[clang] [analyzer][NFC] Combine similar methods in StreamChecker (PR #70170)

[Ben Shi via cfe-commits]

https://github.com/benshi001 created https://github.com/llvm/llvm-project/pull/70170

Methods StreamChecker::preFread and StreamChecker::preFwrite are quite similar, so they can be combined to StreamChecker::preFreadFwrite.

>From 99a826f3a2219ea6ee368e4ffd3db8c391e9ae2c Mon Sep 17 00:00:00 2001
From: Ben Shi <bennshi at tencent.com>
Date: Wed, 25 Oct 2023 14:58:55 +0800
Subject: [PATCH] [analyzer][NFC] Combine similar methods in StreamChecker

Methods StreamChecker::preFread and StreamChecker::preFwrite are quite
similar, so they can be combined to StreamChecker::preFreadFwrite.
---
 .../StaticAnalyzer/Checkers/StreamChecker.cpp | 39 ++++++-------------
 1 file changed, 12 insertions(+), 27 deletions(-)

diff --git a/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp
index ef209f64f0c372c..843748c832ff97f 100644
--- a/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp
@@ -245,10 +245,10 @@ class StreamChecker : public Checker<check::PreCall, eval::Call,
       {{{"fclose"}, 1},
        {&StreamChecker::preDefault, &StreamChecker::evalFclose, 0}},
       {{{"fread"}, 4},
-       {&StreamChecker::preFread,
+       {std::bind(&StreamChecker::preFreadFwrite, _1, _2, _3, _4, true),
         std::bind(&StreamChecker::evalFreadFwrite, _1, _2, _3, _4, true), 3}},
       {{{"fwrite"}, 4},
-       {&StreamChecker::preFwrite,
+       {std::bind(&StreamChecker::preFreadFwrite, _1, _2, _3, _4, false),
         std::bind(&StreamChecker::evalFreadFwrite, _1, _2, _3, _4, false), 3}},
       {{{"fseek"}, 3},
        {&StreamChecker::preFseek, &StreamChecker::evalFseek, 0}},
@@ -305,11 +305,8 @@ class StreamChecker : public Checker<check::PreCall, eval::Call,
   void evalFclose(const FnDescription *Desc, const CallEvent &Call,
                   CheckerContext &C) const;
 
-  void preFread(const FnDescription *Desc, const CallEvent &Call,
-                CheckerContext &C) const;
-
-  void preFwrite(const FnDescription *Desc, const CallEvent &Call,
-                 CheckerContext &C) const;
+  void preFreadFwrite(const FnDescription *Desc, const CallEvent &Call,
+                      CheckerContext &C, bool IsFread) const;
 
   void evalFreadFwrite(const FnDescription *Desc, const CallEvent &Call,
                        CheckerContext &C, bool IsFread) const;
@@ -637,8 +634,9 @@ void StreamChecker::evalFclose(const FnDescription *Desc, const CallEvent &Call,
   C.addTransition(StateFailure);
 }
 
-void StreamChecker::preFread(const FnDescription *Desc, const CallEvent &Call,
-                             CheckerContext &C) const {
+void StreamChecker::preFreadFwrite(const FnDescription *Desc,
+                                   const CallEvent &Call, CheckerContext &C,
+                                   bool IsFread) const {
   ProgramStateRef State = C.getState();
   SVal StreamVal = getStreamArg(Desc, Call);
   State = ensureStreamNonNull(StreamVal, Call.getArgExpr(Desc->StreamArgNo), C,
@@ -652,6 +650,11 @@ void StreamChecker::preFread(const FnDescription *Desc, const CallEvent &Call,
   if (!State)
     return;
 
+  if (!IsFread) {
+    C.addTransition(State);
+    return;
+  }
+
   SymbolRef Sym = StreamVal.getAsSymbol();
   if (Sym && State->get<StreamMap>(Sym)) {
     const StreamState *SS = State->get<StreamMap>(Sym);
@@ -662,24 +665,6 @@ void StreamChecker::preFread(const FnDescription *Desc, const CallEvent &Call,
   }
 }
 
-void StreamChecker::preFwrite(const FnDescription *Desc, const CallEvent &Call,
-                              CheckerContext &C) const {
-  ProgramStateRef State = C.getState();
-  SVal StreamVal = getStreamArg(Desc, Call);
-  State = ensureStreamNonNull(StreamVal, Call.getArgExpr(Desc->StreamArgNo), C,
-                              State);
-  if (!State)
-    return;
-  State = ensureStreamOpened(StreamVal, C, State);
-  if (!State)
-    return;
-  State = ensureNoFilePositionIndeterminate(StreamVal, C, State);
-  if (!State)
-    return;
-
-  C.addTransition(State);
-}
-
 void StreamChecker::evalFreadFwrite(const FnDescription *Desc,
                                     const CallEvent &Call, CheckerContext &C,
                                     bool IsFread) const {