search for: constantfoldingmirbuilder

Displaying 2 results from an estimated 2 matches for "constantfoldingmirbuilder".

2019 May 20
2
GlobalISel: Very limited pattern matching?
...t the moment, it's fairly common to have some C++ instruction selection or additional patterns (usually C++ as many of the targets pre-date the SelectionDAG importer) filling in the gaps in the imported rules. There's fairly limited support for constant folding at the moment. There's a ConstantFoldingMIRBuilder which folds when instructions are created and a CSEMIRBuilder which also constant folds at the same time as CSE'ing. I just had a quick look at them and it seems we only constant fold binary operations. I just asked Aditya (who added it) about this and the main issue is identifying that a new G...
2019 May 20
3
GlobalISel: Very limited pattern matching?
Hi all, I'm trying to get GlobalISel up and running on an off-tree architecture and am thinking I must be doing something wrong, given by how few things actually work. Namely, any ImmLeaf pattern will fail to match if there is a (TRUNC/ZEXT/SEXT) applied to the constant operand, all of which are commonly created through Legalization. This is due to G_CONSTANT being explicitly looked for by