PHIOPT: Move two_value_replacement to match.pd

This patch converts two_value_replacement function
into a match.pd pattern.
It is a direct translation with only one minor change,
does not check for the {0,+-1} case as that is handled
before in match.pd so there is no reason to do the extra
check for it.

OK? Bootstrapped and tested on x86_64-linux-gnu with
no regressions.

gcc/ChangeLog:

	PR tree-optimization/100958
	* tree-ssa-phiopt.cc (two_value_replacement): Remove.
	(pass_phiopt::execute): Don't call two_value_replacement.
	* match.pd (a !=/== CST1 ? CST2 : CST3): Add pattern to
	handle what two_value_replacement did.

1 files changed, 2 insertions, 155 deletions

diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index 7fc6ac1..4b43f1a 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -373,155 +373,6 @@ factor_out_conditional_conversion (edge e0, edge e1, gphi *phi,
   return newphi;
 }
 
-/* Optimize
-   # x_5 in range [cst1, cst2] where cst2 = cst1 + 1
-   if (x_5 op cstN) # where op is == or != and N is 1 or 2
-     goto bb3;
-   else
-     goto bb4;
-   bb3:
-   bb4:
-   # r_6 = PHI<cst3(2), cst4(3)> # where cst3 == cst4 + 1 or cst4 == cst3 + 1
-
-   to r_6 = x_5 + (min (cst3, cst4) - cst1) or
-   r_6 = (min (cst3, cst4) + cst1) - x_5 depending on op, N and which
-   of cst3 and cst4 is smaller.  */
-
-static bool
-two_value_replacement (basic_block cond_bb, basic_block middle_bb,
-		       edge e1, gphi *phi, tree arg0, tree arg1)
-{
-  /* Only look for adjacent integer constants.  */
-  if (!INTEGRAL_TYPE_P (TREE_TYPE (arg0))
-      || !INTEGRAL_TYPE_P (TREE_TYPE (arg1))
-      || TREE_CODE (arg0) != INTEGER_CST
-      || TREE_CODE (arg1) != INTEGER_CST
-      || (tree_int_cst_lt (arg0, arg1)
-	  ? wi::to_widest (arg0) + 1 != wi::to_widest (arg1)
-	  : wi::to_widest (arg1) + 1 != wi::to_widest (arg0)))
-    return false;
-
-  if (!empty_block_p (middle_bb))
-    return false;
-
-  gcond *stmt = as_a <gcond *> (*gsi_last_bb (cond_bb));
-  tree lhs = gimple_cond_lhs (stmt);
-  tree rhs = gimple_cond_rhs (stmt);
-
-  if (TREE_CODE (lhs) != SSA_NAME
-      || !INTEGRAL_TYPE_P (TREE_TYPE (lhs))
-      || TREE_CODE (rhs) != INTEGER_CST)
-    return false;
-
-  switch (gimple_cond_code (stmt))
-    {
-    case EQ_EXPR:
-    case NE_EXPR:
-      break;
-    default:
-      return false;
-    }
-
-  /* Defer boolean x ? 0 : {1,-1} or x ? {1,-1} : 0 to
-     match_simplify_replacement.  */
-  if (TREE_CODE (TREE_TYPE (lhs)) == BOOLEAN_TYPE
-      && (integer_zerop (arg0)
-	  || integer_zerop (arg1)
-	  || TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE
-	  || (TYPE_PRECISION (TREE_TYPE (arg0))
-	      <= TYPE_PRECISION (TREE_TYPE (lhs)))))
-    return false;
-
-  value_range r;
-  get_range_query (cfun)->range_of_expr (r, lhs);
-  if (r.undefined_p ())
-    r.set_varying (TREE_TYPE (lhs));
-  wide_int min = r.lower_bound ();
-  wide_int max = r.upper_bound ();
-
-  if (min + 1 != max
-      || (wi::to_wide (rhs) != min
-	  && wi::to_wide (rhs) != max))
-    return false;
-
-  /* We need to know which is the true edge and which is the false
-     edge so that we know when to invert the condition below.  */
-  edge true_edge, false_edge;
