[gcc r14-2120] Implement ipa_vr hashing.

[gcc r14-2120] Implement ipa_vr hashing.

[Aldy Hernandez]

https://gcc.gnu.org/g:15819a7df1f673357b521daef6bda3c45c2ef49c

commit r14-2120-g15819a7df1f673357b521daef6bda3c45c2ef49c
Author: Aldy Hernandez <aldyh@redhat.com>
Date:   Mon May 22 12:07:15 2023 +0200

    Implement ipa_vr hashing.
    
    Implement hashing for ipa_vr.  When all is said and done, all these
    patches incurr a 7.64% slowdown for ipa-cp, with is entirely covered by
    the similar 7% increase in this area last week.  So we get type agnostic
    ranges with "infinite" range precision close to free.
    
    There is no change in overall compilation.
    
    gcc/ChangeLog:
    
            * ipa-prop.cc (struct ipa_vr_ggc_hash_traits): Adjust for use with
            ipa_vr instead of value_range.
            (gt_pch_nx): Same.
            (gt_ggc_mx): Same.
            (ipa_get_value_range): Same.
            * value-range.cc (gt_pch_nx): Move to ipa-prop.cc and adjust for
            ipa_vr.
            (gt_ggc_mx): Same.

Diff:
---
 gcc/ipa-prop.cc    | 76 ++++++++++++++++++++++++++++++++----------------------
 gcc/value-range.cc | 15 -----------
 2 files changed, 45 insertions(+), 46 deletions(-)

diff --git a/gcc/ipa-prop.cc b/gcc/ipa-prop.cc
index b3228866129..d93234e8327 100644
--- a/gcc/ipa-prop.cc
+++ b/gcc/ipa-prop.cc
@@ -109,53 +109,53 @@ struct ipa_bit_ggc_hash_traits : public ggc_cache_remove <ipa_bits *>
 /* Hash table for avoid repeated allocations of equal ipa_bits.  */
 static GTY ((cache)) hash_table<ipa_bit_ggc_hash_traits> *ipa_bits_hash_table;
 
-/* Traits for a hash table for reusing value_ranges used for IPA.  Note that
-   the equiv bitmap is not hashed and is expected to be NULL.  */
+/* Traits for a hash table for reusing ranges.  */
 
-struct ipa_vr_ggc_hash_traits : public ggc_cache_remove <value_range *>
+struct ipa_vr_ggc_hash_traits : public ggc_cache_remove <ipa_vr *>
 {
-  typedef value_range *value_type;
-  typedef value_range *compare_type;
+  typedef ipa_vr *value_type;
+  typedef const vrange *compare_type;
   static hashval_t
-  hash (const value_range *p)
+  hash (const ipa_vr *p)
     {
-      tree min, max;
-      value_range_kind kind = get_legacy_range (*p, min, max);
-      inchash::hash hstate (kind);
-      inchash::add_expr (min, hstate);
-      inchash::add_expr (max, hstate);
+      // This never get called, except in the verification code, as
+      // ipa_get_value_range() calculates the hash itself.  This
+      // function is mostly here for completness' sake.
+      Value_Range vr;
+      p->get_vrange (vr);
+      inchash::hash hstate;
+      add_vrange (vr, hstate);
       return hstate.end ();
     }
   static bool
-  equal (const value_range *a, const value_range *b)
+  equal (const ipa_vr *a, const vrange *b)
     {
-      return (types_compatible_p (a->type (), b->type ())
-	      && *a == *b);
+      return a->equal_p (*b);
     }
   static const bool empty_zero_p = true;
   static void
-  mark_empty (value_range *&p)
+  mark_empty (ipa_vr *&p)
     {
       p = NULL;
     }
   static bool
-  is_empty (const value_range *p)
+  is_empty (const ipa_vr *p)
     {
       return p == NULL;
     }
   static bool
-  is_deleted (const value_range *p)
+  is_deleted (const ipa_vr *p)
     {
-      return p == reinterpret_cast<const value_range *> (1);
+      return p == reinterpret_cast<const ipa_vr *> (1);
     }
   static void
-  mark_deleted (value_range *&p)
+  mark_deleted (ipa_vr *&p)
     {
-      p = reinterpret_cast<value_range *> (1);
+      p = reinterpret_cast<ipa_vr *> (1);
     }
 };
 
-/* Hash table for avoid repeated allocations of equal value_ranges.  */
+/* Hash table for avoid repeated allocations of equal ranges.  */
 static GTY ((cache)) hash_table<ipa_vr_ggc_hash_traits> *ipa_vr_hash_table;
 
 /* Holders of ipa cgraph hooks: */
@@ -265,6 +265,22 @@ ipa_vr::dump (FILE *out) const
     fprintf (out, "NO RANGE");
 }
 
+// These stubs are because we use an ipa_vr in a hash_traits and
+// hash-traits.h defines an extern of gt_ggc_mx (T &) instead of
+// picking up the gt_ggc_mx (T *) version.
+void
+gt_pch_nx (ipa_vr *&x)
+{
+  return gt_pch_nx ((ipa_vr *) x);
+}
+
+void
+gt_ggc_mx (ipa_vr *&x)
+{
+  return gt_ggc_mx ((ipa_vr *) x);
+}
+
+
 /* Return true if DECL_FUNCTION_SPECIFIC_OPTIMIZATION of the decl associated
    with NODE should prevent us from analyzing it for the purposes of IPA-CP.  */
 
@@ -2284,27 +2300,25 @@ ipa_set_jfunc_bits (ipa_jump_func *jf, const widest_int &value,
   jf->bits = ipa_get_ipa_bits_for_value (value, mask);
 }
 
-/* Return a pointer to a value_range just like *TMP, but either find it in
-   ipa_vr_hash_table or allocate it in GC memory.  TMP->equiv must be NULL.  */
+/* Return a pointer to an ipa_vr just like TMP, but either find it in
+   ipa_vr_hash_table or allocate it in GC memory.  */
 
 static ipa_vr *
 ipa_get_value_range (const vrange &tmp)
 {
-  /* FIXME: Add hashing support.
-  value_range **slot = ipa_vr_hash_table->find_slot (tmp, INSERT);
+  inchash::hash hstate;
+  inchash::add_vrange (tmp, hstate);
+  hashval_t hash = hstate.end ();
+  ipa_vr **slot = ipa_vr_hash_table->find_slot_with_hash (&tmp, hash, INSERT);
   if (*slot)
     return *slot;
 
-  value_range *vr = new (ggc_alloc<value_range> ()) value_range;
-  *vr = *tmp;
-  *slot = vr;
-  */
   ipa_vr *vr = new (ggc_alloc<ipa_vr> ()) ipa_vr (tmp);
-
+  *slot = vr;
   return vr;
 }
 
-/* Assign to JF a pointer to a value_range just like TMP but either fetch a
+/* Assign to JF a pointer to a range just like TMP but either fetch a
    copy from ipa_vr_hash_table or allocate a new on in GC memory.  */
 
 static void
diff --git a/gcc/value-range.cc b/gcc/value-range.cc
index 707b1f15fd4..6f46f7c9875 100644
--- a/gcc/value-range.cc
+++ b/gcc/value-range.cc
@@ -1993,21 +1993,6 @@ gt_pch_nx (vrange *x, gt_pointer_operator op, void *cookie)
     gcc_unreachable ();
 }
 
-// ?? These stubs are for ipa-prop.cc which use a value_range in a
-// hash_traits.  hash-traits.h defines an extern of gt_ggc_mx (T &)
-// instead of picking up the gt_ggc_mx (T *) version.
-void
-gt_pch_nx (int_range<2> *&x)
-{
-  return gt_pch_nx ((irange *) x);
-}
-
-void
-gt_ggc_mx (int_range<2> *&x)
-{
-  return gt_ggc_mx ((irange *) x);
-}
-
 #define DEFINE_INT_RANGE_INSTANCE(N)					\
   template int_range<N>::int_range(tree_node *,				\
 				   const wide_int &,			\