Index: gcc/doc/extend.texi
===================================================================
--- gcc/doc/extend.texi	(revision 178579)
+++ gcc/doc/extend.texi	(working copy)
@@ -6561,6 +6561,29 @@ invoke undefined behavior at runtime.  W
 accesses for vector subscription can be enabled with
 @option{-Warray-bounds}.
 
+In GNU C vector comparison is supported within standard comparison
+operators: @code{==, !=, <, <=, >, >=}. Comparison operands can be
+vector expressions of integer-type or real-type. Comparison between
+integer-type vectors and real-type vectors are not supported.  The
+result of the comparison is a vector of the same width and number of
+elements as the comparison operands with a signed integral element
+type.
+
+Vectors are compared element-wise producing 0 when comparison is false
+and -1 (constant of the appropriate type where all bits are set)
+otherwise. Consider the following example.
+
+@smallexample
+typedef int v4si __attribute__ ((vector_size (16)));
+
+v4si a = @{1,2,3,4@};
+v4si b = @{3,2,1,4@};
+v4si c;
+
+c = a >  b;     /* The result would be @{0, 0,-1, 0@}  */
+c = a == b;     /* The result would be @{0,-1, 0,-1@}  */
+@end smallexample
+
 You can declare variables and use them in function calls and returns, as
 well as in assignments and some casts.  You can specify a vector type as
 a return type for a function.  Vector types can also be used as function
Index: gcc/fold-const.c
===================================================================
--- gcc/fold-const.c	(revision 178579)
+++ gcc/fold-const.c	(working copy)
@@ -5934,7 +5934,15 @@ extract_muldiv_1 (tree t, tree c, enum t
 tree
 constant_boolean_node (bool value, tree type)
 {
-  if (type == integer_type_node)
+  if (TREE_CODE (type) == VECTOR_TYPE)
+    {
+      tree tval;
+      
+      gcc_assert (TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE);
+      tval = build_int_cst (TREE_TYPE (type), value ? -1 : 0);
+      return build_vector_from_val (type, tval);
+    }
+  else if (type == integer_type_node)
     return value ? integer_one_node : integer_zero_node;
   else if (type == boolean_type_node)
     return value ? boolean_true_node : boolean_false_node;
@@ -7670,6 +7678,16 @@ fold_unary_loc (location_t loc, enum tre
 	    return build2_loc (loc, TREE_CODE (op0), type,
 			       TREE_OPERAND (op0, 0),
 			       TREE_OPERAND (op0, 1));
+	  else if (TREE_CODE (type) == VECTOR_TYPE)
+	    {
+	      tree el_type = TREE_TYPE (type);
+	      tree op_el_type = TREE_TYPE (TREE_TYPE (op0));
+
+	      if (el_type == op_el_type)
+		return op0;
+	      else
+		build1_loc (loc, VIEW_CONVERT_EXPR, type, op0);
+	    }
 	  else if (!INTEGRAL_TYPE_P (type))
 	    return build3_loc (loc, COND_EXPR, type, op0,
 			       constant_boolean_node (true, type),
Index: gcc/testsuite/gcc.c-torture/execute/vector-compare-1.c
===================================================================
--- gcc/testsuite/gcc.c-torture/execute/vector-compare-1.c	(revision 0)
+++ gcc/testsuite/gcc.c-torture/execute/vector-compare-1.c	(revision 0)
@@ -0,0 +1,123 @@
+#define vector(elcount, type)  \
+__attribute__((vector_size((elcount)*sizeof(type)))) type
+
+#define check_compare(count, res, i0, i1, op, fmt) \
+do { \
+    int __i; \
+    for (__i = 0; __i < count; __i ++) { \
+      if ((res)[__i] != ((i0)[__i] op (i1)[__i] ? -1 : 0)) \
+	{ \
+            __builtin_printf ("%i != ((" fmt " " #op " " fmt " ? -1 : 0) ", \
+			      (res)[__i], (i0)[__i], (i1)[__i]); \
+            __builtin_abort (); \
+        } \
+    } \
+} while (0)
+
+#define test(count, v0, v1, res, fmt); \
+do { \
+    res = (v0 > v1); \
+    check_compare (count, res, v0, v1, >, fmt); \
+    res = (v0 < v1); \
+    check_compare (count, res, v0, v1, <, fmt); \
+    res = (v0 >= v1); \
+    check_compare (count, res, v0, v1, >=, fmt); \
+    res = (v0 <= v1); \
+    check_compare (count, res, v0, v1, <=, fmt); \
+    res = (v0 == v1); \
+    check_compare (count, res, v0, v1, ==, fmt); \
+    res = (v0 != v1); \
+    check_compare (count, res, v0, v1, !=, fmt); \
+} while (0)
+
+
+int main (int argc, char *argv[]) {
+#define INT  int
+    vector (4, INT) i0;
+    vector (4, INT) i1;
+    vector (4, int) ires;
+    int i;
+
+    i0 = (vector (4, INT)){argc, 1,  2,  10};
+    i1 = (vector (4, INT)){0, 3, 2, (INT)-23};    
+    test (4, i0, i1, ires, "%i");
+#undef INT
+
+#define INT unsigned int 
+    vector (4, int) ures;
+    vector (4, INT) u0;
+    vector (4, INT) u1;
+
+    u0 = (vector (4, INT)){argc, 1,  2,  10};
+    u1 = (vector (4, INT)){0, 3, 2, (INT)-23};    
+    test (4, u0, u1, ures, "%u");
+#undef INT
+
+
+#define SHORT short
+    vector (8, SHORT) s0;
+    vector (8, SHORT) s1;
+    vector (8, short) sres;
+
+    s0 = (vector (8, SHORT)){argc, 1,  2,  10,  6, 87, (SHORT)-5, 2};
+    s1 = (vector (8, SHORT)){0, 3, 2, (SHORT)-23, 12, 10, (SHORT)-2, 0};    
+    test (8, s0, s1, sres, "%i");
+#undef SHORT
+
+#define SHORT unsigned short
+    vector (8, SHORT) us0;
+    vector (8, SHORT) us1;
+    vector (8, short) usres;
+
+    us0 = (vector (8, SHORT)){argc, 1,  2,  10,  6, 87, (SHORT)-5, 2};
+    us1 = (vector (8, SHORT)){0, 3, 2, (SHORT)-23, 12, 10, (SHORT)-2, 0};    
