Handle access control on var declarations instead of via [[access]]
decorations. This change does the minimal work to migrate the WGSL
parser over to the new syntax. Additional changes will be needed
to correctly generate defaulted access qualifiers, as well as
validating access usage.
The [[access]] decorations are still supported by the WGSL parser,
with new deprecated warnings, but not for aliases. Example:
var x : [[access(x)]] alias_to_struct;
Making this work is far more effort than I want to dedicate to backwards
compatibility, and I do not beleive any real-world usage will be doing
this.
Still TODO:
* Adding access control as the optional, third parameter to ptr<>.
* Calculating default accesses for the various storage types.
* Validating usage of variables against the different accesses.
Bug: tint:846
Change-Id: If8ca82e5d16ec319ecd01f9a2cafffd930963bde
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/53088
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: James Price <jrprice@google.com>
Reviewed-by: David Neto <dneto@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
This change implements pointers and references as described by the WGSL
specification change in https://github.com/gpuweb/gpuweb/pull/1569.
reader/spirv:
* Now emits address-of `&expr` and indirection `*expr` operators as
needed.
* As an identifier may now resolve to a pointer or reference type
depending on whether the declaration is a `var`, `let` or
parameter, `Function::identifier_values_` has been changed from
an ID set to an ID -> Type* map.
resolver:
* Now correctly resolves all expressions to either a value type,
reference type or pointer type.
* Validates pointer / reference rules on assignment, `var` and `let`
construction, and usage.
* Handles the address-of and indirection operators.
* No longer does any implicit loads of pointer types.
* Storage class validation is still TODO (crbug.com/tint/809)
writer/spirv:
* Correctly handles variables and expressions of pointer and
reference types, emitting OpLoads where necessary.
test:
* Lots of new test cases
Fixed: tint:727
Change-Id: I77d3281590e35e5a3122f5b74cdeb71a6fe51f74
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/50740
Commit-Queue: Ben Clayton <bclayton@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: David Neto <dneto@google.com>
Ben Clayton