Change FileCheck to accept patterns like "[[[var...]]" and treat the
excess open brackets at the start as literals.
This makes the patterns for matching assembler output with literal
brackets much cleaner. For example an AMDGPU pattern that used to be
written like:
buffer_store_dwordx2 v{{\[}}[[LO]]:[[HI]]{{\]}}
can now be:
buffer_store_dwordx2 v[[[LO]]:[[HI]]]
(Even before this patch the final close bracket did not need to be
wrapped in {{}}, but people tended to do it anyway for symmetry.)
This does not introduce any ambiguity since "[[" was always followed by
an identifier or '@' or '#', so "[[[" was always an error.
I've included a few test updates in this patch just for illustration and
testing. There are a couple of hundred tests that could be updated as a
follow up, mostly in test/CodeGen/.
Differential Revision: https://reviews.llvm.org/D117117
Change-Id: Ia6bc6f65cb69734821c911f54a43fe1c673bcca7
; CHECK: [[VAR:[a-z]]]
The problem was that to find the end of the regex var definition, it was
simplistically looking for the next ]] and finding the incorrect one. A
better approach is to count nesting of brackets (taking escaping into
account). This way the brackets that are part of the regex can be discovered
and skipped properly, and the ]] ending is detected in the right place.
llvm-svn: 169109
Jay Foad