Commit Graph

261 Commits

Author SHA1 Message Date
Alexander Aprelev 5b0285866d Revert "Reland "[vm] Recognize int.trailingZeroBitCount/oneBitCount as graph-inlinable""
This reverts commit 415b040d6f.

Reason for revert: breaks riscv https://github.com/dart-lang/sdk/issues/63479

Original change's description:
> Reland "[vm] Recognize int.trailingZeroBitCount/oneBitCount as graph-inlinable"
>
> The previous attempt was reverted because it broke unoptimized JIT
> on ARM 32. This reland force-optimizes the two getters.
>
> Stacks on top of the int.{trailingZeroBitCount,oneBitCount} API CL
> (commit 754239b077). Both getters route through OTHER_RECOGNIZED_LIST
> when a hardware fast path is available; otherwise the newly added
> Dart bodies inline at call sites via vm:prefer-inline. The C++
> natives are removed.
>
> Backend codegen
> ---------------
> ARM64:     NEON CNT + UADDLV (popcount); RBIT + CLZ (ctz).
> ARM:       NEON CNT + VPADDL chain (popcount); RBIT + CLZ on the
>            register pair (ctz).
> x64:       popcntq when TargetCPUFeatures::popcnt_supported();
>            LoadImmediate(64) + rep_bsfq for ctz (decodes as tzcnt
>            on BMI1+, preserves dest on zero otherwise).
> RISC-V 64: cpop / ctz when RV_baseline includes Zbb.
>
> Per-arch availability is encapsulated in
> UnaryInt64OpInstr::IsSupported(Token::Kind).
>
> Apple M-series ARM64, AOT (us/iter, lower is better):
>   cardinality.swar              371
>   cardinality.accelerated       154    (2.4x)
>   forEachSetBit.swar          19031
>   forEachSetBit.accelerated    4988    (3.8x)
>   select.swar                   199
>   select.accelerated             77    (2.6x)
>   complementCardinality.swar    399
>   complementCardinality.accel   152    (2.6x)
>
> Work towards https://github.com/dart-lang/sdk/issues/6486 (popcount
> and ctz intrinsification).
>
> Work towards https://github.com/dart-lang/sdk/issues/1053 (efficient
> BitSet implementation).
>
> Fixes https://github.com/dart-lang/sdk/issues/52673
> Fixes https://github.com/dart-lang/sdk/issues/38346
> Fixes https://github.com/dart-lang/sdk/issues/63436
> Issue https://github.com/dart-lang/sdk/issues/10212
> Issue https://github.com/dart-lang/sdk/issues/5798
> TEST=tests/corelib/int_bit_count_test
>
> Cq-Include-Trybots: luci.dart.try:vm-linux-release-simarm-try,vm-ffi-qemu-linux-release-arm-try,vm-aot-linux-release-simarm_x64-try,vm-aot-linux-debug-simarm_x64-try,dart-sdk-linux-riscv64-try
> Change-Id: Ib812cbaec6e371b9720df7a543411f78e524cac1
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/506060
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Auto-Submit: Modestas Valauskas <valauskasmodestas@gmail.com>
> Reviewed-by: Slava Egorov <vegorov@google.com>
> Commit-Queue: Martin Kustermann <kustermann@google.com>

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2026-05-29 10:29:33 -07:00
Modestas Valauskas 415b040d6f Reland "[vm] Recognize int.trailingZeroBitCount/oneBitCount as graph-inlinable"
The previous attempt was reverted because it broke unoptimized JIT
on ARM 32. This reland force-optimizes the two getters.

Stacks on top of the int.{trailingZeroBitCount,oneBitCount} API CL
(commit 754239b077). Both getters route through OTHER_RECOGNIZED_LIST
when a hardware fast path is available; otherwise the newly added
Dart bodies inline at call sites via vm:prefer-inline. The C++
natives are removed.

Backend codegen
---------------
ARM64:     NEON CNT + UADDLV (popcount); RBIT + CLZ (ctz).
ARM:       NEON CNT + VPADDL chain (popcount); RBIT + CLZ on the
           register pair (ctz).
x64:       popcntq when TargetCPUFeatures::popcnt_supported();
           LoadImmediate(64) + rep_bsfq for ctz (decodes as tzcnt
           on BMI1+, preserves dest on zero otherwise).
RISC-V 64: cpop / ctz when RV_baseline includes Zbb.

Per-arch availability is encapsulated in
UnaryInt64OpInstr::IsSupported(Token::Kind).

Apple M-series ARM64, AOT (us/iter, lower is better):
  cardinality.swar              371
  cardinality.accelerated       154    (2.4x)
  forEachSetBit.swar          19031
  forEachSetBit.accelerated    4988    (3.8x)
  select.swar                   199
  select.accelerated             77    (2.6x)
  complementCardinality.swar    399
  complementCardinality.accel   152    (2.6x)

Work towards https://github.com/dart-lang/sdk/issues/6486 (popcount
and ctz intrinsification).

Work towards https://github.com/dart-lang/sdk/issues/1053 (efficient
BitSet implementation).

Fixes https://github.com/dart-lang/sdk/issues/52673
Fixes https://github.com/dart-lang/sdk/issues/38346
Fixes https://github.com/dart-lang/sdk/issues/63436
Issue https://github.com/dart-lang/sdk/issues/10212
Issue https://github.com/dart-lang/sdk/issues/5798
TEST=tests/corelib/int_bit_count_test

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Change-Id: Ib812cbaec6e371b9720df7a543411f78e524cac1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/506060
Reviewed-by: Martin Kustermann <kustermann@google.com>
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2026-05-29 06:01:17 -07:00
Alexander Aprelev 8765d80177 Revert "[vm] Recognize int.trailingZeroBitCount/oneBitCount as graph-inlinable"
This reverts commit 0bef837817.

