tree-ssa.h: New.

	* tree-ssa.h: New.  Move content from tree-flow.h and
	tree-flow-inline.h.
	* tree-flow.h (_edge_var_map, edge_var_map_vector): Move to tree-ssa.h.
	Move prototypes belonging to tree-ssa.c.
	* tree-flow-inline.h (redirect_edge_var_map_def, 
	redirect_edge_var_map_result, redirect_edge_var_map_location): Move to
	tree-ssa.h.
	* gimple.h: Adjust prototypes.
	* tree-ssa.c (useless_type_conversion_p, types_compatible_p): Move to...
	* gimple.c (useless_type_conversion_p, types_compatible_p):  Here.
	* tree.h: Move prototype to tree-ssa.h.
	* gengtype.c (open_base_files): Replace tree-flow.h with tree-ssa.h.
	* Makefile.in: (TREE_SSA_H, TREE_FLOW_H): Adjust dependencies.
	* alias.c, asan.c, builtins.c, calls.c, cfgexpand.c, cfghooks.c,
	cfgloop.c, cfgloopmanip.c, cgraph.c, cgraphbuild.c, cgraphclones.c,
	cgraphunit.c, dse.c, except.c, expr.c, final.c, fold-const.c,
	ggc-page.c, gimple-fold.c, gimple-iterator.c, gimple-low.c,
	gimple-pretty-print.c, gimple-ssa-strength-reduction.c,
	gimple-streamer-in.c, gimple-streamer-out.c, gimple.c, gimplify.c,
	graphite-blocking.c, graphite-clast-to-gimple.c, graphite-dependences.c,
	graphite-interchange.c, graphite-optimize-isl.c, graphite-poly.c,
	graphite-scop-detection.c, graphite-sese-to-poly.c, graphite.c,
	ipa-cp.c, ipa-inline-analysis.c, ipa-inline-transform.c, ipa-inline.c,
	ipa-prop.c, ipa-pure-const.c, ipa-reference.c, ipa-split.c, ipa-utils.c,
	loop-init.c, lto-cgraph.c, lto-section-in.c, lto-section-out.c,
	lto-streamer-in.c, lto-streamer-out.c, lto-streamer.c, omp-low.c,
	passes.c, predict.c, print-tree.c, profile.c, sese.c, targhooks.c,
	tracer.c, trans-mem.c, tree-call-cdce.c, tree-cfg.c, tree-cfgcleanup.c,
	tree-chrec.c, tree-complex.c, tree-data-ref.c, tree-dfa.c, tree-eh.c,
	tree-emutls.c, tree-if-conv.c, tree-inline.c, tree-into-ssa.c,
	tree-loop-distribution.c, tree-mudflap.c, tree-nested.c, tree-nrv.c,
	tree-object-size.c, tree-optimize.c, tree-outof-ssa.c, tree-parloops.c,
	tree-phinodes.c, tree-predcom.c, tree-pretty-print.c, tree-profile.c,
	tree-scalar-evolution.c, tree-sra.c, tree-ssa*.c, tree-stdarg.c,
	tree-streamer-in.c, tree-switch-conversion.c, tree-tailcall.c,
	tree-vect-data-refs.c, tree-vect-generic.c, tree-vect-loop-manip.c,
	tree-vect-loop.c, tree-vect-patterns.c, tree-vect-slp.c,
	tree-vect-stmts.c, tree-vectorizer.c, tree-vrp.c, tsan.c,
	value-prof.c, var-tracking.c,
	varpool.c, vtable-verify.c: Replace tree-flow.h with tree-ssa.h

From-SVN: r202523

1 files changed, 257 insertions, 1 deletions

diff --git a/gcc/gimple.c b/gcc/gimple.c
index 4dbcdda..59fcf43 100644
--- a/gcc/gimple.c
+++ b/gcc/gimple.c
@@ -30,7 +30,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "basic-block.h"
 #include "gimple.h"
 #include "diagnostic.h"
-#include "tree-flow.h"
+#include "tree-ssa.h"
 #include "value-prof.h"
 #include "flags.h"
 #include "alias.h"
@@ -4324,4 +4324,260 @@ build_type_cast (tree to_type, gimple op, enum ssa_mode mode)
   return build_type_cast (to_type, gimple_assign_lhs (op), mode);
 }
 
