REF, type, t, bitsize, bitpos);
+  else
+    return gimplify_build1 (gsi, VIEW_CONVERT_EXPR, type, t);
+}
+
+static tree
+do_unop (gimple_stmt_iterator *gsi, tree inner_type, tree a,
+	 tree b ATTRIBUTE_UNUSED, tree bitpos, tree bitsize,
+	 enum tree_code code)
+{
+  a = tree_vec_extract (gsi, inner_type, a, bitsize, bitpos);
+  return gimplify_build1 (gsi, code, inner_type, a);
+}
+
+static tree
+do_binop (gimple_stmt_iterator *gsi, tree inner_type, tree a, tree b,
+	  tree bitpos, tree bitsize, enum tree_code code)
+{
+  a = tree_vec_extract (gsi, inner_type, a, bitsize, bitpos);
+  b = tree_vec_extract (gsi, inner_type, b, bitsize, bitpos);
+  return gimplify_build2 (gsi, code, inner_type, a, b);
+}
+
+/* Expand vector addition to scalars.  This does bit twiddling
+   in order to increase parallelism:
+
+   a + b = (((int) a & 0x7f7f7f7f) + ((int) b & 0x7f7f7f7f)) ^
+           (a ^ b) & 0x80808080
+
+   a - b =  (((int) a | 0x80808080) - ((int) b & 0x7f7f7f7f)) ^
+            (a ^ ~b) & 0x80808080
+
+   -b = (0x80808080 - ((int) b & 0x7f7f7f7f)) ^ (~b & 0x80808080)
+
+   This optimization should be done only if 4 vector items or more
+   fit into a word.  */
+static tree
+do_plus_minus (gimple_stmt_iterator *gsi, tree word_type, tree a, tree b,
+	       tree bitpos ATTRIBUTE_UNUSED, tree bitsize ATTRIBUTE_UNUSED,
+	       enum tree_code code)
+{
+  tree inner_type = TREE_TYPE (TREE_TYPE (a));
+  unsigned HOST_WIDE_INT max;
+  tree low_bits, high_bits, a_low, b_low, result_low, signs;
+
+  max = GET_MODE_MASK (TYPE_MODE (inner_type));
+  low_bits = build_replicated_const (word_type, inner_type, max >> 1);
+  high_bits = build_replicated_const (word_type, inner_type, max & ~(max >> 1));
+
+  a = tree_vec_extract (gsi, word_type, a, bitsize, bitpos);
+  b = tree_vec_extract (gsi, word_type, b, bitsize, bitpos);
+
+  signs = gimplify_build2 (gsi, BIT_XOR_EXPR, word_type, a, b);
+  b_low = gimplify_build2 (gsi, BIT_AND_EXPR, word_type, b, low_bits);
+  if (code == PLUS_EXPR)
+    a_low = gimplify_build2 (gsi, BIT_AND_EXPR, word_type, a, low_bits);
+  else
+    {
+      a_low = gimplify_build2 (gsi, BIT_IOR_EXPR, word_type, a, high_bits);
+      signs = gimplify_build1 (gsi, BIT_NOT_EXPR, word_type, signs);
+    }
+
+  signs = gimplify_build2 (gsi, BIT_AND_EXPR, word_type, signs, high_bits);
+  result_low = gimplify_build2 (gsi, code, word_type, a_low, b_low);
+  return gimplify_build2 (gsi, BIT_XOR_EXPR, word_type, result_low, signs);
+}
+
+static tree
+do_negate (gimple_stmt_iterator *gsi, tree word_type, tree b,
+	   tree unused ATTRIBUTE_UNUSED, tree bitpos ATTRIBUTE_UNUSED,
+	   tree bitsize ATTRIBUTE_UNUSED,
+	   enum tree_code code ATTRIBUTE_UNUSED)
+{
+  tree inner_type = TREE_TYPE (TREE_TYPE (b));
+  HOST_WIDE_INT max;
+  tree low_bits, high_bits, b_low, result_low, signs;
+
+  max = GET_MODE_MASK (TYPE_MODE (inner_type));
+  low_bits = build_replicated_const (word_type, inner_type, max >> 1);
+  high_bits = build_replicated_const (word_type, inner_type, max & ~(max >> 1));
+
+  b = tree_vec_extract (gsi, word_type, b, bitsize, bitpos);
+
+  b_low = gimplify_build2 (gsi, BIT_AND_EXPR, word_type, b, low_bits);
+  signs = gimplify_build1 (gsi, BIT_NOT_EXPR, word_type, b);
+  signs = gimplify_build2 (gsi, BIT_AND_EXPR, word_type, signs, high_bits);
+  result_low = gimplify_build2 (gsi, MINUS_EXPR, word_type, high_bits, b_low);
+  return gimplify_build2 (gsi, BIT_XOR_EXPR, word_type, result_low, signs);
+}
+
+/* Expand a vector operation to scalars, by using many operations
