This change is a preparation for making the compute pass track the
synchronization scope usages per dispatch instead of for the whole pass.
- Split the tracking of render and compute passes usages.
- Rename PassTextureUsage to TextureSubresourceUsage since is it not
per-pass
- Add SyncScopeResourceUsage as a subclass of PassResourceUsage to
start modifying some of the code to work with synchronization scopes
(even if syncscope == pass at the moment).
There are no functional changes.
Bug: dawn:632
Change-Id: Ieeb6d70a44dc1c726f26989eebcd87e63e732785
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/49883
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
This is in preparation for a change that will change all the
CreateFooInternal to be CreateFoo so they can be called in a
reentrant manner without special refcounting.
This also standardizes all the backends (except OpenGL and Null)
to use Object::Create that returns a Ref<T> or ResultOrError<Ref<T>>,
something we wanted to do for a long time.
Bug: dawn:723
Change-Id: I9e0baced333ffeb0affbc6a276c9bd9de082263a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/46440
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Still leave deprecated `depth` functional as there are some references in
other clients. Using `depth` and `depthOrArrayLayers` at the same time is
invalid. Add DeprecatedAPITests.
Bug: chromium:1176969
Change-Id: Ia06645e4f3c17588323dd36b11f9f3988b2e3aba
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/44640
Commit-Queue: Shrek Shao <shrekshao@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Removes special casing depth-stencil or multi-planar formats.
Like depth-stencil, NV12 views can be created but not sampled.
BUG=dawn:551
Change-Id: I3cd43d079253f4ee45660d0efd2723e1650f88d3
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/41342
Commit-Queue: Bryan Bernhart <bryan.bernhart@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Bryan Bernhart <bryan.bernhart@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Adds support for NV12 texture format and per plane view aspects.
Only allows planar sampling of imported DX11 textures. See usage
tests for examples and formats.h for rules.
Bug: dawn:551
Change-Id: I44b89d2c07bb9969638e77ce7c756ef367167f0c
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/38781
Commit-Queue: Bryan Bernhart <bryan.bernhart@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
The global resource usage was used for two things:
- Validating that the texture had the required usage, but this was
removed in a previous commit in favor of checking the texture's usage at
the encoding entrypoint.
- Skipping laz-clearing of the texture if it was used as
RenderAttachment. This was incorrect and would skip clearing of all of
the texture's subresource as long as one of them was used as
RenderAttachment.
This commit make PassTextureUsage exactly a
SubresourceStorage<TextureUsage> and fixes the logic for skipping
the clearing or RenderAttachment. It also adds a regression test for the
lazy clearing fix.
Bug: dawn:635
Change-Id: I5d984febb3e5a5f9ae15b632cac68e294555c4e6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/38382
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Vulkan requires that storage images be in the GENERAL layout, and requires
that we choose a layout at VkDescriptorSet creation. This means that
since Sampled+ROStorage texture may sometimes be used as both usages in
the same pass, they must always be in the GENERAL layout even for
SampledTexture bindings.
Fix this by looking at the texture's creation usage in VulkanImageLayout
for wgpu::TextureUsage::Sampled.
Also add a regression test that triggers a Vulkan Validation Layer error
without this fix.
Bug: dawn:635
Change-Id: I4a5b94e1af20839b3b8cc080d36fca59d79f09bb
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/38107
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Using this container is a small performance regression in the simple
cases where all subresources are the same, or when the texture has few
subrsources. However it give better performance in the hard subresource
tracking cases of textures with many subresources.
Using SubresourceStorage also makes it easier to work with compressed
storage since the compression is mostly transparent. It reduces code
duplication and prevent bugs from appearing when a developer would
forget to handle compression.
This fixes a state tracking issue in ValidatePassResourceUsage where the
function didn't correctly handle the case where the PassResourceUsage
was compressed.
Also removes the unused vulkan::Texture::TransitionFullUsage.
Also makes SubresourceStorage<T> only require operator== on T and not
operator !=.
Also fixes the texture format's aspect being used to create pipeline
barriers instead of the range's aspects.
Bug: dawn:441
Change-Id: I234b8191f39a09b541c1c63a60cccd6cee970550
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/37706
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
One of the helper methods to compute texture barriers didn't handle the
kReadOnlyStorage usage, which made barriers issued too small.
Issue was caught by running
StorageTextureZeroInitTests.ReadonlyStorageTextureClearsToZeroInRenderPass
with the Vulkan barrier validation enabled.
