Correctly round double precision sqrt #256
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As discussed in JuliaLang/julia#43786, openlibm's sqrt function is incorrectly rounded for i387. IEEE requires correct rounding for these functions and LLVM relies on it. Fix that by setting the precision in the FPU control word (see e.g. e_ceil.S for similar FPU modifications).
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As discussed in JuliaLang/julia#43786, openlibm's sqrt function is incorrectly rounded for i387. IEEE requires correct rounding for these functions and LLVM relies on it. Fix that by setting the precision in the FPU control word (see e.g. e_ceil.S for similar FPU modifications).
Similar changes are not required for single precision because it does not suffer from the double rounding issue.