It avoids that a pass runs a second time if didn't make any changes in the previous run and no other pass changed the function in between.
rdar://problem/20336764
In this change I also removed the CompleteFunctions analysis which is now obsolete.
Some measurements with swiftbench (-wmo, single threaded):
It reduces the number of pass runs by about 28%. Because only passes are skipped that don't do anything, the effect on compile time is not so dramatic.
The time spent in runSILOptimizationPasses is reduced by ~9% which gives a total compile time reduction of about 3%.
Swift SVN r26757
To set the PassKind automatically, I needed to refactor some code of the pass manager and the pass definitions.
The main changes are:
1) SILPassManager now has an add-function for each pass: PM.add(createP()) -> PM.addP()
2) I removed the ARGS argument in Passes.def, which we didn't use anyway.
Swift SVN r26756
The old invalidation lattice was incorrect because changes to control flow could cause changes to the
call graph, so we've decided to change the way passes invalidate analysis. In the new scheme, the lattice
is replaced with a list of traits that passes preserve or invalidate. The current traits are Calls and Branches.
Now, passes report which traits they preserve, which is the opposite of the previous implementation where
passes needed to report what they invalidate.
Node: I tried to limit the changes in this commit to mechanical changes to ease the review. I will cleanup some
of the code in a following commit.
Swift SVN r26449
Currently no passes implement this, but I am going to add support to the
callgraph. I just ran into a callgraph bug that this would have helped
to catch.
rdar://19930214
Swift SVN r25514
Revert "For debugging purposes allow passes to stop any more passes from running by calling PassManager::stopRunning()."
This reverts commit r20604.
This reverts commit r20606.
This was some debugging code that snuck in.
Swift SVN r20615
In the current setup analysis information is not reused by new pass managers.
There is no point in having different pass managers. Instead, we can just remove
transformations, reset the internal state of the pass manager, and add new
transformation passes. Analysis information can be reused.
Reuse one pass manager in the pass pipeline so that we don't have to
unnecessarily recompute analysis information.
Swift SVN r19917
PassManager.
I think this is much cleaner and more flexible. The various pass
builders have no business marshalling these things around, and they
shouldn't be bound to the pass C'tor. In the future we will be able
override and dynamically modify pass configuration this way.
Swift SVN r13626
Now the pass does not need to know about the pass manager. We also don't have
runOnFunction or runOnModule anymore because the trnasformation knows
which module it is processing. The Pass itself knows how to invalidate the
analysis, based on the injected pass manager that is internal to the
transformation.
Now our DCE transformation looks like this:
class DCE : public SILModuleTransform {
void run() {
performSILDeadCodeElimination(getModule());
invalidateAnalysis(SILAnalysis::InvalidationKind::All);
}
};
Swift SVN r13598
