This revision introduces the ability to invoke mem2reg as a rewrite pattern. This also modified the canonical mem2reg pass to use the rewrite pattern approach.
Depends on D149825
Reviewed By: gysit
Differential Revision: https://reviews.llvm.org/D149958
This patch refactors the Mem2Reg infrastructure. It decouples
analysis from promotion, allowing for more control over the execution of
the logic. It also adjusts the interfaces to be less coupled to mem2reg
and more general. This will be useful for an upcoming revision
introducing generic SROA.
This commit reverts f333977eb20a and relands 91cff8a71872.
The original commit was reverted accidentally due to a misinterpretation
of a bazel build bot failure.
Reviewed By: gysit
Differential Revision: https://reviews.llvm.org/D149825
This patch refactors the Mem2Reg infrastructure. It decouples
analysis from promotion, allowing for more control over the execution of
the logic. It also adjusts the interfaces to be less coupled to mem2reg
and more general. This will be useful for an upcoming revision
introducing generic SROA.
Reviewed By: gysit
Differential Revision: https://reviews.llvm.org/D149825
This patch introduces a generic implementation of mem2reg on
unstructured control-flow, along with a specialization for LLVM IR. This
is achieved by defining three new interfaces, representing 1. allocating
operations, 2. operations doing memory accesses, 3. operations that can
be rewired and/or deleted to stop using a specific use.
The file containing the core implementation of the algorithm
(`Mem2Reg.cpp`) contains a detailed explanation of how the algorithm
works. The contract for this pass is that given a memory slot with a
single non-aliased pointer, the pass will either remove all the uses of
the pointer or not change anything.
To help review this patch, I recommend starting by looking at the
interfaces defined in `Mem2Reg.td`, along with their reference
implementation for LLVM IR defined in `LLVMMem2Reg.cpp`. Then, the core
algorithm is implemented in `Mem2Reg.cpp`.
If this is all good I also have an implementation of the interfaces for
0-dimensional memref promotion that I can upstream afterwards.
Reviewed By: gysit
Differential Revision: https://reviews.llvm.org/D148109
