Implement first D-specific optimization pass: -simplify-drtcalls. It uses the machinery of the standard -simplify-libcalls pass, but optimizes calls to the D runtime instead of calls to C libraries. At the moment, these optimizations are implemented by this pass: - Avoid the runtime call for `arr.length = newlen` if it can determine that the new length isn't longer than the old one. - Ditto for `cast(T[]) arr` if it will clearly always succeed. (e.g. if the length of the original array is zero, or if the old element size is a multiple of the new element size)

#!/bin/sh

g++ llvm-ext.cpp -c `llvm-config --cxxflags`
g++ llvm-opt.cpp -c `llvm-config --cxxflags`
g++ llvm-typemonitor.cpp -c `llvm-config --cxxflags`

rm -f libllvm-c-ext.a
ar rc libllvm-c-ext.a llvm-ext.o llvm-opt.o llvm-typemonitor.o
ranlib libllvm-c-ext.a