Merge pull request #20485 from MathiasVP/use-shared-guards-library

C++: Switch to the shared Guards library

Author: jketema

cpp/ql/lib/change-notes/2025-09-18-guards.md

@@ -0,0 +1,4 @@
+---
+category: breaking
+---
+* The "Guards" libraries (`semmle.code.cpp.controlflow.Guards` and `semmle.code.cpp.controlflow.IRGuards`) have been totally rewritten to recognize many more guards. The API remains unchanged, but the `GuardCondition` class now extends `Element` instead of `Expr`.

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/RangeAnalysis.qll

@@ -412,7 +412,7 @@ private predicate boundFlowStepPhi(
   or
   exists(IRGuardCondition guard, boolean testIsTrue |
     guard = boundFlowCond(valueNumberOfOperand(op2), op1, delta, upper, testIsTrue) and
-    guard.controlsEdge(op2.getPredecessorBlock(), op2.getUse().getBlock(), testIsTrue) and
+    guard.controlsBranchEdge(op2.getPredecessorBlock(), op2.getUse().getBlock(), testIsTrue) and
     reason = TCondReason(guard)
   )
 }