LR was undefined entering outlined functions that contain calls. This made the
machine verifier unhappy when expensive checks were enabled. This fixes that.
llvm-svn: 321014
The outliner previously would never outline calls. Calls are pretty common in
files, so it makes sense to outline them. In fact, in the LLVM test suite, if
you count the number of instructions that the outliner misses when you outline
calls vs when you don't, it turns out that, on average, around 6% of the
instructions encountered are calls. So, if we outline calls, we can find more
candidates, and thus save some more space.
This commit adds that functionality and updates the mir test to reflect that.
llvm-svn: 320229
The offset overflow check before was incorrect. It would always give the
correct result, but it was comparing the SCALED potential fixed-up offset
against an UNSCALED minimum/maximum. As a result, the outliner was missing a
bunch of frame setup/destroy instructions that ought to have been safe to
outline. This fixes that, and adds an instruction to the .mir test that
failed the old test.
llvm-svn: 320090
This commit allows the outliner to avoid saving and restoring the link register
on AArch64 when it is dead within an entire class of candidates.
This introduces changes to the way the outliner interfaces with the target.
For example, the target now interfaces with the outliner using a
MachineOutlinerInfo struct rather than by using getOutliningCallOverhead and
getOutliningFrameOverhead.
This also improves several comments on the outliner's cost model.
https://reviews.llvm.org/D36721
llvm-svn: 314341
Before, the outliner would mark all instructions that read from/modify LR as
illegal. This doesn't handle W30, which overlaps with LR. This shouldn't be
outlined.
This commit fixes that by making modifiesRegister() and readsRegister() look at
W30 + take in a TRI argument. This makes sure that modifiesRegister() and
readsRegister() won't outline either of W30 and LR.
https://reviews.llvm.org/D36435
llvm-svn: 310422
Jessica Paquette