AMDGPU/LoadStoreOptimizer: combine MMOs when merging instructions
Summary:
The LoadStoreOptimizer was creating instructions with 2
MachineMemOperands, which meant they were assumed to alias with all other instructions,
because MachineInstr:mayAlias() returns true when an instruction has multiple
MachineMemOperands.
This was preventing these instructions from being merged again, and was
giving the scheduler less freedom to reorder them.
Reviewers: arsenm, nhaehnle
Reviewed By: arsenm
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65036
llvm-svn: 367237