Emit the "[loop]" attribute on "for" and "while" so that FXC does not
attempt to unroll them. This is to work around an FXC bug where it fails
to unroll loops with gradient operations.
FXC ostensibly unrolls such loops because gradient operations require
uniform control flow, and loops that have varying iterations may
possibly not be uniform. Tint will eventually validate that control flow
is indeed uniform, so forcing FXC to avoid unrolling in these cases
should be fine.
Bug: tint:1112
Change-Id: I10077f8b62fbbb230a0003f3864c75a8fe0e1d18
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/69880
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
This removes a lot of awkward logic from the MSL writer, and means
that we now handle all module-scope variables with the same transform.
Change-Id: I782e36a4b88dafbc3f8364f7caa7f95c6ae3f5f1
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/67643
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Change ast::Array to use an ast::Expression for its `size` field. The
WGSL frontend now parses the array size as an `primary_expression`,
and the Resolver is responsible for validating the expression is a
signed or unsigned integer, and either a literal or a non-overridable
module-scope constant.
The Resolver evaluates the constant value of the size expression, and
so the resolved sem::Array type still has a constant size as before.
Fixed: tint:1068
Fixed: tint:1117
Change-Id: Icfa141482ea1e47ea8c21a25e9eb48221f176e9a
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/63061
Auto-Submit: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
MSL vectors with other widths already match WGSL's rules for alignment
and size.
Change-Id: I237052372463ea8323eab47c3b4ca90c6d8afcc3
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/62600
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Add `transform::DecomposeStridedMatrix`, which replaces matrix members of storage or uniform buffer structures, that have a [[stride]] decoration, into an array
of N column vectors.
This is required to correctly handle `mat2x2` matrices in UBOs, as std140 rules will expect a default stride of 16 bytes, when in WGSL the default structure layout expects a stride of 8 bytes.
Bug: tint:1047
Change-Id: If5ca3c6ec087bbc1ac31a8d9a657b99bf34042a4
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/59840
Reviewed-by: David Neto <dneto@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>