From ffcc6a489a09be7b10e06e9bece5fe2aa06d336d Mon Sep 17 00:00:00 2001
From: zhangyipeng <zhangyipeng7@huawei.com>
Date: Tue, 9 Mar 2021 16:58:48 +0800
Subject: [PATCH] [Backport]8193518: C2:Vector registers sometimes
 corrupted at safepoint

Reference: https://bugs.openjdk.java.net/browse/JDK-8193518


Signed-off-by: He Xuejin <hexuejin2@huawei.com>
---
 hotspot/src/share/vm/opto/compile.hpp   | 6 +++---
 hotspot/src/share/vm/opto/superword.cpp | 4 +++-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/hotspot/src/share/vm/opto/compile.hpp b/hotspot/src/share/vm/opto/compile.hpp
index fd750b10e..93fa11737 100644
--- a/hotspot/src/share/vm/opto/compile.hpp
+++ b/hotspot/src/share/vm/opto/compile.hpp
@@ -316,7 +316,7 @@ class Compile : public Phase {
   bool                  _has_unsafe_access;     // True if the method _may_ produce faults in unsafe loads or stores.
   bool                  _has_stringbuilder;     // True StringBuffers or StringBuilders are allocated
   bool                  _has_boxed_value;       // True if a boxed object is allocated
-  int                   _max_vector_size;       // Maximum size of generated vectors
+  uint                  _max_vector_size;       // Maximum size of generated vectors
   uint                  _trap_hist[trapHistLength];  // Cumulative traps
   bool                  _trap_can_recompile;    // Have we emitted a recompiling trap?
   uint                  _decompile_count;       // Cumulative decompilation counts.
@@ -581,8 +581,8 @@ class Compile : public Phase {
   void          set_has_stringbuilder(bool z)   { _has_stringbuilder = z; }
   bool              has_boxed_value() const     { return _has_boxed_value; }
   void          set_has_boxed_value(bool z)     { _has_boxed_value = z; }
-  int               max_vector_size() const     { return _max_vector_size; }
-  void          set_max_vector_size(int s)      { _max_vector_size = s; }
+  uint              max_vector_size() const     { return _max_vector_size; }
+  void          set_max_vector_size(uint s)     { _max_vector_size = s; }
   void          set_trap_count(uint r, uint c)  { assert(r < trapHistLength, "oob");        _trap_hist[r] = c; }
   uint              trap_count(uint r) const    { assert(r < trapHistLength, "oob"); return _trap_hist[r]; }
   bool              trap_can_recompile() const  { return _trap_can_recompile; }
diff --git a/hotspot/src/share/vm/opto/superword.cpp b/hotspot/src/share/vm/opto/superword.cpp
index a14210ee2..2b7e7af21 100644
--- a/hotspot/src/share/vm/opto/superword.cpp
+++ b/hotspot/src/share/vm/opto/superword.cpp
@@ -1480,7 +1480,9 @@ void SuperWord::output() {
 #endif
     }
   }
-  C->set_max_vector_size(max_vlen_in_bytes);
+  if (max_vlen_in_bytes > C->max_vector_size()) {
+    C->set_max_vector_size(max_vlen_in_bytes);
+  }
 }
 
 //------------------------------vector_opd---------------------------
-- 
2.19.0