[2/5] Fix more asymmetric comparison functions

From 5716669d0b88265ee610ad139a0dc4152d1c20f3 Mon Sep 17 00:00:00 2001
From: Yury Gribov <tetra2005@gmail.com>
Date: Sat, 12 Dec 2015 10:27:45 +0300
Subject: [PATCH 2/5] Fix more asymmetric comparison functions.

2015-12-17  Yury Gribov  <tetra2005@gmail.com>

	* genmodes.c (cmp_modes): Make symmetric.
	* sel-sched.c (sel_rank_for_schedule): Ditto.
	* tree-ssa-loop-im.c (sort_bbs_in_loop_postorder_cmp):
	(sort_locs_in_loop_postorder_cmp):
	(find_ref_loc_in_loop_cmp): Check invariant.
	* tree-ssa-reassoc.c (range_entry_cmp): Make symmetric.
	* tree-vect-data-refs (dr_group_sort_cmp): Ditto.
---
 gcc/genmodes.c            |  6 ++++--
 gcc/sel-sched.c           |  4 +++-
 gcc/tree-ssa-loop-im.c    | 19 +++++++++++++++----
 gcc/tree-ssa-reassoc.c    |  8 +++-----
 gcc/tree-vect-data-refs.c |  7 ++++---
 5 files changed, 29 insertions(+), 15 deletions(-)

diff --git a/gcc/genmodes.c b/gcc/genmodes.c
index 15d62a0..f78a4da 100644
--- a/gcc/genmodes.c
+++ b/gcc/genmodes.c
@@ -813,8 +813,9 @@  cmp_modes (const void *a, const void *b)
     {
       if (m->counter < n->counter)
 	return -1;
-      else
+      else if (m->counter > n->counter)
 	return 1;
+      return 0;
     }
 
   if (m->component->bytesize > n->component->bytesize)
@@ -829,8 +830,9 @@  cmp_modes (const void *a, const void *b)
 
   if (m->counter < n->counter)
     return -1;
-  else
+  else if (m->counter > n->counter)
     return 1;
+  return 0;
 }
 
 static void
diff --git a/gcc/sel-sched.c b/gcc/sel-sched.c
index aebc2d9..c6efe9b 100644
--- a/gcc/sel-sched.c
+++ b/gcc/sel-sched.c
@@ -3343,7 +3343,9 @@  sel_rank_for_schedule (const void *x, const void *y)
   tmp2_insn = EXPR_INSN_RTX (tmp2);
 
   /* Schedule debug insns as early as possible.  */
-  if (DEBUG_INSN_P (tmp_insn) && !DEBUG_INSN_P (tmp2_insn))
+  if (DEBUG_INSN_P (tmp_insn) && DEBUG_INSN_P (tmp2_insn))
+    return 0;
+  else if (DEBUG_INSN_P (tmp_insn))
     return -1;
   else if (DEBUG_INSN_P (tmp2_insn))
     return 1;
diff --git a/gcc/tree-ssa-loop-im.c b/gcc/tree-ssa-loop-im.c
index 9b1b815..b53a490 100644
--- a/gcc/tree-ssa-loop-im.c
+++ b/gcc/tree-ssa-loop-im.c
@@ -1504,7 +1504,11 @@  sort_bbs_in_loop_postorder_cmp (const void *bb1_, const void *bb2_)
   struct loop *loop2 = bb2->loop_father;
   if (loop1->num == loop2->num)
     return 0;
-  return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1;
+  gcc_assert(bb_loop_postorder[loop1->num] != bb_loop_postorder[loop2->num]);
+  if (bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num])
+    return -1;
+  else
+    return 1;
 }
 
 /* qsort sort function to sort ref locs after their loop fathers postorder.  */
@@ -1518,7 +1522,11 @@  sort_locs_in_loop_postorder_cmp (const void *loc1_, const void *loc2_)
   struct loop *loop2 = gimple_bb (loc2->stmt)->loop_father;
   if (loop1->num == loop2->num)
     return 0;
-  return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1;
+  gcc_assert(bb_loop_postorder[loop1->num] != bb_loop_postorder[loop2->num]);
+  if (bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num])
+    return -1;
+  else
+    return 1;
 }
 
 /* Gathers memory references in loops.  */
@@ -1625,8 +1633,11 @@  find_ref_loc_in_loop_cmp (const void *loop_, const void *loc_)
   if (loop->num  == loc_loop->num
       || flow_loop_nested_p (loop, loc_loop))
     return 0;
-  return (bb_loop_postorder[loop->num] < bb_loop_postorder[loc_loop->num]
-	  ? -1 : 1);
+  gcc_assert(bb_loop_postorder[loop->num] != bb_loop_postorder[loc_loop->num]);
+  if (bb_loop_postorder[loop->num] < bb_loop_postorder[loc_loop->num])
+    return -1;
+  else
+    return 1;
 }
 
 /* Iterates over all locations of REF in LOOP and its subloops calling
diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c
index e54700e..472c8b1 100644
--- a/gcc/tree-ssa-reassoc.c
+++ b/gcc/tree-ssa-reassoc.c
@@ -2018,11 +2018,9 @@  range_entry_cmp (const void *a, const void *b)
 
   if (p->idx < q->idx)
     return -1;
-  else
-    {
-      gcc_checking_assert (p->idx > q->idx);
-      return 1;
-    }
+  else if (p->idx > q->idx)
+    return 1;
+  return 0;
 }
 
 /* Helper routine of optimize_range_test.
diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
index 4c566c8..7755aaa 100644
--- a/gcc/tree-vect-data-refs.c
+++ b/gcc/tree-vect-data-refs.c
@@ -2643,9 +2643,10 @@  dr_group_sort_cmp (const void *dra_, const void *drb_)
 
   /* Then sort after DR_INIT.  In case of identical DRs sort after stmt UID.  */
   cmp = tree_int_cst_compare (DR_INIT (dra), DR_INIT (drb));
-  if (cmp == 0)
-    return gimple_uid (DR_STMT (dra)) < gimple_uid (DR_STMT (drb)) ? -1 : 1;
-  return cmp;
+  if (cmp)
+    return cmp;
+
+  return gimple_uid (DR_STMT (dra)) - gimple_uid (DR_STMT (drb));
 }
 
 /* Function vect_analyze_data_ref_accesses.
-- 
1.9.1