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  1. JDK
  2. JDK-8277417

C1 LIR instruction for load-klass

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    • b26
    • x86, arm, ppc, x86_64, aarch64, s390x
    • generic

    Backports

      Description

        In C1, the load of a Klass* out of an object is currently identified by a load of type T_ADDRESS with offset oopDest::klass_offset_in_bytes(). When encountering such load, this may be decoded when +CompressedClassPointers. This is problematic and ugly: if we ever emit a T_ADDRESS load with offset 8 or 4 (== klass_offset_in_bytes) that is not a Klass*, we would attempt to decode the result. We have been lucky so far.

        Also, in Lilliput, we want to do something entirely different there, and need to be able to emit more complex code, possibly including runtime call.

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            backported by

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8311637 C1 LIR instruction for load-klass

            • P3 - Major loss of function.
            • Resolved
            relates to

            Bug - A problem which impairs or prevents the functions of the product. JDK-8278141 LIR_OpLoadKlass::_info shadows the field of the same name from LIR_Op

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Enhancement - null JDK-8026837 C1: metadata klass pointers should be of type T_METADATA

            • P3 - Major loss of function.
            • Open

            Enhancement - null JDK-8277860 PPC: Remove duplicate info != NULL check

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved
            links to

            Commit Commit openjdk/jdk17u-dev/966fc82d

            Commit Commit openjdk/jdk17u-dev/d7a59f37

            Commit Commit openjdk/jdk/99e4bda3

            Review Review openjdk/jdk17u-dev/1427

            Review Review openjdk/jdk17u-dev/1528

            Review Review openjdk/jdk/6464

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                rkennke Roman Kennke
                rkennke Roman Kennke
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                Dates

                  Created:
                  Updated:
                  Resolved: