Google removes SIMD.js support from Chromium

Re:Google removes SIMD.js support from Chromium by brigade on Sunday June 04, 2017 @05:50AM (#14480575)

And for a counterpoint that it's still the case that compilers can produce horrible codegen from intrinsics in 2017, this entire thread: http://www.realworldtech.com/forum/?threadid=166719

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Re:Google removes SIMD.js support from Chromium by zvrba on Sunday June 04, 2017 @06:08AM (#14480637)

Oh. He used 14 registers to manually unroll the inner loop. IME, on modern architectures, manual unrolling doesn't win you anything (benchmarked on, among other things, the above-mentioned dotproduct). I wouldn't be surprised if he got close to optimal code by just NOT manually unrolling. Fewer registers used, compiler less confused.

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Re:Google removes SIMD.js support from Chromium by rurban on Sunday June 04, 2017 @06:14AM (#14480660)

I thought M.Matz recently fixed the register allocation mess, but apparently only the most egregious parts.

See the old official pre-Matz gcc statements on the mess https://gcc.gnu.org/wiki/RegisterAllocation

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