Also disables generation of MutateOpcode. It's almost never used in
combiners anyway.
If we really want to use it, it needs to be investigated & properly
fixed (see TODO)
Fixes#70780
The inference is trivial and leverages the MCOI OperandTypes encoded in
CodeGenInstructions to infer types across patterns in a CombineRule.
It's thus very limited and only supports CodeGenInstructions (but that's the
main use case so it's fine).
We only try to infer untyped operands in apply patterns when they're
temp reg defs, or immediates. Inference always outputs a `GITypeOf<$x>` where
$x is a named operand from a match pattern.
This allows us to drop the `GITypeOf` in most cases without any errors.
Adds a new feature to MIR patterns: builtin instructions.
They offer some additional capabilities that currently cannot be expressed without falling back to C++ code.
There are two builtins added with this patch, but more can be added later as new needs arise:
- GIReplaceReg
- GIEraseRoot
Depends on D158714, D158713
Reviewed By: arsenm, aemerson
Differential Revision: https://reviews.llvm.org/D158975
Now that the old backend is gone, clean-up a few things that no longer make sense and tidy up the file a bit.
Depends on D158710
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D158714
The MatchTable-based GlobalISel Combiner backend is the new default. There are no in-tree users left of the old backend.
- Removed implementation of old MatchDAG-based Combiner, including tests, the backend itself and all supporting code.
- Renamed MatchTable backend to `GlobalISelCombinerEmitter.cpp` + removed "-matchtable" from its CL option.
- no need to have a verbose name as it's the only backend left now.
Reviewed By: aemerson
Differential Revision: https://reviews.llvm.org/D158710
