RFR: 8312235: [JVMCI] ConstantPool should not force eager resolution [v4]

Doug Simon dnsimon at openjdk.org
Wed Jul 26 16:11:11 UTC 2023


> The existing `jdk.vm.ci.meta.ConstantPool.lookupConstant(int cpi)` method forces eager resolving of constants. For `DynamicConstant`, `MethodHandle` and `MethodType`, this can mean invoking bootstrap methods, something that should not be done during JIT compilation. To avoid this, this PR adds the following to `jdk.vm.ci.meta.ConstantPool`:
> 
> 
> /**
>  * Looks up a constant at the specified index.
>  *
>  * If {@code resolve == false} and the denoted constant is of type
>  * {@code JVM_CONSTANT_Dynamic}, {@code JVM_CONSTANT_MethodHandle} or
>  * {@code JVM_CONSTANT_MethodType} and it's not yet resolved then
>  * {@code null} is returned.
>  *
>  * @param cpi the constant pool index
>  * @return the {@code Constant} or {@code JavaType} instance representing the constant pool
>  *         entry
>  */
> Object lookupConstant(int cpi, boolean resolve);
> 
> 
> Likewise, `jdk.vm.ci.meta.ConstantPool.lookupBootstrapMethodInvocation` has been fixed to no longer invoke the associated bootstrap method.
> 
> ---------
> ### Progress
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> 
> 
> 
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Doug Simon has updated the pull request incrementally with one additional commit since the last revision:

  renamed index to cp_index

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/14927/files
  - new: https://git.openjdk.org/jdk/pull/14927/files/5ada646c..1ca9ab68

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14927&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14927&range=02-03

  Stats: 5 lines in 1 file changed: 0 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/14927.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14927/head:pull/14927

PR: https://git.openjdk.org/jdk/pull/14927


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