Adds support for populating reference maps to the fast
register allocator. In order to calculate whether a stack slot
is live at a given instruction, we use the dominator tree to
build a bitmap of blocks which are dominated by each block.
A variable's spill operand is classed as alive for any blocks that are
dominated by the block it was defined in, until the instruction index
of the spill operand's last use. As such, it may be classified as live
down a branch where the spill operand is never used, however it is safe
since the spill slot won't be re-allocated until after it's last-use
instruction index in any case.
BUG=v8:9684
Change-Id: I772374599ef916f57d82d468f66429e32c712ddf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2298008
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69108}
... that controls whether the TF graph zones should support compression.
Bug: v8:9923
Change-Id: Ifbe237b75e9c92e62eb32b69d6b3b1a818269b83
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2308347
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69036}
... by migrating old-style code
MyObject* obj = new (zone) MyObject(...)
to the new style
MyObject* obj = zone->New<MyObject>(...)
Bug: v8:10689
Change-Id: I55c686bbedfa1fd1955a5927df3f72b366312fd4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2288867
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68808}
Replace all usages of VectorSlotPair with FeedbackSource.
Bug: v8:7790
Change-Id: I0ac6e9cd8f5730154cc1842e267ca1ebfdebc874
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1763536
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63378}
This CL implements an assembly order optimization that moves blocks
that end a loop with an unconditional backedge to the beginning of
the loop, saving a branch.
R=jarin@chromium.org,mstarzinger@chromium.org
BUG=v8:8423
Change-Id: I8a5d25f5472d71227af0f623277ea8d0a8d69867
Reviewed-on: https://chromium-review.googlesource.com/c/1335944
Commit-Queue: Ben Titzer <titzer@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57572}
This CL splits the backend of TurboFan off into its own directory,
without changing namespaces. This makes ownership management a bit
more fine-grained with a logical separation.
R=mstarzinger@chromium.org,jarin@chromium.org,adamk@chromium.org
Change-Id: I2ac40d6ca2c4f04b8474b630aae0286ecf79ef42
Reviewed-on: https://chromium-review.googlesource.com/c/1308333
Commit-Queue: Ben Titzer <titzer@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57437}
The idea is to mark all the branches and loads participating in array
bounds checks, and let them contribute-to/use the poisoning register.
In the code, the marks for array indexing operations now contain
"Critical" in their name. By default (--untrusted-code-mitigations),
we only instrument the "critical" operations with poisoning.
With that in place, we also remove the array masking approach based
on arithmetic.
Since we do not propagate the poison through function calls,
we introduce a node for poisoning an index that is passed through
function call - the typical example is the bounds-checked index
that is passed to the CharCodeAt builtin.
Most of the code in this CL is threads through the three levels of
protection (safe, critical, unsafe) for loads, branches and flags.
Bug: chromium:798964
Change-Id: Ief68e2329528277b3ba9156115b2a6dcc540d52b
Reviewed-on: https://chromium-review.googlesource.com/995413
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52883}
This CL changes the poisoning in the interpreter to use the
infrastructure used in the JIT.
This does not change the original flag semantics:
--branch-load-poisoning enables JIT mitigations as before.
--untrusted-code-mitigation enables the interpreter mitigations
(now realized using the compiler back-end), but does not enable
the back-end based mitigations for the Javascript JIT. So in effect
--untrusted-code-mitigation makes the CSA pipeline for bytecode handlers
use the same mechanics (including changed register allocation) that
--branch-load-poisoning enables for the JIT.
Bug: chromium:798964
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: If7f6852ae44e32e6e0ad508e9237f24dec7e5b27
Reviewed-on: https://chromium-review.googlesource.com/928881
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52243}
Remove IsBlockTerminator and introduce InstructionScheduler::AddTerminator in
order to handle block terminator instructions.
Instead of the kBlockTerminator flags, we now rely on Instruction::IsTrap(),
Instruction::IsDeoptimizeCall() and explicitly denoting block terminators
when adding them with InstructionScheduler::AddTerminator().
IsBlockTerminator incorrectly included deopts when they were not at the end of
a block, which meant that an instruction with side effects could have been
reordered with respect to a deopt as the deopt was not identified correctly.
Since the snapshot does not contain deopts, this is not causing any problems
at the moment (the scheduler is only enabled on the snapshot).
Change-Id: I1c2dad748a9398a3355630d9a542f4ac89afaa42
Reviewed-on: https://chromium-review.googlesource.com/960501
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georgia Kouveli <georgia.kouveli@arm.com>
Cr-Commit-Position: refs/heads/master@{#52019}
