Hello Jeff: On 20/04/23 3:29 am, Jeff Law wrote: > > > On 4/19/23 12:03, Ajit Agarwal wrote: >> Hello All: >> >> This is patch-4 to improve ree pass for rs6000 target. >> Use ABI interfaces support. >> >> Bootstrapped and regtested on powerpc64-linux-gnu. >> >> Thanks & Regards >> Ajit >> >> ree: Improve ree pass for rs6000 target. >> >> For rs6000 target we see redundant zero and sign >> extension and done to improve ree pass to eliminate >> such redundant zero and sign extension. Support of >> ABI interfaces. >> >> 2023-04-19 Ajit Kumar Agarwal <aagar...@linux.ibm.com> >> >> gcc/ChangeLog: >> >> * ree.cc (combline_reaching_defs): Add zero_extend and sign_extend. >> Add FUNCTION_ARG_REGNO_P abi interfaces calls and >> FUNCTION_VALUE_REGNO_P support. >> (add_removable_extension): Add FUNCTION_ARG_REGNO_P abi >> interface calls. >> >> gcc/testsuite/ChangeLog: >> >> * g++.target/powerpc/zext-elim-3.C > So my general comment on this code is we need to expose properties of the ABI > so they can be queried. ie, just because you found that a REGNO happens to > be a function argument doesn't mean you know anything about its extension > status. We need a way to describe the extension property of the ABI. > Ideally there'll be something pre-existing that we can query, but I'm not > sure that's the case. > > The overarching point is what you're doing is highly dependent on the precise > semantics of the ABI. But nowhere do you ask the question "does the ABI > mandate a particular sign/zero extension state for this argument?" So it's > just wrong as-written as far as I can tell. >
I have submitted new version of the patch which incorporates the above. Please review and let me know your feedback. Thanks & Regards Ajit > Jeff >
