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}
In edge cases such as the following, sloppy-mode block-scoped function
hoisting is expected to occur:
eval(`
with({a: 1}) {
function a() {}
}
`)
In this case, there should be the equivalent of a var declaration
outside of the eval, which gets set to the value of the local function
a when the body of the with is executed.
Previously, the way that var declarations are hoisted out of eval
meant that the assignment to that var was an ordinary DYNAMIC_GLOBAL
assignment. However, such a lookup mode meant that the object in the
with scope received the assignment!
This patch fixes that error by marking the assignments produced by
the sloppy mode block scoped function hoisting desugaring so as to
generate a different runtime call which skips with scopes.
Bug: chromium:720247, v8:5135
Change-Id: Ie36322ddc9ca848bf680163e8c016f50d4597748
Reviewed-on: https://chromium-review.googlesource.com/529230
Commit-Queue: Daniel Ehrenberg <littledan@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46116}
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}
Adds a collection of call bytecodes which have an implicit undefined
receiver argument, for cases such as global calls where we know that the
receiver has to be undefined. This way we can skip an LdaUndefined,
decrease bytecode register pressure, and set a more accurate
ConvertReceiverMode on the interpreter and TurboFan call.
As a side effect, the "normal" Call bytecode now becomes a rare case
(only with calls and super property calls), so we get rid of its 0-2
argument special cases and modify CallProperty[N] to use the
NotNullOrUndefined ConvertReceiverMode.
Reland of https://chromium-review.googlesource.com/c/463287 after fixing
tests in https://codereview.chromium.org/2813873002.
Change-Id: I314d69c7643ceec6a5750ffdab60dad38dad09e5
Reviewed-on: https://chromium-review.googlesource.com/474752
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44582}
This reverts commit 751e893591.
Reason for revert: Breaks layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/14885
See:
https://github.com/v8/v8/wiki/Blink-layout-tests
Original change's description:
> [ignition] Add call bytecodes for undefined receiver
>
> Adds a collection of call bytecodes which have an implicit undefined
> receiver argument, for cases such as global calls where we know that the
> receiver has to be undefined. This way we can skip an LdaUndefined,
> decrease bytecode register pressure, and set a more accurate
> ConvertReceiverMode on the interpreter and TurboFan call.
>
> As a side effect, the "normal" Call bytecode now becomes a rare case
> (only with calls and super property calls), so we get rid of its 0-2
> argument special cases and modify CallProperty[N] to use the
> NotNullOrUndefined ConvertReceiverMode.
>
> Change-Id: I9374a32fefd66fc0251b5193bae7a6b7dc31eefc
> Reviewed-on: https://chromium-review.googlesource.com/463287
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#44530}
TBR=rmcilroy@chromium.org,mstarzinger@chromium.org,leszeks@chromium.org,v8-reviews@googlegroups.com,v8-mips-ports@googlegroups.com,v8-ppc-ports@googlegroups.com,v8-x87-ports@googlegroups.com,bmeurer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Change-Id: I7629dec609d0ec938ce7105d6c1c74884e5f9272
Reviewed-on: https://chromium-review.googlesource.com/474744
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44548}
Adds a collection of call bytecodes which have an implicit undefined
receiver argument, for cases such as global calls where we know that the
receiver has to be undefined. This way we can skip an LdaUndefined,
decrease bytecode register pressure, and set a more accurate
ConvertReceiverMode on the interpreter and TurboFan call.
As a side effect, the "normal" Call bytecode now becomes a rare case
(only with calls and super property calls), so we get rid of its 0-2
argument special cases and modify CallProperty[N] to use the
NotNullOrUndefined ConvertReceiverMode.
Change-Id: I9374a32fefd66fc0251b5193bae7a6b7dc31eefc
Reviewed-on: https://chromium-review.googlesource.com/463287
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44530}
Specifically, add bytecodes for Call0, Call1, Call2, CallProperty0, CallProperty1,
and CallProperty2. Also share the bytecode handler code between between
equivalent CallX and CallPropertyX handlers.
Review-Url: https://codereview.chromium.org/2684993002
Cr-Original-Commit-Position: refs/heads/master@{#43290}
Committed: 00d6f1f80a
Review-Url: https://codereview.chromium.org/2684993002
Cr-Commit-Position: refs/heads/master@{#43700}
Reason for revert:
Due to arm64 failures
Original issue's description:
> [interpreter] Create custom call opcodes for specific argument counts
>
> Specifically, add bytecodes for Call0, Call1, Call2, CallProperty0, CallProperty1,
> and CallProperty2. Also share the bytecode handler code between between
> equivalent CallX and CallPropertyX handlers.
>
> Review-Url: https://codereview.chromium.org/2684993002
> Cr-Commit-Position: refs/heads/master@{#43290}
> Committed: 00d6f1f80aTBR=rmcilroy@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
Review-Url: https://codereview.chromium.org/2709533002
Cr-Commit-Position: refs/heads/master@{#43308}
Specifically, add bytecodes for Call0, Call1, Call2, CallProperty0, CallProperty1,
and CallProperty2. Also share the bytecode handler code between between
equivalent CallX and CallPropertyX handlers.
Review-Url: https://codereview.chromium.org/2684993002
Cr-Commit-Position: refs/heads/master@{#43290}
This removes the POSSIBLY_EVAL_CALL call type, and instead uses OTHER_CALL
or WITH_CALL to decide whether to do the special LOOKUP_SLOT_CALL runtime
call to find the callee and possibly update the receiver with the with-object.
