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@rednaxelafx
Created May 29, 2012 19:28
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First cut: C1 Class.isInstance intrinsic
diff -r 4d8787136e08 src/share/vm/c1/c1_Canonicalizer.cpp
--- a/src/share/vm/c1/c1_Canonicalizer.cpp Fri May 25 11:39:13 2012 -0700
+++ b/src/share/vm/c1/c1_Canonicalizer.cpp Wed May 30 03:21:56 2012 +0800
@@ -451,6 +451,28 @@
}
break;
}
+ case vmIntrinsics::_isInstance : {
+ assert(x->number_of_arguments() == 2, "wrong type");
+
+ InstanceConstant* c = x->argument_at(0)->type()->as_InstanceConstant();
+ if (c != NULL && !c->value()->is_null_object()) {
+ // ciInstance::java_mirror_type() returns non-NULL only for Java mirrors
+ ciType* t = c->value()->as_instance()->java_mirror_type();
+ if (t->is_klass()) {
+ // substitute cls.isInstance(obj) of a constant Class into
+ // an InstantOf instruction
+ InstanceOf* i = new InstanceOf(t->as_klass(), x->argument_at(1), x->state());
+ set_canonical(i);
+ // and try to canonicalize even further
+ do_InstanceOf(i);
+ } else {
+ assert(t->is_primitive_type(), "should be a primitive type");
+ // cls.isInstance(obj) always returns false for primitive classes
+ set_constant(0);
+ }
+ }
+ break;
+ }
}
}
diff -r 4d8787136e08 src/share/vm/c1/c1_GraphBuilder.cpp
--- a/src/share/vm/c1/c1_GraphBuilder.cpp Fri May 25 11:39:13 2012 -0700
+++ b/src/share/vm/c1/c1_GraphBuilder.cpp Wed May 30 03:21:56 2012 +0800
@@ -3170,6 +3170,7 @@
break;
case vmIntrinsics::_getClass :
+ case vmIntrinsics::_isInstance :
if (!InlineClassNatives) return false;
preserves_state = true;
break;
diff -r 4d8787136e08 src/share/vm/c1/c1_LIRGenerator.cpp
--- a/src/share/vm/c1/c1_LIRGenerator.cpp Fri May 25 11:39:13 2012 -0700
+++ b/src/share/vm/c1/c1_LIRGenerator.cpp Wed May 30 03:21:56 2012 +0800
@@ -1242,6 +1242,36 @@
NULL /* info */);
}
+// Example: clazz.isInstance(object)
+void LIRGenerator::do_isInstance(Intrinsic* x) {
+ assert(x->number_of_arguments() == 2, "wrong type");
+
+ // TODO could try to substitute this node with an equivalent InstanceOf
+ // if clazz is known to be a constant Class. This will pick up newly found
+ // constants after HIR construction. I'll leave this to a future change.
+
+ // as a first cut, make a simple leaf call to runtime to stay platform independent.
+ // could follow the aastore example in a future change.
+
+ LIRItem clazz(x->argument_at(0), this);
+ LIRItem object(x->argument_at(1), this);
+ clazz.load_item();
+ object.load_item();
+ LIR_Opr result = rlock_result(x);
+
+ // need to perform null check on clazz
+ if (x->needs_null_check()) {
+ CodeEmitInfo* info = state_for(x);
+ __ null_check(clazz.result(), info);
+ }
+
+ LIR_Opr call_result = call_runtime(clazz.value(), object.value(),
+ CAST_FROM_FN_PTR(address, Runtime1::is_instance_of),
+ x->type(),
+ NULL); // NULL CodeEmitInfo results in a leaf call
+ __ move(call_result, result);
+}
+
// Example: object.getClass ()
void LIRGenerator::do_getClass(Intrinsic* x) {
assert(x->number_of_arguments() == 1, "wrong type");
@@ -2951,6 +2981,7 @@
break;
case vmIntrinsics::_Object_init: do_RegisterFinalizer(x); break;
+ case vmIntrinsics::_isInstance: do_isInstance(x); break;
case vmIntrinsics::_getClass: do_getClass(x); break;
case vmIntrinsics::_currentThread: do_currentThread(x); break;
diff -r 4d8787136e08 src/share/vm/c1/c1_LIRGenerator.hpp
--- a/src/share/vm/c1/c1_LIRGenerator.hpp Fri May 25 11:39:13 2012 -0700
+++ b/src/share/vm/c1/c1_LIRGenerator.hpp Wed May 30 03:21:56 2012 +0800
@@ -238,6 +238,7 @@
LIR_Opr getThreadPointer();
void do_RegisterFinalizer(Intrinsic* x);
+ void do_isInstance(Intrinsic* x);
void do_getClass(Intrinsic* x);
void do_currentThread(Intrinsic* x);
void do_MathIntrinsic(Intrinsic* x);
diff -r 4d8787136e08 src/share/vm/c1/c1_Runtime1.cpp
--- a/src/share/vm/c1/c1_Runtime1.cpp Fri May 25 11:39:13 2012 -0700
+++ b/src/share/vm/c1/c1_Runtime1.cpp Wed May 30 03:21:56 2012 +0800
@@ -294,6 +294,7 @@
FUNCTION_CASE(entry, SharedRuntime::lrem);
FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
+ FUNCTION_CASE(entry, is_instance_of);
FUNCTION_CASE(entry, trace_block_entry);
#ifdef TRACE_HAVE_INTRINSICS
FUNCTION_CASE(entry, TRACE_TIME_METHOD);
@@ -1270,6 +1271,19 @@
JRT_END
+JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
+ // had to return int instead of bool, otherwise there may be a mismatch
+ // between the C calling convention and the Java one.
+ // e.g., on x86, GCC may clear only %al when returning a bool false, but
+ // JVM takes the whole %eax as the return value, which may misinterpret
+ // the return value as a boolean true.
+
+ assert(mirror != NULL, "should null-check on mirror before calling");
+ klassOop k = java_lang_Class::as_klassOop(mirror);
+ return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
+JRT_END
+
+
#ifndef PRODUCT
void Runtime1::print_statistics() {
tty->print_cr("C1 Runtime statistics:");
diff -r 4d8787136e08 src/share/vm/c1/c1_Runtime1.hpp
--- a/src/share/vm/c1/c1_Runtime1.hpp Fri May 25 11:39:13 2012 -0700
+++ b/src/share/vm/c1/c1_Runtime1.hpp Wed May 30 03:21:56 2012 +0800
@@ -186,6 +186,7 @@
static int arraycopy(oopDesc* src, int src_pos, oopDesc* dst, int dst_pos, int length);
static void primitive_arraycopy(HeapWord* src, HeapWord* dst, int length);
static void oop_arraycopy(HeapWord* src, HeapWord* dst, int length);
+ static int is_instance_of(oopDesc* mirror, oopDesc* obj);
static void print_statistics() PRODUCT_RETURN;
};
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