-  extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
-  if ((gimple_cond_code (stmt) == EQ_EXPR)
-      ^ (wi::to_wide (rhs) == max)
-      ^ (e1 == false_edge))
-    std::swap (arg0, arg1);
-
-  tree type;
-  if (TYPE_PRECISION (TREE_TYPE (lhs)) == TYPE_PRECISION (TREE_TYPE (arg0)))
-    {
-      /* Avoid performing the arithmetics in bool type which has different
-	 semantics, otherwise prefer unsigned types from the two with
-	 the same precision.  */
-      if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE
-	  || !TYPE_UNSIGNED (TREE_TYPE (arg0)))
-	type = TREE_TYPE (lhs);
-      else
-	type = TREE_TYPE (arg0);
-    }
-  else if (TYPE_PRECISION (TREE_TYPE (lhs)) > TYPE_PRECISION (TREE_TYPE (arg0)))
-    type = TREE_TYPE (lhs);
-  else
-    type = TREE_TYPE (arg0);
-
-  min = wide_int::from (min, TYPE_PRECISION (type),
-			TYPE_SIGN (TREE_TYPE (lhs)));
-  wide_int a = wide_int::from (wi::to_wide (arg0), TYPE_PRECISION (type),
-			       TYPE_SIGN (TREE_TYPE (arg0)));
-  enum tree_code code;
-  wi::overflow_type ovf;
-  if (tree_int_cst_lt (arg0, arg1))
-    {
-      code = PLUS_EXPR;
-      a -= min;
-      if (!TYPE_UNSIGNED (type))
-	{
-	  /* lhs is known to be in range [min, min+1] and we want to add a
-	     to it.  Check if that operation can overflow for those 2 values
-	     and if yes, force unsigned type.  */
-	  wi::add (min + (wi::neg_p (a) ? 0 : 1), a, SIGNED, &ovf);
-	  if (ovf)
-	    type = unsigned_type_for (type);
-	}
-    }
-  else
-    {
-      code = MINUS_EXPR;
-      a += min;
-      if (!TYPE_UNSIGNED (type))
-	{
-	  /* lhs is known to be in range [min, min+1] and we want to subtract
-	     it from a.  Check if that operation can overflow for those 2
-	     values and if yes, force unsigned type.  */
-	  wi::sub (a, min + (wi::neg_p (min) ? 0 : 1), SIGNED, &ovf);
-	  if (ovf)
-	    type = unsigned_type_for (type);
-	}
-    }
-
-  tree arg = wide_int_to_tree (type, a);
-  gimple_seq stmts = NULL;
-  lhs = gimple_convert (&stmts, type, lhs);
-  tree new_rhs;
-  if (code == PLUS_EXPR)
-    new_rhs = gimple_build (&stmts, PLUS_EXPR, type, lhs, arg);
-  else
-    new_rhs = gimple_build (&stmts, MINUS_EXPR, type, arg, lhs);
-  new_rhs = gimple_convert (&stmts, TREE_TYPE (arg0), new_rhs);
-  gimple_stmt_iterator gsi = gsi_for_stmt (stmt);
-  gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT);
-
-  replace_phi_edge_with_variable (cond_bb, e1, phi, new_rhs);
-
-  /* Note that we optimized this PHI.  */
-  return true;
-}
 
 /* Return TRUE if SEQ/OP pair should be allowed during early phiopt.
    Currently this is to allow MIN/MAX and ABS/NEGATE and constants.  */
@@ -4170,12 +4021,8 @@ pass_phiopt::execute (function *)
 	}
 
       /* Do the replacement of conditional if it can be done.  */
-      if (!early_p
-	  && !diamond_p
-	  && two_value_replacement (bb, bb1, e2, phi, arg0, arg1))
-	cfgchanged = true;
-      else if (match_simplify_replacement (bb, bb1, bb2, e1, e2, phi,
-					   arg0, arg1, early_p, diamond_p))
+      if (match_simplify_replacement (bb, bb1, bb2, e1, e2, phi,
+				      arg0, arg1, early_p, diamond_p))
 	cfgchanged = true;
       else if (!early_p
 	       && !diamond_p