Polyfill them completely for HLSL.
For the other backends, just add range checks for acosh and atanh.
Fixed: tint:1465
Change-Id: I3abda99b474d9f5ba09abf400381467dc28ea0bd
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/94380
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Auto-Submit: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
dan sinclair