Reason for revert: simarm, xarm bot failures https://github.com/dart-lang/sdk/issues/63436

Original change's description:
> [vm] Recognize int.trailingZeroBitCount/oneBitCount as graph-inlinable
>
> Stacks on top of the int.{trailingZeroBitCount,oneBitCount} API CL
> (commit 754239b077). Both getters route through OTHER_RECOGNIZED_LIST
> when a hardware fast path is available; otherwise the newly added
> Dart bodies inline at call sites via vm:prefer-inline. The C++
> natives are removed.
>
> Backend codegen
> ---------------
> ARM64:     NEON CNT + UADDLV (popcount); RBIT + CLZ (ctz).
> ARM:       NEON CNT + VPADDL chain (popcount); RBIT + CLZ on the
>            register pair (ctz).
> x64:       popcntq when TargetCPUFeatures::popcnt_supported();
>            LoadImmediate(64) + rep_bsfq for ctz (decodes as tzcnt
>            on BMI1+, preserves dest on zero otherwise).
> RISC-V 64: cpop / ctz when RV_baseline includes Zbb.
>
> Per-arch availability is encapsulated in
> UnaryInt64OpInstr::IsSupported(Token::Kind).
>
> Apple M-series ARM64, AOT (us/iter, lower is better):
>   cardinality.swar              371
>   cardinality.accelerated       154    (2.4x)
>   forEachSetBit.swar          19031
>   forEachSetBit.accelerated    4988    (3.8x)
>   select.swar                   199
>   select.accelerated             77    (2.6x)
>   complementCardinality.swar    399
>   complementCardinality.accel   152    (2.6x)
>
> Work towards https://github.com/dart-lang/sdk/issues/6486 (popcount
> and ctz intrinsification).
>
> Work towards https://github.com/dart-lang/sdk/issues/1053 (efficient
> BitSet implementation).
>
> Fixes https://github.com/dart-lang/sdk/issues/52673
> Fixes https://github.com/dart-lang/sdk/issues/38346
> Issue https://github.com/dart-lang/sdk/issues/10212
> Issue https://github.com/dart-lang/sdk/issues/5798
> TEST=tests/corelib/int_bit_count_test
>
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> Change-Id: I9c2c4225fd63d54e190398a0fb6649366317dd17
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/504221
> Commit-Queue: Slava Egorov <vegorov@google.com>
> Reviewed-by: Slava Egorov <vegorov@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Auto-Submit: Modestas Valauskas <valauskasmodestas@gmail.com>

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2026-05-22 14:22:30 -07:00
Modestas Valauskas 0bef837817 [vm] Recognize int.trailingZeroBitCount/oneBitCount as graph-inlinable
Stacks on top of the int.{trailingZeroBitCount,oneBitCount} API CL
(commit 754239b077). Both getters route through OTHER_RECOGNIZED_LIST
when a hardware fast path is available; otherwise the newly added
Dart bodies inline at call sites via vm:prefer-inline. The C++
natives are removed.

Backend codegen
---------------
ARM64:     NEON CNT + UADDLV (popcount); RBIT + CLZ (ctz).
ARM:       NEON CNT + VPADDL chain (popcount); RBIT + CLZ on the
           register pair (ctz).
x64:       popcntq when TargetCPUFeatures::popcnt_supported();
           LoadImmediate(64) + rep_bsfq for ctz (decodes as tzcnt
           on BMI1+, preserves dest on zero otherwise).
RISC-V 64: cpop / ctz when RV_baseline includes Zbb.

Per-arch availability is encapsulated in
UnaryInt64OpInstr::IsSupported(Token::Kind).

Apple M-series ARM64, AOT (us/iter, lower is better):
  cardinality.swar              371
  cardinality.accelerated       154    (2.4x)
  forEachSetBit.swar          19031
  forEachSetBit.accelerated    4988    (3.8x)
  select.swar                   199
  select.accelerated             77    (2.6x)
  complementCardinality.swar    399
  complementCardinality.accel   152    (2.6x)

Work towards https://github.com/dart-lang/sdk/issues/6486 (popcount
and ctz intrinsification).

Work towards https://github.com/dart-lang/sdk/issues/1053 (efficient
BitSet implementation).

Fixes https://github.com/dart-lang/sdk/issues/52673
Fixes https://github.com/dart-lang/sdk/issues/38346
Issue https://github.com/dart-lang/sdk/issues/10212
Issue https://github.com/dart-lang/sdk/issues/5798
TEST=tests/corelib/int_bit_count_test

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Change-Id: I9c2c4225fd63d54e190398a0fb6649366317dd17
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2026-05-22 05:58:10 -07:00
Alexander Markov 51d1c8923a Reland "[vm,dart2bytecode,modular_aot] Variable-length closure objects"
This is a reland of commit 88496ba1c3

Fixes on top of the original change:

* Closure layout is changed to avoid gap between fixed fields and
  variable-length elements on compressed pointers architecture.
  This gap was causing crashes in the GC when scanning closure
  objects.

* pkg/vm_snapshot_analysis/test/instruction_sizes_test is fixed
  on arm64 by decreasing threshold for detecting size changes.

Original change's description:
> [vm,dart2bytecode,modular_aot] Variable-length closure objects
>
> Extend closure objects with variable number of elements to capture.
> This is needed to support capturing multiple independent contexts
> after capturing is computed in the front-end.
>
> The following fixed Closure fields are moved into variable-length
> elements:
>  - delayed type arguments;
>  - instantiator type arguments;
>  - function type arguments;
>  - context.
>
> Number of elements and presence/indices of various type arguments
> are encoded into the new length_and_flags field in the Closure.
>
> Most closure objects don't need any of the type arguments so this
> change will reduce average Closure object size.

TEST=ci
Issue: https://github.com/dart-lang/sdk/issues/61572
Issue: https://github.com/dart-lang/sdk/issues/61635

Change-Id: I8685e632e2d0832766ecdc470f3cf9a6b880de48
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/494243
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
2026-04-10 06:15:22 -07:00
Alexander Markov 0dfaa16dc7 Revert "[vm,dart2bytecode,modular_aot] Variable-length closure objects"
This reverts commit 88496ba1c3.

