Hi all, Upon some further inspection I realised I had misunderstood some intricacies of the extending loads of the RCPC feature. This patch fixes up the recent GCC support accordingly. In particular: * The sign-extending forms are a form of LDAPURS* and are actually part of FEAT_RCPC2 that is enabled with Armv8.4-a rather than the base Armv8.3-a FEAT_RCPC. The patch introduces a TARGET_RCPC2 macro and gates this combine pattern accordingly. * The assembly output for the zero-extending LDAPR instruction should always use %w formatting for its destination register.
The testcase is split into zero-extending and sign-extending parts since they require different architecture pragmas. It's also straightforward to add the rest of the FEAT_RCPC2 codegen (with immediate offset addressing modes) but that can be done as a separate patch. Apologies for not catching this sooner, but it hasn't been in trunk long, so no harm done. Bootstrapped and tested on aarch64-none-linux-gnu. Pushing to trunk. Thanks, Kyrill gcc/ChangeLog: * config/aarch64/aarch64.h (TARGET_RCPC2): Define. * config/aarch64/atomics.md (*aarch64_atomic_load<ALLX:mode>_rcpc_zext): Adjust output template. (*aarch64_atomic_load<ALLX:mode>_rcpc_sex): Guard on TARGET_RCPC2. Adjust output template. * config/aarch64/iterators.md (w_sz): New mode attr. gcc/testsuite/ChangeLog: * gcc.target/aarch64/ldapr-ext.c: Rename to... * gcc.target/aarch64/ldapr-zext.c: ... This. Fix expected assembly. * gcc.target/aarch64/ldapr-sext.c: New test.
ldapr-fix.patch
Description: ldapr-fix.patch