Optimizer docs: Add missing info about steps that destroy the SSA and…

… expression-split forms

docs/internals/optimizer.rst

@@ -466,6 +466,8 @@ Loops that already have a literal constant as iteration condition are not transf
 
 To avoid unnecessary rewriting, it is recommended to run this step after StructuralSimplifier.
 
+May destroy the :ref:`expression-split <expression-splitter>` form.
+
 Prerequisites: Disambiguator.
 
 .. _for-loop-init-rewriter:
@@ -881,6 +883,8 @@ Since variable references are always movable, even if their current
 value might not be, the ExpressionSimplifier is again more powerful
 in :ref:`expression-split <expression-splitter>` or :ref:`pseudo-SSA <ssa-transform>` form.
 
+Some of the simplifications destroy the :ref:`expression-split <expression-splitter>` form.
+
 Prerequisites: Disambiguator, ForLoopInitRewriter.
 
 .. _literal-rematerialiser:
@@ -893,6 +897,8 @@ the variable with the literal.
 
 This is mostly used so that other components do not have to rely on the DataflowAnalyzer.
 
+Destroys the :ref:`expression-split <expression-splitter>` form.
+
 Prerequisites: Disambiguator, ForLoopInitRewriter.
 
 .. _load-resolver:
@@ -931,7 +937,7 @@ ConditionalSimplifier
 The ConditionalSimplifier inserts assignments to condition variables if the value can be determined
 from the control-flow.
 
-Destroys SSA form.
+Destroys the :ref:`SSA <ssa-transform>` form.
 
 Currently, this tool is very limited, mostly because we do not yet have support
 for boolean types. Since conditions only check for expressions being nonzero,
@@ -1386,6 +1392,8 @@ Because of that, the snippet ``let x := add(0, 2) let y := mul(x, 3)`` is
 transformed to ``let y := mul(add(0, 2), 3)``, even though the ``add`` opcode
 would be executed after the evaluation of the literal ``3``.
 
+Destroys the :ref:`expression-split <expression-splitter>` form.
+
 Prerequisites: Disambiguator.
 
 .. _ssa-reverser:
@@ -1438,6 +1446,8 @@ by ``a`` (until ``a`` is re-assigned). The UnusedPruner will then
 eliminate the variable ``a_1`` altogether and thus fully reverse the
 SSATransform.
 
+Destroys the :ref:`SSA <ssa-transform>` form.
+
 Prerequisites: Disambiguator.
 
 .. _stack-compressor:
@@ -1476,6 +1486,8 @@ which are always movable.
 If the value is very cheap or the variable was explicitly requested to be eliminated,
 the variable reference is replaced by its current value.
 
+Destroys the :ref:`expression-split <expression-splitter>` form.
+
 Prerequisites: Disambiguator, ForLoopInitRewriter.
 
 .. _for-loop-condition-out-of-body: