QL: Merge pull request #69 from github/erik-krogh/perf

fix two bad join orders

Author: MathiasVP

ql/src/codeql_ql/ast/internal/Module.qll

@@ -74,23 +74,6 @@ private class Folder_ extends ContainerOrModule, TFolder {
   Folder getFolder() { result = f }
 }
 
-// TODO: Use `AstNode::getParent` once it is total
-private Generated::AstNode parent(Generated::AstNode n) {
-  result = n.getParent() and
-  not n instanceof Generated::Module
-}
-
-private Module getEnclosingModule0(AstNode n) {
-  AstNodes::toGenerated(result) = parent*(AstNodes::toGenerated(n).getParent())
-}
-
-ContainerOrModule getEnclosingModule(AstNode n) {
-  result = TModule(getEnclosingModule0(n))
-  or
-  not exists(getEnclosingModule0(n)) and
-  result = TFile(n.getLocation().getFile())
-}
-
 class Module_ extends FileOrModule, TModule {
   Module m;
 
@@ -163,6 +146,24 @@ private predicate resolveSelectionName(Import imp, ContainerOrModule m, int i) {
 
 cached
 private module Cached {
+  // TODO: Use `AstNode::getParent` once it is total
+  private Generated::AstNode parent(Generated::AstNode n) {
+    result = n.getParent() and
+    not n instanceof Generated::Module
+  }
+
+  private Module getEnclosingModule0(AstNode n) {
+    AstNodes::toGenerated(result) = parent*(AstNodes::toGenerated(n).getParent())
+  }
+
+  cached
+  ContainerOrModule getEnclosingModule(AstNode n) {
+    result = TModule(getEnclosingModule0(n))
+    or
+    not exists(getEnclosingModule0(n)) and
+    result = TFile(n.getLocation().getFile())
+  }
+
   cached
   module NewType {
     cached

ql/src/codeql_ql/ast/internal/Type.qll

@@ -76,7 +76,7 @@ class Type extends TType {
     p2 = classPredCandidate(this, name, arity)
   }
 
-  pragma[nomagic]
+  cached
   PredicateOrBuiltin getClassPredicate(string name, int arity) {
     result = classPredCandidate(this, name, arity) and
     not getClassPredicate1(name, arity, _, result)

ql/src/codeql_ql/ast/internal/Variable.qll

@@ -72,7 +72,9 @@ private module Cached {
   predicate resolveVariable(Identifier i, VarDef decl) { scopeOf(i).containsVar(decl, getName(i)) }
 
   cached
-  predicate resolveField(Identifier i, VarDef decl) { scopeOf(i).containsField(decl, getName(i)) }
+  predicate resolveField(Identifier i, VarDef decl) {
+    scopeOf(i).containsField(decl, pragma[only_bind_into](getName(i)))
+  }
 }
 
 import Cached