================
@@ -490,6 +490,35 @@ void tools::AddLinkerInputs(const ToolChain &TC, const
InputInfoList &Inputs,
else
A.renderAsInput(Args, CmdArgs);
}
+ if (const Arg *A = Args.getLastArg(options::OPT_fveclib)) {
+ const llvm::Triple &Triple = TC.getTriple();
+ StringRef V = A->getValue();
+ if (V == "ArmPL" && (Triple.isOSLinux() || Triple.isOSDarwin())) {
+ // To support -fveclib=ArmPL we need to link against libamath.
+ // Some of the libamath functions depend on libm, at the same time,
+ // libamath exports its own implementation of some of the libm
+ // functions. Since here we are interested only in the subset of
+ // libamath functions that is covered by the veclib mappings,
+ // we need to do the following:
+ //
+ // 1. On Linux, link only when actually needed.
+ //
+ // 2. Prefer libm functions over libamath.
+ //
+ // 3. Link against libm to resolve libamath dependencies.
+ //
+ if (Triple.isOSLinux()) {
+ CmdArgs.push_back(Args.MakeArgString("--push-state"));
+ CmdArgs.push_back(Args.MakeArgString("--as-needed"));
+ }
+ CmdArgs.push_back(Args.MakeArgString("-lm"));
----------------
pawosm-arm wrote:
> If "It's a matter of prioritizing system-libm over libamath which contains
> faster (and potentially less accurate) implementations of some of the libm
> functions.", the comment above doesn't seem to mention this.
>
Now it mentions.
> However, I am confused. Why cannot these duplicate symbols be removed from
> libamath so that the compiler driver doesn't have to play with circular -lm
> and -lamath dependency?
>
> If the reason is that we want to support both old libm and new libm where
> libm contains faster implementations also in libamath, I expect this
> reasoning to be covered.
This is purely historical reason. Libamath was meant to be libm replacement,
being veclib provider for fveclib=ArmPL just one more role of this lib. The
user still needs to be able to specify `-lamath` to be able to choose those
less accurate faster functions, and I've made this covered by now added extra
checks in the test cases.
https://github.com/llvm/llvm-project/pull/116432
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
