This reverts commit cf93071c91.
Reason for revert: Speculative revert because of Mac4 GC stress failure: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Mac64%20GC%20Stress/16697/overview
Original change's description:
> [interpreter] Short Star bytecode
>
> Design doc:
> https://docs.google.com/document/d/1g_NExMT78II_KnIYNa9MvyPYIj23qAiFUEsyemY5KRk/edit
>
> This change adds 16 new interpreter opcodes, kStar0 through kStar15, so
> that we can use a single byte to represent the common operation of
> storing to a low-numbered register. This generally reduces the quantity
> of bytecode generated on web sites by 8-9%.
>
> In order to not degrade speed, a couple of other changes are required:
>
> The existing lookahead logic to check for Star after certain other
> bytecode handlers is updated to check for these new short Star codes
> instead. Furthermore, that lookahead logic is updated to contain its own
> copy of the dispatch jump rather than merging control flow with the
> lookahead-failed case, to improve branch prediction.
>
> A bunch of constants use bytecode size in bytes as a proxy for the size
> or complexity of a function, and are adjusted downward proportionally to
> the decrease in generated bytecode size.
>
> Other small drive-by fix: update generate-bytecode-expectations to emit
> \n instead of \r\n on Windows.
>
> Change-Id: I6307c2b0f5794a3a1088bb0fb94f6e1615441ed5
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2641180
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Cr-Commit-Position: refs/heads/master@{#72773}
TBR=rmcilroy@chromium.org,mythria@chromium.org,seth.brenith@microsoft.com
Change-Id: I0162b9400861b90bacef27cca9aebc8ab9d74c10
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2697350
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72777}
Design doc:
https://docs.google.com/document/d/1g_NExMT78II_KnIYNa9MvyPYIj23qAiFUEsyemY5KRk/edit
This change adds 16 new interpreter opcodes, kStar0 through kStar15, so
that we can use a single byte to represent the common operation of
storing to a low-numbered register. This generally reduces the quantity
of bytecode generated on web sites by 8-9%.
In order to not degrade speed, a couple of other changes are required:
The existing lookahead logic to check for Star after certain other
bytecode handlers is updated to check for these new short Star codes
instead. Furthermore, that lookahead logic is updated to contain its own
copy of the dispatch jump rather than merging control flow with the
lookahead-failed case, to improve branch prediction.
A bunch of constants use bytecode size in bytes as a proxy for the size
or complexity of a function, and are adjusted downward proportionally to
the decrease in generated bytecode size.
Other small drive-by fix: update generate-bytecode-expectations to emit
\n instead of \r\n on Windows.
Change-Id: I6307c2b0f5794a3a1088bb0fb94f6e1615441ed5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2641180
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#72773}
FunctionEntry StackChecks is one of the two cases where we generate a
StackCheck bytecode. In these cases, we do stack check against the js
limit (not to be confused with the real js limit). Their purpose is to
be able to interrupt the running code.
We can omit the FunctionEntry StackCheck by embedding its code into
the InterpreterEntryTrampoline builtin. We save one bytecode per
interpreted function.
This change has rippling effects for optimized code, as well as the
deoptimizer.
Bug: v8:10149, v8:9977, v8:9960
Change-Id: I6156de48b3bc0b519dd21190a8e6214fbe96c78d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1914218
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66206}
Instead of having feedback vector as a subtype of FixedArray with
reserved slots, make it a first-class variable-sized object with a
fixed-size header. This allows us to compress counters to ints in the
header, rather than forcing them to be Smis.
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: Icc5f088ffbc2e2651b845bc71ea42060639e3e48
Reviewed-on: https://chromium-review.googlesource.com/585129
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46935}
Reland of https://chromium-review.googlesource.com/c/544888/.
Instead of counting profiler ticks on the shared function info (which is
shared between native contexts), count them on the feedback vector
(which is not). This allows us to continue pushing optimization
decisions off the SFI, onto the feedback vector.
Note that a side-effect of this is that ICs don't have to walk the stack
to reset profiler ticks, as they can access the feedback vector directly
from their feedback nexus.
