Extends avo to support most AVX-512 instruction sets.
The instruction type is extended to support suffixes. The K family of opmask
registers is added to the register package, and the operand package is updated
to support the new operand types. Move instruction deduction in `Load` and
`Store` is extended to support KMOV* and VMOV* forms.
Internal code generation packages were overhauled. Instruction database loading
required various messy changes to account for the additional complexities of the
AVX-512 instruction sets. The internal/api package was added to introduce a
separation between instruction forms in the database, and the functions avo
provides to create them. This was required since with instruction suffixes there
is no longer a one-to-one mapping between instruction constructors and opcodes.
AVX-512 bloated generated source code size substantially, initially increasing
compilation and CI test times to an unacceptable level. Two changes were made to
address this:
1. Instruction constructors in the `x86` package moved to an optab-based
approach. This compiles substantially faster than the verbose code
generation we had before.
2. The most verbose code-generated tests are moved under build tags and
limited to a stress test mode. Stress test builds are run on
schedule but not in regular CI.
An example of AVX-512 accelerated 16-lane MD5 is provided to demonstrate and
test the new functionality.
Updates #20#163#229
Co-authored-by: Vaughn Iverson <vsivsi@yahoo.com>
Currently `avo` uses `BP` as a standard general-purpose register. However, `BP` is used for the frame pointer and should be callee-save. Under some circumstances, the Go assembler will do this automatically, but not always. At the moment `avo` can produce code that clobbers the `BP` register. Since Go 1.16 this code will also fail a new `go vet` check.
This PR provides a (currently sub-optimal) fix for the issue. It introduces an `EnsureBasePointerCalleeSaved` pass which will check if the base pointer is written to by a function, and if so will artificially ensure that the function has a non-zero frame size. This will trigger the Go assembler to automatically save and restore the BP register.
In addition, we update the `asmdecl` tool to `asmvet`, which includes the `framepointer` vet check.
Updates #156
Issue #100 demonstrated that register allocation for aliased registers is
fundamentally broken. The root of the issue is that currently accesses to the
same virtual register with different masks are treated as different registers.
This PR takes a different approach:
* Liveness analysis is masked: we now properly consider which parts of a register are live
* Register allocation produces a mapping from virtual to physical ID, and aliasing is applied later
In addition, a new pass ZeroExtend32BitOutputs accounts for the fact that 32-bit writes in 64-bit mode should actually be treated as 64-bit writes (the result is zero-extended).
Closes#100
