pizlonator

Here's a much more complete description of how I do SSA, beyond just how I do Phis.

This describes how I do SSA form, which avoids the need to have any coupling between CFG data structures and SSA data structures.

Let's first define a syntax for SSA and some terminology. Here's an example SSA node:

A = Add(B, C)

In reality, this will be a single object in your in-memory representation, and the names are really addresses of those objects. So, this node has an "implicit variable" called A; it's the variable that is implicitly assigned to when you execute the node. If you then do:

no-defun-allowed

Don’t Build Your Own Lisp

I feel somewhat pressed to give a negative review of this book. This comes from someone who has worked on various Lisp implementations, and written some amount of C, but that isn’t an excuse to be overly harsh. This book, however, does not provide many nice things to say, and plenty of un-nice things. My apologies in advance.

First off: God help you if you are going to write your first interpreter in C of all things. No one I know thinks it’s a good idea to start

nikodemus

;;;; In response to:
;;;;
;;;;    http://www.reddit.com/r/lisp/comments/3710zq/directed_procrastination_backtracking_with_the/
;;;;    http://directed-procrastination.blogspot.se/2011/05/backtracking-with-common-lisp-condition.html
;;;;
;;;; Demonstrating why one should not use conditions for this kind of stuff,
;;;; instead using the dynamic binding and unwinding facilities on which the
;;;; condition system is built. The author's backtracking system doesn't compare
;;;; badly to Screamer because his is simple: it compares badly because using
;;;; conditions is a bad match for the task.