Change-Id: I7aa6baed03f726843d1b62629c72b74f05114b48
Reviewed-on: https://chromium-review.googlesource.com/579051
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46868}
This reverts commit a2fcdc7cc8.
Reason for revert: Large regressions in RCS (https://chromeperf.appspot.com/group_report?bug_id=740126)
Original change's description:
> [runtime] Move profiler ticks from SFI to feedback vector
>
> Instead of counting profiler ticks on the shared function info (which is
> shared between native contexts), count them on the feedback vector
> (which is not). This allows us to continue pushing optimization
> decisions off the SFI, onto the feedback vector.
>
> Note that a side-effect of this is that ICs don't have to walk the stack
> to reset profiler ticks, as they can access the feedback vector directly
> from their feedback nexus.
>
> Change-Id: I232ae9e759fca75cd89d393148a4ff42caa2646f
> Reviewed-on: https://chromium-review.googlesource.com/544888
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#46411}
TBR=rmcilroy@chromium.org,leszeks@chromium.org,ishell@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
Change-Id: Id587e4172e300c420f93c49744a2a0e66696edf8
Reviewed-on: https://chromium-review.googlesource.com/574227
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46702}
Goal of this CL: explicit return from non-async function has position after
return expression as return position (will unblock [1]).
BytecodeArrayBuilder has SetStatementPosition and SetExpressionPosition methods.
If one of these methods is called then next generated bytecode will get passed
position. It's general treatment for most cases.
Unfortunately it doesn't work for Returns:
- debugger requires source positions exactly on kReturn bytecode in stepping
implementation,
- BytecodeGenerator::BuildReturn and BytecodeGenerator::BuildAsyncReturn
generates more then one bytecode and general solution will put return position
on first generated bytecode,
- it's not easy to split BuildReturn function into two parts to allow something
like following in BytecodeGenerator::VisitReturnStatement since generated
bytecodes are actually controlled by execution_control().
..->BuildReturnPrologue();
..->SetReturnPosition(stmt);
..->Return();
In this CL we pass ReturnStatement through ExecutionControl and use it for
position when we emit return bytecode right here.
So this CL only will improve return position for returns inside of non-async
functions, I'll address async functions later.
[1] https://chromium-review.googlesource.com/c/543161/
Change-Id: Iede512c120b00c209990bf50c20e7d23dc0d65db
Reviewed-on: https://chromium-review.googlesource.com/560738
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46687}
Instead of counting profiler ticks on the shared function info (which is
shared between native contexts), count them on the feedback vector
(which is not). This allows us to continue pushing optimization
decisions off the SFI, onto the feedback vector.
Note that a side-effect of this is that ICs don't have to walk the stack
to reset profiler ticks, as they can access the feedback vector directly
from their feedback nexus.
Change-Id: I232ae9e759fca75cd89d393148a4ff42caa2646f
Reviewed-on: https://chromium-review.googlesource.com/544888
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46411}
Since the feedback vector is itself a native context structure, why
not store optimized code for a function in there rather than in
a map from native context to code? This allows us to get rid of
the optimized code map in the SharedFunctionInfo, saving a pointer,
and making lookup of any optimized code quicker.
Original patch by Michael Stanton <mvstanton@chromium.org>
BUG=v8:6246,chromium:718891
TBR=yangguo@chromium.org,ulan@chromium.org
Change-Id: I3bb9ec0cfff32e667cca0e1403f964f33a6958a6
Reviewed-on: https://chromium-review.googlesource.com/500134
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45234}
This reverts commit 662aa425ba.
Reason for revert: Crashing on Canary
BUG=chromium:718891
Original change's description:
> Reland: [TypeFeedbackVector] Store optimized code in the vector
>
> Since the feedback vector is itself a native context structure, why
> not store optimized code for a function in there rather than in
> a map from native context to code? This allows us to get rid of
> the optimized code map in the SharedFunctionInfo, saving a pointer,
> and making lookup of any optimized code quicker.
