On 7/21/2022 3:05 AM, Richard Biener via Gcc-patches wrote:
The following enhances DSE to handle LEN_STORE (optimally) and
MASK_STORE (conservatively).
Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
Kewen is testing on powerpc. Handling MASK_STORE_LANES in
a similar way to MASK_STORE is probably possible but I couldn't
figure a way to generate one for testing. STORE_LANES is
probably handled already since it's ECF_CONST.
PR tree-optimization/106365
* tree-ssa-dse.cc (initialize_ao_ref_for_dse): Handle
LEN_STORE, add mode to initialize a may-def and handle
MASK_STORE that way.
(dse_optimize_stmt): Query may-defs. Handle internal
functions LEN_STORE and MASK_STORE similar to how
we handle memory builtins but without byte tracking.
LGTM. Obviously if you can massage the PR into a testcase, it's even
better :-)
jeff
