[PATCH] D124658: CSA Normalize SymIntExpr so the RHS is positive when possible

[Tomasz Kamiński via Phabricator via cfe-commits]

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This PR changes the SymIntExpr so the expression that uses
negative value as RHS, for example: x +/- (-N), are modeled as
as x -/+ N. This avoid producing very large RHS in case when the
symbol is cased to unsigned number, and as consequence makes the
value more robust in presence of cast.
This change is not apllied if N is lowest negative value for
which negation would not be representable.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D124658

Files:
  clang/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
  clang/test/Analysis/additive-op-on-sym-int-expr.c
  clang/test/Analysis/expr-inspection.c

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