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README.md

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+Hello world, in Linux, for multiple architectures
+=================================================
+
+Architectures
+=============
+
+* x86-32
+* amd64 (aka x86-64)
+* arm7l (32 bit arm)
+* aarch64 (64 bit arm)
+* riscv64 (RISC-V 64 bit)
+
+
+Notes
+=====
+
+I wanted to create a "real" sample of assembly in different architectures. By
+"real", the program should do some actual work, and interface with the operating
+system. Real programs typically have "functions", so our program should do that
+as well.
+
+This repository serves to provide examples of assembly language implementations
+of a hello world program. The program prints a hard coded string, then exits.
+The exit code is calculated based on the square of the arguments (think argc
+in C). The argument count is inserted into the stack by Linux, and is described
+well at [LWN](https://lwn.net/Articles/631631/). Doing this will use a function
+to square our argc and interface with Linux to print our string and set the
+correct exit code.
+
+Linkers typically set the entry point of the program based on a symbol named
+"\_start". In C, the \_start entry point will perform some logistical work
+required by the compiler, then transfer control to main. Here in assembly,
+we can start work directly.
+
+I have tried to fully annotate each architecture's assembly with suitable
+references. I have also left some optimizations out. Transferring function
+arguments to memory only to turn around and load them into registers makes
+little sense; however, this is a useful pattern, so I have not optimized these
+patterns.
+