Reason for revert: crashes on arm64c

Original change's description:
> [vm,dart2bytecode,modular_aot] Variable-length closure objects
>
> Extend closure objects with variable number of elements to capture.
> This is needed to support capturing multiple independent contexts
> after capturing is computed in the front-end.
>
> The following fixed Closure fields are moved into variable-length
> elements:
>  - delayed type arguments;
>  - instantiator type arguments;
>  - function type arguments;
>  - context.
>
> Number of elements and presence/indices of various type arguments
> are encoded into the new length_and_flags field in the Closure.
>
> Most closure objects don't need any of the type arguments so this
> change will reduce average Closure object size.
>
> TEST=ci
> Issue: https://github.com/dart-lang/sdk/issues/61572
> Issue: https://github.com/dart-lang/sdk/issues/61635
>
> Change-Id: I7ca5cec0fd8725c432a01d51781fb14e803997dd
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/489482
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>
> Reviewed-by: Slava Egorov <vegorov@google.com>
> Reviewed-by: Tess Strickland <sstrickl@google.com>

Issue: https://github.com/dart-lang/sdk/issues/61572
Issue: https://github.com/dart-lang/sdk/issues/61635
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Commit-Queue: Alexander Markov <alexmarkov@google.com>
2026-04-09 14:12:09 -07:00
Alexander Markov 88496ba1c3 [vm,dart2bytecode,modular_aot] Variable-length closure objects
Extend closure objects with variable number of elements to capture.
This is needed to support capturing multiple independent contexts
after capturing is computed in the front-end.

The following fixed Closure fields are moved into variable-length
elements:
 - delayed type arguments;
 - instantiator type arguments;
 - function type arguments;
 - context.

Number of elements and presence/indices of various type arguments
are encoded into the new length_and_flags field in the Closure.

Most closure objects don't need any of the type arguments so this
change will reduce average Closure object size.

TEST=ci
Issue: https://github.com/dart-lang/sdk/issues/61572
Issue: https://github.com/dart-lang/sdk/issues/61635

Change-Id: I7ca5cec0fd8725c432a01d51781fb14e803997dd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/489482
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
2026-04-09 12:22:21 -07:00
Ryan Macnak 91cef061c7 [vm, compiler] Create a proper frame in the FFI callback trampoline.
TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/62932
Change-Id: I2b8de8555b3810e4838f4ac36d590a24159291ec
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/490740
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2026-03-31 11:13:00 -07:00
Ryan Macnak 1d91605c25 [vm, compiler] Handle 32-bit constant indices for Load/StoreIndexedInstr on ARM64 and RISC-V.
This extends the set of indices that are not processed by the register allocator to match X64. This avoids slowness in the register allocator for large list literals. For some cases, it also reduces code size.

TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/62411
Change-Id: Iab71a6dea2f2f75b06c51e4b23626bc991e1a20f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/475720
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2026-01-26 14:37:58 -08:00
Ryan Macnak 6d4cfab927 [vm, compiler] Combine cset+sub into csetm for ARM64 IfThenElse.
TEST=ci
Change-Id: I64f70325ceca589ee93663f651a784c9c833ce36
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/464763
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2025-12-01 11:15:43 -08:00
Ryan Macnak 8c73b534f5 [vm] Use dmb ishst instead of dmb ish for store-store fence.
TEST=ci
Change-Id: Id7fb33bb4d9626ad420fd5aac2df86b47bd5c7bf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/459662
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
2025-11-05 13:29:00 -08:00
Ryan Macnak 78d280a2df [vm] Symbolize JIT Dart frames for TSAN.
TEST=tsan
Bug: https://github.com/dart-lang/sdk/issues/61352
Change-Id: I0e64e563b19bbd7b67e6f275dbc373db08b9d2c7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/449980
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2025-09-24 13:14:32 -07:00
Ryan Macnak e01d4b3cc6 [vm, compiler] Get the full Dart stack in TSAN reports.
Call __tsan_func_entry/__tsan_func_exit in functions that use __tsan_read/__tsan_write or call other functions. Call __tsan_func_exit once per frame when unwinding for exceptions. Do so only in AOT, since TSAN won't be able to symbolize JIT functions anyway.

TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/61352
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Change-Id: Ie52c978c25664d78b834e9b72ecf7eb2a12cc2ba
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/444181
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2025-08-26 11:50:13 -07:00
Ryan Macnak e6053248c3 [vm, compiler] Add TSAN instrumentation to Dart field access.
Allows TSAN to detect data races involving Dart fields.

TEST=tsan
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2025-08-06 09:18:43 -07:00
Ryan Macnak dc97aa7fb9 [vm, compiler] Update TSAN instrumentation.
TEST=tsan
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Change-Id: I0c49b501c53f9a5117bb14800e342e6fe9b4eba6
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2025-08-04 15:29:04 -07:00
Ryan Macnak bc17496b00 [vm] Fix Google3 ClangTidy warnings.
TEST=presubmit
Change-Id: Ifa4e77cc4548729526a90683ee163c68517e87ef
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/433001
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2025-06-04 15:14:15 -07:00
Vyacheslav Egorov 8085a97a63 [vm] Fix JumpToFrame execution state transition
Instead of handling FFI related execution state and safepoint
in assembly handle it in runtime code.

The transition needs to be done before JumpToFrame unwinds
stack because unwinding destroys exit frame and this can't
be done at safepoint as GC might be traversing the stack.

An incorrect order of operation was manifesting as crashes in
GC when one isolate in a group was encountering a lot of
exceptions thrown from an FFI call and another isolate is
triggering GCs.

To catch this in the future added a bit of validation to
ExitSafepoint runtime call which triggers when --use-slow-path
is enabled. Though after refactoring this code does not
trigger this code path anymore because it was completely
removed - but it is better than nothing.

This CL also removes a lot of unnecessary complexity which
was associated with handling this transition in the stub
itself.

TEST=ffi/vmspecific_handle_test

Bug: b/408377905
Cq-Include-Trybots: dart/try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-asan-linux-release-x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-msan-linux-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-tsan-linux-release-x64-try,vm-aot-ubsan-linux-release-x64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-arm64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-mac-debug-simarm64_arm64-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-fuchsia-release-x64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-arm64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-tsan-linux-release-arm64-try,vm-tsan-linux-release-x64-try,vm-ubsan-linux-release-arm64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-x64-try,vm-win-debug-x64c-try,vm-win-release-ia32-try
Change-Id: Ia073cb6bb9e1b5a0ea8514c7e048cee6019b84d6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/420324
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2025-04-07 05:22:56 -07:00
Ryan Macnak 4cf27cc968 [vm, compiler] Fix assert assembling add/subs with extended register.
This is not symmetric with add/sub, accepting ZR instead of CSP.