Also renames kReadonlyStorageTexture to kReadOnlyStorageTexture for
consistency.
Bug: dawn:635
Change-Id: I6e6027c380672dcdaea789c811665536b446003e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/38101
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
This will allow using the same logic for other kinds of smartpointers,
like NSRef<>
Bug: dawn:89
Change-Id: Idbe08208fdb38b236f52635bc913162e60baf0f0
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/32160
Reviewed-by: Stephen White <senorblanco@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
This helper function makes the code easier to read because the name
encodes the semantic of the operation compared to the bit-twiddling that
it replaces.
Bug: None
Change-Id: Iab587e04a91cf60acf8920de1f20bb55f3ea3816
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/31668
Reviewed-by: Stephen White <senorblanco@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
In Vulkan the swapchain can stop working if the window resizes and
doesn't match the size of the swapchain images anymore. WebGPU
applications might not handle resizes instantly, so if the swapchain
becomes incompatible we give them a temporary texture that we'll then
blit inside the real swapchain texture.
This also handles the case where the application requires more usages
than what the swapchain can support.
In addition, temporary checks are added that fail swapchain creation if
the VkSurface doesn't support BGRA8Unorm which is the only allowed
format for WebGPU swapchains at the moment.
SwapChainTests should now work on Vulkan and are enabled.
Bug: dawn:269
Change-Id: I812c0653125ed86d3a0f8f67347e961c7b207a98
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/30700
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
And deprecate using ::Float in the bind group layout for
"shadow textures" in the pipeline (along with a deprecation test).
Adds the ability to be used with DepthComparison only to depth textures,
this could potentially a breaking change if users where doing
depth-comparison on float32 textures but that's not supported in WebGPU.
Bug: dawn:527
Change-Id: Ib28b0443e3002e0aa2811713b9e843c2417e13e7
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/30240
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
This also introduces a per-aspect supportedComponentTypes that exactly
mirrors baseType for now but will contain additional bits in the future
(like DepthComparison for depth textures).
It is also a step towards being able to create single-aspect view of
depth-stencil textures to sample either the depth or the stencil
component.
Bug: dawn:527
Change-Id: I3ab224d07c136c682cc2993b9a8599237d318130
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/30103
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
A lot of our switches over enum values use the following pattern:
default:
UNREACHABLE();
return foo;
This is problematic because when adding a new value to one of the WebGPU
enums, there is no compilation error for switches that are missing it.
Currently we're supposed to write code and tests and fix UNREACHABLEs when
we see them.
Instead we should strive to have most switches on enums to be complete
and explicitily tag unreachable values as UNREACHABLE. Some switches
might still want to use default: UNREACHABLE() if only a couple values
need to be handled out of very many.
In this CL we go through all the UNRAECHABLEs and change them if need
be. Also an ErrorQueue class is added to avoid having
QueueBase::SubmitImpl just be UNREACHABLE (and force overriding
instead).
Bug: dawn:527
Change-Id: I33dfb4703104912cc5f001f9faf907a61324de68
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/28501
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
Returning the layouts from an export operation and then using
them in a subsequent import operation allows the import to preserve
the texture contents.
This fixes Vukan image wrapping on some AMD/NVIDIA devices.
Bug: dawn:200
Change-Id: Icbb6e759856d410bb69724b9f439bc3088756d19
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/28380
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
This patch combines all the resource barriers added before each
dispatch() into one call to reduce the number of
vkCmdPipelineBarrier() in the Vulkan command buffer.
BUG=dawn:522
Change-Id: I1b5943e62eb0a09db96de12196fcabb3448e9e4d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/28283
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Previously, this code path was gated on whether or not the texture
format is renderable. This should not be the case as this Vulkan
command only requires the texture to have TRANSFER_DST.
Bug: dawn:145
Change-Id: Ifd8f75a70477a8d159c04d1180247cd076c767bc
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/27941
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
When using a dynamic uploader we didn't align the offset
that the allocated memory might have already had.
That fixes WriteTexture, WriteBuffer, ClearTexture and
on D3D12 ClearBuffer.
Bug: dawn:512
Change-Id: I64c7511ad6b0d3d6a28a494e1324a10ad4d38091
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/27020
Commit-Queue: Tomek Ponitka <tommek@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
Also update RG11B10Float to be name RG11B10Ufloat
Bug: dawn:22
Change-Id: I0ea76dc25c37ebaeb4c2c2c2a119d00940acc145
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/25760
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
Previously, lazy clearing always added DEPTH_STENCIL or RENDER_TARGET to
textures because we cleared using ClearDepthStencilView or
ClearRenderTargetView. Now, we're able to clear using copies.
