RFR: NewInstanceStub reads InstanceKlass::_init_state as int but is u1

[Doug Simon]

Looks good.

On Jul 24, 2013, at 3:23 AM, Christian Thalinger <christian.thalinger at oracle.com> wrote:

> Here are a couple more fixes to this code.  The threadAllocatedBytesOffset change is not really necessary but since it's defined as a long:
> 
>  jlong _allocated_bytes;                       // Cumulative number of bytes allocated on
> 
> we should read it as a long.
> 
> -- Chris
> 
> diff -r 6057d0168f47 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/stubs/NewInstanceStub.java
> --- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/stubs/NewInstanceStub.java	Tue Jul 23 12:27:06 2013 -0700
> +++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/stubs/NewInstanceStub.java	Tue Jul 23 18:20:38 2013 -0700
> @@ -89,7 +89,7 @@ public class NewInstanceStub extends Sni
>     private static Object newInstance(Word hub, @ConstantParameter Word intArrayHub) {
>         int sizeInBytes = hub.readInt(klassInstanceSizeOffset(), LocationIdentity.FINAL_LOCATION);
>         if (!forceSlowPath() && inlineContiguousAllocationSupported()) {
> -            if (hub.readInt(klassStateOffset(), CLASS_STATE_LOCATION) == klassStateFullyInitialized()) {
> +            if (hub.readByte(klassStateOffset(), CLASS_STATE_LOCATION) == klassStateFullyInitialized()) {
>                 Word memory = refillAllocate(intArrayHub, sizeInBytes, logging());
>                 if (memory.notEqual(0)) {
>                     Word prototypeMarkWord = hub.readWord(prototypeMarkWordOffset(), PROTOTYPE_MARK_WORD_LOCATION);
> @@ -137,21 +137,21 @@ public class NewInstanceStub extends Sni
>         Word end = readTlabEnd(thread);
> 
>         // calculate amount of free space
> -        Word tlabFreeSpaceInBytes = end.subtract(top);
> +        long tlabFreeSpaceInBytes = end.subtract(top).rawValue();
> 
>         if (log) {
>             printf("refillTLAB: thread=%p\n", thread.rawValue());
>             printf("refillTLAB: top=%p\n", top.rawValue());
>             printf("refillTLAB: end=%p\n", end.rawValue());
> -            printf("refillTLAB: tlabFreeSpaceInBytes=%d\n", tlabFreeSpaceInBytes.rawValue());
> +            printf("refillTLAB: tlabFreeSpaceInBytes=%ld\n", tlabFreeSpaceInBytes);
>         }
> 
> -        Word tlabFreeSpaceInWords = tlabFreeSpaceInBytes.unsignedShiftRight(log2WordSize());
> +        long tlabFreeSpaceInWords = tlabFreeSpaceInBytes >>> log2WordSize();
> 
>         // Retain TLAB and allocate object in shared space if
>         // the amount free in the TLAB is too large to discard.
>         Word refillWasteLimit = thread.readWord(tlabRefillWasteLimitOffset(), TLAB_REFILL_WASTE_LIMIT_LOCATION);
> -        if (tlabFreeSpaceInWords.belowOrEqual(refillWasteLimit)) {
> +        if (tlabFreeSpaceInWords <= refillWasteLimit.rawValue()) {
>             if (tlabStats()) {
>                 // increment number of refills
>                 thread.writeInt(tlabNumberOfRefillsOffset(), thread.readInt(tlabNumberOfRefillsOffset(), TLAB_NOF_REFILLS_LOCATION) + 1, TLAB_NOF_REFILLS_LOCATION);
> @@ -159,11 +159,11 @@ public class NewInstanceStub extends Sni
>                     printf("thread: %p -- number_of_refills %d\n", thread.rawValue(), thread.readInt(tlabNumberOfRefillsOffset(), TLAB_NOF_REFILLS_LOCATION));
>                 }
>                 // accumulate wastage
> -                Word wastage = thread.readWord(tlabFastRefillWasteOffset(), TLAB_FAST_REFILL_WASTE_LOCATION).add(tlabFreeSpaceInWords);
