[Analyzer] More accurate modeling about the increment operator of the operand with type bool.
Summary:
There is a problem with analyzer that a wrong value is given when modeling the increment operator of the operand with type bool. After `rL307604` is applied, a unsigned overflow may occur.
Example:
```
void func() {
bool b = true;
// unsigned overflow occur, 2 -> 0 U1b
b++;
}
```
The use of an operand of type bool with the ++ operators is deprecated but valid untill C++17. And if the operand of the increment operator is of type bool, it is set to true.
This patch includes two parts:
- If the operand of the increment operator is of type bool or type _Bool, set to true.
- Modify `BasicValueFactory::getTruthValue()`, use `getIntWidth()` instead `getTypeSize()` and use `unsigned` instead `signed`.
Reviewers: alexshap, NoQ, dcoughlin, george.karpenkov
Reviewed By: NoQ
Subscribers: xazax.hun, szepet, a.sidorin, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D43741
llvm-svn: 326776