[static analyzer] Fix crash on parenthesized expression in assume attribute (#151682)

- Closes #151529

`ParenExpr` should be ignored before reaching `ExprEngine::Visit`.
Failing to do so triggers the assertion.

Author: el-ev

clang/docs/ReleaseNotes.rst

@@ -247,6 +247,8 @@ New features
 
 Crash and bug fixes
 ^^^^^^^^^^^^^^^^^^^
+- Fixed a crash in the static analyzer that when the expression in an 
+  ``[[assume(expr)]]`` attribute was enclosed in parentheses.  (#GH151529)
 
 Improvements
 ^^^^^^^^^^^^

clang/lib/StaticAnalyzer/Core/ExprEngineCXX.cpp

@@ -1227,7 +1227,7 @@ void ExprEngine::VisitAttributedStmt(const AttributedStmt *A,
 
   for (const auto *Attr : getSpecificAttrs<CXXAssumeAttr>(A->getAttrs())) {
     for (ExplodedNode *N : CheckerPreStmt) {
-      Visit(Attr->getAssumption(), N, EvalSet);
+      Visit(Attr->getAssumption()->IgnoreParens(), N, EvalSet);
     }
   }
 

clang/test/Analysis/builtin_assume.cpp

@@ -62,3 +62,16 @@ int using_builtin_assume_has_no_sideeffects(int y) {
 
   return y;
 }
+
+template <int ...args>
+bool issue151529() {
+  // no-crash
+  [[assume((true))]]; 
+  // no-crash
+  [[assume(((args >= 0) && ...))]];  // expected-warning {{pack fold expression is a C++17 extension}}
+  return ((args >= 0) && ...); // expected-warning {{pack fold expression is a C++17 extension}}
+}
+
+void instantiate_issue151529() {
+  issue151529<0>();
+}