PR middle-end/25724

	* dojump.c (do_jump): Call do_compare_rtx_and_jump.
	(do_jump_parts_zero_rtx): New function renamed from
	do_jump_parts_equality_rtx.  Made static.  Add a mode argument.
	(do_jump_parts_equality_rtx): New function split out from
	do_jump_parts_equality.  Old implementation renamed as above.
	Call do_jump_parts_zero_rtx if either operand is zero.
	(do_jump_parts_equality): Call do_jump_parts_equality_rtx to
	do all of the heavy lifting.
	(do_compare_rtx_and_jump): Handle multi-word comparisons by
	calling either do_jump_by_parts_greater_rtx or
	do_jump_by_parts_equality_rtx.
	* expr.h (do_jump_by_parts_equality_rtx): Remove prototype.
	* expmed.c (do_cmp_and_jump): Now multi-word optimization has
	moved to do_compare_rtx_and_jump, call it directly.
	* stmt.c (do_jump_if_equal): Remove static prototype.  Add a
	mode argument.  Call do_compare_rtx_and_jump.
	(emit_case_nodes): Update calls to do_jump_if_equal.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@110906 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 161 insertions, 146 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d68c547052c..18ea30d7b34 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,24 @@
+2006-02-12  Roger Sayle  <roger@eyesopen.com>
+
+	PR middle-end/25724
+	* dojump.c (do_jump): Call do_compare_rtx_and_jump.
+	(do_jump_parts_zero_rtx): New function renamed from
+	do_jump_parts_equality_rtx.  Made static.  Add a mode argument.
+	(do_jump_parts_equality_rtx): New function split out from
+	do_jump_parts_equality.  Old implementation renamed as above.
+	Call do_jump_parts_zero_rtx if either operand is zero.
+	(do_jump_parts_equality): Call do_jump_parts_equality_rtx to
+	do all of the heavy lifting.
+	(do_compare_rtx_and_jump): Handle multi-word comparisons by
+	calling either do_jump_by_parts_greater_rtx or
+	do_jump_by_parts_equality_rtx.
+	* expr.h (do_jump_by_parts_equality_rtx): Remove prototype.
+	* expmed.c (do_cmp_and_jump): Now multi-word optimization has
+	moved to do_compare_rtx_and_jump, call it directly.
+	* stmt.c (do_jump_if_equal): Remove static prototype.  Add a
+	mode argument.  Call do_compare_rtx_and_jump.
+	(emit_case_nodes): Update calls to do_jump_if_equal.
+
 2006-02-12  Zdenek Dvorak <dvorakz@suse.cz>
 
 	PR rtl-optimization/26225
diff --git a/gcc/dojump.c b/gcc/dojump.c
index e214091510e..86dc6f4a6c4 100644
--- a/gcc/dojump.c
+++ b/gcc/dojump.c
@@ -1,6 +1,6 @@
 /* Convert tree expression to rtl instructions, for GNU compiler.
    Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-   2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -586,38 +586,20 @@ do_jump (tree exp, rtx if_false_label, rtx if_true_label)
     normal:
       temp = expand_normal (exp);
       do_pending_stack_adjust ();
-
-      if (GET_CODE (temp) == CONST_INT
-          || (GET_CODE (temp) == CONST_DOUBLE && GET_MODE (temp) == VOIDmode)
-          || GET_CODE (temp) == LABEL_REF)
-        {
-          rtx target = temp == const0_rtx ? if_false_label : if_true_label;
-          if (target)
-            emit_jump (target);
-        }
-      else if (GET_MODE_CLASS (GET_MODE (temp)) == MODE_INT
-               && ! can_compare_p (NE, GET_MODE (temp), ccp_jump))
-        /* Note swapping the labels gives us not-equal.  */
-        do_jump_by_parts_equality_rtx (temp, if_true_label, if_false_label);
-      else
+      /* The RTL optimizers prefer comparisons against pseudos.  */
+      if (GET_CODE (temp) == SUBREG)
 	{
-	  gcc_assert (GET_MODE (temp) != VOIDmode);
-	  
-	  /* The RTL optimizers prefer comparisons against pseudos.  */
-	  if (GET_CODE (temp) == SUBREG)
-	    {
-	      /* Compare promoted variables in their promoted mode.  */
-	      if (SUBREG_PROMOTED_VAR_P (temp)
-		  && REG_P (XEXP (temp, 0)))
-		temp = XEXP (temp, 0);
-	      else
-		temp = copy_to_reg (temp);
-	    }
-	  do_compare_rtx_and_jump (temp, CONST0_RTX (GET_MODE (temp)),
-				   NE, TYPE_UNSIGNED (TREE_TYPE (exp)),
-				   GET_MODE (temp), NULL_RTX,
-				   if_false_label, if_true_label);
+	  /* Compare promoted variables in their promoted mode.  */
+	  if (SUBREG_PROMOTED_VAR_P (temp)
+	      && REG_P (XEXP (temp, 0)))
+	    temp = XEXP (temp, 0);
+	  else
+	    temp = copy_to_reg (temp);
 	}
+      do_compare_rtx_and_jump (temp, CONST0_RTX (GET_MODE (temp)),
+			       NE, TYPE_UNSIGNED (TREE_TYPE (exp)),
+			       GET_MODE (temp), NULL_RTX,
+			       if_false_label, if_true_label);
     }
 
   if (drop_through_label)
@@ -695,43 +677,17 @@ do_jump_by_parts_greater_rtx (enum machine_mode mode, int unsignedp, rtx op0,
   if (drop_through_label)
     emit_label (drop_through_label);
 }
-
-/* Given an EQ_EXPR expression EXP for values too wide to be compared
-   with one insn, test the comparison and jump to the appropriate label.  */
-
-static void
-do_jump_by_parts_equality (tree exp, rtx if_false_label, rtx if_true_label)
-{
-  rtx op0 = expand_normal (TREE_OPERAND (exp, 0));
-  rtx op1 = expand_normal (TREE_OPERAND (exp, 1));
-  enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
-  int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
-  int i;
-  rtx drop_through_label = 0;
-
-  if (! if_false_label)
-    drop_through_label = if_false_label = gen_label_rtx ();
-
-  for (i = 0; i < nwords; i++)
-    do_compare_rtx_and_jump (operand_subword_force (op0, i, mode),
-                             operand_subword_force (op1, i, mode),
-                             EQ, TYPE_UNSIGNED (TREE_TYPE (exp)),
-                             word_mode, NULL_RTX, if_false_label, NULL_RTX);
-
-  if (if_true_label)
-    emit_jump (if_true_label);
-  if (drop_through_label)
-    emit_label (drop_through_label);
-}
 
-/* Jump according to whether OP0 is 0.
-   We assume that OP0 has an integer mode that is too wide
-   for the available compare insns.  */
+/* Jump according to whether OP0 is 0.  We assume that OP0 has an integer
+   mode, MODE, that is too wide for the available compare insns.  Either
+   Either (but not both) of IF_TRUE_LABEL and IF_FALSE_LABEL may be NULL_RTX
+   to indicate drop through.  */
 
-void
-do_jump_by_parts_equality_rtx (rtx op0, rtx if_false_label, rtx if_true_label)
+static void
+do_jump_by_parts_zero_rtx (enum machine_mode mode, rtx op0,
+			   rtx if_false_label, rtx if_true_label)
 {
-  int nwords = GET_MODE_SIZE (GET_MODE (op0)) / UNITS_PER_WORD;
+  int nwords = GET_MODE_SIZE (mode) / UNITS_PER_WORD;
   rtx part;
   int i;
   rtx drop_through_label = 0;
@@ -771,6 +727,58 @@ do_jump_by_parts_equality_rtx (rtx op0, rtx if_false_label, rtx if_true_label)
   if (drop_through_label)
     emit_label (drop_through_label);
 }
+
+/* Test for the equality of two RTX expressions OP0 and OP1 in mode MODE,
+   where MODE is an integer mode too wide to be compared with one insn.
+   Either (but not both) of IF_TRUE_LABEL and IF_FALSE_LABEL may be NULL_RTX
+   to indicate drop through.  */
+
+static void
+do_jump_by_parts_equality_rtx (enum machine_mode mode, rtx op0, rtx op1,
+			       rtx if_false_label, rtx if_true_label)
+{
+  int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
+  rtx drop_through_label = 0;
+  int i;
+
+  if (op1 == const0_rtx)
+    {
+      do_jump_by_parts_zero_rtx (mode, op0, if_false_label, if_true_label);
+      return;
+    }
+  else if (op0 == const0_rtx)
+    {
+      do_jump_by_parts_zero_rtx (mode, op1, if_false_label, if_true_label);
+      return;
+    }
+
+  if (! if_false_label)
+    drop_through_label = if_false_label = gen_label_rtx ();
+
+  for (i = 0; i < nwords; i++)
+    do_compare_rtx_and_jump (operand_subword_force (op0, i, mode),
+                             operand_subword_force (op1, i, mode),
+                             EQ, 0, word_mode, NULL_RTX,
+			     if_false_label, NULL_RTX);
+
+  if (if_true_label)
+    emit_jump (if_true_label);
+  if (drop_through_label)
+    emit_label (drop_through_label);
+}
+
+/* Given an EQ_EXPR expression EXP for values too wide to be compared
+   with one insn, test the comparison and jump to the appropriate label.  */
+
+static void
+do_jump_by_parts_equality (tree exp, rtx if_false_label, rtx if_true_label)
+{
+  rtx op0 = expand_normal (TREE_OPERAND (exp, 0));
+  rtx op1 = expand_normal (TREE_OPERAND (exp, 1));
+  enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
+  do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
+				 if_true_label);
+}
 
