re PR target/69264 (ICE building spidermonkey -mcpu=970 -maltivec -O3: rs6000_builtin_vectorization_cost, at config/rs6000/rs6000.c:4350)

2017-01-25  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/69264
	* target.def (vector_alignment_reachable): Improve documentation.
	* doc/tm.texi: Regenerate.
	* targhooks.c (default_builtin_vector_alignment_reachable): Simplify
	and add a comment.
	* tree-vect-data-refs.c (vect_supportable_dr_alignment): Revert
	earlier changes with respect to TYPE_USER_ALIGN.
	(vector_alignment_reachable_p): Likewise.  Improve dumping.

	* g++.dg/torture/pr69264.C: New testcase.

From-SVN: r244897

gcc/ChangeLog

@@ -1,3 +1,14 @@
+2017-01-25  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69264
+	* target.def (vector_alignment_reachable): Improve documentation.
+	* doc/tm.texi: Regenerate.
+	* targhooks.c (default_builtin_vector_alignment_reachable): Simplify
+	and add a comment.
+	* tree-vect-data-refs.c (vect_supportable_dr_alignment): Revert
+	earlier changes with respect to TYPE_USER_ALIGN.
+	(vector_alignment_reachable_p): Likewise.  Improve dumping.
+
 2016-01-25  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	PR target/79145

gcc/doc/tm.texi

@@ -5745,7 +5745,7 @@ misalignment value (@var{misalign}).
 @end deftypefn
 
 @deftypefn {Target Hook} bool TARGET_VECTORIZE_VECTOR_ALIGNMENT_REACHABLE (const_tree @var{type}, bool @var{is_packed})
-Return true if vector alignment is reachable (by peeling N iterations) for the given type.
+Return true if vector alignment is reachable (by peeling N iterations) for the given scalar type @var{type}.  @var{is_packed} is false if the scalar access using @var{type} is known to be naturally aligned.
 @end deftypefn
 
 @deftypefn {Target Hook} bool TARGET_VECTORIZE_VEC_PERM_CONST_OK (machine_mode, const unsigned char *@var{sel})

gcc/target.def

@@ -1801,10 +1801,10 @@ misalignment value (@var{misalign}).",
  default_builtin_vectorization_cost)
 
 /* Return true if vector alignment is reachable (by peeling N
-   iterations) for the given type.  */
+   iterations) for the given scalar type.  */
 DEFHOOK
 (vector_alignment_reachable,
- "Return true if vector alignment is reachable (by peeling N iterations) for the given type.",
+ "Return true if vector alignment is reachable (by peeling N iterations) for the given scalar type @var{type}.  @var{is_packed} is false if the scalar access using @var{type} is known to be naturally aligned.",
  bool, (const_tree type, bool is_packed),
  default_builtin_vector_alignment_reachable)
 

gcc/targhooks.c

@@ -1127,20 +1127,12 @@ default_vector_alignment (const_tree type)
   return align;
 }
 
+/* By default assume vectors of element TYPE require a multiple of the natural
+   alignment of TYPE.  TYPE is naturally aligned if IS_PACKED is false.  */
 bool
-default_builtin_vector_alignment_reachable (const_tree type, bool is_packed)
+default_builtin_vector_alignment_reachable (const_tree /*type*/, bool is_packed)
 {
-  if (is_packed)
-    return false;
-
-  /* Assuming that types whose size is > pointer-size are not guaranteed to be
-     naturally aligned.  */
-  if (tree_int_cst_compare (TYPE_SIZE (type), bitsize_int (POINTER_SIZE)) > 0)
-    return false;
-
-  /* Assuming that types whose size is <= pointer-size
-     are naturally aligned.  */
-  return true;
+  return ! is_packed;
 }
 
