deps: cherry-pick 7c982e7 from V8 upstream
Original commit message:
PPC/s390: [Turbofan]: Use new MachineTypes in access-builder.
Port 56429fc14671a10749190a4dfeacd38b7270f6f5
Original Commit Message:
Introduced MachineType::TaggedSigned() and TaggedPointer().
The idea is to quit using the representational dimension of Type, and
instead encode this information in the MachineRepresentation (itself
lightly wrapped in MachineType, along with MachineSemantic).
There are three parts to the whole change:
1) Places that set the machine representation - constant nodes, loads nad
stores, global object and native context specialization.
2) Places that propagate type/representation - this is representation
inference (aka simplified lowering). At the end of this process we
expect to have a MachineRepresentation for every node. An interesting
part of this is phi merging.
3) Places that examine representation - WriteBarrier elimination does this.
Currently it's looking at the Type representation dimension, but as
a part of this change (or in a soon-to-follow change) it can simply
examine the MachineRepresentation.
R=mvstanton@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N
Review-Url: https://codereview.chromium.org/2662223003
Cr-Commit-Position: refs/heads/master@{#42817}
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
tests and/or benchmarks are included -
commit message follows commit guidelines
Affected core subsystem(s)
V8
Description of change
This port is in V8 5.6/5.7 but couldn't make it to V8 5.5. When node master moves to 5.6, it should have this commit, so only affects node version with V8 5.5
/cc @nodejs/v8