This patch provides the infrastructure to enable the exploitation of a GPU
by the compiler to accelerate certain suitable Java constructs.
When enabled, a suitable compiler can attempt to accelerate the following
Java constructs by launching the corresponding lambda expression on the
GPU:
IntStream.range(<range>).parallel().forEach(<lambda>)
IntStream.rangeClosed(<range>).parallel().forEach(<lambda>)
where:
<range> defines upper and lower bounds
<lambda> is a correctly defined lambda expression
As it stands, with the HotSpot compiler, this patch performs a "no op" in
the newly added in-built native library method.
This can be extended so that the HotSpot compiler attempts the
acceleration detailed above instead.
I would like to pair with a sponsor to contribute this patch ...
--------------------------------------------------------------------------------------------------------------
diff -r fd237da7a113 make/hotspot/symbols/symbols-unix
--- a/make/hotspot/symbols/symbols-unix Mon Jan 22 23:06:29 2018 -0800
+++ b/make/hotspot/symbols/symbols-unix Tue Jan 30 10:07:18 2018 +0000
@@ -1,5 +1,5 @@
#
-# Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights
reserved.
+# Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights
reserved.
# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
#
# This code is free software; you can redistribute it and/or modify it
@@ -187,3 +187,6 @@
JVM_AddReadsModule
JVM_DefineModule
JVM_SetBootLoaderUnnamedModule
+
+# GPU exploitation support
+Java_java_util_stream_IntPipeline_promoteGPUCompile
diff -r fd237da7a113 src/hotspot/share/include/jvm.h
--- a/src/hotspot/share/include/jvm.h Mon Jan 22 23:06:29 2018 -0800
+++ b/src/hotspot/share/include/jvm.h Tue Jan 30 10:07:18 2018 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights
reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights
reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -1189,6 +1189,12 @@
JNIEXPORT jstring JNICALL
JVM_GetTemporaryDirectory(JNIEnv *env);
+/*
+ * GPU exploitation support
+ */
+JNIEXPORT void JNICALL
+Java_java_util_stream_IntPipeline_promoteGPUCompile(JNIEnv *env, jobject
obj);
+
/* Generics reflection support.
*
* Returns information about the given class's EnclosingMethod
diff -r fd237da7a113 src/hotspot/share/prims/jvm.cpp
--- a/src/hotspot/share/prims/jvm.cpp Mon Jan 22 23:06:29 2018 -0800
+++ b/src/hotspot/share/prims/jvm.cpp Tue Jan 30 10:07:18 2018 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights
reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights
reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -3661,3 +3661,11 @@
JVM_ENTRY_NO_ENV(jint, JVM_FindSignal(const char *name))
return os::get_signal_number(name);
JVM_END
+
+
+// GPU exploitation support stub
/////////////////////////////////////////////////////////////////////
+
+JVM_ENTRY(void,
Java_java_util_stream_IntPipeline_promoteGPUCompile(JNIEnv *env, jobject
thisObj))
+ JVMWrapper("Java_java_util_stream_IntPipeline_promoteGPUCompile");
+ return;
+JVM_END
diff -r fd237da7a113
src/java.base/share/classes/java/util/stream/AbstractPipeline.java
--- a/src/java.base/share/classes/java/util/stream/AbstractPipeline.java
Mon Jan 22 23:06:29 2018 -0800
+++ b/src/java.base/share/classes/java/util/stream/AbstractPipeline.java
Tue Jan 30 10:07:18 2018 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights
reserved.
+ * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights
reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -373,6 +373,14 @@
return sourceStage.parallel;
}
+ /**
+ * Returns the sourceSpliterator
+ *
+ * @return the sourceSpliterator
+ */
+ final Spliterator<?> getSourceSpliterator() {
+ return sourceSpliterator;
+ }
/**
* Returns the composition of stream flags of the stream source and
all
diff -r fd237da7a113
src/java.base/share/classes/java/util/stream/IntPipeline.java
--- a/src/java.base/share/classes/java/util/stream/IntPipeline.java Mon
Jan 22 23:06:29 2018 -0800
+++ b/src/java.base/share/classes/java/util/stream/IntPipeline.java Tue
Jan 30 10:07:18 2018 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights
reserved.
+ * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights
reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -433,10 +433,33 @@
}
// Terminal ops from IntStream
+ private static boolean tryGPU = false;
+ protected static native void promoteGPUCompile();
@Override
public void forEach(IntConsumer action) {
- evaluate(ForEachOps.makeInt(action, false));
+ boolean instanceOfRangeIntSpliterator = getSourceSpliterator()
instanceof Streams.RangeIntSpliterator;
+ if (instanceOfRangeIntSpliterator) {
+ Streams.RangeIntSpliterator intRange =
(Streams.RangeIntSpliterator)getSourceSpliterator();
+ int last = intRange.upTo;
+ if (intRange.upTo != Integer.MAX_VALUE && intRange.last
== 1){
+ last = intRange.upTo + 1;
+ }
+ // tryGPU will be set at runtime using a suitable JVM
specific method option
+ if (tryGPU) {
+ for (int i = intRange.from; i < last; i++){
+ action.accept(i);
+ }
+ if (intRange.upTo == Integer.MAX_VALUE &&
intRange.last == 1){
+ action.accept(Integer.MAX_VALUE);
+ }
+ return;
+ }
+ }
+ evaluate(ForEachOps.makeInt(action, false));
+ if (instanceOfRangeIntSpliterator){
+ promoteGPUCompile();
+ }
}
@Override
diff -r fd237da7a113
src/java.base/share/classes/java/util/stream/Streams.java
--- a/src/java.base/share/classes/java/util/stream/Streams.java Mon Jan 22
23:06:29 2018 -0800
+++ b/src/java.base/share/classes/java/util/stream/Streams.java Tue Jan 30
10:07:18 2018 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights
reserved.
+ * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights
reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -55,12 +55,12 @@
// Can never be greater that upTo, this avoids overflow if upper
bound
// is Integer.MAX_VALUE
// All elements are traversed if from == upTo & last == 0
- private int from;
- private final int upTo;
+ int from;
+ final int upTo;
// 1 if the range is closed and the last element has not been
traversed
// Otherwise, 0 if the range is open, or is a closed range and
all
// elements have been traversed
- private int last;
+ int last;
RangeIntSpliterator(int from, int upTo, boolean closed) {
this(from, upTo, closed ? 1 : 0);
--------------------------------------------------------------------------------------------------------------
Regards,
Ben Walsh
Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number
741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU
