Miscellaneous improvements

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 13 insertions, 0 deletions

diff --git a/config.mk b/config.mk
index 1cc7dcb..e0b7aa7 100644
--- a/config.mk
+++ b/config.mk
@@ -23,6 +23,19 @@ LDFLAGS  =
 # which returns the index, plus 1, of the least significant set bit
 # or 0 for 0, you can add -DHAVE_BUILTIN_FFSLL to CPPFLAGS; if you
 # are using GCC>=3.4 or clang>=5, this is added automatically.
+# Additionally, you can add -DUSE_INTERPOLATION_SEARCH to CPPFLAGS
+# if you want the library to use interpolation search instead of
+# binary search, this is probably a bad idea on platforms that do
+# not support division natively, even on amd64, it does not seem to
+# make any difference at the moment. If you add -DUSE_INTERPOLATION_SEARCH,
+# you may also add `-DINTERPOLATION_SEARCH_FLOAT=long double` (default),
+# `-DINTERPOLATION_SEARCH_FLOAT=double` or `-DINTERPOLATION_SEARCH_FLOAT=float`
+# to specify which floating point type interpolation search should use
+# if it cannot used integers; which option is best depends on the
+# platform, as some platforms can work natively with any of the types
+# and those `float` is most performant, and other platforms (such as
+# i386) can only work natively with a specific type (`long double` in
+# the case of i386) and thus performs best with that type.
 
 DOWNLOAD = curl --