+    test (8, us0, us1, usres, "%u");
+#undef SHORT
+
+#define CHAR signed char
+    vector (16, CHAR) c0;
+    vector (16, CHAR) c1;
+    vector (16, signed char) cres;
+
+    c0 = (vector (16, CHAR)){argc, 1,  2,  10,  6, 87, (CHAR)-5, 2, \
+                             argc, 1,  2,  10,  6, 87, (CHAR)-5, 2 };
+
+    c1 = (vector (16, CHAR)){0, 3, 2, (CHAR)-23, 12, 10, (CHAR)-2, 0, \
+                             0, 3, 2, (CHAR)-23, 12, 10, (CHAR)-2, 0};
+    test (16, c0, c1, cres, "%i");
+#undef CHAR
+
+#define CHAR unsigned char
+    vector (16, CHAR) uc0;
+    vector (16, CHAR) uc1;
+    vector (16, signed char) ucres;
+
+    uc0 = (vector (16, CHAR)){argc, 1,  2,  10,  6, 87, (CHAR)-5, 2, \
+                             argc, 1,  2,  10,  6, 87, (CHAR)-5, 2 };
+
+    uc1 = (vector (16, CHAR)){0, 3, 2, (CHAR)-23, 12, 10, (CHAR)-2, 0, \
+                             0, 3, 2, (CHAR)-23, 12, 10, (CHAR)-2, 0};
+    test (16, uc0, uc1, ucres, "%u");
+#undef CHAR
+/* Float comparison.  */
+    vector (4, float) f0;
+    vector (4, float) f1;
+    vector (4, int) ifres;
+
+    f0 = (vector (4, float)){(float)argc, 1.,  2.,  10.};
+    f1 = (vector (4, float)){0., 3., 2., (float)-23};    
+    test (4, f0, f1, ifres, "%f");
+    
+/* Double comparison.  */
+    vector (2, double) d0;
+    vector (2, double) d1;
+    vector (2, long) idres;
+
+    d0 = (vector (2, double)){(double)argc,  10.};
+    d1 = (vector (2, double)){0., (double)-23};    
+    test (2, d0, d1, idres, "%f");
+
+
+    return 0;
+}
+
Index: gcc/testsuite/gcc.c-torture/execute/vector-compare-2.c
===================================================================
--- gcc/testsuite/gcc.c-torture/execute/vector-compare-2.c	(revision 0)
+++ gcc/testsuite/gcc.c-torture/execute/vector-compare-2.c	(revision 0)
@@ -0,0 +1,27 @@
+#define vector(elcount, type)  \
+__attribute__((vector_size((elcount)*sizeof(type)))) type
+
+/* Check that constant folding in 
+   these simple cases works.  */
+vector (4, int)
+foo (vector (4, int) x)
+{
+  return   (x == x) + (x != x) + (x >  x) 
+	 + (x <  x) + (x >= x) + (x <= x);
+}
+
+int 
+main (int argc, char *argv[])
+{
+  vector (4, int) t = {argc, 2, argc, 42};
+  vector (4, int) r;
+  int i;
+
+  r = foo (t);
+
+  for (i = 0; i < 4; i++)
+    if (r[i] != -3)
+      __builtin_abort ();
+
+  return 0;
+}
Index: gcc/testsuite/gcc.dg/vector-compare-1.c
===================================================================
--- gcc/testsuite/gcc.dg/vector-compare-1.c	(revision 0)
+++ gcc/testsuite/gcc.dg/vector-compare-1.c	(revision 0)
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+#define vector(elcount, type)  \
+__attribute__((vector_size((elcount)*sizeof(type)))) type
+
+void
+foo (vector (4, int) x, vector (4, float) y)
+{
+  vector (4, int) p4;
+  vector (4, int) r4;
+  vector (4, unsigned int) q4;
+  vector (8, int) r8;
+  vector (4, float) f4;
+  
+  r4 = x > y;	    /* { dg-error "comparing vectors with different element types" } */
+  r8 = (x != p4);   /* { dg-error "incompatible types when assigning to type" } */
+  r8 == r4;	    /* { dg-error "comparing vectors with different number of elements" } */
+}
Index: gcc/testsuite/gcc.dg/vector-compare-2.c
===================================================================
--- gcc/testsuite/gcc.dg/vector-compare-2.c	(revision 0)
+++ gcc/testsuite/gcc.dg/vector-compare-2.c	(revision 0)
@@ -0,0 +1,26 @@
+/* { dg-do compile } */   
+
+/* Test if C_MAYBE_CONST are folded correctly when 
+   creating VEC_COND_EXPR.  */
+
+typedef int vec __attribute__((vector_size(16)));
+
+vec i,j;
+extern vec a, b, c;
+
+extern int p, q, z;
+extern vec foo (int);
+
+vec 
+foo (int x)
+{
+  return  foo (p ? q :z) > a;
+}
+
+vec 
+bar (int x)
+{
+  return  b > foo (p ? q :z);
+}
+
+
Index: gcc/expr.c
===================================================================
--- gcc/expr.c	(revision 178579)
+++ gcc/expr.c	(working copy)
@@ -8465,6 +8465,29 @@ expand_expr_real_2 (sepops ops, rtx targ
     case UNGE_EXPR:
     case UNEQ_EXPR:
     case LTGT_EXPR:
+      if (TREE_CODE (ops->type) == VECTOR_TYPE)
+	{
+	  enum tree_code code = ops->code;
+	  tree arg0 = ops->op0;
+	  tree arg1 = ops->op1;
+	  tree el_type = TREE_TYPE (TREE_TYPE (arg0));
+	  tree t, ifexp, if_true, if_false;
+	  
+	  el_type = build_nonstandard_integer_type 
+			(GET_MODE_BITSIZE (TYPE_MODE (el_type)), 0);
+
+	  ifexp = build2 (code, type, arg0, arg1);
+	  if_true = build_vector_from_val (type, build_int_cst (el_type, -1));
+	  if_false = build_vector_from_val (type, build_int_cst (el_type, 0));
+	  
+	  t = build3 (VEC_COND_EXPR, type, ifexp, if_true, if_false);
+            
+	  return expand_expr (t,
+			      modifier != EXPAND_STACK_PARM ? target : NULL_RTX, 
+			      tmode != VOIDmode ? tmode : mode, 
+			      modifier);
+	}
+
       temp = do_store_flag (ops,
 			    modifier != EXPAND_STACK_PARM ? target : NULL_RTX,
 			    tmode != VOIDmode ? tmode : mode);
Index: gcc/c-typeck.c
===================================================================
--- gcc/c-typeck.c	(revision 178579)
+++ gcc/c-typeck.c	(working copy)
@@ -9910,6 +9910,29 @@ build_binary_op (location_t location, en
 