+
+/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a
+   useless type conversion, otherwise return false.
+
+   This function implicitly defines the middle-end type system.  With
+   the notion of 'a < b' meaning that useless_type_conversion_p (a, b)
+   holds and 'a > b' meaning that useless_type_conversion_p (b, a) holds,
+   the following invariants shall be fulfilled:
+
+     1) useless_type_conversion_p is transitive.
+	If a < b and b < c then a < c.
+
+     2) useless_type_conversion_p is not symmetric.
+	From a < b does not follow a > b.
+
+     3) Types define the available set of operations applicable to values.
+	A type conversion is useless if the operations for the target type
+	is a subset of the operations for the source type.  For example
+	casts to void* are useless, casts from void* are not (void* can't
+	be dereferenced or offsetted, but copied, hence its set of operations
+	is a strict subset of that of all other data pointer types).  Casts
+	to const T* are useless (can't be written to), casts from const T*
+	to T* are not.  */
+
+bool
+useless_type_conversion_p (tree outer_type, tree inner_type)
+{
+  /* Do the following before stripping toplevel qualifiers.  */
+  if (POINTER_TYPE_P (inner_type)
+      && POINTER_TYPE_P (outer_type))
+    {
+      /* Do not lose casts between pointers to different address spaces.  */
+      if (TYPE_ADDR_SPACE (TREE_TYPE (outer_type))
+	  != TYPE_ADDR_SPACE (TREE_TYPE (inner_type)))
+	return false;
+    }
+
+  /* From now on qualifiers on value types do not matter.  */
+  inner_type = TYPE_MAIN_VARIANT (inner_type);
+  outer_type = TYPE_MAIN_VARIANT (outer_type);
+
+  if (inner_type == outer_type)
+    return true;
+
+  /* If we know the canonical types, compare them.  */
+  if (TYPE_CANONICAL (inner_type)
+      && TYPE_CANONICAL (inner_type) == TYPE_CANONICAL (outer_type))
+    return true;
+
+  /* Changes in machine mode are never useless conversions unless we
+     deal with aggregate types in which case we defer to later checks.  */
+  if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type)
+      && !AGGREGATE_TYPE_P (inner_type))
+    return false;
+
+  /* If both the inner and outer types are integral types, then the
+     conversion is not necessary if they have the same mode and
+     signedness and precision, and both or neither are boolean.  */
+  if (INTEGRAL_TYPE_P (inner_type)
+      && INTEGRAL_TYPE_P (outer_type))
+    {
+      /* Preserve changes in signedness or precision.  */
+      if (TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
+	  || TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
+	return false;
+
+      /* Preserve conversions to/from BOOLEAN_TYPE if types are not
+	 of precision one.  */
+      if (((TREE_CODE (inner_type) == BOOLEAN_TYPE)
+	   != (TREE_CODE (outer_type) == BOOLEAN_TYPE))
+	  && TYPE_PRECISION (outer_type) != 1)
+	return false;
+
+      /* We don't need to preserve changes in the types minimum or
+	 maximum value in general as these do not generate code
+	 unless the types precisions are different.  */
+      return true;
+    }
+
+  /* Scalar floating point types with the same mode are compatible.  */
+  else if (SCALAR_FLOAT_TYPE_P (inner_type)
+	   && SCALAR_FLOAT_TYPE_P (outer_type))
+    return true;
+
+  /* Fixed point types with the same mode are compatible.  */
+  else if (FIXED_POINT_TYPE_P (inner_type)
+	   && FIXED_POINT_TYPE_P (outer_type))
+    return true;
+
+  /* We need to take special care recursing to pointed-to types.  */
+  else if (POINTER_TYPE_P (inner_type)
+	   && POINTER_TYPE_P (outer_type))
+    {
+      /* Do not lose casts to function pointer types.  */
+      if ((TREE_CODE (TREE_TYPE (outer_type)) == FUNCTION_TYPE
+	   || TREE_CODE (TREE_TYPE (outer_type)) == METHOD_TYPE)
+	  && !(TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE
+	       || TREE_CODE (TREE_TYPE (inner_type)) == METHOD_TYPE))
+	return false;
+
+      /* We do not care for const qualification of the pointed-to types
+	 as const qualification has no semantic value to the middle-end.  */
+
+      /* Otherwise pointers/references are equivalent.  */
+      return true;
+    }
+
+  /* Recurse for complex types.  */
+  else if (TREE_CODE (inner_type) == COMPLEX_TYPE
+	   && TREE_CODE (outer_type) == COMPLEX_TYPE)
+    return useless_type_conversion_p (TREE_TYPE (outer_type),
+				      TREE_TYPE (inner_type));
+
+  /* Recurse for vector types with the same number of subparts.  */
+  else if (TREE_CODE (inner_type) == VECTOR_TYPE
+	   && TREE_CODE (outer_type) == VECTOR_TYPE
+	   && TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type))
+    return useless_type_conversion_p (TREE_TYPE (outer_type),
+				      TREE_TYPE (inner_type));
+
+  else if (TREE_CODE (inner_type) == ARRAY_TYPE
+	   && TREE_CODE (outer_type) == ARRAY_TYPE)
