8222670 patch review: prevent downgraded tasks from recompiling

[Liu, Xin]

hi, Severin, 

Thanks for reviewing. Yes, it's irrelevant.  I revert it.  please check it out. 
https://cr.openjdk.java.net/~xliu/8222670/webrev.02/

Please note that I added an assertion InstanceKlass::add_osr_nmethod(nmethod* n) in this webrev.
In my understanding, it is a potential memleak of codecache.  If there's no higher level of osr compilation, those dups will  stay in codecache forever. 

Further, it doesn’t make sense to recompile with the same level and same bci.  With this assertion, the following tests in tier1-test failed. 
test/hotspot/jtreg/compiler/intrinsics/unsafe/DirectByteBufferTest.java
test/hotspot/jtreg/compiler/intrinsics/unsafe/HeapByteBufferTest.java
test/jdk/java/util/stream/test/org/openjdk/tests/java/util/stream/ToArrayOpTest.java
test/jdk/tools/pack200/Pack200Test.java
test/jdk/java/util/Arrays/SortingNearlySortedPrimitive.java

All crashes happen as I described in JDK-8222670. Eg.  duplicated OSR compilations occur for level2.    

Program received signal SIGSEGV, Segmentation fault.
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc:  SuppressErrorAt=/instanceKlass.cpp:2972
#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (/src/src/hotspot/share/oops/instanceKlass.cpp:2972), pid=8347, tid=8361
#  assert(prev == __null || !prev->is_in_use()) failed: redundunt OSR recompilation detected. memory leak in CodeCache!
#
# JRE version: OpenJDK Runtime Environment (13.0) (slowdebug build 13-internal+0-adhoc..src)
# Java VM: OpenJDK 64-Bit Server VM (slowdebug 13-internal+0-adhoc..src, mixed mode, sharing, tiered, compressed oops, g1 gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0xb3dbb4]  InstanceKlass::add_osr_nmethod(nmethod*)+0xc4
#
# No core dump will be written. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
# /build/JTwork/scratch/hs_err_pid8347.log

Program received signal SIGSEGV, Segmentation fault.
Compiled method (c1)   19032  752 %     2       ByteBufferTest::stepUsingAccessors @ 382 (633 bytes)
 total in heap  [0x00007fffd8f9ff90,0x00007fffd8fac628] = 50840
 relocation     [0x00007fffd8fa0110,0x00007fffd8fa1388] = 4728
 main code      [0x00007fffd8fa13a0,0x00007fffd8fa7f80] = 27616
 stub code      [0x00007fffd8fa7f80,0x00007fffd8fa86c0] = 1856
 oops           [0x00007fffd8fa86c0,0x00007fffd8fa86c8] = 8
 metadata       [0x00007fffd8fa86c8,0x00007fffd8fa8800] = 312
 scopes data    [0x00007fffd8fa8800,0x00007fffd8fa9ff8] = 6136
 scopes pcs     [0x00007fffd8fa9ff8,0x00007fffd8fac408] = 9232
 dependencies   [0x00007fffd8fac408,0x00007fffd8fac418] = 16
 nul chk table  [0x00007fffd8fac418,0x00007fffd8fac628] = 528
Compiled method (c1)   19032  752 %     2       ByteBufferTest::stepUsingAccessors @ 382 (633 bytes)
 total in heap  [0x00007fffd8f9ff90,0x00007fffd8fac628] = 50840
 relocation     [0x00007fffd8fa0110,0x00007fffd8fa1388] = 4728
 main code      [0x00007fffd8fa13a0,0x00007fffd8fa7f80] = 27616
 stub code      [0x00007fffd8fa7f80,0x00007fffd8fa86c0] = 1856
 oops           [0x00007fffd8fa86c0,0x00007fffd8fa86c8] = 8
 metadata       [0x00007fffd8fa86c8,0x00007fffd8fa8800] = 312
 scopes data    [0x00007fffd8fa8800,0x00007fffd8fa9ff8] = 6136
 scopes pcs     [0x00007fffd8fa9ff8,0x00007fffd8fac408] = 9232
 dependencies   [0x00007fffd8fac408,0x00007fffd8fac418] = 16
 nul chk table  [0x00007fffd8fac418,0x00007fffd8fac628] = 528


Thanks, 
--lx

On 4/19/19, 9:31 AM, "Severin Gehwolf" <sgehwolf at redhat.com> wrote:

    On Thu, 2019-04-18 at 19:46 +0000, Liu, Xin wrote:
    > Hi, hotspot-compiler group,
    >  
    > Could you review this webrev for JDK-8222670?
    > https://cr.openjdk.java.net/~xliu/8222670/webrev.01/
    
    +++ new/test/hotspot/jtreg/compiler/tiered/TieredLevelsTest.java	2019-04-18 12:18:38.000000000 -0700
    @@ -89,7 +89,7 @@
                     && actual == COMP_LEVEL_LIMITED_PROFILE) {
                 // for simple method full_profile may be replaced by limited_profile
                 if (IS_VERBOSE) {
    -                System.out.printf("Level check: full profiling was replaced "
    +                System.out.println("Level check: full profiling was replaced "
                             + "by limited profiling. Expected: %d, actual:%d",
                             expected, actual);
    
    This seems an unintended change, is it?
    
    Thanks,
    Severin