TEST=vm/cc/Assembler_CmpExtReg, dartfuzz
Bug: https://github.com/dart-lang/sdk/issues/60092
Change-Id: Icc24f7883a113eac504fd8fc29c0d6f781cb7657
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/408901
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2025-02-10 15:16:50 -08:00
Alexander Markov f2d70cec04 [vm,arm64] Fix AddImmediate in case of CSP
Use extended register variant of add instruction when Rd or Rn
register is CSP (SP). Also fix assertion which was incorrectly
testing that Rd cannot be CSP if extended register operand is used
(actually it cannot be ZR).

TEST=vm/cc/Assembler_Drop
Fixes https://github.com/dart-lang/sdk/issues/46433

Change-Id: I542dd7bc0661b3195fa466e43cd65998c1c4ac81
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/408141
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
2025-02-05 12:32:39 -08:00
Daco Harkes 5984cc8c24 [vm] Verify transitions in generated code
The transitions in C++ have asserts which run in debug mode to validate
that the transitions are happening in the right order.

The transitions in the generated code had no equivalent. This CL
introduces the equivalent for the generated code.

The transitions to generated code are misnamed currently. They come
from either VM or Native, not only Native. For example the FFI
callbacks and call return sequence can already transition from native
into the VM when entering the safepoint.

These checks don't catch the invalid FFI callbacks.
Bug: https://github.com/dart-lang/sdk/issues/60021
These are caught when looking up the FFI metadata:
https://dart-review.googlesource.com/c/sdk/+/407023

This CL omits to implement the check in ia32, since ia32 is scheduled
for removal.

The check is only enabled in debug mode. The asserts for the C++ are
also only run in debug mode. And enabling this check in release for
AOT regresses the parent CL benchmark by ~30% on Mac Arm64.

TEST=test/ffi

Change-Id: Ieaf1e43533baae294af37b2e171b68bd314fdbe0
Cq-Include-Trybots: dart/try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-asan-linux-release-x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-msan-linux-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-tsan-linux-release-x64-try,vm-aot-ubsan-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-arm64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-fuchsia-release-arm64-try,vm-fuchsia-release-x64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-arm64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-tsan-linux-release-arm64-try,vm-tsan-linux-release-x64-try,vm-ubsan-linux-release-arm64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-arm64-try,vm-win-debug-x64-try,vm-win-debug-x64c-try,vm-win-release-ia32-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/407021
Reviewed-by: Liam Appelbe <liama@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
2025-02-04 03:36:29 -08:00
Ryan Macnak 949eb447a4 [vm, gc] Add write-write fence after initializing object headers, or defer marking new-space objects in an active TLAB.
On architectures with a weak memory model, there is the possibility that the concurrent marker can see the publishing store of a new object before it sees the initializing store of that object's header. On an M1, the barrier to prevent reordering these stores is fairly cheap, so we emit this barrier on Mac/iOS ARM64. Otherwise, this barrier is very expensive (or at least expensive for some hardware within the ABI), so instead we avoid the race by deferring marking of objects inside an active TLAB.

Disable TSAN instrumentation on the marker setting the mark bit, as TSAN does not understand fences.

TEST=ooo arm64 machines
Bug: https://github.com/dart-lang/sdk/issues/56845
Change-Id: I0676661a7cf941fdc6b451e516d890c26826bb3b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/389265
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
2024-10-28 22:41:39 +00:00
Ryan Macnak 889e5795bb [vm, compiler] Use immediate forms for BinaryUint32Op.
dart2js.aot.arm64  28757440 -> 28691320 (-66k)
dart2js.aot.x64    28311232 -> 28310536 (-1k)
dart2js.aot.rv64   27971912 -> 27955200 (-16k)
dart2js.aot.arm32  27793504 -> 27775936 (-17k)

TEST=vm/dart/uint32_op_imm_test
Change-Id: I25e486ea1ab3b20369c0c5a5fafae5d1ea53b1c7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/388120
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2024-10-09 16:47:48 +00:00
Tess Strickland b23584eaa0 [vm/compiler] Add reg, reg, imm forms for lsl/asr/and assembler macros.
For non-x86 architectures, these forms directly translate to a
single instruction when possible. On x86 architectures,
XImmediate(dst, src, imm) where X is in {Lsl, ArithmeticShiftRight, And}
can be translated to:

  MoveRegister(dst, src);
  XImmediate(dst, imm);

in the general case since MoveRegister(dst, src) is a no-op if dst and
src are the same.

Also add versions of these assembler macros that take an OperandSize
and handle 32-bit OperandSizes appropriately on 64-bit architectures.

Ensure the implementation for LslImmediate and
ArithmeticShiftRightImmediate emits no instructions if shift == 0,
dst == src, and OperandSizeInBits(sz) == kBitsPerWord on all
architectures.

-----

Other changes:

Fix ConstantExpression::EmitMoveToLocation on ARM64 to match
other architectures, which allow any word-sized or less unboxed
integer representation.

Fill out ExtendValue on RISCV for previously unimplemented
OperandSizes, using the Zba and Zbb extensions when possible.

-----

TEST=vm/cc/Assembler_AndImmediate vm/cc/Assembler_LslImmediate
     vm/cc/Assembler_ArithmeticShiftRightImmediate

Separated out of https://dart-review.googlesource.com/c/sdk/+/378706
for easier debugging/reviewing.

Change-Id: I721f1334784f7011a958ea8af29f0e56c620726c
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-release-simarm_x64-try,vm-aot-linux-debug-x64-try,vm-aot-mac-release-arm64-try,vm-aot-mac-product-arm64-try,vm-aot-linux-product-x64-try,vm-aot-dwarf-linux-product-x64-try,vm-aot-linux-debug-simarm_x64-try,vm-linux-debug-x64-try,vm-mac-debug-arm64-try,vm-mac-release-arm64-try,vm-linux-debug-ia32-try,vm-aot-android-release-arm64c-try,vm-ffi-android-debug-arm64c-try,vm-aot-linux-debug-x64c-try,vm-linux-debug-x64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/386180
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
2024-10-04 10:07:51 +00:00
Alexander Aprelev 4138277ee6 [vm/shared] Introduce 'vm:shared' pragma.
Decorating a field with 'vm:shared' pragma makes values in this field accessible to all isolates in an isolate group.