This means that eval calls out of 'with' blocks can now just do a normal
LdaLookupGlobalSlot operation, which can check the context chain for eval
extentions and fast-path the lookup if none exist.
BUG=661556
Review-Url: https://codereview.chromium.org/2487483004
Cr-Commit-Position: refs/heads/master@{#40965}
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}
Consistently collect CallIC feedback in fullcodegen and Ignition, even
for possibly direct eval calls, that were treated specially so far, for
no apparent reason. With the upcoming SharedFunctionInfo based CallIC
feedback, we might be able to even inline certain direct eval calls, if
they manage to hit the eval cache. More importantly, this patch
simplifies the collection and dealing with CallIC feedback (and as a
side effect fixes an inconsistency with feedback for super constructor
calls).
R=mvstanton@chromium.org, mythria@chromium.org
BUG=v8:2206,v8:4280,v8:5267
Review-Url: https://codereview.chromium.org/2426693002
Cr-Commit-Position: refs/heads/master@{#40397}
There are only a few occasions where we allocate a register in an outer
expression allocation scope, which makes the costly free-list approach
of the BytecodeRegisterAllocator unecessary. This CL replaces all
occurrences with moves to the accumulator and stores to a register
allocated in the correct scope. By doing this, we can simplify the
BytecodeRegisterAllocator to be a simple bump-pointer allocator
with registers released in the same order as allocated.
The following changes are also made:
- Make BytecodeRegisterOptimizer able to use registers which have been
unallocated, but not yet reused
- Remove RegisterExpressionResultScope and rename
AccumulatorExpressionResultScope to ValueExpressionResultScope
- Introduce RegisterList to represent consecutive register
allocations, and use this for operands to call bytecodes.
By avoiding the free-list handling, this gives another couple of
percent on CodeLoad.
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2369873002
Cr-Commit-Position: refs/heads/master@{#39905}
Adds a fast path for loading DYNAMIC_GLOBAL variables, which are lookup
variables that can be globally loaded, without calling the runtime, as long as
there was no context extension by a sloppy eval along their context chain.
BUG=v8:5263
Review-Url: https://codereview.chromium.org/2347143002
Cr-Commit-Position: refs/heads/master@{#39537}
Adds a fast path for loading DYNAMIC_LOCAL variables, which are lookup
variables that can be context loaded, without calling the runtime, as
long as there was no context extension by a sloppy eval along their
context chain.
BUG=v8:5263
Review-Url: https://codereview.chromium.org/2343633002
Cr-Commit-Position: refs/heads/master@{#39473}
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}
Lexically declared "arguments" in sloppy mode will throw redeclaration error
currently, this patch fixes it by delaying the declaration of arguments until we
fully parse parameter list and function body.
BUG=v8:4577
LOG=N
Committed: https://crrev.com/70a613dd0a5f5d205b46559b55702764464851fa
Review-Url: https://codereview.chromium.org/2290753003
Cr-Original-Commit-Position: refs/heads/master@{#39109}
Cr-Commit-Position: refs/heads/master@{#39230}
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}
Reason for revert:
Breaks layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/9470
Original issue's description:
> Allow lexically declared "arguments" in function scope in sloppy mode.
>
> Lexically declared "arguments" in sloppy mode will throw redeclaration error
> currently, this patch fixes it by delaying the declaration of arguments until we
> fully parse parameter list and function body.
>
> BUG=v8:4577
> LOG=N
>
> Committed: https://crrev.com/70a613dd0a5f5d205b46559b55702764464851fa
> Cr-Commit-Position: refs/heads/master@{#39109}
TBR=adamk@chromium.org,mythria@chromium.org,lpy@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4577
Review-Url: https://codereview.chromium.org/2304853002
Cr-Commit-Position: refs/heads/master@{#39115}
Lexically declared "arguments" in sloppy mode will throw redeclaration error
currently, this patch fixes it by delaying the declaration of arguments until we
fully parse parameter list and function body.
BUG=v8:4577
LOG=N
Review-Url: https://codereview.chromium.org/2290753003
Cr-Commit-Position: refs/heads/master@{#39109}
Add a new bytecode to create a function context. The handler inlines
FastNewFunctionContextStub.
BUG=v8:4280
LOG=n
Review-Url: https://codereview.chromium.org/2187523002
Cr-Commit-Position: refs/heads/master@{#38301}
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}
Reason for revert:
performance impact
Original issue's description:
> Correctly annotate eval origin.
>
> There were a couple of issues with it:
> - interpreter is not supported
> - the source position was just accidentally correct for full-codegen
> - the eval origin could have been cached
>
> Also fixes a few other places to use AbstractCode.
>
> R=mstarzinger@chromium.org
>
> Committed: https://crrev.com/2f3a171adc9e620c2235bf0562145b9d4eaba66d
> Cr-Commit-Position: refs/heads/master@{#35257}
>
> Committed: https://crrev.com/ad4e8a27963b704bb70ec8bac0991c57296b1d16
> Cr-Commit-Position: refs/heads/master@{#35481}
TBR=mstarzinger@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/1888013002
Cr-Commit-Position: refs/heads/master@{#35491}
There were a couple of issues with it:
- interpreter is not supported
- the source position was just accidentally correct for full-codegen
- the eval origin could have been cached
Also fixes a few other places to use AbstractCode.
R=mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/1854713002
Cr-Commit-Position: refs/heads/master@{#35257}
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}
