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+# Soft-FP sh3eb port of OpenLibm
+
+This is a fork of [OpenLibm](https://github.com/JuliaMath/openlibm) with
+support for the sh3eb architecture, intended for add-in programming on fx-9860G
+and fx-CG 50.
+
+## Building
+
+You will need a GCC toolchain built with `--target=sh3eb-elf`, such as the
+`sh-elf-gcc` commonly used on Planète Casio.
+
+First locate the compiler's install directory. This is normally the
+`lib/gcc/sh3eb-elf/<version>/` folder inside the install path of the compiler.
+
+```
+% PREFIX=$(sh-elf-gcc --print-search-dirs | grep install | sed 's/install: //')
+```
+
+You can then build and install the static `libopenlibm.a` archive and the headers.
+
+```
+% make USEGCC=1 TOOLPREFIX=sh-elf- libdir="$PREFIX" includedir="$PREFIX/include" install-static install-headers
+```
+
+## Using in a program
+
+Simply link with `-lopenlibm` as you would do with `-lm`.
+
+## README and Licensing
+
+See the original README file in README-OpenLibm.md. OpenLibm contains code
+covered by various licenses, see LICENSE.md.