     case EQ_EXPR:
     case NE_EXPR:
+      if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
+        {
+          tree intt;
+          if (TREE_TYPE (type0) != TREE_TYPE (type1))
+            {
+              error_at (location, "comparing vectors with different "
+                                  "element types");
+              return error_mark_node;
+            }
+
+          if (TYPE_VECTOR_SUBPARTS (type0) != TYPE_VECTOR_SUBPARTS (type1))
+            {
+              error_at (location, "comparing vectors with different "
+                                  "number of elements");
+              return error_mark_node;
+            }
+
+          /* Always construct signed integer vector type.  */
+          intt = c_common_type_for_size (TYPE_PRECISION (TREE_TYPE (type0)),0);
+          result_type = build_vector_type (intt, TYPE_VECTOR_SUBPARTS (type0));
+          converted = 1;
+          break;
+        }
       if (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1))
 	warning_at (location,
 		    OPT_Wfloat_equal,
@@ -10022,6 +10045,29 @@ build_binary_op (location_t location, en
     case GE_EXPR:
     case LT_EXPR:
     case GT_EXPR:
+      if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
+        {
+          tree intt;
+          if (TREE_TYPE (type0) != TREE_TYPE (type1))
+            {
+              error_at (location, "comparing vectors with different "
+                                  "element types");
+              return error_mark_node;
+            }
+
+          if (TYPE_VECTOR_SUBPARTS (type0) != TYPE_VECTOR_SUBPARTS (type1))
+            {
+              error_at (location, "comparing vectors with different "
+                                  "number of elements");
+              return error_mark_node;
+            }
+
+          /* Always construct signed integer vector type.  */
+          intt = c_common_type_for_size (TYPE_PRECISION (TREE_TYPE (type0)),0);
+          result_type = build_vector_type (intt, TYPE_VECTOR_SUBPARTS (type0));
+          converted = 1;
+          break;
+        }
       build_type = integer_type_node;
       if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
 	   || code0 == FIXED_POINT_TYPE)
@@ -10429,6 +10475,10 @@ c_objc_common_truthvalue_conversion (loc
     case FUNCTION_TYPE:
       gcc_unreachable ();
 