This also allows textures to actually use the small resource heap
placement optimization. Doing so generates debug layer warnings when the
small alignment is first tried but rejected. This CL silences those
warnings.
Bug: dawn:145
Change-Id: Id385846536b337cddcfdadc5739561c7adc30c8c
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/26840
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
This enables depth-stencil textures to track per aspect state
independently. It lifts the restriction that depth and stencil
store ops must be the same as they now have independent clear
states. It will also enable correct barriers on Vulkan and D3D12.
Bug: dawn:439
Change-Id: I8a73187df57a1d7eee6790cb4395bdecf42b63aa
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/26127
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
Commit-Queue: Austin Eng <enga@chromium.org>
Format::aspect should be a mask so that it is easier to iterate over
and test if an aspect is present.
This CL also re-exports wgpu's EnumClassBitMask helpers in dawn_native.
It also adds an EnumMaskIterator which wraps BitSetIterator to allow
iterating over the enums in an enum mask.
Bug: dawn:439
Change-Id: I08180a45b27c6031e2f80b0fa1801716677fd813
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/24682
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
Commit-Queue: Austin Eng <enga@chromium.org>
Also fix a misuse of VkBufferImageCopy that caused some Swiftshader
failures.
Bug: dawn:22
Change-Id: Ie812a590d70c7561dfcf2f78ce6c530187610e65
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23200
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
If a texture's old states of all subresources are the same, and its
new states are the same too, then we can use one barrier to transit
states for all subresources. We don't need to use one barrier per
each subresource.
This change can reduce barriers we dispatched, in order to improve
performance for particular situations.
Bug: dawn:441
Change-Id: I9fe9dabda725e05d4ce5a8e69ee7b40e6724a22a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23145
Commit-Queue: Yunchao He <yunchao.he@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
This patch put subresource related variables like baseMipLevel,
levelCount, baseArrayLayer, layerCount into a single struct at
backends.
Bug: dawn:157
Change-Id: I50c6bb0ed8ae7a184506c23cab4b64a472bbd75e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23163
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Yunchao He <yunchao.he@intel.com>
This makes the tracking in TextureBase match the shape of
wgpu::TextureDescriptor.
GetSize() becomes a bit more surprising because the depth can sometimes
be the array size, so new getters GetWidth(), GetHeight() and GetDepth()
are added.
Some simplifications to the backend texture creation code are included
that will make it less error prone to add support for 1D / 3D textures.
Bug: dawn:22
Change-Id: I33b6ca99af9d58fc88f5f626cfd5e2e62a8b45cb
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23103
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
This updates CL:
- Adds a deprecation warning to use size.depth instead of
arrayLayerCount.
- Changes all tests and samples to use size.depth.
- Adds deprecation tests for the change.
In particular the state tracking in TextureBase isn't changed yet
because it requires non-trivial changes in the backends. It will be done
in a follow-up CL.
Bug:dawn:22
Change-Id: Ic02dfb5baaba8d5b06cd339ce988e9b1d16cb5e9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23101
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
When we do transition barriers for a texture view outside of a pass
(say copy, clear, initialization), if the texture view can cover all
subresources, and its old usages across all subresources are the
same, then we can use one transition barrier. We don't need to use
separate barrier per each subresource.
This patch can reduce barrier we delivered, and improve performance
for particular situations.
Bug: dawn:441
Change-Id: I2ae9b39793915553cbaaceacaf58bf87c9ba3bc6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23129
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Yunchao He <yunchao.he@intel.com>
This patch put subresource related variables like baseMipLevel,
levelCount, baseArrayLayer, layerCount into a single struct at
front-end. We have a lot more at backend too, a following patch
will do that.
Bug: dawn:157
Change-Id: Iab5633a4246b6ae89b80c39f5672dbb31d7a3e78
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/22704
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Yunchao He <yunchao.he@intel.com>
If a texture follow this rule:
* old usages of all subresources are the same
* new usages of all subresources are the same
Then we can use one barrier to transit states for all subresources.
We don't need to use one barrier per each subresource.
This patch adds a flag at front-end to capture many (but not all)
situations which follow the rule above, then we don't need to loop
over every subresource at Vulkan backend.
