Messages in this thread | | | Date | Tue, 30 Jun 2020 22:20:59 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH 18/18] arm64: lto: Strengthen READ_ONCE() to acquire when CLANG_LTO=y |
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On Tue, Jun 30, 2020 at 09:47:30PM +0200, Marco Elver wrote: > I do wonder, though, if there is some way to make the compiler do > something better for us. Clearly, implementing real > memory_order_consume hasn't worked out until today. But maybe the > compiler could promote dependent loads to acquires if it recognizes it > lost dependencies during optimizations. Just thinking out loud, it > probably still has some weird corner case that will break. ;-)
I'd be very hesitant to let the compiler upgrade the ordering for us, specifically because we're not using C11 crud and are using a lot of inline asm.
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