+    case VECTOR_TYPE:
+      error_at (location, "used vector type where scalar is required");
+      return error_mark_node;
+
     default:
       break;
     }
Index: gcc/tree-vect-generic.c
===================================================================
--- gcc/tree-vect-generic.c	(revision 178579)
+++ gcc/tree-vect-generic.c	(working copy)
@@ -35,6 +35,10 @@ along with GCC; see the file COPYING3.
 #include "expr.h"
 #include "optabs.h"
 
+
+static void expand_vector_operations_1 (gimple_stmt_iterator *);
+
+
 /* 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
@@ -125,6 +129,31 @@ do_binop (gimple_stmt_iterator *gsi, tre
   return gimplify_build2 (gsi, code, inner_type, a, b);
 }
 
+
+/* Construct expression (A[BITPOS] code B[BITPOS]) ? -1 : 0
+   
+   INNER_TYPE is the type of A and B elements
+   
+   returned expression is of signed integer type with the 
+   size equal to the size of INNER_TYPE.  */
+static tree
+do_compare (gimple_stmt_iterator *gsi, tree inner_type, tree a, tree b,
+	  tree bitpos, tree bitsize, enum tree_code code)
+{
+  tree comp_type;
+
+  a = tree_vec_extract (gsi, inner_type, a, bitsize, bitpos);
+  b = tree_vec_extract (gsi, inner_type, b, bitsize, bitpos);
+  
+  comp_type = build_nonstandard_integer_type 
+		      (GET_MODE_BITSIZE (TYPE_MODE (inner_type)), 0);
+
+  return gimplify_build3 (gsi, COND_EXPR, comp_type,
+			  fold_build2 (code, boolean_type_node, a, b),
+			  build_int_cst (comp_type, -1),
+			  build_int_cst (comp_type, 0));
+}
+
 /* Expand vector addition to scalars.  This does bit twiddling
    in order to increase parallelism:
 
