wip2

Author: hvitved

rust/ql/lib/codeql/rust/internal/typeinference/TypeInference.qll

@@ -1847,17 +1847,6 @@ private module AssocFunctionResolution {
   }
 }
 
-pragma[nomagic]
-private Type inferUnknownType(AstNode n, TypePath path) {
-  result = TUnknownType() and
-  path.isEmpty() and
-  (
-    n.(AssocFunctionResolution::AssocFunctionCall).resolutionDependsOnReturnType()
-    or
-    isPanicMacroCall(n)
-  )
-}
-
 pragma[nomagic]
 private Type getFieldExprLookupType(FieldExpr fe, string name, DerefChain derefChain) {
   exists(TypePath path |
@@ -1877,20 +1866,6 @@ private Type getFieldExprLookupType(FieldExpr fe, string name, DerefChain derefC
   )
 }
 
-/**
- * Gets the struct field that the field expression `fe` resolves to, if any.
- */
-cached
-StructField resolveStructFieldExpr(FieldExpr fe, DerefChain derefChain) {
-  M3::CachedStage::ref() and
-  exists(string name, DataType ty |
-    ty = getFieldExprLookupType(fe, pragma[only_bind_into](name), derefChain)
-  |
-    result = ty.(StructType).getTypeItem().getStructField(pragma[only_bind_into](name)) or
-    result = ty.(UnionType).getTypeItem().getStructField(pragma[only_bind_into](name))
-  )
-}
-
 pragma[nomagic]
 private Type getTupleFieldExprLookupType(FieldExpr fe, int pos, DerefChain derefChain) {
   exists(string name |
@@ -1899,21 +1874,6 @@ private Type getTupleFieldExprLookupType(FieldExpr fe, int pos, DerefChain deref
   )
 }
 
-/**
- * Gets the tuple field that the field expression `fe` resolves to, if any.
- */
-cached
-TupleField resolveTupleFieldExpr(FieldExpr fe, DerefChain derefChain) {
-  M3::CachedStage::ref() and
-  exists(int i |
-    result =
-      getTupleFieldExprLookupType(fe, pragma[only_bind_into](i), derefChain)
-          .(StructType)
-          .getTypeItem()
-          .getTupleField(pragma[only_bind_into](i))
-  )
-}
-
 /** Gets the root type of the reference expression `ref`. */
 pragma[nomagic]
 private Type inferRefExprType(RefExpr ref) {
@@ -2205,51 +2165,85 @@ private TupleType inferArgList(ArgList args, TypePath path) {
   )
 }
 
-/** Holds if `n` is implicitly dereferenced and/or borrowed. */
 cached
-predicate implicitDerefChainBorrow(Expr e, DerefChain derefChain, boolean borrow) {
-  M3::CachedStage::ref() and
-  exists(BorrowKind bk |
-    any(AssocFunctionResolution::AssocFunctionCall afc)
-        .argumentHasImplicitDerefChainBorrow(e, derefChain, bk) and
-    if bk.isNoBorrow() then borrow = false else borrow = true
-  )
-  or
-  e =
-    any(FieldExpr fe |
-      exists(resolveStructFieldExpr(fe, derefChain))
-      or
-      exists(resolveTupleFieldExpr(fe, derefChain))
-    ).getContainer() and
-  not derefChain.isEmpty() and
-  borrow = false
-}
+private module Cached {
+  /** Holds if `n` is implicitly dereferenced and/or borrowed. */
+  cached
+  predicate implicitDerefChainBorrow(Expr e, DerefChain derefChain, boolean borrow) {
+    M3::CachedStage::ref() and
+    exists(BorrowKind bk |
+      any(AssocFunctionResolution::AssocFunctionCall afc)
+          .argumentHasImplicitDerefChainBorrow(e, derefChain, bk) and
+      if bk.isNoBorrow() then borrow = false else borrow = true
+    )
+    or
+    e =
+      any(FieldExpr fe |
+        exists(resolveStructFieldExpr(fe, derefChain))
+        or
+        exists(resolveTupleFieldExpr(fe, derefChain))
+      ).getContainer() and
+    not derefChain.isEmpty() and
+    borrow = false
+  }
 
