tree 3ef35f9d7f118d21b032a1e118a703f7d0fbcb4e
parent f42b90dbe1f3ad5aee6ef45008f84c27eef7db46
author Ben Clayton <bclayton@google.com> 1608035538 +0000
committer Commit Bot service account <commit-bot@chromium.org> 1608035538 +0000

ast: Clone symbols instead of ever-growing

The interface for cloning a module was made significantly more complex in https://dawn-review.googlesource.com/c/tint/+/35502/ as some of the transforms required constructing symbols before the clone. This was temporary solution in 35502 was to copy the symbol table, then construct the new types, then perform the clone. This lead to a really messy callback interface, that was extremely error prone (e.g. lamda-capturing stack variables from the initializer callback that had been unwound).

Instead, clone the symbols as they're encountered. This may produce an entirely different set of identifiers, but no longer ever-grows the symbol list, and keeps the interface clean.

Bug: tint:396
Bug: tint:390
Change-Id: I54affd68ac3b730b649af9b47eba685c8a1d784a
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/35663
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: dan sinclair <dsinclair@chromium.org>