[all-commits] [llvm/llvm-project] 3ebf3d: [analyzer] Simplify SVal for simple NonLoc->Loc ca...

[Ding Fei via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3ebf3dd30da219f9f9aee12f42d45d18d55e7580
      https://github.com/llvm/llvm-project/commit/3ebf3dd30da219f9f9aee12f42d45d18d55e7580
  Author: Ding Fei <fding at feysh.com>
  Date:   2023-09-15 (Fri, 15 Sep 2023)

  Changed paths:
    M clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
    M clang/test/Analysis/symbol-simplification-nonloc-loc.cpp

  Log Message:
  -----------
  [analyzer] Simplify SVal for simple NonLoc->Loc casts (#66463)

NonLoc symbolic SVal to Loc casts are not supported except for
nonloc::ConcreteInt.

This change simplifies the source SVals so that the more casts can go
through nonloc::ConcreteInt->loc::ConcreteInt path. For example:

```c
  void test_simplified_before_cast_add(long long t1) {
    long long t2 = t1 + 3;
    if (!t2) {
      int *p = (int *) t2;
      clang_analyzer_eval(p == 0); // expected-warning{{TRUE}}
    }
  }
```
If simplified, `t2` is 0, resulting `p` is nullptr, otherwise `p` is
unknown.

Fixes #62232