+   whose type is the vector type's inner type.  */
+static tree
+expand_vector_piecewise (gimple_stmt_iterator *gsi, elem_op_func f,
+			 tree type, tree inner_type,
+			 tree a, tree b, enum tree_code code)
+{
+  VEC(constructor_elt,gc) *v;
+  tree part_width = TYPE_SIZE (inner_type);
+  tree index = bitsize_int (0);
+  int nunits = TYPE_VECTOR_SUBPARTS (type);
+  int delta = tree_low_cst (part_width, 1)
+	      / tree_low_cst (TYPE_SIZE (TREE_TYPE (type)), 1);
+  int i;
+
+  v = VEC_alloc(constructor_elt, gc, (nunits + delta - 1) / delta);
+  for (i = 0; i < nunits;
+       i += delta, index = int_const_binop (PLUS_EXPR, index, part_width, 0))
+    {
+      tree result = f (gsi, inner_type, a, b, index, part_width, code);
+      constructor_elt *ce = VEC_quick_push (constructor_elt, v, NULL);
+      ce->index = NULL_TREE;
+      ce->value = result;
+    }
+
+  return build_constructor (type, v);
+}
+
+/* Expand a vector operation to scalars with the freedom to use
+   a scalar integer type, or to use a different size for the items
+   in the vector type.  */
+static tree
+expand_vector_parallel (gimple_stmt_iterator *gsi, elem_op_func f, tree type,
+			tree a, tree b,
+			enum tree_code code)
+{
+  tree result, compute_type;
+  enum machine_mode mode;
+  int n_words = tree_low_cst (TYPE_SIZE_UNIT (type), 1) / UNITS_PER_WORD;
+
+  /* We have three strategies.  If the type is already correct, just do
+     the operation an element at a time.  Else, if the vector is wider than
+     one word, do it a word at a time; finally, if the vector is smaller
+     than one word, do it as a scalar.  */
+  if (TYPE_MODE (TREE_TYPE (type)) == word_mode)
+     return expand_vector_piecewise (gsi, f,
+				     type, TREE_TYPE (type),
+				     a, b, code);
+  else if (n_words > 1)
+    {
+      tree word_type = build_word_mode_vector_type (n_words);
+      result = expand_vector_piecewise (gsi, f,
+				        word_type, TREE_TYPE (word_type),
+					a, b, code);
+      result = force_gimple_operand_gsi (gsi, result, true, NULL, true,
+                                         GSI_SAME_STMT);
+    }
+  else
+    {
+      /* Use a single scalar operation with a mode no wider than word_mode.  */
+      mode = mode_for_size (tree_low_cst (TYPE_SIZE (type), 1), MODE_INT, 0);
+      compute_type = lang_hooks.types.type_for_mode (mode, 1);
+      result = f (gsi, compute_type, a, b, NULL_TREE, NULL_TREE, code);
+    }
+
+  return result;
+}
+
+/* Expand a vector operation to scalars; for integer types we can use
+   special bit twiddling tricks to do the sums a word at a time, using
+   function F_PARALLEL instead of F.  These tricks are done only if
+   they can process at least four items, that is, only if the vector
+   holds at least four items and if a word can hold four items.  */
+static tree
+expand_vector_addition (gimple_stmt_iterator *gsi,
+			elem_op_func f, elem_op_func f_parallel,
+			tree type, tree a, tree b, enum tree_code code)
+{
+  int parts_per_word = UNITS_PER_WORD
+	  	       / tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (type)), 1);
+
+  if (INTEGRAL_TYPE_P (TREE_TYPE (type))
+      && parts_per_word >= 4
+      && TYPE_VECTOR_SUBPARTS (type) >= 4)
+    return expand_vector_parallel (gsi, f_parallel,
+				   type, a, b, code);
+  else
+    return expand_vector_piecewise (gsi, f,
+				    type, TREE_TYPE (type),
+				    a, b, code);
+}
+
+/* Check if vector VEC consists of all the equal elements and
+   that the number of elements corresponds to the type of VEC.
