Merge pull request dotnet/coreclr#7677 from CarolEidt/StructOpts

Enable optimization of structs

Commit migrated from https://github.com/dotnet/coreclr/commit/9c95461a7200b9df71e8b76963fe072d6fb9c39b

diff --cc src/coreclr/src/jit/codegenlegacy.cpp
Simple merge

diff --cc src/coreclr/src/jit/codegenxarch.cpp
Simple merge

diff --cc src/coreclr/src/jit/compiler.h
Simple merge

diff --cc src/coreclr/src/jit/flowgraph.cpp
Simple merge

diff --cc src/coreclr/src/jit/gentree.cpp
Simple merge

diff --cc src/coreclr/src/jit/gentree.h
Simple merge

diff --cc src/coreclr/src/jit/importer.cpp
Simple merge

diff --cc src/coreclr/src/jit/lclvars.cpp
Simple merge

diff --cc src/coreclr/src/jit/lower.cpp
Simple merge

diff --cc src/coreclr/src/jit/lowerxarch.cpp
Simple merge

diff --cc src/coreclr/src/jit/morph.cpp
Simple merge

diff --cc src/coreclr/src/jit/rationalize.cpp
Simple merge

diff --cc src/coreclr/src/jit/valuenum.cpp
Simple merge