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ClangBuiltLinux / tc-build

A set of scripts to build LLVM and binutils
Apache License 2.0
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Toolchain from kernel.org shipped without polly #281

Closed wctrl closed 1 week ago

wctrl commented 1 week ago

Is this how it's supposed to be? The build script says that polly is already selected by default

Extra info: version: ClangBuiltLinux clang version 19.1.2 Check polly: clang -mllvm --help init/main.c | grep polly (will fail without any input file)

nathanchance commented 1 week ago

The kernel.org toolchains are built using tc-build but I used a different set of projects: https://github.com/nathanchance/env/blob/879b5ed9f156adb2f2bae115e55f2d5058a08f36/python/pgo-llvm-builder/build.py#L174-L178

While it was not entirely intentional to omit polly from that list, I am not really inclined to add it because there has been little empirical evidence that the Linux kernel benefits from polyhedral optimizations. There was a patch submitted upstream with some numbers but they did not really seem convincing to me and there was nobody else who stepped up to help test and benchmark.

wctrl commented 1 week ago

I see, thanks!