 /* Generate code for a comparison of OP0 and OP1 with rtx code CODE.
    MODE is the machine mode of the comparison, not of the result.
@@ -886,14 +894,60 @@ do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
       unsignedp = (code == GTU || code == LTU || code == GEU || code == LEU);
     }
 
+
   if (! if_true_label)
     {
       dummy_true_label = 1;
       if_true_label = gen_label_rtx ();
     }
 
-  emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp,
-                           if_true_label);
+  if (GET_MODE_CLASS (mode) == MODE_INT
+      && ! can_compare_p (code, mode, ccp_jump))
+    {
+      switch (code)
+	{
+	case LTU:
+	  do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
+					if_false_label, if_true_label);
+	  break;
+
+	case LEU:
+	  do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
+					if_true_label, if_false_label);
+	  break;
+
+	case LT:
+	  do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
+					if_false_label, if_true_label);
+	  break;
+
+	case GT:
+	  do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
+					if_false_label, if_true_label);
+	  break;
+
+	case GE:
+	  do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
+					if_true_label, if_false_label);
+	  break;
+
+	case EQ:
+	  do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
+					 if_true_label);
+	  break;
+
+	case NE:
+	  do_jump_by_parts_equality_rtx (mode, op0, op1, if_true_label,
+					 if_false_label);
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	}
+    }
+  else
+    emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp,
+			     if_true_label);
 
   if (if_false_label)
     emit_jump (if_false_label);
diff --git a/gcc/expmed.c b/gcc/expmed.c
index a12c65d1444..7d77587e6e6 100644
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -1,7 +1,8 @@
 /* Medium-level subroutines: convert bit-field store and extract
    and shifts, multiplies and divides to rtl instructions.
    Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+   Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -5564,66 +5565,14 @@ emit_store_flag_force (rtx target, enum rtx_code code, rtx op0, rtx op1,
 }
 
 /* Perform possibly multi-word comparison and conditional jump to LABEL
-   if ARG1 OP ARG2 true where ARG1 and ARG2 are of mode MODE
-
-   The algorithm is based on the code in expr.c:do_jump.
-
-   Note that this does not perform a general comparison.  Only
-   variants generated within expmed.c are correctly handled, others
-   could be handled if needed.  */
+   if ARG1 OP ARG2 true where ARG1 and ARG2 are of mode MODE.  This is
+   now a thin wrapper around do_compare_rtx_and_jump.  */
 
 static void
 do_cmp_and_jump (rtx arg1, rtx arg2, enum rtx_code op, enum machine_mode mode,
 		 rtx label)
 {
-  /* If this mode is an integer too wide to compare properly,
-     compare word by word.  Rely on cse to optimize constant cases.  */
-
-  if (GET_MODE_CLASS (mode) == MODE_INT
-      && ! can_compare_p (op, mode, ccp_jump))
-    {
-      rtx label2 = gen_label_rtx ();
-
-      switch (op)
-	{
-	case LTU:
-	  do_jump_by_parts_greater_rtx (mode, 1, arg2, arg1, label2, label);
-	  break;
-
-	case LEU:
-	  do_jump_by_parts_greater_rtx (mode, 1, arg1, arg2, label, label2);
-	  break;
-
-	case LT:
-	  do_jump_by_parts_greater_rtx (mode, 0, arg2, arg1, label2, label);
-	  break;
-
-	case GT:
-	  do_jump_by_parts_greater_rtx (mode, 0, arg1, arg2, label2, label);
-	  break;
-
-	case GE:
-	  do_jump_by_parts_greater_rtx (mode, 0, arg2, arg1, label, label2);
-	  break;
-
-	  /* do_jump_by_parts_equality_rtx compares with zero.  Luckily
-	     that's the only equality operations we do */
-	case EQ:
-	  gcc_assert (arg2 == const0_rtx && mode == GET_MODE(arg1));
-	  do_jump_by_parts_equality_rtx (arg1, label2, label);
-	  break;
-
-	case NE:
-	  gcc_assert (arg2 == const0_rtx && mode == GET_MODE(arg1));
-	  do_jump_by_parts_equality_rtx (arg1, label, label2);
-	  break;
-
-	default:
-	  gcc_unreachable ();
-	}
-
-      emit_label (label2);
-    }
-  else
-    emit_cmp_and_jump_insns (arg1, arg2, op, NULL_RTX, mode, 0, label);
+  int unsignedp = (op == LTU || op == LEU || op == GTU || op == GEU);
+  do_compare_rtx_and_jump (arg1, arg2, op, unsignedp, mode,
+			   NULL_RTX, NULL_RTX, label);
 }
diff --git a/gcc/expr.h b/gcc/expr.h
index 2be41005942..f1cf081b195 100644
--- a/gcc/expr.h
+++ b/gcc/expr.h
@@ -1,6 +1,6 @@
 /* Definitions for code generation pass of GNU compiler.
    Copyright (C) 1987, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2005
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -743,7 +743,6 @@ extern void init_all_optabs (void);
 /* Call this to initialize an optab function entry.  */
 extern rtx init_one_libfunc (const char *);
 