>
> Original patch by Michael Stanton <mvstanton@chromium.org>
>
> BUG=v8:6246
> TBR=yangguo@chromium.org,ulan@chromium.org
>
> Change-Id: Ic83e4011148164ef080c63215a0c77f1dfb7f327
> Reviewed-on: https://chromium-review.googlesource.com/494487
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#45084}
TBR=ulan@chromium.org,rmcilroy@chromium.org,yangguo@chromium.org,jarin@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
BUG=v8:6246
Change-Id: Idab648d6fe260862c2a0e35366df19dcecf13a82
Reviewed-on: https://chromium-review.googlesource.com/498633
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45174}
Since the feedback vector is itself a native context structure, why
not store optimized code for a function in there rather than in
a map from native context to code? This allows us to get rid of
the optimized code map in the SharedFunctionInfo, saving a pointer,
and making lookup of any optimized code quicker.
Original patch by Michael Stanton <mvstanton@chromium.org>
BUG=v8:6246
TBR=yangguo@chromium.org,ulan@chromium.org
Change-Id: Ic83e4011148164ef080c63215a0c77f1dfb7f327
Reviewed-on: https://chromium-review.googlesource.com/494487
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45084}
This reverts commit c5ad9c6d8e.
Reason for revert: Fails on gc stress:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20GC%20Stress%20-%20custom%20snapshot/builds/12661
Original change's description:
> [TypeFeedbackVector] Store optimized code in the vector
>
> Since the feedback vector is itself a native context structure, why
> not store optimized code for a function in there rather than in
> a map from native context to code? This allows us to get rid of
> the optimized code map in the SharedFunctionInfo, saving a pointer,
> and making lookup of any optimized code quicker.
>
> Original patch by Michael Stanton <mvstanton@chromium.org>
>
> BUG=v8:6246
>
> Change-Id: I60ff8c408c3001bc272b4b198c9cbaea2872a9e5
> Reviewed-on: https://chromium-review.googlesource.com/476891
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Reviewed-by: Michael Stanton <mvstanton@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#45022}
TBR=ulan@chromium.org,rmcilroy@chromium.org,yangguo@chromium.org,mvstanton@chromium.org,jarin@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:6246
Change-Id: I9cd5735b03898cae6ae7adea0f19d32fceb31619
Reviewed-on: https://chromium-review.googlesource.com/493287
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45027}
Since the feedback vector is itself a native context structure, why
not store optimized code for a function in there rather than in
a map from native context to code? This allows us to get rid of
the optimized code map in the SharedFunctionInfo, saving a pointer,
and making lookup of any optimized code quicker.
Original patch by Michael Stanton <mvstanton@chromium.org>
BUG=v8:6246
Change-Id: I60ff8c408c3001bc272b4b198c9cbaea2872a9e5
Reviewed-on: https://chromium-review.googlesource.com/476891
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45022}
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}
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}
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}
The original peephole optimizer logic in the BytecodeArrayBuilder did
not respect source positions as it was written before there were
bytecode source positions. This led to some minor differences to
FCG and was problematic when combined with pending bytecode
optimizations. This change makes the new peephole optimizer fully
respect source positions.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/1998203002
Cr-Commit-Position: refs/heads/master@{#36439}
This change introduces a pipeline for the final stages of
bytecode generation.
The peephole optimizer is made distinct from the BytecodeArrayBuilder.
A new BytecodeArrayWriter is responsible for writing bytecode. It
also keeps track of the maximum register seen and offers a potentially
smaller frame size.
R=rmcilroy@chromium.org
LOG=N
BUG=v8:4280
Review-Url: https://codereview.chromium.org/1947403002
Cr-Commit-Position: refs/heads/master@{#36220}
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}
This change introduces wide prefix bytecodes to support wide (16-bit)
and extra-wide (32-bit) operands. It retires the previous
wide-bytecodes and reduces the number of operand types.
Operands are now either scalable or fixed size. Scalable operands
increase in width when a bytecode is prefixed with wide or extra-wide.
The bytecode handler table is extended to 256*3 entries. The
first 256 entries are used for bytecodes with 8-bit operands,
the second 256 entries are used for bytecodes with operands that
scale to 16-bits, and the third group of 256 entries are used for
bytecodes with operands that scale to 32-bits.
LOG=N
BUG=v8:4747,v8:4280
Review URL: https://codereview.chromium.org/1783483002
Cr-Commit-Position: refs/heads/master@{#34955}
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}
