1. [TableGen] Add the !substr() bang operator (details)
Commit 3a675c777dd5788e2313cb06fb27b01f8a2e7573 by paul
[TableGen] Add the !substr() bang operator

Update the documentation and add a test.

Differential Revision:
The file was modifiedllvm/lib/TableGen/Record.cpp
The file was addedllvm/test/TableGen/
The file was modifiedllvm/lib/TableGen/TGParser.cpp
The file was modifiedllvm/lib/TableGen/TGLexer.h
The file was modifiedllvm/lib/TableGen/TGParser.h
The file was modifiedllvm/docs/TableGen/ProgRef.rst
The file was modifiedllvm/lib/TableGen/TGLexer.cpp
The file was modifiedllvm/include/llvm/TableGen/Record.h