grok_bin_oct_hex: Minor improvements to precision, speed #23975
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tonycoz
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Dec 1, 2025
Underscores in numbers are much less common than digits, and its unlikely that this iteration of the loop through all the digits will still have a running total of 0.
grok_bin_oct_hex: Move comments And reflow. This is in preparation for the next commit.
We can compute outside the loop the exact value at which the next iteration wil overflow, saving some operations
This replaces a floating multiply each loop iteration with an integer increment, plus after the loop completes, a call to ldexp() or pow(). Most of the floating multiplies are done on integral values, so not much precision is lost, but this gets it down to just one precision-losing operation.
khwilliamson
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These commits
ldexpOne question I have is can I just assume that
Perl_ldexpexists and not have a fallback toPerl_pow? I think C99 requires all versions we need to be available, but it's not clear to me thatperl.hguarantees one.