When either one of the operands is all ones in high or low parts, splitting these opens up other opportunities for combines. One of two new instructions will either be removed or become a simple copy.
- rename `GISelKnownBits` to `GISelValueTracking` to analyze more than just `KnownBits` in the future
(This replaces #121740. Sorry for wasting your time.) This is a follow-up to a previous commit (ee7ca0d) which eliminated several "TODO: make CombinerHelper methods const" remarks. As promised in that ealier commit, this change completes the set by also making the methods of AMDGPUCombinerHelper const so that the Helper member of AMDGPUPreLegalizerCombinerImpl can be const rather than explicitly mutable.
This combine pattern perform the below transformation. fmul x, select(y, A, B) -> fldexp (x, select i32 (y, a, b)) fmul x, select(y, -A, -B) -> fldexp ((fneg x), select i32 (y, a, b)) where, A=2^a & B=2^b ; a and b are integers. It is a follow-up PR to implement the above combine for globalIsel, as the corresponding DAG combine has been done for SelectionDAG Isel (#111109)
Co-authored-by: Stanislav Mekhanoshin <Stanislav.Mekhanoshin@amd.com>
The set of handled intrinsics for fneg combines aren't convergent. The only case we might want to handle is mov_dpp.
Introduced the convergent equivalent of the existing G_INTRINSIC opcodes: - G_INTRINSIC_CONVERGENT - G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS Out of the targets that currently have some support for GlobalISel, the patch assumes that the convergent intrinsics only relevant to SPIRV and AMDGPU. Reviewed By: arsenm Differential Revision: https://reviews.llvm.org/D154766
Some opcodes in generic MIR represent calls to intrinsics, where the intrinsic ID is the first non-def operand to the instruction. These are now represented as a subclass of GenericMachineInstr, and the method MachineInstr::getIntrinsicID() is now moved to this subclass GIntrinsic. Some target-defined instructions behave like GMIR intrinsics, and have an Intrinsic::ID operand. But they should not be recognized as generic intrinsics, and should not use GIntrinsic::getIntrinsicID(). Separated these out by introducing a new AMDGPU::getIntrinsicID(). Reviewed By: arsenm, Pierre-vh Differential Revision: https://reviews.llvm.org/D155556 This restores commit baa3386edb11a2f9bcadda8cf58d56f3707c39fa. Originally reverted in d0f7850b01cf17e50a4f4b00e3b84dded94df6b8.