The only reason why BranchPropagatedUser existed was because early on in SIL, we
weren't sure if cond_br should be able to handle non-trivial values in
ossa. Now, we have reached the point where we have enough experience to make the
judgement that it is not worth having in the representation due to it not
holding its weight.
Now that in ToT we have banned cond_br from having non-trivial operands in ossa,
I can just eliminate BranchPropagatedUser and replace it with the operands that
we used to construct them!
A few notes:
1. Part of my motiviation in doing this is that I want to change LiveRange to
store operands instead of instructions. This is because we are interested in
being able to understand the LiveRange at a use granularity in cases where we
have multiple operands. While doing this, I discovered that I needed
SILInstructions to use the Linear Lifetime Checker. Then I realized that now was
the time to just unwind BranchPropagatedUser.
2. In certain places in SemanticARCOpts, I had to do add some extra copies to
transform arrays of instructions from LiveRange into their operand form. I am
going to remove them in a subsequent commit when I change LiveRange to work on
operands. I am doing this split to be incremental.
3. I changed isSingleInitAllocStack to have an out array of Operand *. The only
user of this code is today in SemanticARCOpts and this information is fed to the
Linear Lifetime Checker, so I needed to do it.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Avoid emitting unnecessary basic block for cleanup chains. This is a
general approach that handles all cases while simplifying SILGen
emission and keeping the CFG in a valid state during SILGen.
