[Bug libstdc++/115454] New: std::experimental::find_last_set is buggy on x86-64-v4

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115454 Bug ID: 115454 Summary: std::experimental::find_last_set is buggy on x86-64-v4 Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3

[Bug tree-optimization/114966] fails to optimize avx2 in-register permute written with std::experimental::simd

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114966 --- Comment #1 from Imple Lee --- This is probably a regression. GCC 13.2 can generate optimal code. See https://godbolt.org/z/4n8ovr7jr .

[Bug tree-optimization/114908] fails to optimize avx2 in-register permute written with std::experimental::simd

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114908 --- Comment #8 from Imple Lee --- I tried another way to permute the register. Although GCC does generate simd instructions, the generated code is sub-optimal. I opened PR114966 for that.

[Bug tree-optimization/114966] New: fails to optimize avx2 in-register permute written with std::experimental::simd

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114966 Bug ID: 114966 Summary: fails to optimize avx2 in-register permute written with std::experimental::simd Product: gcc Version: 14.0 Status: UNCONFIRMED

[Bug target/114908] New: fails to optimize avx2 in-register permute written with std::experimental::simd

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114908 Bug ID: 114908 Summary: fails to optimize avx2 in-register permute written with std::experimental::simd Product: gcc Version: 14.0 Status: UNCONFIRMED

[Bug libstdc++/114417] std::experimental::simd is not a POD (by ABI definitions) and is always passed by reference instead of by value

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114417 --- Comment #11 from Imple Lee --- > What you want to use instead is std::experimental::simd_abi::deduce_t. > That'll give you a not-fixed_size ABI if one exists. And those will likely be > passed via registers (as long as the psABI allows).

[Bug libstdc++/114417] std::experimental::simd is not a POD (by ABI definitions) and is always passed by reference instead of by value

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114417 --- Comment #7 from Imple Lee --- I tried to dig into the source code and it seems like it was designed to be "passed via the stack". Not sure whether this was specified by the specification (did not find relevant requirements, but I am not

[Bug target/114417] simd parameters are passed by memory on x64 , not using the available sse registers

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114417 --- Comment #3 from Imple Lee --- Oh, I didn't make it clear. I am describing libstdc++'s std::experimental::simd class.

[Bug target/114417] simd parameters are passed by memory on x64 , not using the available sse registers

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114417 --- Comment #2 from Imple Lee --- (In reply to Andrew Pinski from comment #1) > I doubt this can change since this is the abi gcc decided on a long time ago. If we implement the simd class as a wrapper around a vector, the parameter can still

[Bug libstdc++/114417] New: simd parameters are passed by memory on x64 , not using the available sse registers

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114417 Bug ID: 114417 Summary: simd parameters are passed by memory on x64 , not using the available sse registers Product: gcc Version: unknown Status: UNCONFIRMED