Bug: dawn:441
Change-Id: I6124ee2cb09c9142fefd8f057dc6d2659301e2d4
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/22702
Commit-Queue: Yunchao He <yunchao.he@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
This patch combines barriers in a render/compute pass into one
function call.
Previously, we need to dispatch barrier(s) for each buffer/texture
in a pass. So we may need quite a lot function calls to deliver
barriers in a pass in real web applications. One example is that
we did see that too many function calls to deliver barriers in
Aquarium (WebGPU porting) contributed to CPU usage and bottleneck.
Bug: dawn:441
Change-Id: Ibe44967fefd2e1e6e64df4587146c4fb7fbe8e73
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/22700
Commit-Queue: Yunchao He <yunchao.he@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
This change implemented texture subresource on Vulkan. It added a new
function to handle barriers for texture subresource for bind groups.
It also simplified barriers which are set for texture clear and copy.
Before this patch, all barriers are done upon all mip levels and all
array layers. With this patch, barriers are done upon particular mip
level(s) and array layer(s).
We may need more texture subresource end2end tests for copy and clear
opterations. I will visit that later.
Bug: dawn:157
Change-Id: Ie2247c6315326494f2d3736334e84b2867a16c17
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/22024
Commit-Queue: Yunchao He <yunchao.he@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Configure was transitioning the swapchain images from undefined to
present layout but this was already happening because TextureVk starts
with a mLastUsage of None that will force a transition from undefined
when used.
Also introduce an internal texture usage bit kPresentTextureUsage to
prepare for the eventual remove of wgpu::TextureUsage::Present when
old swapchains are removed.
Bug: dawn:269
Change-Id: I57d26f18e34cacd5d91419a45787b2ece9558846
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/20881
Reviewed-by: Stephen White <senorblanco@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
This aligns this constructor to be used via Create like the other
vulkan::Texture constructors.
Bug: dawn:269
Change-Id: Ib85874bf24bfe49b644b4faa63c9248c540811c8
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/20882
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
This patch adds the basic supports of read-only and write-only storage
textures on Vulkan.
The subresource tracking and barriers on the subresources used as
read-only and write-only storage textures are not included in this
patch.
BUG=dawn:267
TEST=dawn_end2end_tests
Change-Id: I6831b96202a97182763ecd28bc41ab03df904a7c
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/20560
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Reviewed-by: Austin Eng <enga@chromium.org>
To avoid accidental memory leaks on account of using raw pointers,
use Ref<TextureBase> as method return type except at Dawn interface
boundaries.
Change-Id: I6459062ee28984de2cb1d5a2059bc70cf82b2faf
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/19580
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>
RefCounted (and derived) destructors should be protected on the class
to ensure the objects can ONLY be destructed by calling Release. This
avoids errors cause by destroying objects out from under code which
has an active reference count.
Unfortunately, many of the 'base' classes must continue having public
destructors because they are used as "blueprint" objects created on
the stack.
Added final on most-derived classes.
Ideas for future improvement:
- Change "base" objects to have protected destructors but create new
blueprint objects that privately derive from base objects. This
limits the blueprint object's usefulness to only be a blueprint.
- Modify createX methods to return Ref<Object> instead of Object*
Change-Id: I6f3b3b178118d135c4342cb912e982a3873d71af
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/18780
Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Overriding VK_DEFINE_NON_DISPATCHABLE_HANDLE changes the function
signatures of Vulkan functions, changing their ABI and making us
incompatible with real drivers. This removes that magic, and replaces it
with an explicit wrapper, VkHandle, which has much of the same
functionality as the original VkNonDispatchableHandle.
It adds definitions for dawn_native::vulkan::VkBuffer et al, which
shadow the native ::VkBuffer et al. This retains type safety throughout
the Vulkan backend without changing every single usage.
Notably, the following things had to change:
- An explicit conversion from VkBuffer* to ::VkBuffer* is needed for
arrays. This is implemented as a reinterpret_cast, which is still
safe as the new VkHandle still has the same memory layout properties
as VkNonDispatchableHandle did.
- When pointing to a VkHandle as an output pointer, it's now necessary
to explicitly get the native ::VkBuffer (via operator*) and point to
it.
Previously reviewed on:
https://dawn-review.googlesource.com/c/dawn/+/15580
Bug: chromium:1046362
Change-Id: I7d34ec38a805025f92165ea9a7ee07ae5c182076
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/15641
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