-/**
- * Gets an item (function or tuple struct/variant) that `call` resolves to, if
- * any.
- *
- * The parameter `dispatch` is `true` if and only if the resolved target is a
- * trait item because a precise target could not be determined from the
- * types (for instance in the presence of generics or `dyn` types)
- */
-cached
-Addressable resolveCallTarget(InvocationExpr call, boolean dispatch) {
-  M3::CachedStage::ref() and
-  dispatch = false and
-  result = call.(NonAssocCallExpr).resolveCallTargetViaPathResolution()
-  or
-  exists(ImplOrTraitItemNode i |
-    i instanceof TraitItemNode and dispatch = true
+  /**
+   * Gets an item (function or tuple struct/variant) that `call` resolves to, if
+   * any.
+   *
+   * The parameter `dispatch` is `true` if and only if the resolved target is a
+   * trait item because a precise target could not be determined from the
+   * types (for instance in the presence of generics or `dyn` types)
+   */
+  cached
+  Addressable resolveCallTarget(InvocationExpr call, boolean dispatch) {
+    M3::CachedStage::ref() and
+    dispatch = false and
+    result = call.(NonAssocCallExpr).resolveCallTargetViaPathResolution()
     or
-    i instanceof ImplItemNode and dispatch = false
-  |
-    result = call.(AssocFunctionResolution::AssocFunctionCall).resolveCallTarget(i, _, _, _) and
-    not call instanceof CallExprImpl::DynamicCallExpr and
-    not i instanceof Builtins::BuiltinImpl
-  )
+    exists(ImplOrTraitItemNode i |
+      i instanceof TraitItemNode and dispatch = true
+      or
+      i instanceof ImplItemNode and dispatch = false
+    |
+      result = call.(AssocFunctionResolution::AssocFunctionCall).resolveCallTarget(i, _, _, _) and
+      not call instanceof CallExprImpl::DynamicCallExpr and
+      not i instanceof Builtins::BuiltinImpl
+    )
+  }
+
+  /**
+   * Gets the struct field that the field expression `fe` resolves to, if any.
+   */
+  cached
+  StructField resolveStructFieldExpr(FieldExpr fe, DerefChain derefChain) {
+    M3::CachedStage::ref() and
+    exists(string name, DataType ty |
+      ty = getFieldExprLookupType(fe, pragma[only_bind_into](name), derefChain)
+    |
+      result = ty.(StructType).getTypeItem().getStructField(pragma[only_bind_into](name)) or
+      result = ty.(UnionType).getTypeItem().getStructField(pragma[only_bind_into](name))
+    )
+  }
+
+  /**
+   * Gets the tuple field that the field expression `fe` resolves to, if any.
+   */
+  cached
+  TupleField resolveTupleFieldExpr(FieldExpr fe, DerefChain derefChain) {
+    M3::CachedStage::ref() and
+    exists(int i |
+      result =
+        getTupleFieldExprLookupType(fe, pragma[only_bind_into](i), derefChain)
+            .(StructType)
+            .getTypeItem()
+            .getTupleField(pragma[only_bind_into](i))
+    )
+  }
 }
 
+import Cached
+
 private module Input3 implements InputSig3 {
   private import rust as Rust
   private import codeql.rust.elements.internal.OperationImpl::Impl as OperationImpl
@@ -3108,6 +3102,17 @@ private module Input3 implements InputSig3 {
     )
   }
 
+  pragma[nomagic]
+  private Type inferUnknownType(AstNode n, TypePath path) {
+    result = TUnknownType() and
+    path.isEmpty() and
+    (
+      n.(AssocFunctionResolution::AssocFunctionCall).resolutionDependsOnReturnType()
+      or
+      isPanicMacroCall(n)
+    )
+  }
+
   pragma[nomagic]
   Type inferTypeSpecific(AstNode n, TypePath path) {
     result = inferAssignmentOperationType(n, path)