[analyzer] NFC: Change evalCall() to provide a CallEvent.

This changes the checker callback signature to use the modern, easy to
use interface. Additionally, this unblocks future work on allowing
checkers to implement evalCall() for calls that don't correspond to any
call-expression or require additional information that's only available
as part of the CallEvent, such as C++ constructors and destructors.

Differential Revision: https://reviews.llvm.org/D62440

llvm-svn: 363893

1 files changed, 20 insertions, 37 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/ChrootChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/ChrootChecker.cpp
index cbc5b32931b..9fffedfccd8 100644
--- a/clang/lib/StaticAnalyzer/Checkers/ChrootChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/ChrootChecker.cpp
@@ -14,6 +14,7 @@
 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
 #include "clang/StaticAnalyzer/Core/Checker.h"
 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
@@ -37,53 +38,44 @@ bool isRootChanged(intptr_t k) { return k == ROOT_CHANGED; }
 //         ROOT_CHANGED<--chdir(..)--      JAIL_ENTERED<--chdir(..)--
 //                                  |                               |
 //                      bug<--foo()--          JAIL_ENTERED<--foo()--
-class ChrootChecker : public Checker<eval::Call, check::PreStmt<CallExpr> > {
-  mutable IdentifierInfo *II_chroot, *II_chdir;
+class ChrootChecker : public Checker<eval::Call, check::PreCall> {
   // This bug refers to possibly break out of a chroot() jail.
   mutable std::unique_ptr<BuiltinBug> BT_BreakJail;
 
+  const CallDescription Chroot{"chroot", 1}, Chdir{"chdir", 1};
+
 public:
-  ChrootChecker() : II_chroot(nullptr), II_chdir(nullptr) {}
+  ChrootChecker() {}
 
   static void *getTag() {
     static int x;
     return &x;
   }
 
-  bool evalCall(const CallExpr *CE, CheckerContext &C) const;
-  void checkPreStmt(const CallExpr *CE, CheckerContext &C) const;
+  bool evalCall(const CallEvent &Call, CheckerContext &C) const;
+  void checkPreCall(const CallEvent &Call, CheckerContext &C) const;
 
 private:
-  void Chroot(CheckerContext &C, const CallExpr *CE) const;
-  void Chdir(CheckerContext &C, const CallExpr *CE) const;
+  void evalChroot(const CallEvent &Call, CheckerContext &C) const;
+  void evalChdir(const CallEvent &Call, CheckerContext &C) const;
 };
 
 } // end anonymous namespace
 
-bool ChrootChecker::evalCall(const CallExpr *CE, CheckerContext &C) const {
-  const FunctionDecl *FD = C.getCalleeDecl(CE);
-  if (!FD)
-    return false;
-
-  ASTContext &Ctx = C.getASTContext();
-  if (!II_chroot)
-    II_chroot = &Ctx.Idents.get("chroot");
-  if (!II_chdir)
-    II_chdir = &Ctx.Idents.get("chdir");
-
-  if (FD->getIdentifier() == II_chroot) {
-    Chroot(C, CE);
+bool ChrootChecker::evalCall(const CallEvent &Call, CheckerContext &C) const {
+  if (Call.isCalled(Chroot)) {
+    evalChroot(Call, C);
     return true;
   }
-  if (FD->getIdentifier() == II_chdir) {
-    Chdir(C, CE);
+  if (Call.isCalled(Chdir)) {
+    evalChdir(Call, C);
     return true;
   }
 
   return false;
 }
 
-void ChrootChecker::Chroot(CheckerContext &C, const CallExpr *CE) const {
+void ChrootChecker::evalChroot(const CallEvent &Call, CheckerContext &C) const {
   ProgramStateRef state = C.getState();
   ProgramStateManager &Mgr = state->getStateManager();
 
@@ -93,7 +85,7 @@ void ChrootChecker::Chroot(CheckerContext &C, const CallExpr *CE) const {
   C.addTransition(state);
 }
 
-void ChrootChecker::Chdir(CheckerContext &C, const CallExpr *CE) const {
+void ChrootChecker::evalChdir(const CallEvent &Call, CheckerContext &C) const {
   ProgramStateRef state = C.getState();
   ProgramStateManager &Mgr = state->getStateManager();
 
@@ -103,7 +95,7 @@ void ChrootChecker::Chdir(CheckerContext &C, const CallExpr *CE) const {
     return;
 
   // After chdir("/"), enter the jail, set the enum value JAIL_ENTERED.
-  const Expr *ArgExpr = CE->getArg(0);
+  const Expr *ArgExpr = Call.getArgExpr(0);
   SVal ArgVal = C.getSVal(ArgExpr);
 
   if (const MemRegion *R = ArgVal.getAsRegion()) {
@@ -120,19 +112,10 @@ void ChrootChecker::Chdir(CheckerContext &C, const CallExpr *CE) const {
 }
 
 // Check the jail state before any function call except chroot and chdir().
-void ChrootChecker::checkPreStmt(const CallExpr *CE, CheckerContext &C) const {
-  const FunctionDecl *FD = C.getCalleeDecl(CE);
-  if (!FD)
-    return;
-
-  ASTContext &Ctx = C.getASTContext();
-  if (!II_chroot)
-    II_chroot = &Ctx.Idents.get("chroot");
-  if (!II_chdir)
-    II_chdir = &Ctx.Idents.get("chdir");
-
+void ChrootChecker::checkPreCall(const CallEvent &Call,
+                                 CheckerContext &C) const {
   // Ignore chroot and chdir.
-  if (FD->getIdentifier() == II_chroot || FD->getIdentifier() == II_chdir)
+  if (Call.isCalled(Chroot) || Call.isCalled(Chdir))
     return;
 
   // If jail state is ROOT_CHANGED, generate BugReport.