[llvm] Use (de)interleaving intrinsics for fixed-length vectors (PR #202583)

[via llvm-commits]

github-actions[bot] wrote:

test-suite diff from febf50748effc5fb381ad479cf129f1ebcdc4bec...1f142ac5788619fdd8d9063b68f3705c2f5220c2: https://github.com/llvm/llvm-project/actions/runs/31468064186/artifacts/9094427438

Statistics: https://github.com/llvm/llvm-project/actions/runs/31468064186/artifacts/9094428103

## riscv64-linux-gnu `-march=rva23u64 -O3`
| ('Program', '')    |   ('size..text', 'base') |   ('size..text', 'head') |   ('size..text', 'diff') |
|:-------------------|-------------------------:|-------------------------:|-------------------------:|
| Geomean difference |                      nan |                      nan |                        0 |
## aarch64-linux-gnu `-march=armv9-a -O3`
| ('Program', '')                             |   ('size..text', 'base') |   ('size..text', 'head') |   ('size..text', 'diff') |
|:--------------------------------------------|-------------------------:|-------------------------:|-------------------------:|
| test-suite...eProcessing/Dither/Dither.test |                   229416 |                   229428 |              5.23067e-05 |
| Geomean difference                          |                      nan |                      nan |             -0.000186546 |
## x86_64-linux-gnu `-march=x86-64-v3 -O3`
| ('Program', '')                             |   ('size..text', 'base') |   ('size..text', 'head') |   ('size..text', 'diff') |
|:--------------------------------------------|-------------------------:|-------------------------:|-------------------------:|
| MultiSourc...rks/BitBench/uudecode/uudecode |                     1695 |                     1855 |              0.0943953   |
| MultiSourc...rks/BitBench/uuencode/uuencode |                     2841 |                     3001 |              0.0563182   |
| MultiSourc...arks/DOE-ProxyApps-C/CoMD/CoMD |                    41049 |                    41353 |              0.00740578  |
| SingleSour...enchmarks/CoyoteBench/fftbench |                     9837 |                     9885 |              0.00487954  |
| MultiSourc...e/Benchmarks/MallocBench/gs/gs |                   158605 |                   159133 |              0.00332902  |
| MultiSource/Benchmarks/PAQ8p/paq8p          |                   105104 |                   105376 |              0.00258791  |
| MultiSourc...-ProxyApps-C++/PENNANT/PENNANT |                   122989 |                   123165 |              0.00143102  |
| MultiSourc...nchmarks/tramp3d-v4/tramp3d-v4 |                   847593 |                   848377 |              0.000924972 |
| MultiSourc.../Applications/JM/ldecod/ldecod |                   304950 |                   305174 |              0.000734547 |
| MultiSource/Applications/hbd/hbd            |                    34063 |                    34079 |              0.000469718 |
| MultiSourc...enchmarks/mafft/pairlocalalign |                   535698 |                   535906 |              0.000388278 |
| MultiSourc...Benchmarks/7zip/7zip-benchmark |                   965146 |                   965466 |              0.000331556 |
| Bitcode/Be...ral_grid/halide_bilateral_grid |                    56656 |                    56672 |              0.000282406 |
| MultiSourc...ks/ASCI_Purple/SMG2000/smg2000 |                   263030 |                   263062 |              0.000121659 |
| MultiSource/Applications/oggenc/oggenc      |                   306254 |                   306270 |              5.22442e-05 |
| Geomean difference                          |                      nan |                      nan |             -0.00028261  |


https://github.com/llvm/llvm-project/pull/202583