[llvm] [InstCombine] Extend folding of aggregate construction to cases when source aggregates are partially available (PR #100828)

[Yingwei Zheng via llvm-commits]

dtcxzyw wrote:

> @dtcxzyw could you help to explain these numbers? Execution time? File size? Number of llvm IR instructions?
> 
> ```
> Top 5 improvements:
>   minetest/s_client.cpp.ll 300581269 294367598 -2.07%
>   abseil-cpp/kernel_timeout_test.cc.ll 1973629781 1937840415 -1.81%
>   cmake/cmFindBase.cxx.ll 1913629020 1891008778 -1.18%
>   assimp/IFCReaderGen2_2x3.cpp.ll 3046110312 3017099134 -0.95%
>   darktable/lut3dgmic.cpp.ll 236183674 234289794 -0.80%
> Top 5 regressions:
>   minetest/test_connection.cpp.ll 682795465 698591227 +2.31%
>   cmake/cmQtAutoMocUic.cxx.ll 8264379610 8383878253 +1.45%
>   tokio-rs/132n8ebvfaa2dg8b.ll 82150296 82583502 +0.53%
>   tokio-rs/40sgumesnmyyffj3.ll 67652318 67979824 +0.48%
>   spike/f128_rem.ll 123368228 123914940 +0.44%
> 
> Overall: 0.01762297%
> ```
> 
> I can guess out the numbers in other two parts, the llvm stats result and the changed lines in diff result.

It is the number of instructions executed by `opt -O3`.



https://github.com/llvm/llvm-project/pull/100828