Hi Rémi,
are you confusing package names with module names?
From the linked specification:
"Package names referenced from the Module attribute are stored in
CONSTANT_Package_info entries in the constant pool. Such entries wrap
CONSTANT_Utf8_info entries which represent package names encoded in
internal form."
This still appears necessary since loading the module establishes the
symbol entries representing the referenced packages.
Thanks!
/Claes
On 2017-01-03 00:06, Remi Forax wrote:
Hi Claes,
the whole replace dance should not be needed anymore with the latest revision
of the spec,
module names are not stored in internal form anymore.
see http://cr.openjdk.java.net/~mr/jigsaw/spec/lang-vm.html#jigsaw-2.1
Rémi
----- Mail original -----
De: "Claes Redestad" <claes.redes...@oracle.com>
À: "jigsaw-dev" <jigsaw-dev@openjdk.java.net>,
hotspot-runtime-...@openjdk.java.net
Envoyé: Lundi 2 Janvier 2017 19:27:43
Objet: RFR: 8171855: Move package name transformations during module
bootstrap into VM
Hi,
during jigsaw bootstrap, package names - represented in external form,
"java.lang" - are transformed into VM internal form, "java/lang",
before calling into the VM.
This, however, can effectively be moved into the VM, which removes the
need to generate a lot of short-lived strings during bootstrap and heat
up various String.replace-related methods. This has a noticeable impact
on startup metrics.
Webrev: http://cr.openjdk.java.net/~redestad/8171855/
Bug: https://bugs.openjdk.java.net/browse/JDK-8171855
JPRT -testset hotspot pass, and I've prepared to push this into jdk9/hs
if there are no objections.
Char-based replace on a UTF-8 source should be correct as long as the
from and to chars are ASCII (0x00 through 0x7F). A more general method
would be needed to safely deal with char values above 0x7F, so adding
some asserts to that effect should be considered.
Thanks!
/Claes