Introduce `channel` to the `Version` class so that the pragma can only be enabled on main and dev channels.

TEST=shared_test, shared_fail_without_flag_test
BUG=https://github.com/dart-lang/sdk/issues/55991

Change-Id: I843c9f0d2ffc9f2ced7ddc4006bb6f9ca4e2ddf4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/370064
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
2024-06-14 23:24:19 +00:00
Tess Strickland 324ba0c11f [vm/compiler] Extend Assembler::AddScaled to take a base register.
Add an additional base argument to Assembler::AddScaled so it now
computes:
  dest <- base + (index << scale) + offset

If base is kNoRegister (or ZR when available), then it emits
instructions optimized for computing:
  dest <- (index << scale) + offset
(i.e., its previous implementation)

Add AddScaled to AssemblerBase to ensure the same interface across all
architectures.

Rework the backend of CalculateElementAddress to use AddScaled
appropriately, which unifies it across architectures.

TEST=ci (refactoring)

Cq-Include-Trybots: luci.dart.try:vm-aot-linux-debug-simarm_x64-try,vm-aot-linux-debug-simriscv64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-linux-debug-simriscv64-try,vm-mac-debug-arm64-try,vm-aot-mac-release-arm64-try
Change-Id: I33c8f99604b68360f10b79050bd66ceb9d65ac9b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/370504
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2024-06-11 08:33:29 +00:00
Ryan Macnak 16f3ad9078 [vm, compiler] Assert against unpredictable forms of load/store exclusive on ARM.
Make ARM64 disassembly closer to the standard form.

TEST=ci
Change-Id: I459093abe049835c6597b80c8020566054a12b48
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/368824
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2024-05-30 20:09:29 +00:00
Ryan Macnak 1a9acb9171 [vm, ffi] Make callbacks profiler-safe.
Delay changing Thread::vm_tag on callback entry and restore the tag early on callback return so that the profiler doesn't see the "running Dart" tag unless it can also see the fake return address marking the entry frame.

TEST=ffi/async_void_function_callbacks, ffi/function_callbacks_subtype, ffi/function_callbacks, ffi/isolate_local_function_callbacks
Bug: https://github.com/dart-lang/sdk/issues/52814
Change-Id: I40d80ec7c44063d078db0e211565e2d127c6b81e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367460
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2024-05-28 21:16:41 +00:00
Ryan Macnak 8c1de038e0 [vm, compiler] Allow targeting TSAN or MSAN by passing a flag to gen_snapshot.
Add check that the snapshot and runtime agree on whether to use MSAN. We already have this check for TSAN.

TEST=vm/dart/sanitizer_compatibility_test
Bug: https://github.com/dart-lang/sdk/issues/55637
Bug: https://github.com/dart-lang/sdk/issues/55638
Change-Id: I320e6f55cd59209ce6e58a82ac205a87c8a60a84
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/365487
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Ivan Inozemtsev <iinozemtsev@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
2024-05-08 17:03:59 +00:00
Vyacheslav Egorov 2a2781edff [vm] Add vm:align-loops pragma
This pragma forces compiler to align loop headers within the
function by architecture specific boundary: 32 bytes on X64
and ARM64 (with the exception of Apple Silicon, which explicitly
discourages aligning branch targets in the optimization manual).

Current implementation is rather naive and does not do any
attempt to decide whether aligning is actually profitable
based on loop body itself.

I have found this pragma to be helpful both to stabilize
benchmark results and achieve better performance
for tight loops on Intel hardware.

Issue https://github.com/dart-lang/sdk/issues/55522

TEST=vm/dart/align_loops_test

Cq-Include-Trybots: luci.dart.try:vm-aot-linux-product-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-linux-debug-x64-try,vm-aot-linux-release-arm64-try,vm-aot-linux-release-simarm_x64-try,vm-aot-linux-release-x64-try,vm-aot-mac-product-arm64-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-release-x64-try,vm-aot-win-debug-arm64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-aot-win-product-x64-try,vm-aot-win-release-arm64-try,vm-aot-linux-debug-simarm_x64-try,vm-aot-linux-debug-simriscv64-try,vm-aot-dwarf-linux-product-x64-try,vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try
Change-Id: Ic22fb90d85e7fdebeeaa3908a43328c59436ab58
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/364121
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
2024-04-24 08:52:18 +00:00
Daco Harkes f98a2138b7 [vm] Run clang-format on code base
When uploading CLs, the presubmit checks verify that the lines in the
diff are formatted correctly according to `git cl format runtime`.

However, when `buildtools/<os>-<arch>/clang/bin/clang-format` is
updated, it does not force reformatting of files that would be
reformatted.

This leads to two issues:
* Inconsistent style within the code base and within a single file.
* Spurious reformatting in CLs when (1) clang-format is used on the
  whole file, or (2) the diff lines overlap.

`clang-format` doesn't change that frequently, so in general this is
not a large issue, but I've seen a bit too many "spurious formatting,
please revert" comments on CLs recently.

This CL formats the runtime to be in line with the current pinned
`clang-format`:

```
$ find runtime/ -iname *.h -o -iname *.cc | xargs buildtools/mac-arm64/clang/bin/clang-format -i
```

`git cl format` (which only formats changed lines, and does so with
`clang-format`) seems to not agree with itself, or clang-format, or
cpplint in a handful of places. This CL adds `// clang-format off`
for these. (See previous patchsets for the specific instances.)

TEST=A variety of bots including GCC, MacOS and Windows.

Change-Id: I470892e898971899fda14bb3b8f2c8efefd67686
Cq-Include-Trybots: luci.dart.try:vm-gcc-linux-try,vm-ffi-qemu-linux-release-riscv64-try,vm-ffi-qemu-linux-release-arm-try,vm-aot-win-debug-x64-try,vm-win-debug-x64c-try,vm-mac-debug-x64-try,vm-mac-debug-arm64-try,vm-aot-linux-debug-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/362780
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
2024-04-17 19:14:41 +00:00
Tess Strickland 671f271f58 [vm/compiler] More consolidation of Store assembler methods.
Add OperandSize arguments to the non-compressed Store methods so that
the compressed Store methods can be implemented as calls to the
corresponding non-compressed method using kObjectBytes. This makes it
so that all compressed Store methods are now non-virtual.

