From 84deeb6cd58884bd794da88e4d5a6c873286383b Mon Sep 17 00:00:00 2001
From: Joshua Cao <joshcao@amazon.com>
Date: Mon, 29 Jan 2024 19:54:42 +0000
Subject: [PATCH] 8324667: fold Parse::seems_stable_comparison()

Reviewed-by: jkarthikeyan, chagedorn, xliu
---
 src/hotspot/share/opto/parse.hpp  |  3 +--
 src/hotspot/share/opto/parse2.cpp | 18 ++----------------
 2 files changed, 3 insertions(+), 18 deletions(-)

diff --git a/src/hotspot/share/opto/parse.hpp b/src/hotspot/share/opto/parse.hpp
index 40314ecc29d..d5f12c8bc81 100644
--- a/src/hotspot/share/opto/parse.hpp
+++ b/src/hotspot/share/opto/parse.hpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -564,7 +564,6 @@ class Parse : public GraphKit {
   float   branch_prediction(float &cnt, BoolTest::mask btest, int target_bci, Node* test);
   bool    seems_never_taken(float prob) const;
   bool    path_is_suitable_for_uncommon_trap(float prob) const;
-  bool    seems_stable_comparison() const;
 
   void    do_ifnull(BoolTest::mask btest, Node* c);
   void    do_if(BoolTest::mask btest, Node* c);
diff --git a/src/hotspot/share/opto/parse2.cpp b/src/hotspot/share/opto/parse2.cpp
index 32961d6c812..d43b8335ffd 100644
--- a/src/hotspot/share/opto/parse2.cpp
+++ b/src/hotspot/share/opto/parse2.cpp
@@ -1354,21 +1354,6 @@ bool Parse::seems_never_taken(float prob) const {
   return prob < PROB_MIN;
 }
 
-// True if the comparison seems to be the kind that will not change its
-// statistics from true to false.  See comments in adjust_map_after_if.
-// This question is only asked along paths which are already
-// classified as untaken (by seems_never_taken), so really,
-// if a path is never taken, its controlling comparison is
-// already acting in a stable fashion.  If the comparison
-// seems stable, we will put an expensive uncommon trap
-// on the untaken path.
-bool Parse::seems_stable_comparison() const {
-  if (C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if)) {
-    return false;
-  }
-  return true;
-}
-
 //-------------------------------repush_if_args--------------------------------
 // Push arguments of an "if" bytecode back onto the stack by adjusting _sp.
 inline int Parse::repush_if_args() {
@@ -1572,7 +1557,8 @@ bool Parse::path_is_suitable_for_uncommon_trap(float prob) const {
   if (!UseInterpreter) {
     return false;
   }
-  return (seems_never_taken(prob) && seems_stable_comparison());
+  return seems_never_taken(prob) &&
+         !C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if);
 }
 
 void Parse::maybe_add_predicate_after_if(Block* path) {