RFR: 8265711: C1: Intrinsify Class.getModifier method [v2]

[Yi Yang]

On Tue, 27 Apr 2021 10:38:24 GMT, Yi Yang <yyang at openjdk.org> wrote:

>> src/hotspot/share/c1/c1_LIRGenerator.cpp line 1333:
>> 
>>> 1331:   // Checking if it's a java mirror of primitive type
>>> 1332:   __ move(new LIR_Address(receiver.result(), java_lang_Class::klass_offset(), T_ADDRESS), temp, info);
>>> 1333:   __ cmp(lir_cond_notEqual, temp, LIR_OprFact::metadataConst(0));
>> 
>> The previous version of your patch was missing the check for a primitive type. Why did testing not catch this?
>> 
>> Also, your PR title is misleading. You are not simply canonicalizing `Class.getModifier.` You are intrinsifying it.
>
> Because is_intrinsic_support is not aware of the fact that getModifiers is an intrinsic method. So canonicalizer is even not applied.
> 
>> Also, your PR title is misleading. You are not simply canonicalizing Class.getModifier. You are intrinsifying it.
> 
> Yes, exactly. Changed.

With the new IR test framework, these kinds of problem would never happen, we can do verification at IR level.

-------------

PR: https://git.openjdk.java.net/jdk/pull/3616