Add a scratch register argument to all Store methods that involve a
write barrier that defaults to TMP. Originally only the IA32
implementation took a scratch register, with the others using TMP or
TMP2 internally.

Since all architectures can represent a register/offset pair as an
Address without losing information, make all the offset-based load
and store methods have an implementation that creates an Address or
FieldAddress and calls the corresponding address-based store method.
This makes all the offset-based load and store methods non-virtual.

After this, most of the Store methods are non-virtual, with
only the base methods used to implement them as virtual:

* Store
* StoreRelease
* StoreObjectIntoObjectNoBarrier
* StoreBarrier
* ArrayStoreBarrier
* VerifyStoreNeedsNoWriteBarrier (for DEBUG use only)

The Load methods can't be consolidated quite so much, as the
base methods for handling non-Smi compressed pointers must be defined
per-architecture, as each compressed pointer architecture handles
adding the upper bits for the heap separately.

Have LoadFieldInstr::EmitNativeCode use Assembler::LoadToSlot when the
result location is a single integer register and
StoreFieldInstr::EmitNativeCode use Assembler::StoreToSlot and
Assembler::StoreToSlotNoBarrier when the value location is a single
integer register to avoid code duplication between those methods.

Handle both compressed and uncompressed Smi fields in LoadFromSlot.

TEST=ci (refactoring)

Cq-Include-Trybots: luci.dart.try:vm-aot-android-release-arm64c-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-x64-try,vm-win-release-ia32-try
Change-Id: I60cc03776af220ed87918664bb4b9abafff2788a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/360641
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2024-04-04 10:41:15 +00:00
Tess Strickland 9fc280a7f6 [vm/compiler] Add all Compressed Assembler methods to AssemblerBase.
Remove CompareWithCompressedFieldFromOffset, which has no uses.

Rename the LoadFromOffset and StoreFromOffset methods that took
Addresses to Load and Store, respectively. This makes the names
of the Assembler methods more uniform:

  * Takes an address: Load, Store, LoadField, LoadCompressedField,
    StoreIntoObject, StoreCompressedIntoObject, LoadSmi,
    LoadCompressedSmi, etc.
  * Takes a base register and an offset: LoadFromOffset, StoreToOffset,
    LoadFieldFromOffset, LoadCompressedFieldFromOffset,
    StoreIntoObjectOffset, StoreCompressedIntoObjectOffset,
    LoadSmiFromOffset, LoadCompressedSmiFromOffset, etc.

Create AssemblerBase methods for loading and storing compressed
pointers that weren't already there, as well as the corresponding
methods for loading and storing uncompressed values.

Make non-virtual methods that load and store uncompressed fields
that call the corresponding method for loading from and storing to
memory regions, adjusting the address or offset accordingly. This
avoids needing per-architecture overrides for these.

Make non-virtual methods that load compressed fields, calling the
corresponding method for loading a compressed value from a memory
region. (Since compressed pointers are only stored in Dart objects,
and stores into a Dart object may require a barrier, there is no
method for storing a compressed value into an arbitrary memory region.)

Create pure virtual methods for loading from or storing to an Address
or any method that does not have both an Address-taking and a
base register and offset pair-taking version (e.g., LoadAcquire).

Create methods for loading from or storing to a base register
and an offset. The base implementation takes the base register and
offset and creates an Address from it, then calls the Address-taking
equivalent. These methods are non-virtual when the implementation is
the same on all architectures and virtual to allow overriding when
necessary.

Make a non-virtual method for loading uncompressed Smis, since all
architectures have the same code for this, including the DEBUG check.

If compressed pointers are not being used, all the methods for
compressed pointers are non-virtual methods that call the
corresponding method for uncompressed values.

If compressed pointers are being used:

* Install pure virtual methods for loading compressed values from
  and storing compressed values to an Address or any method that does
  not have both an Address-taking and a base register and offset
  pair-taking version (e.g., LoadAcquireCompressed).

* Install virtual methods for loading compressed values from and
  storing compressed values to a base register and offset. Like the
  uncompressed implementation, the base implementation of these
  create an Address and call the Address-taking equivalent, and these
  implementations are overridden on ARM64.

* Install a non-virtual method for loading compressed Smis, since the
  only difference is that it loads a zero-extended 32-bit value, which
  AssemblerBase can do.

TEST=ci (refactoring only)

Change-Id: I934791d26a6e2cdaa6ac5f188b0fd89dbdc491d1
Cq-Include-Trybots: luci.dart.try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-arm64-try,vm-win-debug-x64-try,vm-win-release-ia32-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/359861
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2024-04-02 14:54:13 +00:00
Tess Strickland 0d3ade255b [vm/compiler] Limit exposure of untagged pointers to managed memory.
After https://dart-review.googlesource.com/c/sdk/+/330600, there were
more chances for the optimizing compiler to introduce or move
GC-triggering instructions like allocations or boxings between the
retrieval of an untagged pointer to GC-moveable memory and its use.

To limit the chance of this happening, this CL removes the explicit
loading of the untagged payload address when building the initial
flow graph in most cases when the array is not known to be an external
array (an external string, an external typed data object, or an FFI
Pointer).

The remaining case is during view allocation, which extracts the
payload address of the base typed data object underlying the view
(which may be GC-movable) to calculate the payload address that should
be stored in the data field of the view object. See
https://github.com/dart-lang/sdk/issues/54884.

During canonicalization of LoadIndexed, StoreIndexed, and MemoryCopy
instructions, if the cid of an array input is an external array
(external string, external typed data object, or Pointer), then a
LoadField instruction that extracts the untagged payload address
is inserted before the instruction and the corresponding input is
rebound to that LoadField instruction.

Once all compiler passes that involve code motion have been performed,
a new pass looks for LoadIndexed, StoreIndexed, or MemoryCopy where
the cid stored in the instruction for the array is a typed data cid.
In these cases, if the array is not an internal typed data object,
then the payload address is extracted. Waiting until this point ensures
that no GC-triggering instructions are inserted between the extraction
of the payload address and the use. (Internal typed data objects are
left as-is because the payload address is inside the object itself
and doesn't require indirection through the data field of the object).