-extern void do_jump_by_parts_equality_rtx (rtx, rtx, rtx);
 extern void do_jump_by_parts_greater_rtx (enum machine_mode, int, rtx, rtx,
 					  rtx, rtx);
 
diff --git a/gcc/stmt.c b/gcc/stmt.c
index 3bb4f42c2da..be192169e00 100644
--- a/gcc/stmt.c
+++ b/gcc/stmt.c
@@ -1,6 +1,6 @@
 /* Expands front end tree to back end RTL for GCC
    Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
-   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
+   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -112,7 +112,6 @@ static bool check_unique_operand_names (tree, tree);
 static char *resolve_operand_name_1 (char *, tree, tree);
 static void expand_null_return_1 (void);
 static void expand_value_return (rtx);
-static void do_jump_if_equal (rtx, rtx, rtx, int);
 static int estimate_case_costs (case_node_ptr);
 static bool lshift_cheap_p (void);
 static int case_bit_test_cmp (const void *, const void *);
@@ -2588,21 +2587,14 @@ expand_case (tree exp)
   free_temp_slots ();
 }
 
-/* Generate code to jump to LABEL if OP1 and OP2 are equal.  */
+/* Generate code to jump to LABEL if OP0 and OP1 are equal in mode MODE.  */
 
 static void
-do_jump_if_equal (rtx op1, rtx op2, rtx label, int unsignedp)
+do_jump_if_equal (enum machine_mode mode, rtx op0, rtx op1, rtx label,
+		  int unsignedp)
 {
-  if (GET_CODE (op1) == CONST_INT && GET_CODE (op2) == CONST_INT)
-    {
-      if (op1 == op2)
-	emit_jump (label);
-    }
-  else
-    emit_cmp_and_jump_insns (op1, op2, EQ, NULL_RTX,
-			     (GET_MODE (op1) == VOIDmode
-			     ? GET_MODE (op2) : GET_MODE (op1)),
-			     unsignedp, label);
+  do_compare_rtx_and_jump (op0, op1, EQ, unsignedp, mode,
+			   NULL_RTX, NULL_RTX, label);
 }
 
 /* Not all case values are encountered equally.  This function
@@ -2954,7 +2946,7 @@ emit_case_nodes (rtx index, case_node_ptr node, rtx default_label,
       /* Node is single valued.  First see if the index expression matches
 	 this node and then check our children, if any.  */
 
-      do_jump_if_equal (index,
+      do_jump_if_equal (mode, index,
 			convert_modes (mode, imode,
 				       expand_normal (node->low),
 				       unsignedp),
@@ -3007,7 +2999,7 @@ emit_case_nodes (rtx index, case_node_ptr node, rtx default_label,
 
 	      /* See if the value matches what the right hand side
 		 wants.  */
-	      do_jump_if_equal (index,
+	      do_jump_if_equal (mode, index,
 				convert_modes (mode, imode,
 					       expand_normal (node->right->low),
 					       unsignedp),
@@ -3016,7 +3008,7 @@ emit_case_nodes (rtx index, case_node_ptr node, rtx default_label,
 
 	      /* See if the value matches what the left hand side
 		 wants.  */
-	      do_jump_if_equal (index,
+	      do_jump_if_equal (mode, index,
 				convert_modes (mode, imode,
 					       expand_normal (node->left->low),
 					       unsignedp),
@@ -3082,7 +3074,7 @@ emit_case_nodes (rtx index, case_node_ptr node, rtx default_label,
 	    /* We cannot process node->right normally
 	       since we haven't ruled out the numbers less than
 	       this node's value.  So handle node->right explicitly.  */
-	    do_jump_if_equal (index,
+	    do_jump_if_equal (mode, index,
 			      convert_modes
 			      (mode, imode,
 			       expand_normal (node->right->low),
@@ -3113,7 +3105,7 @@ emit_case_nodes (rtx index, case_node_ptr node, rtx default_label,
 	    /* We cannot process node->left normally
 	       since we haven't ruled out the numbers less than
 	       this node's value.  So handle node->left explicitly.  */
-	    do_jump_if_equal (index,
+	    do_jump_if_equal (mode, index,
 			      convert_modes
 			      (mode, imode,
 			       expand_normal (node->left->low),