Parameter PossiblyLoopIndependent has lost its intended purpose. This flag is always set to true in all cases when depends() is called, hence we want to reconsider the utility of this variable and remove it from the function signature entirely. This is an NFC patch.
As part of the "RemoveDIs" work to eliminate debug intrinsics, we're replacing methods that use Instruction*'s as positions with iterators. A number of these (such as getFirstNonPHIOrDbg) are sufficiently infrequently used that we can just replace the pointer-returning version with an iterator-returning version, hopefully without much/any disruption. Thus this patch has getFirstNonPHIOrDbg and getFirstNonPHIOrDbgOrLifetime return an iterator, and updates all call-sites. There are no concerns about the iterators returned being converted to Instruction*'s and losing the debug-info bit: because the methods skip debug intrinsics, the iterator head bit is always false anyway.
As part of the "RemoveDIs" project, BasicBlock::iterator now carries a debug-info bit that's needed when getFirstNonPHI and similar feed into instruction insertion positions. Call-sites where that's necessary were updated a year ago; but to ensure some type safety however, we'd like to have all calls to moveBefore use iterators. This patch adds a (guaranteed dereferenceable) iterator-taking moveBefore, and changes a bunch of call-sites where it's obviously safe to change to use it by just calling getIterator() on an instruction pointer. A follow-up patch will contain less-obviously-safe changes. We'll eventually deprecate and remove the instruction-pointer insertBefore, but not before adding concise documentation of what considerations are needed (very few).
When moving an entire basic block after `InsertPoint`, currently we check each instruction whether their users are dominated by `InsertPoint`, however, this can be improved such that even a user is not dominated by `InsertPoint`, as long as it appears as a subsequent instruction in the same BB, it is safe to move. This patch is similar to commit 751be2a064f119af74c7b9b1e52bc904d8aa114d that enhanced hoisting an entire BB, and this patch enhances sinking an entire BB. Please refer to the added functionality in test case `llvm/unittests/Transforms/Utils/CodeMoverUtilsTest.cpp` that was not supported without this patch.
As outlined in my proposal of how to get rid of debug intrinsics, this patch adds a moveBefore method that signals the caller /intends/ the order of moved instructions is to stay the same. This semantic difference has an effect on debug-info, as it signals whether debug-info needs to move with instructions or not. The patch just replaces a few calls to moveBefore with calls to moveBeforePreserving -- and the latter just calls the former, so it's all NFC right now. A future patch will add an implementation of moveBeforePreserving that takes action to correctly preserve debug-info, but that's tightly coupled with our non-instruction debug-info representation that's still being reviewed. [0] https://discourse.llvm.org/t/rfc-instruction-api-changes-needed-to-eliminate-debug-intrinsics-from-ir/68939 Differential Revision: https://reviews.llvm.org/D156369
These files no longer use llvm::Optional.
This is part of an effort to migrate from llvm::Optional to std::optional: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
This patch mechanically replaces None with std::nullopt where the compiler would warn if None were deprecated. The intent is to reduce the amount of manual work required in migrating from Optional to std::optional. This is part of an effort to migrate from llvm::Optional to std::optional: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716