Reason for revert:
False alarm, bot hiccup
Original issue's description:
> Revert of Thread maybe-assigned through the bytecodes. (patchset #5 id:80001 of https://codereview.chromium.org/2655733003/ )
>
> Reason for revert:
> needed for properly reverting f3ae5ccf57
>
> Original issue's description:
> > Thread maybe-assigned through the bytecodes.
> >
> > This introduces LoadImmutableContextSlot and LoadImmutableCurrentContextSlot
> > bytecodes, which are emitted when reading from never-assigned context slot.
> >
> > There is a subtlety here: the slot are not immutable, the meaning is
> > actually undefined-or-hole-or-immutable.
> >
> > Review-Url: https://codereview.chromium.org/2655733003
> > Cr-Commit-Position: refs/heads/master@{#43000}
> > Committed: 17c2dd3886
>
> TBR=rmcilroy@chromium.org,bmeurer@chromium.org,neis@chromium.org,jarin@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Review-Url: https://codereview.chromium.org/2680923003
> Cr-Commit-Position: refs/heads/master@{#43011}
> Committed: ece4e54a31TBR=rmcilroy@chromium.org,bmeurer@chromium.org,neis@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review-Url: https://codereview.chromium.org/2679953003
Cr-Commit-Position: refs/heads/master@{#43012}
Reason for revert:
needed for properly reverting f3ae5ccf57
Original issue's description:
> Thread maybe-assigned through the bytecodes.
>
> This introduces LoadImmutableContextSlot and LoadImmutableCurrentContextSlot
> bytecodes, which are emitted when reading from never-assigned context slot.
>
> There is a subtlety here: the slot are not immutable, the meaning is
> actually undefined-or-hole-or-immutable.
>
> Review-Url: https://codereview.chromium.org/2655733003
> Cr-Commit-Position: refs/heads/master@{#43000}
> Committed: 17c2dd3886TBR=rmcilroy@chromium.org,bmeurer@chromium.org,neis@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review-Url: https://codereview.chromium.org/2680923003
Cr-Commit-Position: refs/heads/master@{#43011}
This introduces LoadImmutableContextSlot and LoadImmutableCurrentContextSlot
bytecodes, which are emitted when reading from never-assigned context slot.
There is a subtlety here: the slot are not immutable, the meaning is
actually undefined-or-hole-or-immutable.
Review-Url: https://codereview.chromium.org/2655733003
Cr-Commit-Position: refs/heads/master@{#43000}
We seem to get some small wins from avoiding the Ldr bytecodes, probably due
to reduced icache pressure since there are less bytecode handlers. Replace
the Ldr bytecodes with Star lookahead inlined into the Lda versions.
Also fixes IsAccumulatorLoadWithoutEffects to include LdaContextSlot and
LdaCurrentContextSlot
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2489513005
Cr-Commit-Position: refs/heads/master@{#40883}
The majority of context slot accesses are to the local context (current context
register and depth 0), so this adds bytecodes to optimise for that case.
This cuts down bytecode size by roughly 1% (measured on Octane and Top25).
Review-Url: https://codereview.chromium.org/2459513002
Cr-Commit-Position: refs/heads/master@{#40641}
Add a notion of "invocation count" to the baseline compilers, which
increment a special slot in the TypeFeedbackVector for each invocation
of a given function (the optimized code doesn't currently collect this
information).
Use this invocation count to relativize the call counts on the call
sites within the function, so that the inlining heuristic has a view
of relative importance of a call site rather than some absolute numbers
with unclear meaning for the current function. Also apply the call site
frequency as a factor to all frequencies in the inlinee by passing this
to the graph builders so that the importance of a call site in an
inlinee is relative to the topmost optimized function.
Note that all functions that neither have literals nor need type
feedback slots will share a single invocation count cell in the
canonical empty type feedback vector, so their invocation count is
meaningless, but that doesn't matter since we only use the invocation
count to relativize call counts within the function, which we only have
if we have at least one type feedback vector (the CallIC slot).
See the design document for additional details on this change:
https://docs.google.com/document/d/1VoYBhpDhJC4VlqMXCKvae-8IGuheBGxy32EOgC2LnT8
BUG=v8:5267,v8:5372
R=mvstanton@chromium.org,rmcilroy@chromium.org,mstarzinger@chromium.org
Review-Url: https://codereview.chromium.org/2337123003
Cr-Commit-Position: refs/heads/master@{#39410}
Moves the context chain search loop out of generated bytecode, and into
the (Lda|Ldr|Sda)ContextSlot handler, by passing the context depth in as
an additional operand. This should decrease the bytecode size and
increase performance for deep context chain searches, at the cost of
slightly increasing bytecode size for shallow context access.
Review-Url: https://codereview.chromium.org/2336643002
Cr-Commit-Position: refs/heads/master@{#39378}
For historical reasons, the interpreter's bytecode expectations tests
required a type for the constant pool. This had two disadvantages:
1. Strings and numbers were not visible in mixed pools, and
2. Mismatches of pool types (e.g. when rebaselining) would cause parser
errors
This removes the pool types, making everything 'mixed', but appending
the values to string and number valued constants. Specifying a pool type
in the *.golden header now prints a warning (for backwards compatibility).
BUG=v8:5350
Review-Url: https://codereview.chromium.org/2310103002
Cr-Commit-Position: refs/heads/master@{#39216}
Assign feedback slots in the type feedback vector for binary operations.
Update bytecode-generator to use these slots and add them as an operand
to binary operations.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/2209633002
Cr-Commit-Position: refs/heads/master@{#38408}
With this change the bytecode array builder only emits expression
positions for bytecodes that can throw. This allows more peephole
optimization opportunities and results in smaller code.
BUG=v8:4280,chromium:615979
LOG=N
Review-Url: https://codereview.chromium.org/2038323002
Cr-Commit-Position: refs/heads/master@{#36863}
This change introduces five fused bytecodes for common bytecode
sequences on popular websites. These are LdrNamedProperty,
LdrKeyedProperty, LdrGlobal, LdrContextSlot, and LdrUndefined. These
load values into a destination register operand instead of the
accumulator. They are emitted by the peephole optimizer.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/1985753002
Cr-Commit-Position: refs/heads/master@{#36507}
Prints source position information alongside bytecode.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/1963663002
Cr-Commit-Position: refs/heads/master@{#36171}
Bytecode expectations have been moved to external (.golden) files,
one per test. Each test in the suite builds a representation of the
the compiled bytecode using BytecodeExpectationsPrinter. The output is
then compared to the golden file. If the comparision fails, a textual
diff can be used to identify the discrepancies.
Only the test snippets are left in the cc file, which also allows to
make it more compact and meaningful. Leaving the snippets in the cc
file was a deliberate choice to allow keeping the "truth" about the
tests in the cc file, which will rarely change, as opposed to golden
files.
Golden files can be generated and kept up to date using
generate-bytecode-expectations, which also means that the test suite
can be batch updated whenever the bytecode or golden format changes.
The golden format has been slightly amended (no more comments about
`void*`, add size of the bytecode array) following the consideration
made while converting the tests.
There is also a fix: BytecodeExpectationsPrinter::top_level_ was left
uninitialized, leading to undefined behaviour.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1717293002
Cr-Commit-Position: refs/heads/master@{#34285}
