This patch replaces D3D12_BLEND_DEST_ALPHA with D3D12_BLEND_ONE
when the color target formats have no alpha-channel.
Using D3D12_BLEND_ONE is an optimization over
D3D12_BLEND_DEST_ALPHA as it means the GPU hardware doesn't
need to get destination pixel at all. As D3D SPED requires the
default value for missing components in an element format is
"0" for any component except A, which gets "1", using
D3D12_BLEND_DEST_ALPHA takes same effect with
D3D12_BLEND_ONE when the color target formats have no alpha
channel.
In addition, replacing D3D12_BLEND_DEST_ALPHA with
D3D12_BLEND_ONE also serves as a workaround against an Intel
driver issue about alpha blending.
Bug: dawn:1579
Change-Id: If79e4c8007b68dd35e142ba9cf8a4921e611890a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/120120
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
This CL moves the type::Access builtin to the builtin:: tree.
Change-Id: I3276d364f7b597671612a23c8823f0afd1914d81
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/120363
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Dawn provides external semaphore service in static way by compiling
implementation files based on OS type.
A better way is to select external semaphore in runtime.
This CL adds ServiceImplementation interface and implements it for
different semaphore type. Semaphore service delegate work to
implementation in runtime.
This CL also removes "DAWN_USE_SYNC_FD" macro.
Bug=dawn:1593
Change-Id: Idc3f7b644430aad76198ef66dc5ba13e8cfc5a4d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/119321
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Shaobo Yan <shaobo.yan@intel.com>
This was wrong.
DAWN_PLATFORM_IS_X86 is defined for both 32-bit and 64-bit
X86 builds.
Bug: dawn:1254
Change-Id: I308ac10749edcf76643539eb2801d019dd5439f9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/119900
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
This patch adds the support of the optional feature "bgra8unorm-storage"
on D3D12 when the platform allows using DXGI_FORMAT_B8G8R8A8_UNORM as
UAVs.
According to D3D12 documents, enabling the flag
D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS when creating textures requires
"either the texture format must support unordered access capabilities at
the current feature level. Or, when the format is a typeless format, a
format within the same typeless group must support unordered access
capabilities at the current feature level".
Bug: dawn:1641
Test: dawn_end2end_tests
Change-Id: If16271b5da52423e73ad4f7ba258af83dbf66dd2
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/119345
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
This patch implements the optional feature "bgra8unorm-storage" on
Vulkan. As SPIR-V doesn't support 'bgra8' as a valid image format,
we have to create an image view with RGBA8Unorm format on the
BGRA8Unorm texture when we want to use it as a storage texture.
Bug: dawn:1641
Test: dawn_end2end_tests
Change-Id: I4aeea96ae872fe4e6367c535afb6ab896b952453
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118021
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
These textures still have some outstanding issues on both Intel and AMD,
where the wrong subresource can be read from.
Zero-initialization workarounds have been enabled to ensure that even
when the wrong subresource is read, uninitialized data is not read.
Bug: dawn:704, dawn:791, dawn:838
Change-Id: Ib118eff0c5ed5e7812fa70e88ece5317c1af13b0
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116849
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>
Adds a basic adapter blocklist and adds two cases to it.
By default, the blocklist is disabled until Chromium can enable it
explicitly - perhaps based on --enable-unsafe-webgpu or some other
flag. It will be switched to default to true in the future.
about://gpu would disable the blocklist so all the adapters are
visible there, but WebGPU would enable it. Trusted users of Dawn
that are aware of potential bugs may also disable it.
One downside is that about://gpu won't surface directly that an
adapter is on the system, but blocklisted for WebGPU. Something
like that can be added in the future, if necessary.
In the future, this should probably be merged with Chromium's
software_rendering_list.json, but that list doesn't support
multi-adapter systems well (for blocklisting just one adapter),
and it doesn't understand all the information we need for the
current blocklist.
Bug: dawn:1254, dawn:1196, tint:1753
Change-Id: I992bcd10dd5d3f5b23319fc4ec699b06bb1117da
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/119061
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Still a missing condition to enable timestamp period calculation at
device initialization on Metal.
Refactor GPUTimestampCalibrationTests.cpp to check timestamp query
correctness on both D3D12 and Metal backends.
Bug: dawn:1193
Change-Id: I69feeaea0df309e15c008647d76b11899dcdc727
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/119320
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Hao Li <hao.x.li@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
This patch adds the support of the optional feature "bgra8unorm-storage"
and enable it on Metal.
Bug: dawn:1641
Test: dawn_end2end_tests
Change-Id: Id58cefd8735f46b8d1807376ebcfada10df2890e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/111380
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
To avoid uninitialized reads of depth stencil data, where the Metal
driver incorrectly binds/loads the wrong depth stencil subresource,
always keep all depth stencil subresources initialized. This means
that textures are initialized on creation, and StoreOp::Discard is
never used - Store is used instead.
Texture initialized state is still set as-if the Discard occured, so
Dawn will try to zero-initialize the subresource if it is read from.
In many cases, this will work correctly, and the application will
read back 0, as expected. In some cases, Metal will bind the wrong
subresource, and the previous contents will be read. This is wrong,
but at least it is not uninitialized data.
Bug: dawn:838
Change-Id: I3cc87073d52de60283e3b683bbee7809db803018
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/119344
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Shrek Shao <shrekshao@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
This CL refactor the logic adapter creating device toggles set when
creating device and the way device holding its toggles. This CL also
introduce the concept "toggle stage", currently "device stage" only but
in future will add "instance stage" and "adapter stage" for instance and
adapter toggles. No changes on Dawn API.
More details:
1. Introduce `TogglesState` objects that represent the complete toggles
state of a device (and will used for instance and adapter in future).
2. When creating a device, adapter set up a TogglesState object for it
in `AdapterBase::CreateDeviceInternal` and
`Adapter::SetupBackendDeviceToggles`, no other place would change
the device's toggles state. This change simplify the logic.
3. Introduce the `ToggleStage` enum for every toggle and `TogglesState`
object. Currently we only have `Device` toggle stage, but in future
will have `Instance` and `Adapter` for instance and adapter toggles.
Bug: dawn:1495
Change-Id: Ifafac6a6a075b5b9a733159574ae5b6d4f3ebde9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118030
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Zhaoming Jiang <zhaoming.jiang@intel.com>
- Removes remaining usages of the values in Dawn and removes tests.
- Note that the values will be removed from the JSON entirely in
follow up CL after Chromium side changes.
Change-Id: I30ccb3c412cd97047065ad515f6a5ff4de642420
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117593
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Loko Kung <lokokung@google.com>
This patch adds a workaround on Intel Gen9.5 and Gen11 GPUs to always
allocate renderable 2D textures as committed resources instead of
placed resources to mitigate a driver bug about CreatePlacedResource().
Bug: dawn:1628
Change-Id: I38062115d94933bd58e571c812ff6888e9781df6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/100640
Commit-Queue: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
With this CL, GL backend and other backends will use the similar way
to track buffer usage, so the GL MapAsync(Write) will not synchronize
GL commands anymore.
Change-Id: I9f8dfeb58faaed09ed62550371a30a680cd607d5
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118140
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Peng Huang <penghuang@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Add a chained struct for Dawn-specific options for SPIR-V ingestion to
contain this new flag.
Bug: tint:1890
Change-Id: I1332ff20c91f29a84c21550a37f11bc7d9c956ce
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118421
Reviewed-by: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: James Price <jrprice@google.com>
This CL make vulkan adapter checks essential Vulkan extensions and
features in InitializeImpl rather than InitializeSupportedFeaturesImpl.
This change makes InitializeSupportedFeaturesImpl never result in Error
for all backend, and this CL change the return type of
InitializeSupportedFeaturesImpl from MaybeError to void.
Bug: dawn:1495
Change-Id: If59c5aa5281776226c157451ee5119052d33ac24
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118031
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Zhaoming Jiang <zhaoming.jiang@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Change-Id: I4706e517608d436fa646537fec9e930ae47d1c40
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118029
Commit-Queue: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Loko Kung <lokokung@google.com>
Fixes T2T depth copies on Mac Intel where the destination
subresource is a non-zero mip/layer.
Fixed: dawn:1083
Change-Id: If344b46c3fd436d857906850fc0ac5ccb4b93e1d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117592
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
This workaround is needed unless the system is MacOS 13.1+
with architecture at least AMD gcn-4.
