Commit Graph

66 Commits

Author SHA1 Message Date
Ryan Macnak 7b2c672c8a [vm] Short-circuit disassembly instead of disassembling into the no-op log.
Avoids a bunch of work in the kernel and service isolates when running with --disassemble and the default --isolate-log-filter.

TEST=vm/dart/disassemble_determinism_test
Bug: https://github.com/dart-lang/sdk/issues/55421
Change-Id: Ic5da9b83ffaa3949074561aad8654ee11c041051
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/362164
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2024-04-10 23:09:37 +00:00
Ryan Macnak 688917045f [vm] Use AT_HWCAP instead of /proc/cpuinfo for most ARM feature detection.
Under user-space emulation or 32-bit ARM on a 64-bit ARM system, /proc/cpuinfo describes the host CPU instead of the emulated ARM CPU.

Also fix the encoding of sdiv. Apparently QEMU is stricter than hardware.

TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/29270
Bug: https://github.com/dart-lang/sdk/issues/54909
Change-Id: Icadf1a276e468dbb8142da49f961f33bca499d27
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/352680
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2024-02-15 23:08:48 +00:00
Tess Strickland fc613d85a7 [vm] Respect PC offset printing options for disassembled function info.
When disassembling functions, respect whether absolute addresses should
be used for PC offsets when printing stack map, PC descriptor and
exception handler information.

Also don't print out results for empty auxiliary information.

TEST=ci

Change-Id: Ieda990c1eabcce8be968981a81123a78746c6b6b
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/336663
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2023-11-21 12:23:52 +00:00
Ryan Macnak 5941defa81 [vm] Update to constexpr in runtime/vm/compiler.
TEST=build
Change-Id: Idf0a05cf8c27164834b5d8464b230cd334a06835
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/293082
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2023-04-11 21:50:56 +00:00
Ryan Macnak de2abc6091 [vm] Update NULL to nullptr in runtime/vm/compiler.
TEST=build
Change-Id: I54cd75bbc942e11c4d719edcc64640da67077634
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/291965
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2023-03-30 18:23:53 +00:00
Vyacheslav Egorov 7e82a87658 [vm/compiler] Cleanup IL dumps a bit
* Do not print redundant ParallelMove instructions unless
  `--print_redundant_il` is specified.
* Do not print `;; Inlined` comments if
  `--no_include_inlining_info_in_disassembly` is specified.

TEST=manually

Change-Id: I9a8c83514e2a749484863a4cc010c8ea7950b0fb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/278748
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2023-01-11 15:51:55 +00:00
Ryan Macnak 1cdc606ab3 [vm, compiler] Include the global object pool in AOT's --disassemble.
TEST=--disassemble
Change-Id: Iabb8017bccb72fc6acbdcf0abaf35569d034de8c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/244560
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2022-05-12 17:38:35 +00:00
Vyacheslav Egorov 47ec77122a [vm] Improve crash reporting for gen_snapshot
* Use CompilerPass::GenerateCode in AOT to ensure we print
the graph if the code generation crashes.
* Enable Dart_DumpNativeStackTrace in gen_snapshot even in
PRODUCT builds.

Additionally enable disassembler in gen_snapshot even in
PRODUCT builds.

TEST=tested manually

Change-Id: I951d62ca07c7882fa1d8e765d4b5ffd26edd9456
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/233880
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Auto-Submit: Slava Egorov <vegorov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
2022-03-11 09:20:36 +00:00
Ryan Macnak e54d75203e [vm] Fix crash when using --disassemble with AOT snapshots.
Broken by 13d27d669d.

TEST=disassemble_aot_test
Change-Id: I015c7b9d8cdf8d30a70595604799c790ef758bb2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/233528
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2022-02-23 20:49:03 +00:00
Ryan Macnak 04ba20aa98 [vm] Support RISC-V.
Implements a backend targeting RV32GC and RV64GC, based on Linux standardizing around GC. The assembler is written to make it easy to disable usage of C, but because the sizes of some instruction sequences are compile-time constants, an additional build configuration would need to be defined to make use of it.

The assembler and disassembler cover every RV32/64GC instruction. The simulator covers all instructions except accessing CSRs and the floating point state accessible through such, include accrued exceptions and dynamic rounding mode.

Quirks:
  - RISC-V is a compare-and-branch architecture, but some existing "architecture-independent" parts of the Dart compiler assume a condition code architecture. To avoid rewriting these parts, we use a peephole in the assembler to map to compare-and-branch. See Assembler::BranchIf. Luckily nothing depended on taking multiple branches on the same condition code set.
  - There are no hardware overflow checks, so we must use Hacker's Delight style software checks. Often these are very cheap: if the sign of one operand is known, a single branch is needed.
  - The ranges of RISC-V branches and jumps are such that we use 3 levels of generation for forward branches, instead of the 2 levels of near and far branches used on ARM[64]. Nearly all code is handled by the first two levels with 20-bits of range, with enormous regex matchers triggering the third level that uses aupic+jalr to get 32-bits of range.
  - For PC-relative calls in AOT, we always generate auipc+jalr pairs with 32-bits of range, so we never generate trampolines.
  - Only a subset of registers are available in some compressed instructions, so we assign the most popular uses to these registers. In particular, THR, TMP[2], CODE and PP. This has the effect of assigning CODE and PP to volatile registers in the C calling convention, whereas they are assigned preserved registers on the other architectures. As on ARM64, PP is untagged; this is so short indices can be accessed with a compressed instruction.
  - There are no push or pop instructions, so combining pushes and pops is preferred so we can update SP once.
  - The C calling convention has a strongly aligned stack, but unlike on ARM64 we don't need to use an alternate stack pointer. The author ensured language was added to the RISC-V psABI making the OS responsible for realigning the stack pointer for signal handlers, allowing Dart to leave the stack pointer misaligned from the C calling convention's point of view until a foreign call.
  - We don't bother with the link register tracking done on ARM[64]. Instead we make use of an alternate link register to avoid inline spilling in the write barrier.

Unimplemented:
 - non-trivial FFI cases
 - Compressed pointers - No intention to implement.
 - Unboxed SIMD - We might make use of the V extension registers when the V extension is ratified.
 - BigInt intrinsics

TEST=existing tests for IL level, new tests for assembler/disassembler/simulator
Bug: https://github.com/dart-lang/sdk/issues/38587
Bug: https://github.com/dart-lang/sdk/issues/48164
Change-Id: I991d1df4be5bf55efec5371b767b332d37dfa3e0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/217289
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2022-01-20 00:57:57 +00:00
Vyacheslav Egorov 13d27d669d [vm] Improve Code cluster layout for startup
This change bakes binary search table which maps PC ranges
to corresponding stack maps and Code objects (if still present
in the snapshot) into RO data section of the snapshot - instead
of constructing it at load time.

