RFR (L): 8024545: make develop and notproduct flag values available in product builds

[Christian Thalinger]

On Sep 11, 2013, at 4:57 AM, Coleen Phillmore <coleen.phillimore at oracle.com> wrote:

> 
> Hi,
> 
> Have you done performance testing on this change?   When develop flags are not defined they are defined "const" false which enables the C++ compiler to do better optimizations.   I've seen code that counts on that.
> If you want the values to be materialized, why not change the develop flag definition to be extern const (or some such).

develop and notproduct flags are still constants; I didn't change that.  I've just put the const value in the flags table.

-- Chris

> 
> Coleen
> 
> On 9/10/2013 8:56 PM, Christian Thalinger wrote:
>> http://cr.openjdk.java.net/~twisti/8024545/webrev/
>> 
>> 8024545: make develop and notproduct flag values available in product builds
>> Reviewed-by:
>> 
>> Right now the internal flag table only contains flags which are defined in a product build. This does not include develop and notproduct flags. Sometimes it is useful to have access to these values for post-mortem core file analysis or to read these values for compiler settings for a Java-based compiler.
>> 
>> This change enables develop and notproduct flag values to be read by the serviceability agent. The binary size is increased by 42k for a 64-bit product build and by 32k for a 32-bit product build.
>> 
>> Before:
>> 
>> $ java -cp /java/re/jdk/8/latest/binaries/linux-x64/lib/sa-jdi.jar sun.jvm.hotspot.CLHSDB 9399
>> Attaching to process 9399, please wait...
>> hsdb> flags -nd
>> InitialHeapSize = 495006528 5
>> MaxHeapSize = 7920943104 5
>> UseCompressedKlassPointers = true 5
>> UseCompressedOops = true 5
>> UseParallelGC = true 5
>> hsdb> flags InlineMathNatives
>> Couldn't find flag: InlineMathNatives
>> 
>> After:
>> 
>> $ java -cp $JAVA_HOME/lib/sa-jdi.jar sun.jvm.hotspot.CLHSDB 3726
>> Attaching to process 3726, please wait...
>> hsdb> flags -nd
>> InitialHeapSize = 495006528 5
>> MaxHeapSize = 7920943104 5
>> UseCompressedKlassPointers = true 5
>> UseCompressedOops = true 5
>> UseParallelGC = true 5
>> hsdb> flags InlineMathNatives
>> InlineMathNatives = true 0
>> 
>> This patch has one behavioral difference; when printing flags with e.g. PrintFlagsFinal in a debug build it prints "develop" for develop flags:
>> 
>>     uintx AdaptiveSizePolicyGCTimeLimitThreshold    = 5               {develop}
>> 
>> The output for product builds is unchanged.
>