Finalize EP14

dev.org

@@ -103,7 +103,8 @@ on ADF
 - [[https://blog.yossarian.net/2021/07/19/LLVM-internals-part-1-bitcode-format][LLVM Internals]]
 *** TableGen
 - [[https://llvm.org/docs/TableGen/BackGuide.html#creating-a-new-backend][Create a backend]]
-
+** Useful courses
+-  https://www.cs.cornell.edu/courses/cs6120/2020fa/lesson/
 * Considerations
 ** Hashmaps
 *** DOS attack

docs/videos.org

@@ -562,7 +562,8 @@ and tries to =resolve= *undefined* symbols
 ** Let's look at some code
 ** Resources:
 - [[https://lwn.net/Articles/276782/][20 part linker essay]]
-* Episode 13 - Source Managers
+* DONE Episode 13 - Source Managers
+CLOSED: [2021-12-18 Sat 11:17]
 ** FAQ:
 - What tools are you using?
 
@@ -582,3 +583,134 @@ I didn't show it in action
   - ...
 
 - LLVM provides a =SourceMgr= class that we're not using it
+* Episode 14 - JIT Basics
+** Updates:
+- Lost my data :_(
+- Fixed some compatibility issues
+- New video series on *How to build an editor with Emacs Lisp*
+
+** What is Just In Time Compilation?
+- Compiling at "runtime" (air quote)
+  Or it might be better to say, "on demand compilation"
+- Usually in interpreters and Runtimes
+
+#+NAME: ep-14-jit-1
+#+BEGIN_SRC graphviz-dot :file /tmp/jit.svg :cmdline -Kdot -Tsvg
+  digraph {
+    graph [bgcolor=transparent]
+    node [color=gray80 shape="box"]
+    edge [color=gray80]
+    rankdir = "LR"
+
+    a[label="Some kind of input code"]
+    b[label="JIT"]
+    c[label="Some sort of target code"]
+    d[label="Execute the result"]
+    a -> b -> c -> d
+  }
+#+END_SRC
+
+#+RESULTS: ep-14-jit-1
+[[file:/tmp/jit.svg]]
+
+
+
+#+NAME: ep-14-jit-2
+#+BEGIN_SRC graphviz-dot :file /tmp/jit-2.svg :cmdline -Kdot -Tsvg
+
+  digraph G {
+        graph [bgcolor=transparent]
+        node [color=gray80 shape="box"]
+        edge [color=gray80]
+        rankdir = "LR"
+
+        a[label="Source code"]
+        b[label="Parser"]
+        c[label="Semantic Analyzer"]
+        d[label="IR Generator"]
+        e[label="Pass Manager"]
+        f[label="Object Layer"]
+        g[label="Native Code"]
+        z[label="Preload Core libs"]
+        a -> b
+        b -> c {label="AST"}
+        c -> d
+        z -> f
+        subgraph cluster0 {
+            color=lightgrey;
+            d -> e -> f
+            label = "JIT Engine";
+        }
+        f -> g
+        g -> Store
+        g -> Execute
+  }
+#+END_SRC
+
+#+RESULTS: ep-14-jit-2
+[[file:/tmp/jit-2.svg]]
+
+
+- Trade off
+  Compilation speed vs Execution speed
+*** JIT vs Typical interpreters
+
+** Why to use JIT?
+- Make the interpreter to run "faster" (air quote again)
+- Speed up the compilation
+  Avoid generating the target code and generate some byte-code instead
+  and then use a JIT in runtime to execute the byte-code.
+- Use runtime data to find optimization opportunities.
+- Support more archs
+- And many other reasons
+** How we're going to use a JIT?
+- We need a JIT engine to implement Lisp Macros
+- Compile time vs Runtime
+  + Abstraction
+- A JIT engine to just compile Serene code
+- Our compiler will be a fancy JIT engine
+
+#+NAME: ep-14-jit-3
+#+BEGIN_SRC graphviz-dot :file /tmp/jit-3.svg :cmdline -Kdot -Tsvg
+  digraph {
+    graph [bgcolor=transparent]
+    node [color=gray80 shape="box"]
+    edge [color=gray80]
+    rankdir = "LR"
+
+    a[label="Serene AST"]
+    b[label="For every node"]
+    c[label="is it a macro call?" shapp="diamond"]
+    d[label="Add it to JIT"]
+    e[label="Expand it (call it)"]
+    f[label="Generate target code"]
+    a -> b
+
+
+    subgraph cluster0 {
+        color=lightgrey;
+        b -> c
+        c -> d [label="NO"]
+        c -> e [label="YES"]
+        e -> b
+        d -> f
+        label = "JIT Engine";
+    }
+
+    f -> Store
+    f -> Execute
+  }
+#+END_SRC
+
+#+RESULTS: ep-14-jit-3
+[[file:/tmp/jit-3.svg]]
+
+
+** LLVM/MLIR and JIT
+- 3 different approaches
+- MLIR's JIT
+- LLVM JITs
+  + MCJIT (Deprecated)
+  + LLJIT (Based on ORCv2)
+  + LazyLLJIT (Based on LLJIT)
+- Use LLVM's ORCv2 directly to create an engine