This allows to considerably reduce amount of work done when
loading Code cluster for programs which have majority of their
Code objects discarded (i.e. in DWARF stack traces mode): as
we no longer write / read any information for discarded Code
objects.

This CL also changes program visitor to deduplicate Code objects
if their instructions are deduplicated in AOT mode. Only a single
Code object can be choose as a representative for the given
PC range so it does not make sense to write multiple Code objects
into the snapshot which refer to the same Instructions.

The overall improvement is hard to quantify but ReadProgramSnapshot
shows the following improvement when starting a large
Flutter application on a slow Android device:

  before  223.55±59.94 (192.02 .. 391.74) ms
  after   178.06±47.03 (151.31 .. 291.34) ms

This CL packs CompressedStackMaps next to the binary search table
itself allowing us to address them via offsets instead of
pointers.

Snapshot sizes are actually affected positively by this change. On
the same large Flutter application I see

  DWARF stack traces on:  -1.34% total SO size
  DWARF stack traces off: -1.63% total SO size

Issue https://github.com/dart-lang/sdk/issues/46116

TEST=ci

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-dwarf-linux-product-x64-try,vm-kernel-precomp-linux-debug-simarm64c-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm_x64-try,vm-kernel-precomp-linux-release-x64-try
Change-Id: Ic997045a33daa81ec68df462a0792915885df66b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/220766
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
2021-12-16 10:39:49 +00:00
Ryan Macnak 4b2309c15a [standalone] Fix reuse of va_list in syslog_android.cc.
Also add some missing va_end.

TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/47939
Change-Id: Iadfbf72493d987dfb1d102922db1b353249a4728
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/224240
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2021-12-15 22:22:36 +00:00
Vyacheslav Egorov 71c9c2cd83 [vm] Remove support for non-bare AOT snapshots
Every AOT user out there has been using bare instructions mode
and continuing to maintaining non-bare instructions mode simply
adds costs (both in terms of time spent making changes to work
in a mode that is not used and CI resources spent on testing it).

This change removes FLAG_use_bare_instructions and changes the code
to assume that FLAG_precompiled_mode implies bare instructions.

TEST=ci

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-dwarf-linux-product-x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,app-kernel-linux-release-x64-try,app-kernel-linux-debug-x64-try
Change-Id: I5032b13bfcb613f79865f2cfa139cca8d1b42556
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/220964
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2021-11-24 13:03:52 +00:00
Tess Strickland e7d3a6027c [vm] Create more Function helper methods for code clarity.
Creates HasParent() as a predicate for Function objects with a non-null
parent function and makes IsLocalFunction() specific to local closures
(i.e. explicit closures with non-null parent functions).

Creates HasSavedArgumentsDescriptor() as a predicate to determine when
saved_args_desc() can be used, to avoid the caller having to do explicit
predicate checks for each dispatcher type that contains one.

Also simplifies Function::PrintName, creates different suffixes for a
SyncGenClosureMaker and its associateed SyncGenClosure, adds suffixes
for skipping more than one generated body when printing the parent name,
and changes ArgumentsDescriptor::PrintTo to match the compact syntax
Function::PrintName used for signifying the arguments descriptor for
certain dispatchers.

TEST=pkg/vm_snapshot_analysis/test/instruction_sizes_test

Cq-Include-Trybots: luci.dart.try:app-kernel-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,pkg-linux-release-try
Change-Id: I0ac1226d1ffe1d81743b5c6788da170d5a4010c5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/191560
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2021-03-23 12:21:26 +00:00
Alexander Markov ddfc98337b Reland "[vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces"
This is a reland of b6dc4dad4d

TEST=ci

Original change's description:
> [vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces
>
> The following changes are done in preparation for the removal of Code
> objects in AOT with --dwarf-stack-traces:
>
> * Stack trace objects are extended to hold uword PCs (which may not
>   fit into Smi range).
>
> * Scanning stack frames in GC (StackFrame::VisitObjectPointers)
>   now avoids using Code objects.
>   In order to find CompressedStackMaps it now calls
>   ReversePc::FindCompressedStackMaps.
>
> * Singleton Code object (StubCode::UnknownDartCode()) is prepared as
>   a replacement for Code objects in stack traces. It has
>   PayloadStart() == 0 and Size() == kUwordMax so it includes
>   arbitrary PCs.
>
> * In --dwarf-stack-traces mode, most Code objects obtained from stack
>   frames are replaced with StubCode::UnknownDartCode().
>   This simulates future behavior of ReversePc::Lookup when Code objects
>   will be removed.
>
> Issue: https://github.com/dart-lang/sdk/issues/44852
> Change-Id: I7cec7b8b9396c9cfeca3c256a412ba4e82a7e0c4
> TEST=ci
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182720
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
> Reviewed-by: Tess Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>

Change-Id: Ia2fc4672a085cd963b7fc103369851df3603590c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/186202
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2021-02-22 10:46:28 +00:00
Alexander Markov fde0ed2e93 Revert "[vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces"
This reverts commit b6dc4dad4d.

Reason for revert: broke package:vm_snapshot_analysis in Flutter
(https://github.com/flutter/flutter/issues/76313).

Original change's description:
> [vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces
>
> The following changes are done in preparation for the removal of Code
> objects in AOT with --dwarf-stack-traces:
>
> * Stack trace objects are extended to hold uword PCs (which may not
>   fit into Smi range).
>
> * Scanning stack frames in GC (StackFrame::VisitObjectPointers)
>   now avoids using Code objects.
>   In order to find CompressedStackMaps it now calls
>   ReversePc::FindCompressedStackMaps.
>
> * Singleton Code object (StubCode::UnknownDartCode()) is prepared as
>   a replacement for Code objects in stack traces. It has
>   PayloadStart() == 0 and Size() == kUwordMax so it includes
>   arbitrary PCs.
>
> * In --dwarf-stack-traces mode, most Code objects obtained from stack
>   frames are replaced with StubCode::UnknownDartCode().
>   This simulates future behavior of ReversePc::Lookup when Code objects
>   will be removed.
>
> Issue: https://github.com/dart-lang/sdk/issues/44852
> Change-Id: I7cec7b8b9396c9cfeca3c256a412ba4e82a7e0c4
> TEST=ci
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182720
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
> Reviewed-by: Tess Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>

Issue: https://github.com/dart-lang/sdk/issues/44852
Change-Id: I6f66171eecf1133363a7ce56193e782e43a20baf
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185488
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
2021-02-18 18:04:29 +00:00
Alexander Markov b6dc4dad4d [vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces
The following changes are done in preparation for the removal of Code
objects in AOT with --dwarf-stack-traces:

* Stack trace objects are extended to hold uword PCs (which may not
  fit into Smi range).

* Scanning stack frames in GC (StackFrame::VisitObjectPointers)
  now avoids using Code objects.
  In order to find CompressedStackMaps it now calls
  ReversePc::FindCompressedStackMaps.

* Singleton Code object (StubCode::UnknownDartCode()) is prepared as
  a replacement for Code objects in stack traces. It has
  PayloadStart() == 0 and Size() == kUwordMax so it includes
  arbitrary PCs.

* In --dwarf-stack-traces mode, most Code objects obtained from stack
  frames are replaced with StubCode::UnknownDartCode().
  This simulates future behavior of ReversePc::Lookup when Code objects
  will be removed.

Issue: https://github.com/dart-lang/sdk/issues/44852
Change-Id: I7cec7b8b9396c9cfeca3c256a412ba4e82a7e0c4
TEST=ci
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182720
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2021-02-17 20:12:32 +00:00
Vyacheslav Egorov d7a57a5df4 [vm] Add feature to connect AOT code to code comments via .debug_line
Option --write_code_comments_as_synthetic_source_to=file tells AOT
compiler to create a file which contains code comments for all code
objects written into an ELF snapshot and then emit a DWARF line number
program into .debug_line section which attributes code to code comments
in a way similar to how our own disassembler does it.

This enables tools like objdump to display our code comments as part of
the disassembly.

This CL also tweaks ifdefs in such a way that IL printer and code comments
facilities is now included into PRODUCT gen_snapshot binary.

TEST=manually run product build with --print-flow-graph and --write_code_comments_as_synthetic_source_to

Change-Id: Id6741013d43e1733b4ddeb34891a4d2fc06b9313
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/181380
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2021-02-02 11:35:00 +00:00
Ryan Macnak b1c09ecd8f [vm] Make naming more consistent when converting between handles, tagged and untagged pointers.
Currently we have things called XPtr which are not what you get from ptr().

Old world:
handle->raw() returns RawObject* (tagged)
raw_obj->ptr() returns RawObject* (untagged)

After 6fe15f6df9:
handle->raw() returns ObjectPtr
obj_ptr->ptr() returns ObjectLayout*

New world:
handle->ptr() returns ObjectPtr
obj_ptr->untag() returns UntaggedObject*

TEST=ci
Change-Id: I6c7f34014cf20737607caaf84979838300d12df2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149367
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2021-01-15 23:32:02 +00:00
Tess Strickland e2df4d30a0 [vm] Remove non-private uses of TokenPosition::value().
Instead, split each old use into the following cases:

* If the TokenPosition value is expected to be a real token position,
  then use TokenPosition::Pos().

* If the TokenPosition is being serialized in some way, then use
  TokenPosition::Serialize() and change the place where the
  TokenPosition is recreated to use TokenPosition::Deserialize().

* If the value of the TokenPosition is being printed for debugging
  purposes, then just use TokenPosition::ToCString() instead.

That is, we try to pin down when token positions are expected to
be real vs. when other types of token positions can be found.

Another source of possible error when using token positions is to
convert between synthetic and real token positions. In the past,
synthetic token positions may have been based off real token positions,
but that is no longer the case. Thus, all methods that allow
that conversion have been removed, and instead there is a new static
method for constructing synthetic tokens from valid nonces.

This CL also makes it so that Pos() and relational operators on token
positions are only defined on real token positions, to avoid any
assumptions about what the value encoded in synthetic positions mean. To
help with cases where non-real token positions may occur, four helper
methods are added:

* TokenPosition::Min(a, b): A static method that returns the smallest
  real token position provided. If neither `a` or `b` are real,
  returns `a`.

* TokenPosition::Max(a, b): A static method that returns the largest
  real token position provided. If neither `a` or `b` are real,
  returns `a`.

* TokenPosition::IsWithin(start, end): Determines whether `this` falls
  between `start` and `end` (inclusive). If `this` is non-real, then it
  must be either `start` or `end` if synthetic, otherwise false.
  Otherwise, we mimic the old style of range checking, which means that
  non-real starts and ends are treated as less than every real token.

* TokenPosition::CompareForSorting(other): Unlike the relational
  operators, provides a comparison between any types of token positions
  for purposes such as sorting.  Currently only used in the profiler.

It also changes TokenPosition::ToCString() to tag synthetic token
positions, so they can be distinguished from real ones at a glance.

TEST=Existing test suite on trybots, especially the observatory tests
which make heavy use of the debugger and the unit tests for the
profiler/source report modules.

Bug: https://github.com/dart-lang/sdk/issues/44436

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-nnbd-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-nnbd-linux-debug-x64-try,vm-kernel-linux-debug-x64-try,vm-kernel-linux-release-x64-try,vm-kernel-nnbd-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-nnbd-linux-release-x64-try,vm-kernel-linux-product-x64-try,vm-kernel-precomp-linux-product-x64-try
Change-Id: Ic06aa0bc7a1f0fbac7257ed22ca5e7e0ccd7f3f2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/174924
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2020-12-16 08:27:32 +00:00
Tess Strickland 45a46ca2b8 [vm] Add (S)LEB128 encoding/decoding to BaseWriteStream.
Unlike cfc8e6de, this does _not_ replace the default variable length
encoding for {Read,Write}Streams, but insteads adds separate
{Read,Write}{S,}LEB128 methods to the appropriate classes. If we later
find the cause of the issues that led to the revert of cfc8e6de, it'll
be easy to switch over then.

Note that WriteLEB128 asserts that the value is non-negative if used
with a signed type (since negative values suggests that SLEB128 should
be used instead for minimal encoding).

Also removes the various other encoding and decoding methods for
(S)LEB128 across the codebase and changes those clients to use
{Read,Write}Streams instead.

Other cleanups:

* Various constant-related cleanups in datastream.h.

* Adds DART_FORCE_INLINE to ReadStream::ReadByte and uses it in the
  default variable length decoding methods for retrieving bytes
  from the stream instead of managing current_ by hand.

* Creates a canonical empty CompressedStackMaps instance and uses
  that instead of the null CompressedStackMaps instance in most cases.
  The only remaining (expected) use of the null CompressedStackMaps
  instance is for the global table in the object store when no global
  table exists (e.g., in JIT mode before any snapshotting).

* Moves CompressedStackMapsIterator from code_descriptors.h to an
  Iterator class within CompressedStackMaps in object.h (similar to
  PcDescriptors::Iterator), to limit friend declarations and because it
  conceptually makes more sense as part of CompressedStackMaps.

* Removed CompressedStackMaps::PayloadByte, since existing clients
  (CompressedStackMaps::Iterator, StackMapEntry in program_visitor.cc)
  are better served by just operating on the payload buffer directly
  (with appropriate NoSafepointScopes).

* WriteStreams no longer allocate their initial space on construction,
  but rather on the first write, so no allocation is performed by
  constructing a never-used WriteStream.

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-mac-debug-x64-try,vm-kernel-win-debug-x64-try,vm-kernel-win-debug-ia32-try,vm-kernel-precomp-win-release-x64-try,vm-kernel-ubsan-linux-release-x64-try,vm-kernel-tsan-linux-release-x64-try,vm-kernel-precomp-ubsan-linux-release-x64-try,vm-kernel-precomp-tsan-linux-release-x64-try,vm-kernel-precomp-msan-linux-release-x64-try,vm-kernel-precomp-asan-linux-release-x64-try,vm-kernel-msan-linux-release-x64-try,vm-kernel-asan-linux-release-x64-try
Change-Id: Ice63321abaa79157fbe9f230a864c8bba0e6dea9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/166421
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
2020-10-09 10:08:16 +00:00
Tess Strickland 9254a8ce91 [vm] Add PrintTo and ToCString to ArgumentsDescriptor.
Add information about the saved arguments descriptor for dispatcher
functions to Function::ToCString and information about both the
function kind and the saved arguments descriptor (when appropriate)
to the flow graph printer and the disassembler.

Change-Id: I41f5db2d80039cb397447eb9b9db47e60469b284
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/158007
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
2020-08-11 10:04:19 +00:00
Tess Strickland 09ddcece30 [vm] Make BufferFormatter also a subclass of BaseTextBuffer.
Change-Id: I4d2759ffa80c0106838ad0ddbc6dd086fddda1dd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/157742
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
2020-08-07 21:40:45 +00:00
Vyacheslav Egorov 45310394a6 [vm] Exclude class name from function name in instruction sizes json.
Issue https://github.com/dart-lang/sdk/issues/41249

Cq-Include-Trybots: luci.dart.try:pkg-linux-debug-try,pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: Idf2bb9c9d6392c7a95aa09a2cc1f2190adcf782d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/150522
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2020-06-10 10:18:37 +00:00
Ryan Macnak 2707880f1b [vm] Fix various UBSan failures.
Bug: https://github.com/dart-lang/sdk/issues/39427
Change-Id: I74e0eee623d88005fb2893d03e284a87daa09260
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/146696
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2020-05-07 19:40:18 +00:00
Vyacheslav Egorov d959f4290e [vm/compiler] Disambiguate Code names when emitting instruction sizes info.
Previously the output used scrubbed qualified names which hides some
of the information and causes names of various synthetic functions
collide. We change it to use internal qualified names instead and add
additional information for disambiguation:

- For functions this means adding a prefix for various synthetic
methods;
- For anonymous closures we add their token position;
- For types we prefix type parameters with their owner's name.

We also add a unit test covering parsing of
--print-instructions-sizes-to output.

As part of adding a test dart2native was changed to support passing
extra arguments to gen_snapshot binary.

Fixes https://github.com/dart-lang/sdk/issues/41137

Cq-Include-Trybots: luci.dart.try:pkg-linux-debug-try,pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: I299ab0fb5993c8af9b51246483608d1e65970d67
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/146581
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
2020-05-07 12:39:27 +00:00
Alexander Markov 994f454996 [vm/nnbd] Call field initializer from stubs for late instance fields
This change introduces 2 new stubs, InitLateInstanceField and
InitLateFinalInstanceField. Those stubs call field initializer
directly without going to runtime.

Fixes the regressions on Uri.pathSegments.easy and Uri.pathSegments.hard.normalized
benchmarks with NNBD SDK after https://dart-review.googlesource.com/c/sdk/+/143189.

Change-Id: I6bde7a98010ac1321a95eda8b0f125105f3993c4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/144807
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Liam Appelbe <liama@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-04-28 21:35:23 +00:00
Ryan Macnak 6fe15f6df9 [vm] Represent tagged pointers as C++ value types instead of C++ pointer types.
This works around bugs in UndefinedBehaviorSanitizer and Clang.

Bug: b/28638298
Change-Id: I6be595f9664516019d28017d24559583a1ae3a21
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/144354
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2020-04-25 05:21:27 +00:00
Martin Kustermann bc59a40918 [vm/compiler] Use PC-relative calls in AssertAssignable when calling TTS
Additionally the TTS itself will also use pc-relative tail-call to the
slow path.

This reduces AssertAssignable by 1 instruction and generated
type testing stubs by 2 instructions.

Flutter gallery total size:

  armv8: -0.3%
  armv7: -0.27%

Issue https://github.com/dart-lang/sdk/issues/41426

Change-Id: Ib29ff9afd1df4034c8fa47f66c80c22e226c0979
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142988
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Aske Simon Christensen <askesc@google.com>
2020-04-18 20:27:38 +00:00
Vyacheslav Egorov a41a1dc917 [vm/compiler] Split compiler sources out of normal VM sources.
Make them form its own source set (libdart_compiler) and completely exclude
them from AOT runtime targets.

Previously we had some inconsistencies, with some files were using
DART_PRECOMPILED_RUNTIME to fully or partially exclude either contents
from their headers or from implementation, while other files did nothing
and relied on linker to throw their contents away.

This change tries to address this inconsistency.

A follow up change would include a check in most compiler headers which
would prohibit to use them while building AOT runtime.

