Ruby: Rework call graph implementation

ruby/ql/consistency-queries/DataFlowConsistency.ql

@@ -1,3 +1,4 @@
+import codeql.ruby.AST
 import codeql.ruby.DataFlow::DataFlow
 import codeql.ruby.dataflow.internal.DataFlowPrivate
 import codeql.ruby.dataflow.internal.DataFlowImplConsistency::Consistency
@@ -11,5 +12,7 @@ private class MyConsistencyConfiguration extends ConsistencyConfiguration {
     n instanceof SummaryNode
     or
     n instanceof SynthHashSplatArgumentNode
+    or
+    not isNonConstantExpr(n.asExpr())
   }
 }

ruby/ql/lib/codeql/ruby/ast/internal/Module.qll

@@ -137,14 +137,7 @@ private module Cached {
   }
 
   cached
-  Method lookupMethod(Module m, string name) {
-    // The syntax_suggest library redefines Kernel.require/require_relative.
-    // Somehow this causes performance issues on ruby/ruby. As a workaround
-    // we exclude 'require' and 'require_relative'.
-    // TODO: find the actual cause of the slowdown and fix things properly.
-    not name = ["require", "require_relative"] and
-    TMethod(result) = lookupMethodOrConst(m, name)
-  }
+  Method lookupMethod(Module m, string name) { TMethod(result) = lookupMethodOrConst(m, name) }
 
   cached
   Expr lookupConst(Module m, string name) {

ruby/ql/lib/codeql/ruby/controlflow/BasicBlocks.qll

@@ -311,13 +311,13 @@ private module Cached {
   }
 
   cached
-  predicate immediatelyControls(ConditionBlock cb, BasicBlock succ, BooleanSuccessor s) {
+  predicate immediatelyControls(ConditionBlock cb, BasicBlock succ, ConditionalSuccessor s) {
     succ = cb.getASuccessor(s) and
     forall(BasicBlock pred | pred = succ.getAPredecessor() and pred != cb | succ.dominates(pred))
   }
 
   cached
-  predicate controls(ConditionBlock cb, BasicBlock controlled, BooleanSuccessor s) {
+  predicate controls(ConditionBlock cb, BasicBlock controlled, ConditionalSuccessor s) {
     exists(BasicBlock succ | cb.immediatelyControls(succ, s) | succ.dominates(controlled))
   }
 }
@@ -406,7 +406,7 @@ class ConditionBlock extends BasicBlock {
    * successor of this block, and `succ` can only be reached from
    * the callable entry point by going via the `s` edge out of this basic block.
    */
-  predicate immediatelyControls(BasicBlock succ, BooleanSuccessor s) {
+  predicate immediatelyControls(BasicBlock succ, ConditionalSuccessor s) {
     immediatelyControls(this, succ, s)
   }
 
@@ -415,5 +415,7 @@ class ConditionBlock extends BasicBlock {
    * conditional value `s`. That is, `controlled` can only be reached from
    * the callable entry point by going via the `s` edge out of this basic block.
    */
-  predicate controls(BasicBlock controlled, BooleanSuccessor s) { controls(this, controlled, s) }
+  predicate controls(BasicBlock controlled, ConditionalSuccessor s) {
+    controls(this, controlled, s)
+  }
 }

ruby/ql/lib/codeql/ruby/controlflow/CfgNodes.qll

@@ -433,7 +433,7 @@ module ExprNodes {
   }
 
   private class WhenClauseChildMapping extends NonExprChildMapping, WhenClause {
-    override predicate relevantChild(AstNode e) { e = this.getBody() }
+    override predicate relevantChild(AstNode e) { e = [this.getBody(), this.getAPattern()] }
   }
 
   /** A control-flow node that wraps a `WhenClause` AST expression. */
@@ -444,6 +444,9 @@ module ExprNodes {
 
     /** Gets the body of this `when`-clause. */
     final ExprCfgNode getBody() { e.hasCfgChild(e.getBody(), this, result) }
+
+    /** Gets the `i`th pattern this `when`-clause. */
+    final ExprCfgNode getPattern(int i) { e.hasCfgChild(e.getPattern(i), this, result) }
   }
 
   /** A control-flow node that wraps a `CasePattern`. */

ruby/ql/lib/codeql/ruby/controlflow/ControlFlowGraph.qll

@@ -44,7 +44,7 @@ class CfgNode extends TCfgNode {
   final File getFile() { result = this.getLocation().getFile() }
 
   /** Holds if this control flow node has conditional successors. */
-  final predicate isCondition() { exists(this.getASuccessor(any(BooleanSuccessor bs))) }
+  final predicate isCondition() { exists(this.getASuccessor(any(ConditionalSuccessor bs))) }
 
   /** Gets the scope of this node. */
   final CfgScope getScope() { result = getNodeCfgScope(this) }