This CL also replaces code conditional on the array cid with code
that is instead conditional on the array element representation in
cases where it makes sense to do so, since this is a less brittle
check than checking the array cid (e.g., checking for kUnboxedInt8
to load, store, or copy an signed byte from an array instead of
listing all possible array cids that store signed bytes).

This CL also fixes an issue with the ARM64 assembler where calling
LoadFromOffset with an Address that has a non-Offset type would
silently generate bad code instead of triggering the ASSERT in
PrepareLargeOffset.

TEST=vm/dart/typed_list_index_checkbound_il_test

Issue: https://github.com/dart-lang/sdk/issues/54710
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Change-Id: I25b5f314943e9254d3d28986d720a5d47f12feeb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/352363
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2024-03-22 10:12:39 +00:00
Tess Strickland ecf5abcbd3 [vm/compiler] Better handle small array element representations.
Moves RepresentationOfArrayElement out of LoadIndexed and StoreIndexed
into RepresentationUtils. Adjusts RepresentationOfArrayElement
to work for all concrete typed data classes. Changes
RepresentationOfArrayElement to return the precise representation of
the array element, which requires adding two new representations,
kUnboxedInt8 and kUnboxedInt16.

Remove Address::OperandSizeFor and its only (ignored) use in the
RISCV assembler and change Address::OperandSizeFor in the ARM and
ARM64 assemblers to use RepresentationUtils::OperandSize and RepresentationUtils::RepresentationOfArrayElement appropriately.

Add Boxing::NativeRepresentation, which converts representations for
unboxed integers smaller than 4 bytes to kUnboxedIntPtr and otherwise
returns the original representation. This mimics the current semantics
for LoadIndexed and StoreIndexed where returned values represented by
unboxed integer values smaller than 4 bytes are zero or sign extended
to word size appropriately, and received values represented by unboxed
integer values smaller than 4 bytes are appropriately truncated from a
word sized signed integer.

Create LoadIndexedInstr::ReturnRepresentation and
StoreIndexedInstr::ValueRepresentation, which use
Boxing::NativeRepresentation to convert the precise representation
returned by RepresentationUtils::RepresentationOfArrayElement to
the actual returned/expected representation for those instructions.
Also use Boxing::NativeRepresentation to appropriately adjust
the representations used for SIMD operations returning int8_t.

Add checks that unboxing and integer conversion never get
representations which result in a different representation when
passed to Boxing::NativeRepresentation, as those instructions do
not currently work with unboxed integer representations smaller than
4 bytes. (Adding such support can be done in a future CL.)

Inside the optimizing compiler, use the precise representation of the
array element where appropriate. That is:

* Range analysis
* Type propagation
* Redundancy elimination

This CL also cleans up how Representations are printed to C, making
that part of RepresentationUtils. It also removes the representation
printing and parsing utils from Location since they were only used by
the original IL serializer and deserializer, which has been removed.
It also renames RepresentationUtils::IsUnsigned to IsUnsignedInteger,
to make it clear that it only returns true for unboxed integer
representations.

TEST=standalone/bytedata_test

Fixes: https://github.com/dart-lang/sdk/issues/54622
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Change-Id: I8c0dab911463ee4d0c55cd59ffea9d01e0f0bb7c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/354885
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
2024-03-13 14:14:55 +00:00
Ryan Macnak 7fd8d79e91 [vm, compiler] Assert against using CSP as the source/destination register for ld[x]r/st[x]r.
Fix simulator misinterpreting R31 for ldxr/stxr.

TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/54703
Change-Id: I21d1d60f61928c766c2854024cce36e93f7fb665
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/348041
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2024-01-24 01:06:28 +00:00
Ryan Macnak 58bf203064 [VM] Add support for allocation tracing in AOT
TEST=Manual
Bug: https://github.com/dart-lang/sdk/issues/51234
Change-Id: I4ab75bb85898a41dfb091b38402711170fd3b972
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/271420
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
2024-01-17 13:50:49 +00:00
Tess Strickland 1827fcbf68 [vm/compiler] Fix uses of constant indexes in LoadIndexed/StoreIndexed.
Previously, CanBeImmediateIndex calculated the scaling factor for the
index using Instance::ElementSizeFor. However, the LoadIndexed and
StoreIndexed instructions which use this function have an index_scale_
field that is not necessarily the same as the element size for the
class id. This means the displacement calculated within
CanBeImmediateIndex can differ from the actual displacement calculated
within ElementAddressForIntIndex, causing the bug seen by the fuzzer.

This CL moves the check in CanBeImmediateIndex to a new static
method Assembler::AddressCanHoldConstantIndex. In addition to the
original arguments to CanBeImmediateIndex, the new static method takes
an index_scale argument, so the field value can be passed appropriately.

It also adds an is_external argument on X64 and IA32 to match the other
architectures, since assuming a non-external typed data object could
cause a register to be used in cases where it isn't necessary.

TEST=vm/dart/regress_54486

Fixes: https://github.com/dart-lang/sdk/issues/54486
Change-Id: Ia553fb7da0500113b35f8d9af91a52df55437a3c
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/345002
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2024-01-08 15:46:01 +00:00
Ryan Macnak 739d987c91 [vm, compiler] Add MSAN support for ARM64.
TEST=local
Bug: https://github.com/dart-lang/sdk/issues/52399
Change-Id: I6af1954c70208534e87b6b87dd5cf62aaf595bd3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/329582
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
2023-11-28 23:52:49 +00:00
Vyacheslav Egorov dcac60b672 [vm/aot] Fix BoxInt64 in deferred units
When generating code for deferred units compiler
can't emit PC relative call to the shared Mint allocation
stub. This causes compiler to emit an indirect call
through a Code object. Such calls clobber CODE_REG
which is actually an allocatable register.

Fix this by using non-allocatable register instead of
CODE_REG when generating indirect calls through
Code object in AOT mode. Callees don't expect
anything useful in CODE_REG anyway because AOT
calling convetion does not use it.

TEST=vm/cc/{BranchLinkPreservesRegisters,JumpAndLinkPreservesRegisters,CallCodePreservesRegisters}

Bug: b/242559057
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Change-Id: Ib1fdc1c104d0269d41bb1ab9cbe292ad28c7cd49
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/338127
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
2023-11-28 13:15:56 +00:00
Daco Harkes 0cd55a18c1 [vm] Introduce cachable idempotent calls
Adds a `CachableIdempotentCallInstr` that can be invoked via
`@pragma('vm:cachable-idempotent')` if the call-sites is force
optimized.

