Swift: Comment some other cases.

geoffw0 · geoffw0 · commit 6ffe5fcaed2f · 2022-08-10T15:46:32.000+01:00
diff --git a/swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll b/swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll
@@ -108,11 +108,13 @@ private module Cached {
       localFlowSsaInput(nodeFrom, def, nodeTo.asDefinition())
     )
     or
+    // flow through writes to inout parameters
     exists(ParamReturnKind kind, ExprCfgNode arg |
       arg = nodeFrom.(InOutUpdateNode).getCall(kind).asCall().getArgument(kind.getIndex()) and
       nodeTo.asDefinition().(Ssa::WriteDefinition).isInoutDef(arg)
     )
     or
+    // flow through `&` (inout argument)
     nodeFrom.asExpr() = nodeTo.asExpr().(InOutExpr).getSubExpr()
     or
     // flow through `try!` and similar constructs

Original file line number	Diff line number	Diff line change
`@@ -108,11 +108,13 @@ private module Cached {`
`108`	`108`	`localFlowSsaInput(nodeFrom, def, nodeTo.asDefinition())`
`109`	`109`	`)`
`110`	`110`	`or`
	`111`	`+ // flow through writes to inout parameters`
`111`	`112`	`exists(ParamReturnKind kind, ExprCfgNode arg \|`
`112`	`113`	`arg = nodeFrom.(InOutUpdateNode).getCall(kind).asCall().getArgument(kind.getIndex()) and`
`113`	`114`	`nodeTo.asDefinition().(Ssa::WriteDefinition).isInoutDef(arg)`
`114`	`115`	`)`
`115`	`116`	`or`
	`117`	+ // flow through `&` (inout argument)
`116`	`118`	`nodeFrom.asExpr() = nodeTo.asExpr().(InOutExpr).getSubExpr()`
`117`	`119`	`or`
`118`	`120`	// flow through `try!` and similar constructs