Bug: dawn:1389
Change-Id: I3a85be150a0c5ca8b0b74e4b097906f278dd3049
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118023
Reviewed-by: Loko Kung <lokokung@google.com>
Kokoro: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>
Previously we were checking against a list of skipped messages using
both the pMessageIdName and pMessage from a Vulkan debug info callback.
The spec, however, indicates that the pMessageIdName may be NULL.
This change checks to see if that value is NULL before doing any further
checks, and if so always indicates that the message should not be
skipped. (No other code in Dawn references the pMessageIdName.)
See the appropriate page of the Vulkan spec for details:
https://registry.khronos.org/vulkan/specs/1.3-extensions/man/html/VkDebugUtilsMessengerCallbackDataEXT.html
Change-Id: Idd8bf312db31d6cea8e6ce42a47254f182b1070e
Bug: chromium:1411047
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117594
Kokoro: Kai Ninomiya <kainino@chromium.org>
Kokoro: Brandon Jones <bajones@chromium.org>
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
When rotation metadata is added to videos by ffmpeg, it is specified as counter-clockwise. Dawn should follow this format to avoid confusion during integration.
Bug: chromium:1316671
Change-Id: I99ff30bffb1664aafd060d9a5bb1b15845388386
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117912
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Brandon1 Jones <brandon1.jones@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Works around issues on Metal Intel where CopyB2T and WriteTexture
with depth/stencil textures do not work correctly.
Fixes test failures with depth16unorm in the CTS.
Deletes UseTempTextureInStencilTextureToBufferCopy in favor of
the stencil blit. The former supposedly fixes a problem where
the stencil data is not flushed into the real stencil texture
by performing another T2T copy. This only works because the Metal
Intel backend also happens to allocate s8 as d32s8. Copying
the depth aspect as well seems to make the driver remember to
flush the data.
The stencil blit is a better fix for the problem since entirely
avoids getting the driver into a bad state where the stencil data
is not in sync.
Fixed: dawn:1389
Change-Id: If34b1d58996157036c164a5bc329e38b5e53f67a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117910
Reviewed-by: Loko Kung <lokokung@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
- It doens't know which operator == to use when there is using
EnumClassBitmask that looks like (a & b) == 0. Instead use just
the form (a & b).
- It doesn't do automatic capture of constexpr variables in lambdas so
turn a couple constexpr into regular const.
- It (correctly) warns that if constexpr (std::is_constant_evaluated())
is always true, so remove the constexpr keyword.
Bug: None
Change-Id: If7857abd1c30acb0736557844ff13f32a19d54cf
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117888
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Corentin Wallez <cwallez@chromium.org>
This CL deprecates DawnTogglesDeviceDescriptor and replace it with
DawnTogglesDescriptor, which will be also used to provide instance
and adapter toggles with future CLs.
Bug: dawn:1495
Change-Id: I5f5cfdf38dcbcd237727a7f921462597b9301f1f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117174
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Kokoro: Zhaoming Jiang <zhaoming.jiang@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
A bad assert was causing devices that only supported Vulkan 1.0, such as
the Nexus 5X, to crash when querying information about adapter
properties and features. This change removes the need for the ASSERT.
(Note that this does not guarantee WebGPU support on Vulkan 1.0 devices.
For example, the Nexus 5X does not have the fragmentStoresAndAtomics
feature, which is required for WebGPU.)
Bug: dawn:286
Change-Id: I7f884290f29ae7e9607933f6186feac2ce8af540
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117840
Commit-Queue: Brandon Jones <bajones@chromium.org>
Reviewed-by: Loko Kung <lokokung@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
So the next MapAsync() call, doesn't need to record pipeline barrier
command into the pending command buffer, submit it, and wait for it
completion.
Bug: b/265152896
Change-Id: Ied7cbca24a7b1bc81c0a6402179452599aabfe9b
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116920
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Peng Huang <penghuang@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
The fuzzer produced a shader with this format and hit an UNREACHABLE
in Dawn.