The object pool is not visited by the scavenger. So, we store the
results as unboxed integers. Consequently, only dart functions that
return integers can be cached.

Cachable idempotent calls should never be inlined. After the first
call the function not be called again.

The call itself is on a slow path to avoid register spilling on the
fast path.

TEST=vm/cc/IRTest_CachableIdempotentCall
TEST=runtime/tests/vm/dart/cachable_idempotent_test.dart

Bug: https://github.com/dart-lang/sdk/issues/51618
Change-Id: I612e896f27add76f57796c060157e14cc687a0fd
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/301601
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2023-10-27 07:55:47 +00:00
Ryan Macnak 378b9fcda4 [vm] More fixes for ARM64 MSVC.
TEST=--no-clang
Change-Id: I9e449ce5270adcf6254602c59a625ca9af3f1082
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/331219
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
2023-10-24 15:04:36 +00:00
Daco Harkes 243cf59776 [vm] Object pool SnapshotBehavior for bootstrapping native functions
`NativeCallInstr::EmitNativeCode` `link_lazily` code path uses the
new snapshotting behavior, and the non-`link_lazily` checks that it's
never snapshotted.

The snapshot behavior argument is threaded from the the EmitNativeCode
to the places where the pool entry is constructed.

Does not yet migrate `kSwitchableCallMissEntryPoint` and
`kMegamorphicCallEntryPoint`.

TEST=CI

Change-Id: I8dd1dc5aa525f888b493856c60ae385087463d02
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/328861
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2023-10-18 13:27:26 +00:00
Daco Harkes 0e9e000264 [vm] Unify LoadInt32FromBoxOrSmi in assemblers
And add unit tests.

TEST=vm/cc/Assembler_LoadInt32

Change-Id: Ib697a0beae97968a0d1ae50c54b5769d9c2a23de
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/328521
Reviewed-by: Tess Strickland <sstrickl@google.com>
2023-09-30 08:12:16 +00:00
Ryan Macnak ef1c3098a1 [vm, compiler] Implement unboxed SIMD for RISC-V via lowering.
This relands commit 460bd7a03a.

TEST=ci
Change-Id: I0b5e91a3b8b6e8afa3f889afa21afed7c1a7e62c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/327821
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2023-09-27 16:23:38 +00:00
Daco Harkes b64212b111 [vm] Make UnboxInstr logic reusable in assembler
Only unifies wordsize unboxed loads, and skips ia32. Leaves the other
UnboxInstr machine code untouched.

TEST=vm/cc/Assembler_LoadWordFromBoxOrSmi

Change-Id: Ib24f503cef257001838928371c2d442465100b11
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2023-09-27 13:05:49 +00:00
Ryan Macnak 139ff289db [vm, compiler] Allocation canaries.
Before each allocation, check the memory hasn't been touched since page initialization. This more reliably detects the issue fixed in a4381f127c.

TEST=ci
Change-Id: I5c0ed0a18a32515eab2ae90110b5a7e7f48779dc
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/325366
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
2023-09-15 17:04:55 +00:00
Martin Kustermann 2287c76724 [vm] Make AOT compiler use TARGET_USES_THREAD_SANITIZER
The VM has two parts related to TSAN: compiler & runtime.

So far both parts used self-detection whether running with TSAN. This
implies that if AOT runtime runs under TSAN that the AOT compiler then
also has to run under TSAN (which is slow).

We separate the two by making the compiler use
`TARGET_USES_THREAD_SANITIZER`. It will be auto-detected by-default
except when `DART_PRECOPMILER` is set. In the precompiler case we
require the build rules to pass in whether the target runs under
TSAN or not.

Issue b/287638965

TEST=ci

Change-Id: Ib333a8a69ed2d7bdca7596014a0d25b103af25b6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/312480
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
2023-07-06 08:44:33 +00:00
Tess Strickland 396796fba9 [vm] Abstract out pieces of SubtypeTestCache stubs across architectures.
Also eliminates the need to store the delayed type arguments on the
stack during the search loop on ARM.

TEST=vm/cc/TTS

Change-Id: Ife01cc8d255724c272bc277eec397486cedc07a7
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2023-06-13 09:53:12 +00:00
Tess Strickland 4b8aa6a634 [vm] Update assembler to access AbstractType::flags_ as Uint32.
In d592882f, the old uint8_t `type_state_` and `nullability_` fields
in subclasses of `AbstractType` were merged into a single uint32_t
`flags_` field in `AbstractType` itself.

Accessing the nullability information was abstracted into two methods:

* `LoadAbstractTypeNullability`
* `CompareAbstractTypeNullabilityWith`

However, the code from these methods were based off the old
`CompareTypeNullabilityWith` and `CompareFunctionTypeNullabilityWith`
methods that used unsigned byte loads to access the old field, and kept
that even though the new field is now a 32-bit unsigned integer. This
works for now, because the nullability portion of the `flags_` field
happens to be the lowest two bits, but might lead to confusion if
someone attempts to write similar code for accessing the other parts of
the `flags_` field without realizing it's larger than 8 bits.

Thus, this CL does the following:

* Unifies the implementation of both methods across architectures.
* Adds a native slot definition for the `AbstractType::flags_` field
  and uses `LoadFromSlot` to load the `flags_` field instead. Other
  places where the `AbstractType::flags_` field is accessed from the
  assembler are also changed to use `LoadFromSlot` appropriately.

TEST=The existing suite of tests are sufficient.

Change-Id: Ie578e4dddce810223ca9e767403136cb40d340f3
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-release-x64-try,vm-aot-linux-release-simarm_x64-try,vm-aot-linux-release-simarm64-try,vm-aot-linux-debug-simarm_x64-try,vm-aot-linux-debug-simriscv64-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-linux-debug-x64c-try,vm-kernel-precomp-linux-release-simarm-try,vm-linux-release-x64-try,vm-linux-release-simarm64-try,vm-linux-release-simarm-try,vm-linux-release-ia32-try,vm-linux-debug-simriscv64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302187
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
2023-05-10 22:40:58 +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