Change-Id: Ief11b11cbc518b301d3e93fce80580a31bbad151
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142993
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-04-16 22:59:03 +00:00
Martin Kustermann af4bd2719e [vm/compiler] Add support for PC-relative tail calls and use it in TailCallInstr
Flutter gallery total size:
  - armv7: -0.15%
  - armv8: -0.33%

Issue https://github.com/dart-lang/sdk/issues/41426

Change-Id: I99959de45f43ca0c892cea6382ee7252e9c4f764
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142841
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2020-04-15 14:10:53 +00:00
Vyacheslav Egorov 1ad4fcb154 [vm/compiler] Fix Mac builds and disassembler test.
This is follow up to 2cc824043d

TBR=sjindel@google.com

Change-Id: If955320b549b87287fdc1f9b9a715b1ca024224a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/137968
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
2020-03-02 21:01:54 +00:00
Vyacheslav Egorov 2cc824043d [vm/compiler] Ensure we emit catch entry move for receiver when it is captured
We have a special logic which excludes captured parameters from the catch
entry moves (assuming that they will be reloaded from the context). Because
this logic is well hidden it was not updated when we changed our handling of
the captured receiver in 078806851c

Fixes https://github.com/dart-lang/sdk/issues/40809
Fixes https://github.com/flutter/flutter/issues/47482

Change-Id: I2f036204c2ac3a18c6f91d9ccb664eaee729d426
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/137965
Reviewed-by: Samir Jindel <sjindel@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
2020-03-02 20:09:42 +00:00
Teagan Strickland e01457d138 Reland "[vm/aot] Remove object wrapping of bare instructions for AOT snapshots."
Now, when writing an AOT snapshot in bare instructions mode, only
the actual instructions in the RawInstructions payload are serialized
instead of the entire RawInstructions object.

Since there are no longer RawInstructions objects in these AOT
snapshots, we also change how Code objects are serialized. Instead
of just containing a reference to the RawInstructions object, we
serialize two pieces of information: where the instructions
payload for this Code object begins and whether there was a single
entry for the instructions payload. (To save space, the single
entry bit is serialized as the low order bit of the unchecked
offset, which was already being serialized).

While we also need the length of the instructions payload, we
approximate it for all but the last Code object by subtracting
the next Code object's payload start from this Code object's
payload start. For the last Code object, we assume it extends
to the end of the instructions image.

Changes on flutter gallery in release mode:
armv7: instructions size -2.70%, total size -1.73%
armv8: instructions size -6.04%, total size -3.63%

Fixes https://github.com/dart-lang/sdk/issues/38451.

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm_x64-try,vm-kernel-precomp-android-release-arm64-try,vm-kernel-precomp-android-release-arm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-precomp-win-release-x64-try
Change-Id: Ia0a5c4e5e47c956776dc62503da38ec55a143c04
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/134325
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-02-10 15:08:04 +00:00
Teagan Strickland bb24f98616 Revert "[vm/aot] Remove object wrapping of bare instructions for AOT snapshots."
This reverts commit 7475c637c3.

Reason for revert: Breakage on simarm_x64 (and thus arm_x64)

Original change's description:
> [vm/aot] Remove object wrapping of bare instructions for AOT snapshots.
> 
> Now, when writing an AOT snapshot in bare instructions mode, only
> the actual instructions in the RawInstructions payload are serialized
> instead of the entire RawInstructions object.
> 
> Since there are no longer RawInstructions objects in these AOT
> snapshots, we also change how Code objects are serialized. Instead
> of just containing a reference to the RawInstructions object, we
> serialize two pieces of information: where the instructions
> payload for this Code object begins and whether there was a single
> entry for the instructions payload. (To save space, the single
> entry bit is serialized as the low order bit of the unchecked
> offset, which was already being serialized).
> 
> While we also need the length of the instructions payload, we
> approximate it for all but the last Code object by subtracting
> the next Code object's payload start from this Code object's
> payload start. For the last Code object, we assume it extends
> to the end of the instructions image.
> 
> Changes on flutter gallery in release mode:
> armv7: instructions size -2.66%, total size -1.68%
> armv8: instructions size -5.81%, total size -3.49%
> 
> Fixes https://github.com/dart-lang/sdk/issues/38451.
> 
> Change-Id: Ia458e8d99bae18f5c3b6e849df2519027f06f574
> Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm_x64-try,vm-kernel-precomp-android-release-arm64-try,vm-kernel-precomp-android-release-arm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-precomp-win-release-x64-try
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131067
> Commit-Queue: Teagan Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>

TBR=kustermann@google.com,rmacnak@google.com,sstrickl@google.com

Change-Id: If2c8ca6b0993211b2509b275af7ff11a8fa2baa3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-release-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-linux-release-simarm_x64-try, vm-kernel-precomp-android-release-arm64-try, vm-kernel-precomp-android-release-arm_x64-try, vm-kernel-precomp-mac-release-simarm64-try, vm-kernel-precomp-win-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/134322
Reviewed-by: Teagan Strickland <sstrickl@google.com>
Commit-Queue: Teagan Strickland <sstrickl@google.com>
2020-02-04 17:32:28 +00:00
Teagan Strickland 7475c637c3 [vm/aot] Remove object wrapping of bare instructions for AOT snapshots.
Now, when writing an AOT snapshot in bare instructions mode, only
the actual instructions in the RawInstructions payload are serialized
instead of the entire RawInstructions object.

Since there are no longer RawInstructions objects in these AOT
snapshots, we also change how Code objects are serialized. Instead
of just containing a reference to the RawInstructions object, we
serialize two pieces of information: where the instructions
payload for this Code object begins and whether there was a single
entry for the instructions payload. (To save space, the single
entry bit is serialized as the low order bit of the unchecked
offset, which was already being serialized).

While we also need the length of the instructions payload, we
approximate it for all but the last Code object by subtracting
the next Code object's payload start from this Code object's
payload start. For the last Code object, we assume it extends
to the end of the instructions image.

Changes on flutter gallery in release mode:
armv7: instructions size -2.66%, total size -1.68%
armv8: instructions size -5.81%, total size -3.49%

Fixes https://github.com/dart-lang/sdk/issues/38451.

Change-Id: Ia458e8d99bae18f5c3b6e849df2519027f06f574
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm_x64-try,vm-kernel-precomp-android-release-arm64-try,vm-kernel-precomp-android-release-arm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-precomp-win-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131067
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-02-04 10:28:43 +00:00
Samir Jindel d0909e068a Reland "[vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object."
This reverts commit 5f81efb4a3.

Reason for revert: 3xH bot is green again.