@@ -333,6 +362,24 @@ uniform_vector_p (tree vec)
   return NULL_TREE;
 }
 
+/* Try to expand vector comparison expression OP0 CODE OP1 by
+   querying optab if the following expression:
+	VEC_COND_EXPR< OP0 CODE OP1, {-1,...}, {0,...}>
+   can be expanded.  */
+static tree
+expand_vector_comparison (gimple_stmt_iterator *gsi, tree type, tree op0,
+                          tree op1, enum tree_code code)
+{
+  tree t;
+  if (! expand_vec_cond_expr_p (type, TREE_TYPE (op0)))
+    t = expand_vector_piecewise (gsi, do_compare, type, 
+                    TREE_TYPE (TREE_TYPE (op0)), op0, op1, code);
+  else
+    t = NULL_TREE;
+
+  return t;
+}
+
 static tree
 expand_vector_operation (gimple_stmt_iterator *gsi, tree type, tree compute_type,
 			 gimple assign, enum tree_code code)
@@ -375,8 +422,27 @@ expand_vector_operation (gimple_stmt_ite
       case BIT_NOT_EXPR:
         return expand_vector_parallel (gsi, do_unop, type,
 		      		       gimple_assign_rhs1 (assign),
-				       NULL_TREE, code);
+        			       NULL_TREE, code);
+      case EQ_EXPR:
+      case NE_EXPR:
+      case GT_EXPR:
+      case LT_EXPR:
+      case GE_EXPR:
+      case LE_EXPR:
+      case UNEQ_EXPR:
+      case UNGT_EXPR:
+      case UNLT_EXPR:
+      case UNGE_EXPR:
+      case UNLE_EXPR:
+      case LTGT_EXPR:
+      case ORDERED_EXPR:
+      case UNORDERED_EXPR:
+	{
+	  tree rhs1 = gimple_assign_rhs1 (assign);
+	  tree rhs2 = gimple_assign_rhs2 (assign);
 
+	  return expand_vector_comparison (gsi, type, rhs1, rhs2, code);
+	}
       default:
 	break;
       }
@@ -450,11 +516,11 @@ expand_vector_operations_1 (gimple_stmt_
 
   code = gimple_assign_rhs_code (stmt);
   rhs_class = get_gimple_rhs_class (code);
+  lhs = gimple_assign_lhs (stmt);
 
   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)
@@ -598,6 +664,11 @@ expand_vector_operations_1 (gimple_stmt_
 
   gcc_assert (code != VEC_LSHIFT_EXPR && code != VEC_RSHIFT_EXPR);
   new_rhs = expand_vector_operation (gsi, type, compute_type, stmt, code);
+
+  /* Leave expression untouched for later expansion.  */
+  if (new_rhs == NULL_TREE)
+    return;
+
   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);
Index: gcc/tree-cfg.c
===================================================================
--- gcc/tree-cfg.c	(revision 178579)
+++ gcc/tree-cfg.c	(working copy)
@@ -3191,6 +3191,38 @@ verify_gimple_comparison (tree type, tre
       return true;
     }
 
+  if (TREE_CODE (type) == VECTOR_TYPE)
+    {
+      if (TREE_CODE (op0_type) != VECTOR_TYPE
+	  || TREE_CODE (op1_type) != VECTOR_TYPE)
+        {
+          error ("non-vector operands in vector comparison");
+          debug_generic_expr (op0_type);
+          debug_generic_expr (op1_type);
+          return true;
+        }
+      
+      if (!useless_type_conversion_p (op0_type, op1_type)
+	  && !useless_type_conversion_p (op1_type, op0_type))
+        {
+          error ("type mismatch in vector comparison");
+          debug_generic_expr (op0_type);
+          debug_generic_expr (op1_type);
+          return true;
+        }
+      
+      if (TYPE_VECTOR_SUBPARTS (type) != TYPE_VECTOR_SUBPARTS (op0_type)
+          && TYPE_PRECISION (TREE_TYPE (op0_type)) 
+             != TYPE_PRECISION (TREE_TYPE (type)))
+        {
+          error ("invalid vector comparison resulting type");
+          debug_generic_expr (type);
+          return true;
+        }
+        
+      return false;
+    }
+
   /* For comparisons we do not have the operations type as the
      effective type the comparison is carried out in.  Instead
      we require that either the first operand is trivially
Index: gcc/config/i386/i386.c
===================================================================
--- gcc/config/i386/i386.c	(revision 178579)
+++ gcc/config/i386/i386.c	(working copy)
@@ -18445,8 +18445,13 @@ ix86_expand_sse_movcc (rtx dest, rtx cmp
 {
   enum machine_mode mode = GET_MODE (dest);
   rtx t2, t3, x;
-
-  if (op_false == CONST0_RTX (mode))
+  
+  if (vector_all_ones_operand (op_true, GET_MODE (op_true))
+      && rtx_equal_p (op_false, CONST0_RTX (mode)))
+    {
+      emit_insn (gen_rtx_SET (VOIDmode, dest, cmp));
+    }
+  else if (op_false == CONST0_RTX (mode))
     {
       op_true = force_reg (mode, op_true);
       x = gen_rtx_AND (mode, cmp, op_true);
