8316533: C2 compilation fails with assert(verify(phase)) failed: missing Value() optimization

Reviewed-by: rcastanedalo, thartmann, roland
This commit is contained in:
Emanuel Peter 2023-11-06 10:41:09 +00:00
parent 377138c7b5
commit b5c863b772
2 changed files with 76 additions and 0 deletions
src/hotspot/share/opto
test/hotspot/jtreg/compiler/types

@ -43,6 +43,18 @@ const Type* SubTypeCheckNode::sub(const Type* sub_t, const Type* super_t) const
if (!superklass->is_interface() && superklass->is_abstract() &&
!superklass->as_instance_klass()->has_subklass()) {
Compile::current()->dependencies()->assert_leaf_type(superklass);
if (subk->is_same_java_type_as(superk) && !sub_t->maybe_null()) {
// The super_t has no subclasses, and sub_t has the same type and is not null,
// hence the check should always evaluate to EQ. However, this is an impossible
// situation since super_t is also abstract, and hence sub_t cannot have the
// same type and be non-null.
// Still, if the non-static method of an abstract class without subclasses is
// force-compiled, the Param0 has the self/this pointer with NotNull. This
// method would now never be called, because of the leaf-type dependency. Hence,
// just for consistency with verification, we return EQ.
return TypeInt::CC_EQ;
}
// subk is either a supertype of superk, or null. In either case, superk is a subtype.
return TypeInt::CC_GT;
}
}

@ -0,0 +1,64 @@
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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*
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*
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/**
* @test
* @bug 8316533
* @summary Oop of abstract class A with no subclass is subtype checked after null-check
* @run driver compiler.types.TestSubTypeOfAbstractClass
*/
/**
* @test
* @bug 8316533
* @summary Oop of abstract class A is subtype checked after null-check
* @requires vm.compiler2.enabled
* @run main/othervm -XX:CompileCommand=compileonly,*A::test
* -Xcomp -XX:+IgnoreUnrecognizedVMOptions -XX:+StressReflectiveCode
* compiler.types.TestSubTypeOfAbstractClass
*/
package compiler.types;
public class TestSubTypeOfAbstractClass {
abstract class A {
public static A get_null() {
return null;
}
public static boolean test() {
// NullCheck -> CastPP with type A:NotNull
// But A is abstract with no subclass, hence this type is impossible
return get_null() instanceof A;
}
}
public static void main(String[] args) {
for (int i = 0; i < 10_000; i++ ) {
A.test();
}
}
}