Original change's description:
> Revert "[vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object."
> 
> This reverts commit ab2026af45.
> 
> Reason for revert: Flutter 3xH is broken on Golem.
> 
> Original change's description:
> > [vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object.
> > 
> > Flutter Gallery ARMv8: -0.8% total, -1.3% instructions
> > Flutter Gallery ARMv7: -0.7% total, -1.2% instructions
> > 
> > There are some performance regressions, in four categories:
> > 
> > 1. Arithmetic on num types (e.g. MinLib, MaxLib):
> >    We believe arithmetic on num types is rare in practice, and can be optimized later
> >    by specializing the call-sites.
> > 
> > 2. Lack of types (e.g. MeshDecompression, ImagingGaussianBlur, Crypto*):
> >    These (and similar benchmarks) are written in a very untyped style, which is not
> >    representative of Dart 2 style. We've confirmed that the regressions disappear if
> >    the benchmarks are annotated with appropriate types.
> > 
> > 3. Megamorphic calls which are specialized in the benchmark (e.g. DeltaBlue):
> >    DeltaBlue uses string interpolation in one place, so the toString() method in the
> >    string interpolation helper is monomorphic for _Smis. However, in a realistic programs,
> >    string interpolation is used much more frequently and with different types, so it's very
> >    unlikely that this call would be monomorphic. When string interpolation is removed, there's
> >    a remaining 1.3% regression on DeltaBlue which is not yet accounted for.
> > 
> > 4. Noisy benchmarks
> >    The remaining regressions are on benchmarks which show frequent jitter historically.
> > 
> > There are also 1-4% improvements on many benchmarks (Golem's "noise" analysis is hiding
> > many of them, look at the graphs).
> > 
> > For the reasons above, we believe the regressions justified by the code size improvement.
> > 
> > Change-Id: Ic9b281d4383a6111de9d6f44347976ffa61a6ca6
> > Cq-Include-Trybots:luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-bare-linux-release-simarm64-try
> > Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/128667
> > Commit-Queue: Samir Jindel <sjindel@google.com>
> > Reviewed-by: Ryan Macnak <rmacnak@google.com>
> > Reviewed-by: Martin Kustermann <kustermann@google.com>
> 
> TBR=kustermann@google.com,rmacnak@google.com,alexmarkov@google.com,sjindel@google.com
> 
> Change-Id: I411aae4b230f2a08146ad3bf3e7a10aa6592db0e
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-bare-linux-release-simarm64-try
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131660
> Reviewed-by: Samir Jindel <sjindel@google.com>
> Commit-Queue: Samir Jindel <sjindel@google.com>

TBR=kustermann@google.com,rmacnak@google.com,alexmarkov@google.com,sjindel@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I36e4e9d598033fcc934c2cdf5b061aa11255d3b2
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-bare-linux-release-simarm64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131837
Reviewed-by: Samir Jindel <sjindel@google.com>
Commit-Queue: Samir Jindel <sjindel@google.com>
2020-01-16 14:21:16 +00:00
Samir Jindel 5f81efb4a3 Revert "[vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object."
This reverts commit ab2026af45.

Reason for revert: Flutter 3xH is broken on Golem.

Original change's description:
> [vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object.
> 
> Flutter Gallery ARMv8: -0.8% total, -1.3% instructions
> Flutter Gallery ARMv7: -0.7% total, -1.2% instructions
> 
> There are some performance regressions, in four categories:
> 
> 1. Arithmetic on num types (e.g. MinLib, MaxLib):
>    We believe arithmetic on num types is rare in practice, and can be optimized later
>    by specializing the call-sites.
> 
> 2. Lack of types (e.g. MeshDecompression, ImagingGaussianBlur, Crypto*):
>    These (and similar benchmarks) are written in a very untyped style, which is not
>    representative of Dart 2 style. We've confirmed that the regressions disappear if
>    the benchmarks are annotated with appropriate types.
> 
> 3. Megamorphic calls which are specialized in the benchmark (e.g. DeltaBlue):
>    DeltaBlue uses string interpolation in one place, so the toString() method in the
>    string interpolation helper is monomorphic for _Smis. However, in a realistic programs,
>    string interpolation is used much more frequently and with different types, so it's very
>    unlikely that this call would be monomorphic. When string interpolation is removed, there's
>    a remaining 1.3% regression on DeltaBlue which is not yet accounted for.
> 
> 4. Noisy benchmarks
>    The remaining regressions are on benchmarks which show frequent jitter historically.
> 
> There are also 1-4% improvements on many benchmarks (Golem's "noise" analysis is hiding
> many of them, look at the graphs).
> 
> For the reasons above, we believe the regressions justified by the code size improvement.
> 
> Change-Id: Ic9b281d4383a6111de9d6f44347976ffa61a6ca6
> Cq-Include-Trybots:luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-bare-linux-release-simarm64-try
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/128667
> Commit-Queue: Samir Jindel <sjindel@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>

TBR=kustermann@google.com,rmacnak@google.com,alexmarkov@google.com,sjindel@google.com

Change-Id: I411aae4b230f2a08146ad3bf3e7a10aa6592db0e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-bare-linux-release-simarm64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131660
Reviewed-by: Samir Jindel <sjindel@google.com>
Commit-Queue: Samir Jindel <sjindel@google.com>
2020-01-14 14:58:45 +00:00
Samir Jindel ab2026af45 [vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object.
Flutter Gallery ARMv8: -0.8% total, -1.3% instructions
Flutter Gallery ARMv7: -0.7% total, -1.2% instructions

There are some performance regressions, in four categories:

1. Arithmetic on num types (e.g. MinLib, MaxLib):
   We believe arithmetic on num types is rare in practice, and can be optimized later
   by specializing the call-sites.

2. Lack of types (e.g. MeshDecompression, ImagingGaussianBlur, Crypto*):
   These (and similar benchmarks) are written in a very untyped style, which is not
   representative of Dart 2 style. We've confirmed that the regressions disappear if
   the benchmarks are annotated with appropriate types.

3. Megamorphic calls which are specialized in the benchmark (e.g. DeltaBlue):
   DeltaBlue uses string interpolation in one place, so the toString() method in the
   string interpolation helper is monomorphic for _Smis. However, in a realistic programs,
   string interpolation is used much more frequently and with different types, so it's very
   unlikely that this call would be monomorphic. When string interpolation is removed, there's
   a remaining 1.3% regression on DeltaBlue which is not yet accounted for.

4. Noisy benchmarks
   The remaining regressions are on benchmarks which show frequent jitter historically.

There are also 1-4% improvements on many benchmarks (Golem's "noise" analysis is hiding
many of them, look at the graphs).

For the reasons above, we believe the regressions justified by the code size improvement.

Change-Id: Ic9b281d4383a6111de9d6f44347976ffa61a6ca6
Cq-Include-Trybots:luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-bare-linux-release-simarm64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/128667
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-01-14 13:18:05 +00:00
Martin Kustermann addd5eea00 [vm/compiler] Consistently use pc-offsets of pointing to instruction after call in static calls table, to ensure unique offsets
The pc-relative calls were recorded with pc-offsets pointing to the start of the
call instruction, where as code-based calls were recorded with
pc-offsets pointing to the next instruction (i.e. return address).

This is inconsistent and caused us to hit an assert in
`Code::set_static_calls_target_table`. The assert was benign, but it is
good to maintain the uniqueness guarantee in the static calls table, so
we'll unify the encoding to use offsets to the instruction after the
call in both cases.

