[analyzer] Add a debug analyzer config to place an event for each tracked condition

Differential Revision: https://reviews.llvm.org/D63642

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@365208 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/StaticAnalyzer/Core/AnalyzerOptions.def

@@ -296,6 +296,10 @@ ANALYZER_OPTION(bool, ShouldTrackConditions, "track-conditions",
                 "an already tracked variable.",
                 false)
 
+ANALYZER_OPTION(bool, ShouldTrackConditionsDebug, "track-conditions-debug",
+                "Whether to place an event at each tracked condition.",
+                false)
+
 //===----------------------------------------------------------------------===//
 // Unsinged analyzer options.
 //===----------------------------------------------------------------------===//

lib/Frontend/CompilerInvocation.cpp

@@ -467,6 +467,10 @@ static void parseAnalyzerConfigs(AnalyzerOptions &AnOpts,
   if (!Diags)
     return;
 
+  if (AnOpts.ShouldTrackConditionsDebug && !AnOpts.ShouldTrackConditions)
+    Diags->Report(diag::err_analyzer_config_invalid_input)
+        << "track-conditions-debug" << "'track-conditions' to also be enabled";
+
   if (!AnOpts.CTUDir.empty() && !llvm::sys::fs::is_directory(AnOpts.CTUDir))
     Diags->Report(diag::err_analyzer_config_invalid_input) << "ctu-dir"
                                                            << "a filename";

lib/StaticAnalyzer/Core/BugReporterVisitors.cpp

@@ -1667,6 +1667,26 @@ static CFGBlock *GetRelevantBlock(const ExplodedNode *Node) {
   return nullptr;
 }
 
+static std::shared_ptr<PathDiagnosticEventPiece>
+constructDebugPieceForTrackedCondition(const Expr *Cond,
+                                       const ExplodedNode *N,
+                                       BugReporterContext &BRC) {
+
+  if (BRC.getAnalyzerOptions().AnalysisDiagOpt == PD_NONE ||
+      !BRC.getAnalyzerOptions().ShouldTrackConditionsDebug)
+    return nullptr;
+
+  std::string ConditionText = Lexer::getSourceText(
+      CharSourceRange::getTokenRange(Cond->getSourceRange()),
+                                     BRC.getSourceManager(),
+                                     BRC.getASTContext().getLangOpts());
+
+  return std::make_shared<PathDiagnosticEventPiece>(
+      PathDiagnosticLocation::createBegin(
+          Cond, BRC.getSourceManager(), N->getLocationContext()),
+          (Twine() + "Tracking condition '" + ConditionText + "'").str());
+}
+
 std::shared_ptr<PathDiagnosticPiece>
 TrackControlDependencyCondBRVisitor::VisitNode(const ExplodedNode *N,
                                                BugReporterContext &BRC,
@@ -1695,6 +1715,7 @@ TrackControlDependencyCondBRVisitor::VisitNode(const ExplodedNode *N,
       if (BR.addTrackedCondition(N)) {
         bugreporter::trackExpressionValue(
             N, Condition, BR, /*EnableNullFPSuppression=*/false);
+        return constructDebugPieceForTrackedCondition(Condition, N, BRC);
       }
     }
   }

test/Analysis/analyzer-config.c

@@ -85,8 +85,9 @@
 // CHECK-NEXT: suppress-inlined-defensive-checks = true
 // CHECK-NEXT: suppress-null-return-paths = true
 // CHECK-NEXT: track-conditions = false
+// CHECK-NEXT: track-conditions-debug = false
 // CHECK-NEXT: unix.DynamicMemoryModeling:Optimistic = false
 // CHECK-NEXT: unroll-loops = false
 // CHECK-NEXT: widen-loops = false
 // CHECK-NEXT: [stats]
-// CHECK-NEXT: num-entries = 86
+// CHECK-NEXT: num-entries = 87