+   The function returns first element of the vector
+   or NULL_TREE if the vector is not uniform.  */
+static tree
+uniform_vector_p (tree vec)
+{
+  tree first, t, els;
+  unsigned i;
+
+  if (vec == NULL_TREE)
+    return NULL_TREE;
+
+  if (TREE_CODE (vec) == VECTOR_CST)
+    {
+      els = TREE_VECTOR_CST_ELTS (vec);
+      first = TREE_VALUE (els);
+      els = TREE_CHAIN (els);
+
+      for (t = els; t; t = TREE_CHAIN (t))
+	if (!operand_equal_p (first, TREE_VALUE (t), 0))
+	  return NULL_TREE;
+
+      return first;
+    }
+
+  else if (TREE_CODE (vec) == CONSTRUCTOR)
+    {
+      first = error_mark_node;
+
+      FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (vec), i, t)
+        {
+          if (i == 0)
+            {
+              first = t;
+              continue;
+            }
+	  if (!operand_equal_p (first, t, 0))
+	    return NULL_TREE;
+        }
+      if (i != TYPE_VECTOR_SUBPARTS (TREE_TYPE (vec)))
+	return NULL_TREE;
+      
+      return first;
+    }
+  
+  return NULL_TREE;
+}
+
+static tree
+expand_vector_operation (gimple_stmt_iterator *gsi, tree type, tree compute_type,
+			 gimple assign, enum tree_code code)
+{
+  enum machine_mode compute_mode = TYPE_MODE (compute_type);
+
+  /* If the compute mode is not a vector mode (hence we are not decomposing
+     a BLKmode vector to smaller, hardware-supported vectors), we may want
+     to expand the operations in parallel.  */
+  if (GET_MODE_CLASS (compute_mode) != MODE_VECTOR_INT
+      && GET_MODE_CLASS (compute_mode) != MODE_VECTOR_FLOAT
+      && GET_MODE_CLASS (compute_mode) != MODE_VECTOR_FRACT
+      && GET_MODE_CLASS (compute_mode) != MODE_VECTOR_UFRACT
+      && GET_MODE_CLASS (compute_mode) != MODE_VECTOR_ACCUM
+      && GET_MODE_CLASS (compute_mode) != MODE_VECTOR_UACCUM)
+    switch (code)
+      {
+      case PLUS_EXPR:
+      case MINUS_EXPR:
+        if (!TYPE_OVERFLOW_TRAPS (type))
+          return expand_vector_addition (gsi, do_binop, do_plus_minus, type,
+		      		         gimple_assign_rhs1 (assign),
+					 gimple_assign_rhs2 (assign), code);
+	break;
+
+      case NEGATE_EXPR:
+        if (!TYPE_OVERFLOW_TRAPS (type))
+          return expand_vector_addition (gsi, do_unop, do_negate, type,
+		      		         gimple_assign_rhs1 (assign),
+					 NULL_TREE, code);
+	break;
+
+      case BIT_AND_EXPR:
+      case BIT_IOR_EXPR:
+      case BIT_XOR_EXPR:
+        return expand_vector_parallel (gsi, do_binop, type,
+		      		       gimple_assign_rhs1 (assign),
+				       gimple_assign_rhs2 (assign), code);
+
+      case BIT_NOT_EXPR:
+        return expand_vector_parallel (gsi, do_unop, type,
+		      		       gimple_assign_rhs1 (assign),
+				       NULL_TREE, code);
+
+      default:
+	break;
+      }
+
+  if (TREE_CODE_CLASS (code) == tcc_unary)
+    return expand_vector_piecewise (gsi, do_unop, type, compute_type,
+				    gimple_assign_rhs1 (assign),
+				    NULL_TREE, code);
+  else
+    return expand_vector_piecewise (gsi, do_binop, type, compute_type,
+				    gimple_assign_rhs1 (assign),
+				    gimple_assign_rhs2 (assign), code);
+}
+
+/* Return a type for the widest vector mode whose components are of mode
+   INNER_MODE, or NULL_TREE if none is found.
+   SATP is true for saturating fixed-point types.  */
+
+static tree
+type_for_widest_vector_mode (enum machine_mode inner_mode, optab op, int satp)
+{
+  enum machine_mode best_mode = VOIDmode, mode;
+  int best_nunits = 0;
+
+  if (SCALAR_FLOAT_MODE_P (inner_mode))
+    mode = MIN_MODE_VECTOR_FLOAT;
+  else if (SCALAR_FRACT_MODE_P (inner_mode))
+    mode = MIN_MODE_VECTOR_FRACT;
+  else if (SCALAR_UFRACT_MODE_P (inner_mode))
+    mode = MIN_MODE_VECTOR_UFRACT;
+  else if (SCALAR_ACCUM_MODE_P (inner_mode))
+    mode = MIN_MODE_VECTOR_ACCUM;
+  else if (SCALAR_UACCUM_MODE_P (inner_mode))
+    mode = MIN_MODE_VECTOR_UACCUM;
+  else
+    mode = MIN_MODE_VECTOR_INT;
+
+  for (; mode != VOIDmode; mode = GET_MODE_WIDER_MODE (mode))
+    if (GET_MODE_INNER (mode) == inner_mode
+        && GET_MODE_NUNITS (mode) > best_nunits
+	&& optab_handler (op, mode) != CODE_FOR_nothing)
+      best_mode = mode, best_nunits = GET_MODE_NUNITS (mode);
+
+  if (best_mode == VOIDmode)
+    return NULL_TREE;
+  else
+    {
+      /* For fixed-point modes, we need to pass satp as the 2nd parameter.  */
+      if (ALL_FIXED_POINT_MODE_P (best_mode))
+	return lang_hooks.types.type_for_mode (best_mode, satp);
+
+      return lang_hooks.types.type_for_mode (best_mode, 1);
+    }
+}
+
+/* Process one statement.  If we identify a vector operation, expand it.  */
+
+static void
+expand_vector_operations_1 (gimple_stmt_iterator *gsi)
+{
+  gimple stmt = gsi_stmt (*gsi);
+  tree lhs, rhs1, rhs2 = NULL, type, compute_type;
+  enum tree_code code;
+  enum machine_mode compute_mode;
+  optab op = NULL;
+  enum gimple_rhs_class rhs_class;
+  tree new_rhs;
+
+  if (gimple_code (stmt) != GIMPLE_ASSIGN)
+    return;
+
+  code = gimple_assign_rhs_code (stmt);
+  rhs_class = get_gimple_rhs_class (code);
+
+  if (rhs_class != GIMPLE_UNARY_RHS && rhs_class != GIMPLE_BINARY_RHS)
+    return;
+
+  lhs = gimple_assign_lhs (stmt);
+  rhs1 = gimple_assign_rhs1 (stmt);
+  type = gimple_expr_type (stmt);
+  if (rhs_class == GIMPLE_BINARY_RHS)
+    rhs2 = gimple_assign_rhs2 (stmt);
+
+  if (TREE_CODE (type) != VECTOR_TYPE)
+    return;
+
+  if (code == NOP_EXPR
+      || code == FLOAT_EXPR
+      || code == FIX_TRUNC_EXPR
+      || code == VIEW_CONVERT_EXPR)
+    return;
+
+  gcc_assert (code != CONVERT_EXPR);
+
+  /* The signedness is determined from input argument.  */
+  if (code == VEC_UNPACK_FLOAT_HI_EXPR
+      || code == VEC_UNPACK_FLOAT_LO_EXPR)
+    type = TREE_TYPE (rhs1);
+
+  /* Choose between vector shift/rotate by vector and vector shift/rotate by
+     scalar */
+  if (code == LSHIFT_EXPR
+      || code == RSHIFT_EXPR
+      || code == LROTATE_EXPR
+      || code == RROTATE_EXPR)
+    {
+      bool vector_scalar_shift;
+      op = optab_for_tree_code (code, type, optab_scalar);
+      
+      /* Vector/Scalar shift is supported.  */
+      vector_scalar_shift = (op && (optab_handler (op, TYPE_MODE (type)) 
+				    != CODE_FOR_nothing));
+
+      /* If the 2nd argument is vector, we need a vector/vector shift.