Closes https://github.com/dart-lang/sdk/issues/39811

Change-Id: Id0305befd78f09ed0b0e100f39641bca9e764442
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/129717
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
2020-01-03 17:17:59 +00:00
Teagan Strickland f6d433dc5e [vm] Remove the unchecked entry point offset field from RawInstructions.
There's just one case where we can't get the offset for Instructions
from somewhere else, and that's when we reset active_instructions_ to
instructions_ in Code::Enable(). Thus, we add a caching field for the
uncached offset to RawCode, but only when the active_instructions_
field is added (when not running in the precompiled runtime).

We also output the unchecked offset in snapshots for Code objects so
we can recalculate the entry point cache on loading. (For full JIT
snapshots, we output both the cached offset and the offset for
active_instructions_.)

Bug: https://github.com/dart-lang/sdk/issues/38451
Change-Id: I78572ec83d1574b00820df148bccb57e5c79eaaa
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/125400
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Teagan Strickland <sstrickl@google.com>
2019-12-11 10:00:29 +00:00
Clement Skau 28a029102b [SDK] Adds --support-disassembler in PRODUCT.
This CL also addes CodeSourceMap source positions to the disassembler output.

Change-Id: I49f6cb5257394badc8a005167f906e185509a3e7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/125663
Commit-Queue: Clement Skau <cskau@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-11-21 12:28:45 +00:00
Samir Jindel dd7760a07d [vm] Support disassembling snapshot code at runtime for JIT and AOT snapshots.
--code-comments should be passed both at compile/training-time and run-time to get
comments in the disassembled instructions.

The required --disassemble-* flags need only be passed at run-time. Flow-graph printing
is not yet supported because we don't save flow-graph like assembly comments.

This functionality is excluded from product builds.

Change-Id: If35fbb08cff6eae40069f916ecec9c6f589c0cad
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/124989
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-11-14 14:09:21 +00:00
Teagan Strickland c9f6e669f9 [vm/compiler] Reland "Further compress the information... in StackMaps."
Fixes an assumption that CompressedStackMapsIterator::Find() is never
passed a PC offset of 0. Adds back an ASSERT that was dropped which checks
for specific cases where a given PC offset does not have a stack map entry.

Original commit message:

Lifting the PC offset in a2bb730 was a small, lightweight change that
gave us big gains, at least on 32-bit architectures. Here, we make
much more invasive changes that will improve the amount of memory used
by the information previously stored in StackMap objects.

Instead of allocating separate objects for StackMaps, we instead compress
all StackMap information for a given Code object into a single object
(CompressedStackMaps, or CSM for short). This replaces the Array used to
store PC offsets (as Smis) and the individual StackMap objects.

While we lose all canonicalization for individual StackMap entries, the
drop in space required to store stack map information more than offsets that.

-----

The impact on AOT snapshot size when compiling the Flutter Gallery
in release mode:

   armv7: Total size -2.58% (Isolate RO: +14.46%, Isolate snapshot: -22.93%)
   armv8: Total size -1.85% (Isolate RO: +15.69%, Isolate snapshot: -22.97%)

The impact on in-memory, not on-disk, size for the Flutter Gallery as seen
in the Observatory while running a profile (not release) build:

   armv7: Drops from 7.1 MB to 6.2MB (-0.9 MB)
   armv8: Drops from 13.5MB to 11.7MB (-1.8 MB)

-----

Bug: https://github.com/dart-lang/sdk/issues/35274, https://github.com/dart-lang/sdk/issues/38873
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-mac-debug-simdbc64-try
Change-Id: I111b129b0ed64f03184370bceb7cda69d5d4b3c9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/121700
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-10-16 08:25:53 +00:00
Alexander Markov 017a7a6221 Revert "[vm/compiler] Further compress the information previously in StackMaps."
This reverts commit d77f4913a1.

Reason for revert: large number of flaky crashes on flakiness dashboard (https://github.com/dart-lang/sdk/issues/38873); crashes on vm-kernel-mac-debug-simdbc64 bot.

Original change's description:
> [vm/compiler] Further compress the information previously in StackMaps.
> 
> Lifting the PC offset in a2bb730 was a small, lightweight change that
> gave us big gains, at least on 32-bit architectures. Here, we make
> much more invasive changes that will improve the amount of memory used
> by the information previously stored in StackMap objects.
> 
> Instead of allocating separate objects for StackMaps, we instead compress
> all StackMap information for a given Code object into a single object
> (CompressedStackMaps, or CSM for short). This replaces the Array used to
> store PC offsets (as Smis) and the individual StackMap objects.
> 
> While we lose all canonicalization for individual StackMap entries, the
> drop in space required to store stack map information more than offsets that.
> 
> -----
> 
> The impact on AOT snapshot size when compiling the Flutter Gallery
> in release mode:
> 
>    armv7: Total size -2.58% (Isolate RO: +14.46%, Isolate snapshot: -22.93%)
>    armv8: Total size -1.85% (Isolate RO: +15.69%, Isolate snapshot: -22.97%)
> 
> The impact on in-memory, not on-disk, size for the Flutter Gallery as seen
> in the Observatory while running a profile (not release) build:
> 
>    armv7: Drops from 7.1 MB to 6.2MB (-0.9 MB)
>    armv8: Drops from 13.5MB to 11.7MB (-1.8 MB)
> 
> -----
> 
> Bug: https://github.com/dart-lang/sdk/issues/35274
> Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try
> Change-Id: Ie3bb898d557215146260a560423f5fa27bdff512
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/119640
> Commit-Queue: Teagan Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>

TBR=kustermann@google.com,rmacnak@google.com,sstrickl@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: https://github.com/dart-lang/sdk/issues/35274
Change-Id: Ib844b4d52e3aa4aca62a896cfe349c680bda7461
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-debug-simarm_x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/121642
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
2019-10-14 20:20:58 +00:00
Teagan Strickland d77f4913a1 [vm/compiler] Further compress the information previously in StackMaps.
Lifting the PC offset in a2bb730 was a small, lightweight change that
gave us big gains, at least on 32-bit architectures. Here, we make
much more invasive changes that will improve the amount of memory used
by the information previously stored in StackMap objects.

Instead of allocating separate objects for StackMaps, we instead compress
all StackMap information for a given Code object into a single object
(CompressedStackMaps, or CSM for short). This replaces the Array used to
store PC offsets (as Smis) and the individual StackMap objects.

While we lose all canonicalization for individual StackMap entries, the
drop in space required to store stack map information more than offsets that.

-----

The impact on AOT snapshot size when compiling the Flutter Gallery
in release mode:

   armv7: Total size -2.58% (Isolate RO: +14.46%, Isolate snapshot: -22.93%)
   armv8: Total size -1.85% (Isolate RO: +15.69%, Isolate snapshot: -22.97%)

The impact on in-memory, not on-disk, size for the Flutter Gallery as seen
in the Observatory while running a profile (not release) build:

   armv7: Drops from 7.1 MB to 6.2MB (-0.9 MB)
   armv8: Drops from 13.5MB to 11.7MB (-1.8 MB)

-----

Bug: https://github.com/dart-lang/sdk/issues/35274
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try
Change-Id: Ie3bb898d557215146260a560423f5fa27bdff512
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/119640
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
2019-10-11 11:28:57 +00:00
Teagan Strickland a2bb7301c5 [vm/compiler] Lift PC offsets out of StackMaps.
Instead of storing the PC offset inside the StackMap object, store it instead
in the `Array` containing `StackMap`s in `Code` objects. That is, the `Array`
provided by `Code::stackmaps()` no longer contains just `StackMap` objects, but
instead contains `Smi`s and `StackMap` objects in alternating fashion.  Each
`Smi` is the PC offset for the `StackMap` object that follows.

This ends up changing very little code outside of `StackMap`,
`Code::GetStackMap`, and `StackMapTableBuilder`, as there are only two types of
`StackMap` users:

* Users that call `Code::GetStackMap` already have the PC offset.
* Users that call Code::stackmaps() can just fetch the PC offset from the
  returned `Array` instead.

On 64-bit architectures, we will use more space to represent the PC offset
as a Smi in the Array than the old uint32_t field. However, the drop in total
number of StackMap objects due to an increased ability to canonicalize
them should offset this. On 32-bit architectures, we can only represent
30 bit PC offsets, not 32 bit PC offsets, but that shouldn't be a problem
in practice except for pathological cases.

_Numbers from building the Flutter gallery in android_release mode_

Since PC offsets are no longer in the `StackMap` objects, this enables
a lot more canonicalization than before. Previously, we generated
49379 `StackMap`s, but now we only generate 16139 `StackMap`s, just under
a third of the original number. This is because there were a lot of
`StackMap`s that differed only in their PC offset, and now they can
be canonicalized into the same `StackMap` object.

When building the Flutter gallery with android_release, the app.so size
drops from 11276896 bytes to 10908256 bytes, a difference of 368640
bytes, or 3.27%.

Using the AOT snapshot profiling support, we see the following drops:

Heap snapshot size drops from 10.7 MB to 10.4 MB.

`Code`              | Before  | After   | Difference
---------------------------------------------------------
Shallow size        | 352363  | 352363  | 0
Retained size       | 9114801 | 8796064 | -318737
Percent of snapshot | 81.2%   | 80.7%   | -0.5%

`(RO)StackMap`      | Before  | After   | Difference
---------------------------------------------------------
Shallow size        | 49381   | 16141   | -33240
Retained size       | 893965  | 286613  | -607352
Percent of snapshot | 7.97%   | 2.63%   | -5.34%

`StackMap`          | Before  | After   | Difference
---------------------------------------------------------
Shallow size        | 844584  | 270472  | -574112
Retained size       | 844584  | 270472  | -574112
Percent of snapshot | 7.53%   | 2.48%   | -5.05%

As we'd expect from the `StackMap` numbers above, we end up using a little
under a third of the space for `StackMap`s. We actually use even less space
(32.0% of the original) than the drop in `StackMap` numbers (32.7%), because
each `RawStackMap` instance is 32 bits smaller due to dropping the `pc_offset_`
field. Note that even though these PC offsets now show up in the
`Code::stackmaps()` `Array`, we can see this is still a net drop in space used
by looking at the retained size of `Code` objects.

Bug: https://github.com/dart-lang/sdk/issues/35274
Change-Id: I0910a43e7a5a7e2e721676209196be1884c5a71c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/119147
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
2019-10-01 09:12:22 +00:00
Samir Jindel bc16959fc7 Reland "[vm/ffi] Dispatch native callbacks through trampolines if we can't ensure callbacks will always be executable."
The original revision is in patchset 1.

Three bugs are fixed:

1. Fix SIMARM_X64 build: no need to generate trampolines for AOT or simulated JIT.
2. Hot-reload: Fix hot-reload: don't invalidate Code for force-optimized functions.
3. Windows: Provide shadow space to runtime routines.

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-mac-debug-simarm_x64-try,vm-kernel-precomp-mac-release-simarm_x64-try,vm-kernel-reload-linux-debug-x64-try,vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-win-debug-ia32-try,vm-kernel-win-debug-x64-try,vm-kernel-win-release-ia32-try,vm-kernel-win-release-x64-try
Change-Id: I326009cfacb51a84e9de4ddf9ff2d6d415460f91
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/113829
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-08-21 13:33:37 +00:00
Ryan Macnak 240f25a940 [vm] Add --disassemble-relative to use PC offsets instead of absolute PCs in --disassemble's output.
Makes it much easier to compare the output when making VM changes.

--disassemble:
        ;; Invocation Count Check
0x7f82b8900320    498b7c2437             movq rdi,[r12+0x37]
0x7f82b8900325    ff8783000000           incl [rdi+0x83]
0x7f82b890032b    81bf8300000030750000   cmpl [rdi+0x83],0x7530
0x7f82b8900335    7c07                   jl 0x00007f82b890033e
0x7f82b8900337    41ffa6b8010000         jmp [thr+0x1b8]

--disassemble --disassemble-relative:
        ;; Invocation Count Check
0x0    498b7c2437             movq rdi,[r12+0x37]
0x5    ff8783000000           incl [rdi+0x83]
0xb    81bf8300000030750000   cmpl [rdi+0x83],0x7530
0x15    7c07                   jl +9
0x17    41ffa6b8010000         jmp [thr+0x1b8]

Change-Id: Ie05c532f830027b928d7d1d57509eb237157a127
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/106600
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Reviewed-by: Aart Bik <ajcbik@google.com>
2019-06-19 22:36:00 +00:00
Ryan Macnak e4c71e830f [vm, compiler] Fix Code checked entry offsets.
Function entry points have been subject to block scheduling since 06f9a9e354. Block scheduling in AOT never reorders the entries.

Bug: https://github.com/dart-lang/sdk/issues/36409
Bug: https://github.com/dart-lang/sdk/issues/36731
Change-Id: Id6725fed4d9bbd381631fa88c5397435a35acc9a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/102463
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2019-05-21 01:19:28 +00:00