Assert in each AST constructor that symbols belong to the program of the parent.
Bug: tint:709
Change-Id: I82ae9b23c88e89714a44e057a0272f0293385aaf
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/47624
Commit-Queue: Ben Clayton <bclayton@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: James Price <jrprice@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
SymbolTable::New() used to build and return a symbol without a registered name. When you asked for the name of the symbol it would return tint_symbol_N, where N is the numerical identifier for the symbol.
This approach was a major tripping hazzard for transforms that liked to fetch the source program name, and register it in the new program (in this situation, you should always use `CloneContext::Clone(Symbol)`).
Without special casing for unnamed symbols, you could end up promoting the unnamed symbol to a named symbol, and then colliding against a new unnamed symbol.
This is exactly what happened in tint:711.
Instead, with this change:
* The concept of unnamed symbols has been removed. All symbols now have a name.
* The signature of `SymbolTable::New()` has been changed to take a name parameter (which defaults to 'tint_symbol'). This can be used to create a new, unique named symbol (possibly with a suffix), which will not collide with any existing symbols. Note these symbols may still collide if `SymbolTable::Register()` is called with the same name. All Transforms that currently use `SymbolTable::Register()` will be fixed in another change.
* The CloneContext has been updated to use `SymbolTable::New()` instead of `Register()`. This means that any symbols defined before a clone will not collide.
* `CloneContext::CloneSymbols()` has been added which allows a transform to pre-clone all the symbols from the source program. This can be used to avoid the authored identifiers being suffixed with a number, in the case a transform calls New() before the symbol is cloned.
* `Symbol::to_str()` has been changed to return `$<id>` instead of `tint_symbol_N`. This is to avoid any confusion between the actual name and the symbol ID.
Bug: tint:711
Bug: tint:712
Change-Id: I526e4b49b7027545613859de487e6a275686107a
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/47631
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
This CL adds a table which maps symbols to strings. This will allow us
to remove the use of std::string in the various AST nodes and refer to
the symbols instead.
Change-Id: I902641b3e546a2a44b3b2a39ce4f019cdcbeacc7
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/35100
Commit-Queue: dan sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Auto-Submit: dan sinclair <dsinclair@chromium.org>
Ben Clayton
dan sinclair