[AArch64] Replace expensive move from wzr by two moves via floating point immediate. #11962
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…oint immediate (llvm#146538) We've noticed that inserting 0 into a known vector lane is implemented via a move from wzr, i.e., moving between register banks. We think it will be cheaper (and have seen improvements on our benchmarks) to materialize 0 into a floating point register and insert from there. PR: llvm#146538 (cherry picked from commit e333d60)
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| @swift-ci please test llvm |
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| @swift-ci please test windows platform |
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| @swift-ci please test windows platform |
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We've noticed that inserting 0 into a known vector lane is implemented via a move from wzr, i.e., moving between register banks. We think it will be cheaper (and have seen improvements on our benchmarks) to materialize 0 into a floating point register and insert from there.
PR: llvm#146538 (cherry picked from commit e333d60)