If a method / function returns a StringRef but the
variable is of type const std::string& a temporary string is
created (StringRef has a cast operator to std::string),
which is a suboptimal behavior.
Differential revision: https://reviews.llvm.org/D34994
Test plan: make check-all
llvm-svn: 307195
The way the named arguments for various system instructions are handled at the
moment has a few problems:
- Large-scale duplication between AArch64BaseInfo.h and AArch64BaseInfo.cpp
- That weird Mapping class that I have no idea what I was on when I thought
it was a good idea.
- Searches are performed linearly through the entire list.
- We print absolutely all registers in upper-case, even though some are
canonically mixed case (SPSel for example).
- The ARM ARM specifies sysregs in terms of 5 fields, but those are relegated
to comments in our implementation, with a slightly opaque hex value
indicating the canonical encoding LLVM will use.
This adds a new TableGen backend to produce efficiently searchable tables, and
switches AArch64 over to using that infrastructure.
llvm-svn: 274576
Michael Zolotukhin