RFR: 8216361: Deprecate -XX:CompilationPolicyChoice

[Claes Redestad]

Hi,

while CompilationPolicyChoice can be used to enable the legacy
StackWalkerCompPolicy when running -XX:-TieredCompilation, this policy
has been shown to be a pessimization on most benchmarks since 1.5.

Let's deprecate it in 13 and plan to obsolete (remove) it along with the
StackWalkerCompPolicy in 14.

Bug: https://bugs.openjdk.java.net/browse/JDK-8216361

Testing: tier1

Thanks!

/Claes

diff -r ee45b48c9e4a src/hotspot/share/runtime/arguments.cpp
--- a/src/hotspot/share/runtime/arguments.cpp	Tue Feb 12 19:22:19 2019 +0100
+++ b/src/hotspot/share/runtime/arguments.cpp	Wed Feb 13 11:13:22 2019 +0100
@@ -528,6 +528,7 @@
    { "MinRAMFraction",               JDK_Version::jdk(10), 
JDK_Version::undefined(), JDK_Version::undefined() },
    { "InitialRAMFraction",           JDK_Version::jdk(10), 
JDK_Version::undefined(), JDK_Version::undefined() },
    { "UseMembar",                    JDK_Version::jdk(10), 
JDK_Version::jdk(12), JDK_Version::undefined() },
+  { "CompilationPolicyChoice",      JDK_Version::jdk(13), 
JDK_Version::jdk(14), JDK_Version::undefined() },

    // --- Deprecated alias flags (see also aliased_jvm_flags) - sorted 
by obsolete_in then expired_in:
    { "DefaultMaxRAMFraction",        JDK_Version::jdk(8), 
JDK_Version::undefined(), JDK_Version::undefined() },