Commit Graph

2 Commits

Author SHA1 Message Date
Sam Parker 39af8a3a3b [DAGCombine][ARM] Enable extending masked loads
Add generic DAG combine for extending masked loads.

Allow us to generate sext/zext masked loads which can access v4i8,
v8i8 and v4i16 memory to produce v4i32, v8i16 and v4i32 respectively.

Differential Revision: https://reviews.llvm.org/D68337

llvm-svn: 375085
2019-10-17 07:55:55 +00:00
David Green b325c05732 [ARM] Masked loads and stores
Masked loads and store fit naturally with MVE, the instructions being easily
predicated. This adds lowering for the simple cases of masked loads and stores.
It does not yet deal with widening/narrowing or pre/post inc, and so is
currently behind an option.

The llvm masked load intrinsic will accept a "passthru" value, dictating the
values used for the zero masked lanes. In MVE the instructions write 0 to the
zero predicated lanes, so we need to match a passthru that isn't 0 (or undef)
with a select instruction to pull in the correct data after the load.

Differential Revision: https://reviews.llvm.org/D67186

llvm-svn: 371932
2019-09-15 14:14:47 +00:00