+         Except all the elements in the second vector are the same.  */
+      if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (rhs2))))
+        {
+          tree first;
+          gimple def_stmt;
+
+          /* Check whether we have vector <op> {x,x,x,x} where x
+             could be a scalar variable or a constant. Transform
+             vector <op> {x,x,x,x} ==> vector <op> scalar.  */
+          if (vector_scalar_shift 
+              && ((TREE_CODE (rhs2) == VECTOR_CST
+		   && (first = uniform_vector_p (rhs2)) != NULL_TREE)
+		  || (TREE_CODE (rhs2) == SSA_NAME 
+		      && (def_stmt = SSA_NAME_DEF_STMT (rhs2))
+		      && gimple_assign_single_p (def_stmt)
+		      && (first = uniform_vector_p
+			    (gimple_assign_rhs1 (def_stmt))) != NULL_TREE)))
+            {
+              gimple_assign_set_rhs2 (stmt, first);
+              update_stmt (stmt);
+              rhs2 = first;
+            }
+          else
+            op = optab_for_tree_code (code, type, optab_vector);
+        }
+    
+      /* Try for a vector/scalar shift, and if we don't have one, see if we
+         have a vector/vector shift */
+      else if (!vector_scalar_shift)
+	{
+	  op = optab_for_tree_code (code, type, optab_vector);
+
+	  if (op && (optab_handler (op, TYPE_MODE (type)) 
+		     != CODE_FOR_nothing))
+	    {
+	      /* Transform vector <op> scalar => vector <op> {x,x,x,x}.  */
+	      int n_parts = TYPE_VECTOR_SUBPARTS (type);
+	      int part_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (type)), 1);
+	      tree part_type = lang_hooks.types.type_for_size (part_size, 1);
+	      tree vect_type = build_vector_type (part_type, n_parts);
+
+	      rhs2 = fold_convert (part_type, rhs2);
+	      rhs2 = build_vector_from_val (vect_type, rhs2);
+	      gimple_assign_set_rhs2 (stmt, rhs2);
+	      update_stmt (stmt);
+	    }
+	}
+    }
+  else
+    op = optab_for_tree_code (code, type, optab_default);
+
+  /* For widening/narrowing vector operations, the relevant type is of the
+     arguments, not the widened result.  VEC_UNPACK_FLOAT_*_EXPR is
+     calculated in the same way above.  */
+  if (code == WIDEN_SUM_EXPR
+      || code == VEC_WIDEN_MULT_HI_EXPR
+      || code == VEC_WIDEN_MULT_LO_EXPR
+      || code == VEC_UNPACK_HI_EXPR
+      || code == VEC_UNPACK_LO_EXPR
+      || code == VEC_PACK_TRUNC_EXPR
+      || code == VEC_PACK_SAT_EXPR
+      || code == VEC_PACK_FIX_TRUNC_EXPR)
+    type = TREE_TYPE (rhs1);
+
+  /* Optabs will try converting a negation into a subtraction, so
+     look for it as well.  TODO: negation of floating-point vectors
+     might be turned into an exclusive OR toggling the sign bit.  */
+  if (op == NULL
+      && code == NEGATE_EXPR
+      && INTEGRAL_TYPE_P (TREE_TYPE (type)))
+    op = optab_for_tree_code (MINUS_EXPR, type, optab_default);
+
+  /* For very wide vectors, try using a smaller vector mode.  */
+  compute_type = type;
+  if (TYPE_MODE (type) == BLKmode && op)
+    {
+      tree vector_compute_type
+        = type_for_widest_vector_mode (TYPE_MODE (TREE_TYPE (type)), op,
+				       TYPE_SATURATING (TREE_TYPE (type)));
+      if (vector_compute_type != NULL_TREE
+	  && (TYPE_VECTOR_SUBPARTS (vector_compute_type)
+	      < TYPE_VECTOR_SUBPARTS (compute_type)))
+	compute_type = vector_compute_type;
+    }
+
+  /* If we are breaking a BLKmode vector into smaller pieces,
+     type_for_widest_vector_mode has already looked into the optab,