 /* By default, assume that a target supports any factor of misalignment

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2017-01-25  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69264
+	* g++.dg/torture/pr69264.C: New testcase.
+
 2016-01-25  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	PR target/79145

gcc/testsuite/g++.dg/torture/pr69264.C

@@ -0,0 +1,81 @@
+// { dg-do compile }
+// { dg-additional-options "-mcpu=970 -maltivec" { target powerpc*-*-* } }
+
+typedef union {
+    long int asBits;
+} jsval_layout;
+static jsval_layout STRING_TO_JSVAL_IMPL() {}
+
+typedef __attribute__ ((aligned(sizeof (long int)))) long int jsval;
+class Value {
+public:
+    void setString() {
+	data = STRING_TO_JSVAL_IMPL();
+    }
+    jsval_layout data;
+} __attribute__ ((aligned(8)));
+
+static Value StringValue()
+{
+  Value v;
+  v.setString();
+  return v;
+}
+
+static const jsval & Jsvalify(const Value & v)
+{
+  return (const jsval &)v;
+}
+
+static Value *Valueify(jsval *v)
+{
+  return (Value *) v;
+}
+
+struct JSObject {
+    void getQNameLocalName();
+};
+static Value IdToValue(int id)
+{
+  if (id)
+    return StringValue();
+}
+
+static jsval IdToJsval(int id)
+{
+  return Jsvalify(IdToValue(id));
+}
+
+class AutoGCRooter;
+struct JSContext {
+    AutoGCRooter *autoGCRooters;
+};
+class AutoGCRooter {
+public:
+    AutoGCRooter(JSContext *cx) {}
+};
+class AutoArrayRooter:AutoGCRooter {
+public:
+    AutoArrayRooter(JSContext *cx, Value *vec):AutoGCRooter(cx)
+    {
+      array = vec;
+      cx->autoGCRooters = this;
+    }
+    Value *array;
+};
+
+static void PutProperty(JSContext *cx, int id, jsval *vp)
+{
+  JSObject *nameobj;
+  jsval roots[3];
+  roots[1] = IdToJsval(id);
+  roots[2] = *vp;
+  AutoArrayRooter tvr(cx, Valueify(roots));
+  nameobj->getQNameLocalName();
+}
+
+void xml_defineProperty(JSContext *cx, int id, const Value *v)
+{
+  jsval tmp = Jsvalify(*v);
+  PutProperty(cx, id, &tmp);
+}

gcc/tree-vect-data-refs.c

@@ -1098,12 +1098,9 @@ vector_alignment_reachable_p (struct data_reference *dr)
       bool is_packed = not_size_aligned (DR_REF (dr));
       if (dump_enabled_p ())
 	dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
-	                 "Unknown misalignment, is_packed = %d\n",is_packed);
-      if ((TYPE_USER_ALIGN (type) && !is_packed)
-	  || targetm.vectorize.vector_alignment_reachable (type, is_packed))
-	return true;
-      else
-	return false;
+	                 "Unknown misalignment, %snaturally aligned\n",
+			 is_packed ? "not " : "");
+      return targetm.vectorize.vector_alignment_reachable (type, is_packed);
     }
 
   return true;
@@ -6153,10 +6150,8 @@ vect_supportable_dr_alignment (struct data_reference *dr,
       if (!known_alignment_for_access_p (dr))
 	is_packed = not_size_aligned (DR_REF (dr));
 
-      if ((TYPE_USER_ALIGN (type) && !is_packed)
-	  || targetm.vectorize.
-	       support_vector_misalignment (mode, type,
-					    DR_MISALIGNMENT (dr), is_packed))
+      if (targetm.vectorize.support_vector_misalignment
+	    (mode, type, DR_MISALIGNMENT (dr), is_packed))
 	/* Can't software pipeline the loads, but can at least do them.  */
 	return dr_unaligned_supported;
     }
@@ -6168,10 +6163,8 @@ vect_supportable_dr_alignment (struct data_reference *dr,
       if (!known_alignment_for_access_p (dr))
 	is_packed = not_size_aligned (DR_REF (dr));
 
-     if ((TYPE_USER_ALIGN (type) && !is_packed)
-	 || targetm.vectorize.
-	      support_vector_misalignment (mode, type,
-					   DR_MISALIGNMENT (dr), is_packed))
+     if (targetm.vectorize.support_vector_misalignment
+	   (mode, type, DR_MISALIGNMENT (dr), is_packed))
        return dr_unaligned_supported;
     }