Progress:
In progressChanges

Summary

  1. [DAGCombiner] Add test exposing bug in DAG combine. (details)
  2. [DAGCombiner] Fix DAG combine store elimination, different address space. (details)
  3. Revert "[SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics" (details)
Commit 4b00ffa767fc8a71c2eaf544cb6397f6db34eb6a by hgreving
[DAGCombiner] Add test exposing bug in DAG combine.

Adds a test in X86, exposing a bug in DAG combine eliminating stores that
are the same value but no the same address space.

Differential Revision: https://reviews.llvm.org/D102243
The file was addedllvm/test/CodeGen/X86/dagcombine-dead-store.ll
Commit 762ac725bf9775536dda5b3dda13574f14a8c2b9 by hgreving
[DAGCombiner] Fix DAG combine store elimination, different address space.

Fixes a bug in the DAG combiner that eliminates the stores because it missed
to inspect the address space of the pointers.

%v = load %ptr_as1
// no chain side effect
store %v, %ptr_as2

As well as

store %v, %ptr_as1
store %v, %ptr_as2

Fixes a test for above in X86.

Differential Revision: https://reviews.llvm.org/D102096
The file was modifiedllvm/test/CodeGen/X86/dagcombine-dead-store.ll
The file was modifiedllvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
Commit 8d37411e48202b490c62ee3548df4b90f5974e12 by stefanp
Revert "[SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics"

This reverts commit 6c80361b8474535852afb2f7201370fb5f410091.
Breaks PowerPC Big Endian buildbots.
The file was modifiedllvm/test/CodeGen/PowerPC/atomics-i16-ldst.ll
The file was modifiedllvm/test/CodeGen/PowerPC/atomics-i32-ldst.ll
The file was modifiedllvm/test/CodeGen/RISCV/atomic-signext.ll
The file was modifiedllvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
The file was modifiedllvm/lib/Target/WebAssembly/WebAssemblyInstrAtomics.td
The file was modifiedllvm/test/CodeGen/PowerPC/atomics-i8-ldst.ll
The file was modifiedllvm/test/CodeGen/Mips/atomic.ll
The file was modifiedllvm/test/CodeGen/PowerPC/atomics-i64-ldst.ll