If analyzeBranch fails, on some targets, the out parameters point to
some blocks in the function. But we can't use that information, so make
sure to clear it out. (In some places in IfConversion, we assume that
any block with a TrueBB is analyzable.)
The change to the testcase makes it trigger a bug on builds without this
fix: IfConvertDiamond tries to perform a followup "merge" operation,
which isn't legal, and we somehow end up with a branch to a deleted MBB.
I'm not sure how this doesn't crash the compiler.
Differential Revision: https://reviews.llvm.org/D67306
llvm-svn: 371434
The code was incorrectly counting the number of identical instructions,
and therefore tried to predicate an instruction which should not have
been predicated. This could have various effects: a compiler crash,
an assembler failure, a miscompile, or just generating an extra,
unnecessary instruction.
Instead of depending on TargetInstrInfo::removeBranch, which only
works on analyzable branches, just remove all branch instructions.
Fixes https://bugs.llvm.org/show_bug.cgi?id=43121 and
https://bugs.llvm.org/show_bug.cgi?id=41121 .
Differential Revision: https://reviews.llvm.org/D67203
llvm-svn: 371111
Eli Friedman