+    {
+      /* Preserve string attributes.  */
+      if (TYPE_STRING_FLAG (inner_type) != TYPE_STRING_FLAG (outer_type))
+	return false;
+
+      /* Conversions from array types with unknown extent to
+	 array types with known extent are not useless.  */
+      if (!TYPE_DOMAIN (inner_type)
+	  && TYPE_DOMAIN (outer_type))
+	return false;
+
+      /* Nor are conversions from array types with non-constant size to
+         array types with constant size or to different size.  */
+      if (TYPE_SIZE (outer_type)
+	  && TREE_CODE (TYPE_SIZE (outer_type)) == INTEGER_CST
+	  && (!TYPE_SIZE (inner_type)
+	      || TREE_CODE (TYPE_SIZE (inner_type)) != INTEGER_CST
+	      || !tree_int_cst_equal (TYPE_SIZE (outer_type),
+				      TYPE_SIZE (inner_type))))
+	return false;
+
+      /* Check conversions between arrays with partially known extents.
+	 If the array min/max values are constant they have to match.
+	 Otherwise allow conversions to unknown and variable extents.
+	 In particular this declares conversions that may change the
+	 mode to BLKmode as useless.  */
+      if (TYPE_DOMAIN (inner_type)
+	  && TYPE_DOMAIN (outer_type)
+	  && TYPE_DOMAIN (inner_type) != TYPE_DOMAIN (outer_type))
+	{
+	  tree inner_min = TYPE_MIN_VALUE (TYPE_DOMAIN (inner_type));
+	  tree outer_min = TYPE_MIN_VALUE (TYPE_DOMAIN (outer_type));
+	  tree inner_max = TYPE_MAX_VALUE (TYPE_DOMAIN (inner_type));
+	  tree outer_max = TYPE_MAX_VALUE (TYPE_DOMAIN (outer_type));
+
+	  /* After gimplification a variable min/max value carries no
+	     additional information compared to a NULL value.  All that
+	     matters has been lowered to be part of the IL.  */
+	  if (inner_min && TREE_CODE (inner_min) != INTEGER_CST)
+	    inner_min = NULL_TREE;
+	  if (outer_min && TREE_CODE (outer_min) != INTEGER_CST)
+	    outer_min = NULL_TREE;
+	  if (inner_max && TREE_CODE (inner_max) != INTEGER_CST)
+	    inner_max = NULL_TREE;
+	  if (outer_max && TREE_CODE (outer_max) != INTEGER_CST)
+	    outer_max = NULL_TREE;
+
+	  /* Conversions NULL / variable <- cst are useless, but not
+	     the other way around.  */
+	  if (outer_min
+	      && (!inner_min
+		  || !tree_int_cst_equal (inner_min, outer_min)))
+	    return false;
+	  if (outer_max
+	      && (!inner_max
+		  || !tree_int_cst_equal (inner_max, outer_max)))
+	    return false;
+	}
+
+      /* Recurse on the element check.  */
+      return useless_type_conversion_p (TREE_TYPE (outer_type),
+					TREE_TYPE (inner_type));
+    }
+
+  else if ((TREE_CODE (inner_type) == FUNCTION_TYPE
+	    || TREE_CODE (inner_type) == METHOD_TYPE)
+	   && TREE_CODE (inner_type) == TREE_CODE (outer_type))
+    {
+      tree outer_parm, inner_parm;
+
+      /* If the return types are not compatible bail out.  */
+      if (!useless_type_conversion_p (TREE_TYPE (outer_type),
+				      TREE_TYPE (inner_type)))
+	return false;
+
+      /* Method types should belong to a compatible base class.  */
+      if (TREE_CODE (inner_type) == METHOD_TYPE
+	  && !useless_type_conversion_p (TYPE_METHOD_BASETYPE (outer_type),
+					 TYPE_METHOD_BASETYPE (inner_type)))
+	return false;
+
+      /* A conversion to an unprototyped argument list is ok.  */
+      if (!prototype_p (outer_type))
+	return true;
+
+      /* If the unqualified argument types are compatible the conversion
+	 is useless.  */
+      if (TYPE_ARG_TYPES (outer_type) == TYPE_ARG_TYPES (inner_type))
+	return true;
+
+      for (outer_parm = TYPE_ARG_TYPES (outer_type),
+	   inner_parm = TYPE_ARG_TYPES (inner_type);
+	   outer_parm && inner_parm;
+	   outer_parm = TREE_CHAIN (outer_parm),
+	   inner_parm = TREE_CHAIN (inner_parm))
+	if (!useless_type_conversion_p
+	       (TYPE_MAIN_VARIANT (TREE_VALUE (outer_parm)),
+		TYPE_MAIN_VARIANT (TREE_VALUE (inner_parm))))
+	  return false;
+
+      /* If there is a mismatch in the number of arguments the functions
+	 are not compatible.  */
+      if (outer_parm || inner_parm)
+	return false;
+
+      /* Defer to the target if necessary.  */
+      if (TYPE_ATTRIBUTES (inner_type) || TYPE_ATTRIBUTES (outer_type))
+	return comp_type_attributes (outer_type, inner_type) != 0;
+
+      return true;
+    }
+
+  /* For aggregates we rely on TYPE_CANONICAL exclusively and require
+     explicit conversions for types involving to be structurally
+     compared types.  */
+  else if (AGGREGATE_TYPE_P (inner_type)
+	   && TREE_CODE (inner_type) == TREE_CODE (outer_type))
+    return false;
+
+  return false;
+}
+
+/* Return true if a conversion from either type of TYPE1 and TYPE2
+   to the other is not required.  Otherwise return false.  */
+
+bool
+types_compatible_p (tree type1, tree type2)
+{
+  return (type1 == type2
+	  || (useless_type_conversion_p (type1, type2)
+	      && useless_type_conversion_p (type2, type1)));
+}
+
+
 #include "gt-gimple.h"