Avoid varargs in socket syscall layer. NFC#27153
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Passing a small number of integer arguments may be cheaper than marshalling varargs on wasm64.
This is an automatic change generated by tools/maint/rebaseline_tests.py. The following (1) test expectation files were updated by running the tests with `--rebaseline`: ``` codesize/test_codesize_hello_dylink_all.json: 855843 => 855818 [-25 bytes / -0.00%] Average change: -0.00% (-0.00% - -0.00%) ```
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It looks like we still have explicit usage of varargs in 4 syscalls: ioctl fcntl64 fstatfs64 openat. Presumably removing that is more complex? But if we did then we could remove the whole syscallGetVararg thing? |
| return 0; | ||
| }, | ||
| __syscall_getpeername__deps: ['$getSocketFromFD', '$writeSockaddr', '$DNS'], | ||
| __syscall_getpeername: (fd, addr, addrlen, d1, d2, d3) => { |
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The man page calls this addrlen. Is there some reason to change it?
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I was trying to sync these syscalls argument names with their corresponding callers:
emscripten/system/lib/libc/musl/src/network/getpeername.c
Lines 4 to 7 in 8484a7b
| "$__syscall_munmap", | ||
| "$__syscall_prlimit64", | ||
| "$__syscall_recvmmsg", | ||
| "$__syscall_sendmmsg", |
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I wonder why this change effects this list?
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Probably due to identical code folding (ICF). At least it saves 25 bytes. :)
| "$__syscall_munmap", | ||
| "$__syscall_prlimit64", | ||
| "$__syscall_recvmmsg", | ||
| "$__syscall_sendmmsg", |
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Oh I think maybe some optimization phase was doing duplicate function merging before on this stub, but its no longer identical maybe.
Indeed, it's probably too complex. And unlike the socket syscalls, these varargs are actually used and cannot be turned into constants (afaik). |
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Passing a small number of integer arguments may be cheaper than
marshalling varargs on wasm64.
Split out from #19559.