C++: Remove unused case for now, and add QLDoc.

geoffw0 · geoffw0 · commit 5caa49aeab74 · 2024-02-01T15:51:50.000Z
diff --git a/cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowPrivate.qll b/cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowPrivate.qll
@@ -443,7 +443,7 @@ newtype TPosition =
 private newtype TReturnKind =
   TNormalReturnKind(int indirectionIndex) {
     Ssa::hasIndirectOperand(any(ReturnValueInstruction ret).getReturnAddressOperand(),
-      indirectionIndex + 1) // We subtract one because the return loads the value.
+      indirectionIndex + 1) // `indirectionIndex` is one less than the argument because the return loads the value.
     or
     indirectionIndex = 0 // TODO: very much a bodge so that it works on the test that has no return statements
   } or
diff --git a/cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowUtil.qll b/cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowUtil.qll
@@ -56,8 +56,7 @@ private newtype TIRDataFlowNode =
     hasFinalParameterNode(_, p, indirectionIndex)
   } or
   TFinalGlobalValue(Ssa::GlobalUse globalUse) or
-  TInitialGlobalValue(Ssa::GlobalDef globalUse) or
-  FlowSummaryNode(FlowSummaryImpl::Private::SummaryNode sn)
+  TInitialGlobalValue(Ssa::GlobalDef globalUse)
 
 /**
  * Holds if `(p, indirectionIndex)` should define a `TFinalParameterNode`
diff --git a/cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/SsaInternals.qll b/cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/SsaInternals.qll
@@ -70,6 +70,11 @@ private module SourceVariables {
 
 import SourceVariables
 
+/**
+ * Holds if `indirectionIndex` is a valid non-zero indirection index for
+ * operand `op`. That is, `indirectionIndex` is between 1 and the maximum
+ * indirection for the operand's type.
+ */
 predicate hasIndirectOperand(Operand op, int indirectionIndex) {
   exists(CppType type, int m |
     not ignoreOperand(op) and
