Victor A. Ying

[runtime_lib] Add padding to avoid false sharing and preallocate some space to reduce reallocation

1

In Swarm's VertexFrontierList

This us a fairly mechanical transformation to the generated C++: - Add local variable definitions at the top of the lambda body to extract the fields from the struct. -...

[InstCombine] May make task closures large by sinking instructions from parent to child tasks

2

`InstructionCombining` sinks any instruction it can if that instruction is only used in a single successor of it's current basic block: https://github.com/wsmoses/Tapir-LLVM/blob/2031611b65d67c1986af06c5f98b3c1d5e140d51/lib/Transforms/InstCombine/InstructionCombining.cpp#L2946-L2955 This presents significant problems for me, when compiling...

serializeTrivialDetachedBlock() doesn't check that the block it is serializing is really detached by the preceding detaches.

4

I just diagnosed a Swarm compiler crash and am wondering if there are any invariants that would prevent a similar crash from happening in Tapir, or you would want a...

Broken/dead code for finding reattach points for moving static allocas in extractDetachBodyToFunction()

3

In `extractDetachBodyToFunction()`, early on, the reattaches for the current detach are changed to branches: https://github.com/wsmoses/Tapir-LLVM/blob/1482504e234a65bffc8c54de8de9fc877822345d/lib/Transforms/Tapir/TapirUtils.cpp#L258-L263 Later in the function, we search for actual `ReattachInst`s for determining the exit points of...

Why does inferattrs run before and after lowering?

1

The `-inferattrs` pass is run both before and after lowering: https://github.com/wsmoses/Tapir-LLVM/blob/89bb9a7ebb000b3e1a44405872cfef37e7ae679e/lib/Transforms/IPO/PassManagerBuilder.cpp#L741 I am wondering why this is. Note that this is distinct from the `-functionattrs` pass that can deduce attributes...

Is there a design reason that `LoopSpawning`, at several points, checks the return value of `verifyFunction()` and, if the verification fails, it merely returns `false` indicating it did not transform...