[devdocs] update AST.md#CodeInfo descriptions (JuliaLang#43382)

Co-authored-by: Shuhei Kadowaki <[email protected]>

doc/src/devdocs/ast.md

@@ -699,11 +699,13 @@ A (usually temporary) container for holding lowered source code.
 
  Statement-level flags for each expression in the function. Many of these are reserved, but not yet implemented:
 
- * 0 = inbounds
- * 1,2 = <reserved> inlinehint,always-inline,noinline
- * 3 = <reserved> strict-ieee (strictfp)
- * 4-6 = <unused>
- * 7 = <reserved> has out-of-band info
+ * 0x01 << 0 = statement is marked as `@inbounds`
+ * 0x01 << 1 = statement is marked as `@inline`
+ * 0x01 << 2 = statement is marked as `@noinline`
+ * 0x01 << 3 = statement is within a block that leads to `throw` call
+ * 0x01 << 4 = statement may be removed if its result is unused, in particular it is thus be both pure and effect free
+ * 0x01 << 5-6 = <unused>
+ * 0x01 << 7 = <reserved> has out-of-band info
 
  * `linetable`
 
@@ -733,6 +735,10 @@ Optional Fields:
 
  The `MethodInstance` that "owns" this object (if applicable).
 
+ * `edges`
+
+ Forward edges to method instances that must be invalidated.
+
  * `min_world`/`max_world`
 
  The range of world ages for which this code was valid at the time when it had been inferred.
@@ -757,3 +763,23 @@ Boolean properties:
 
  Whether this is known to be a pure function of its arguments, without respect to the
  state of the method caches or other mutable global state.
+
+
+`UInt8` settings:
+
+ * `constprop`
+
+ * 0 = use heuristic
+ * 1 = aggressive
+ * 2 = none
+
+ * `purity`
+ Constructed from 5 bit flags:
+
+ * 0x01 << 0 = this method is guaranteed to return or terminate consistently (`:consistent`)
+ * 0x01 << 1 = this method is free from externally semantically visible side effects (`:effect_free`)
+ * 0x01 << 2 = this method is guaranteed to not throw an exception (`:nothrow`)
+ * 0x01 << 3 = this method is guaranteed to terminate (`:terminates_globally`)
+ * 0x01 << 4 = the syntactic control flow within this method is guaranteed to terminate (`:terminates_locally`)
+
+ See the documentation of `Base.@assume_effects` for more details.