This reverts commit 11d09f2fe7.
Reason for revert: Failing roll of Tint to Dawn: https://dawn-review.googlesource.com/c/dawn/+/70100
Original change's description:
> HLSL: force FXC to never unroll loops
>
> 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>
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: tint:1112
Change-Id: I8e8f3c0abfa6e6bc5d0e67af9428a46ef867d5c1
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/70540
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
bc5d8f6bcf