This is identical for each target. So, move the initialization to
common code. Move the variable itself out of tcg_ctx and name it
cpu_env to minimize changes within targets.
This also means we can remove tcg_global_reg_new_{ptr,i32,i64},
since there are no longer global-register temps created by targets.
Backports commit 1c2adb958fc07e5b3e81ed21b801c04a15f41f4f from qemu
Use dup to convert a non-constant scalar to a third vector.
Add addition, multiplication, and logical operations with an immediate.
Add addition, subtraction, multiplication, and logical operations with
a non-constant scalar. Allow for the front-end to build operations in
which the scalar operand comes first.
Backports commit 22fc3527034678489ec554e82fd52f8a7f05418e from qemu
No vector ops as yet. SSE only has direct support for 8- and 16-bit
saturation; handling 32- and 64-bit saturation is much more expensive.
Backports commit f49b12c6e6a75a5bd109bcbbda072b24e5fb8dfd from qemu
Opcodes are added for scalar and vector shifts, but considering the
varied semantics of these do not expose them to the front ends. Do
go ahead and provide them in case they are needed for backend expansion.
Backports commit d0ec97967f940bbc11dced83422b39c224127f1e from qemu