+     so skip these checks.  */
+  if (compute_type == type)
+    {
+      compute_mode = TYPE_MODE (compute_type);
+      if ((GET_MODE_CLASS (compute_mode) == MODE_VECTOR_INT
+	   || GET_MODE_CLASS (compute_mode) == MODE_VECTOR_FLOAT
+	   || GET_MODE_CLASS (compute_mode) == MODE_VECTOR_FRACT
+	   || GET_MODE_CLASS (compute_mode) == MODE_VECTOR_UFRACT
+	   || GET_MODE_CLASS (compute_mode) == MODE_VECTOR_ACCUM
+	   || GET_MODE_CLASS (compute_mode) == MODE_VECTOR_UACCUM)
+          && op != NULL
+	  && optab_handler (op, compute_mode) != CODE_FOR_nothing)
+	return;
+      else
+	/* There is no operation in hardware, so fall back to scalars.  */
+	compute_type = TREE_TYPE (type);
+    }
+
+  gcc_assert (code != VEC_LSHIFT_EXPR && code != VEC_RSHIFT_EXPR);
+  new_rhs = expand_vector_operation (gsi, type, compute_type, stmt, code);
+  if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (new_rhs)))
+    new_rhs = gimplify_build1 (gsi, VIEW_CONVERT_EXPR, TREE_TYPE (lhs),
+                               new_rhs);
+
+  /* NOTE:  We should avoid using gimple_assign_set_rhs_from_tree. One
+     way to do it is change expand_vector_operation and its callees to
+     return a tree_code, RHS1 and RHS2 instead of a tree. */
+  gimple_assign_set_rhs_from_tree (gsi, new_rhs);
+  update_stmt (gsi_stmt (*gsi));
+}
+
+/* Use this to lower vector operations introduced by the vectorizer,
+   if it may need the bit-twiddling tricks implemented in this file.  */
+
+static bool
+gate_expand_vector_operations (void)
+{
+  return flag_tree_vectorize != 0;
+}
+
+static unsigned int
+expand_vector_operations (void)
+{
+  gimple_stmt_iterator gsi;
+  basic_block bb;
+  bool cfg_changed = false;
+
+  FOR_EACH_BB (bb)
+    {
+      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	{
+	  expand_vector_operations_1 (&gsi);
+	  /* ???  If we do not cleanup EH then we will ICE in
+	     verification.  But in reality we have created wrong-code
+	     as we did not properly transition EH info and edges to
+	     the piecewise computations.  */
+	  if (maybe_clean_eh_stmt (gsi_stmt (gsi))
+	      && gimple_purge_dead_eh_edges (bb))
+	    cfg_changed = true;
+	}
+    }
+
+  return cfg_changed ? TODO_cleanup_cfg : 0;
+}
+
+struct gimple_opt_pass pass_lower_vector =
+{
+ {
+  GIMPLE_PASS,
+  "veclower",				/* name */
+  0,					/* gate */
+  expand_vector_operations,		/* execute */
+  NULL,					/* sub */
+  NULL,					/* next */
+  0,					/* static_pass_number */
+  TV_NONE,				/* tv_id */
+  PROP_cfg,				/* properties_required */
+  0,					/* properties_provided */
+  0,					/* properties_destroyed */
+  0,					/* todo_flags_start */
+  TODO_dump_func | TODO_update_ssa	/* todo_flags_finish */
+    | TODO_verify_ssa
+    | TODO_verify_stmts | TODO_verify_flow
+ }
+};
+
+struct gimple_opt_pass pass_lower_vector_ssa =
+{
+ {
+  GIMPLE_PASS,
+  "veclower2",				/* name */
+  gate_expand_vector_operations,	/* gate */
+  expand_vector_operations,		/* execute */
+  NULL,					/* sub */
+  NULL,					/* next */
+  0,					/* static_pass_number */
+  TV_NONE,				/* tv_id */
+  PROP_cfg,				/* properties_required */
+  0,					/* properties_provided */
+  0,					/* properties_destroyed */
+  0,					/* todo_flags_start */
+  TODO_dump_func | TODO_update_ssa	/* todo_flags_finish */
+    | TODO_verify_ssa
+    | TODO_verify_stmts | TODO_verify_flow
+ }
+};
+
+#include "gt-tree-vect-generic.h"