Bug: dawn:1641, chromium:1410048
Change-Id: Ia5ba66a18fc718f7e6dd803f4229ecb12b02753e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117531
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
This CL moves the ast/access files into type/access to resolve the type
dependency on ast
Change-Id: Ic0973c5ad162166736abb07cf9bbed7efa91695b
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117605
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Adds a toggle to workaround another issue where Metal fails to set
the depth/stencil attachment correctly for a combined depth stencil
format if just one of the attachments is used. The workaround forces
both attachments to be set, giving the unused one LoadOp::Load and
StoreOp::Store so its contents are preserved.
Bug: dawn:1389
Change-Id: Iacbefcc57b33bf11ca8fcacb03506301646fe59d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117175
Reviewed-by: Loko Kung <lokokung@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
This CL fix FeatureState for some experimental features to prepare for
refactoring adapter creation with adapter toggles. This CL also fix the
related unittests.
Bug: dawn:1495
Change-Id: Ibf043ed74c0bfc79c64986f2f96135d92adf3930
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116841
Reviewed-by: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Auto-Submit: Zhaoming Jiang <zhaoming.jiang@intel.com>
Commit-Queue: Zhaoming Jiang <zhaoming.jiang@intel.com>
Browsers won't be exposing the ability to pass SPIR-V shaders, and the
ability to consume and validate them is adding a non-trivial amount to
the browser binary size on platforms like Android. To avoid that
overhead, this change puts those features behind a flag so that browser
usage can easily omit them.
Bug: dawn:286
Change-Id: Idf70683f2c4ccf479b723c00ba6914e27e4f765f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117241
Commit-Queue: Brandon Jones <bajones@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Add the last usage serial in Buffer, it is used for optimizing
MapAsync(), so the callback of MapAsync() is called when the last usage
serial is done instead of using the current pending serial when
the MapAsync() is called.
Bug: b/265151060
Change-Id: Ibc95d4e41d41896f0a49b0fd1068912b46ea14e1
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116693
Commit-Queue: Peng Huang <penghuang@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
This CL removes StagingBuffer to start to unify implementation
code paths for WriteTexture/Buffer and CopyBufferToTexture/Buffer.
This will help implementing a buffer-to-stencil copy workaround.
Bug: dawn:1389
Change-Id: Ieb23b8d871f14544ef01445a495dc1077274c9f2
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117167
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Loko Kung <lokokung@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
WebGPU clears [pending_map] before resolving or rejecting promises,
which means that the callback for .then or .catch is allowed to unmap,
remap, or do anything with the buffer assuming previous mapping
operations are entirely done the buffer.
Mimic this in Dawn by finishing all operations related to mapping
before calling callbacks they might trigger.
bug: dawn:1619
Change-Id: I9e5b82789a68f28a496a54c31bf9fe0ffde23ccf
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116220
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Takahiro <hogehoge@gachapin.jp>
Reviewed-by: Austin Eng <enga@chromium.org>
Stencil to buffer copies don't capture contents
written in a rendering stage. Copying through an
intermediate texture fixes this problem on Metal Intel.
Add test for the code path that found the issue:
Nonzero-mip stencil copy, discard, then read
Bug: dawn:1389
Change-Id: I63d982df6bace4b5053d3c643b8abda1682490d1
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116851
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Loko Kung <lokokung@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Currently Queue::SubmitImpl() may cause two queue submissions, one is
because of Tick() call which will submit pending commands if there are.
The other one is after converting frontend commands to backend command
buffer. Queue::SubmitImpl() will submit converted commands. However
usually queue submissions are expensive, so merge those two queue
submissions into one by not calling Tick() before converting frontend
commands, so pending commands and recorded commands can be submitted
together. After that, we call Tick() to resolve callbacks and perform
bookkeeping operations (deallocating memory for passed operations,
etc).
Bug: b/265151060
Change-Id: Ia171771bcc1061dc599a58aa6d213a645696fb75
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/116929
Auto-Submit: Peng Huang <penghuang@chromium.org>
Kokoro: Ben Clayton <bclayton@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Peng Huang <penghuang@chromium.org>
Do not transition if the buffer usage is already MapWrite
Change-Id: I16cf68501e19a5b60d6c6f28eaa539df691f14fd
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117240
Reviewed-by: Austin Eng <enga@chromium.org>
Auto-Submit: Peng Huang <penghuang@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Peng Huang <penghuang@chromium.org>