> +                int wastage = thread.readInt(tlabFastRefillWasteOffset(), TLAB_FAST_REFILL_WASTE_LOCATION) + (int) tlabFreeSpaceInWords;
>                 if (log) {
> -                    printf("thread: %p -- accumulated wastage %d\n", thread.rawValue(), wastage.rawValue());
> +                    printf("thread: %p -- accumulated wastage %d\n", thread.rawValue(), wastage);
>                 }
> -                thread.writeWord(tlabFastRefillWasteOffset(), wastage, TLAB_FAST_REFILL_WASTE_LOCATION);
> +                thread.writeInt(tlabFastRefillWasteOffset(), wastage, TLAB_FAST_REFILL_WASTE_LOCATION);
>             }
> 
>             // if TLAB is currently allocated (top or end != null) then
> @@ -172,13 +172,13 @@ public class NewInstanceStub extends Sni
>                 int headerSize = arrayBaseOffset(Kind.Int);
>                 // just like the HotSpot assembler stubs, assumes that tlabFreeSpaceInInts fits in
>                 // an int
> -                int tlabFreeSpaceInInts = (int) tlabFreeSpaceInBytes.rawValue() >>> 2;
> +                int tlabFreeSpaceInInts = (int) tlabFreeSpaceInBytes >>> 2;
>                 int length = ((alignmentReserveInBytes - headerSize) >>> 2) + tlabFreeSpaceInInts;
>                 NewObjectSnippets.formatArray(intArrayHub, -1, length, headerSize, top, intArrayMarkWord, false);
> 
> -                Word allocated = thread.readWord(threadAllocatedBytesOffset(), TLAB_THREAD_ALLOCATED_BYTES_LOCATION);
> -                allocated = allocated.add(top.subtract(readTlabStart(thread)));
> -                thread.writeWord(threadAllocatedBytesOffset(), allocated, TLAB_THREAD_ALLOCATED_BYTES_LOCATION);
> +                long allocated = thread.readLong(threadAllocatedBytesOffset(), TLAB_THREAD_ALLOCATED_BYTES_LOCATION);
> +                allocated = allocated + top.subtract(readTlabStart(thread)).rawValue();
> +                thread.writeLong(threadAllocatedBytesOffset(), allocated, TLAB_THREAD_ALLOCATED_BYTES_LOCATION);
>             }
> 
>             // refill the TLAB with an eden allocation
> 
> On Jul 23, 2013, at 2:09 PM, Christian Thalinger <christian.thalinger at oracle.com> wrote:
> 
>> _init_state is defined as u1 in InstanceKlass:
>> 
>> u1              _init_state;                    // state of class
>> 
>> but is read as int in newInstance:
>> 
>> diff -r 6057d0168f47 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/stubs/NewInstanceStub.java
>> --- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/stubs/NewInstanceStub.java	Tue Jul 23 12:27:06 2013 -0700
>> +++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/stubs/NewInstanceStub.java	Tue Jul 23 14:06:49 2013 -0700
>> @@ -89,7 +89,7 @@ public class NewInstanceStub extends Sni
>>    private static Object newInstance(Word hub, @ConstantParameter Word intArrayHub) {
>>        int sizeInBytes = hub.readInt(klassInstanceSizeOffset(), LocationIdentity.FINAL_LOCATION);
>>        if (!forceSlowPath() && inlineContiguousAllocationSupported()) {
>> -            if (hub.readInt(klassStateOffset(), CLASS_STATE_LOCATION) == klassStateFullyInitialized()) {
>> +            if (hub.readByte(klassStateOffset(), CLASS_STATE_LOCATION) == klassStateFullyInitialized()) {
>>                Word memory = refillAllocate(intArrayHub, sizeInBytes, logging());
>>                if (memory.notEqual(0)) {
>>                    Word prototypeMarkWord = hub.readWord(prototypeMarkWordOffset(), PROTOTYPE_MARK_WORD_LOCATION);
>> 
>> -- Chris
>