test/Analysis/track-control-dependency-conditions.cpp

@@ -3,7 +3,23 @@
 // RUN:   -analyzer-config track-conditions=true \
 // RUN:   -analyzer-output=text \
 // RUN:   -analyzer-checker=core
+
+// RUN: not %clang_analyze_cc1 -verify %s \
+// RUN:   -analyzer-checker=core \
+// RUN:   -analyzer-config track-conditions-debug=true \
+// RUN:   2>&1 | FileCheck %s -check-prefix=CHECK-INVALID-DEBUG
+
+// CHECK-INVALID-DEBUG: (frontend): invalid input for analyzer-config option
+// CHECK-INVALID-DEBUG-SAME:        'track-conditions-debug', that expects
+// CHECK-INVALID-DEBUG-SAME:        'track-conditions' to also be enabled
 //
+// RUN: %clang_analyze_cc1 %s \
+// RUN:   -verify=expected,tracking,debug \
+// RUN:   -analyzer-config track-conditions=true \
+// RUN:   -analyzer-config track-conditions-debug=true \
+// RUN:   -analyzer-output=text \
+// RUN:   -analyzer-checker=core
+
 // RUN: %clang_analyze_cc1 %s -verify \
 // RUN:   -analyzer-output=text \
 // RUN:   -analyzer-checker=core
@@ -30,6 +46,8 @@ void test() {
 
   if (flag) // expected-note   {{Assuming 'flag' is not equal to 0}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
+
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }
@@ -59,6 +77,8 @@ void test() {
 
   if (flag) // expected-note   {{Assuming 'flag' is not equal to 0}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
+
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }
@@ -85,8 +105,11 @@ void test() {
 
   if (bar) // expected-note   {{Assuming 'bar' is not equal to 0}}
            // expected-note@-1{{Taking true branch}}
+           // debug-note@-2{{Tracking condition 'bar'}}
     if (flag) // expected-note   {{Assuming 'flag' is not equal to 0}}
               // expected-note@-1{{Taking true branch}}
+              // debug-note@-2{{Tracking condition 'flag'}}
+
       *x = 5; // expected-warning{{Dereference of null pointer}}
               // expected-note@-1{{Dereference of null pointer}}
 }
@@ -107,7 +130,7 @@ void test() {
   if (int flag = foo()) // tracking-note{{Calling 'foo'}}
                         // tracking-note@-1{{Returning from 'foo'}}
                         // tracking-note@-2{{'flag' initialized here}}
-
+                        // debug-note@-3{{Tracking condition 'flag'}}
                         // expected-note@-4{{Assuming 'flag' is not equal to 0}}
                         // expected-note@-5{{Taking true branch}}
 
@@ -129,7 +152,7 @@ void test() {
   if (ConvertsToBool())
     // tracking-note@-1 {{Calling 'ConvertsToBool::operator bool'}}
     // tracking-note@-2{{Returning from 'ConvertsToBool::operator bool'}}
-
+    // debug-note@-3{{Tracking condition 'ConvertsToBool()'}}
     // expected-note@-4{{Assuming the condition is true}}
     // expected-note@-5{{Taking true branch}}
     *x = 5; // expected-warning{{Dereference of null pointer}}
@@ -150,8 +173,9 @@ void i(int *ptr) {
   if (!flipCoin())
     // tracking-note@-1{{Calling 'flipCoin'}}
     // tracking-note@-2{{Returning from 'flipCoin'}}
-    // expected-note@-3{{Assuming the condition is true}}
-    // expected-note@-4{{Taking true branch}}
+    // debug-note@-3{{Tracking condition '!flipCoin()'}}
+    // expected-note@-4{{Assuming the condition is true}}
+    // expected-note@-5{{Taking true branch}}
     *ptr = 5; // expected-warning{{Dereference of null pointer}}
               // expected-note@-1{{Dereference of null pointer}}
 }
@@ -163,6 +187,7 @@ bool coin();
 bool flipCoin() {
   if (coin()) // tracking-note{{Assuming the condition is false}}
               // tracking-note@-1{{Taking false branch}}
+              // debug-note@-2{{Tracking condition 'coin()'}}
     return true;
   return coin(); // tracking-note{{Returning value}}
 }
@@ -174,8 +199,9 @@ void i(int *ptr) {
   if (!flipCoin())
     // tracking-note@-1{{Calling 'flipCoin'}}
     // tracking-note@-2{{Returning from 'flipCoin'}}
-    // expected-note@-3{{Assuming the condition is true}}
-    // expected-note@-4{{Taking true branch}}
+    // debug-note@-3{{Tracking condition '!flipCoin()'}}
+    // expected-note@-4{{Assuming the condition is true}}
+    // expected-note@-5{{Taking true branch}}
     *ptr = 5; // expected-warning{{Dereference of null pointer}}
               // expected-note@-1{{Dereference of null pointer}}
 }
@@ -189,6 +215,7 @@ void f() {
   int *x = 0; // expected-note{{'x' initialized to a null pointer value}}
   if (flag) // expected-note{{Assuming 'flag' is not equal to 0}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }
@@ -205,6 +232,7 @@ void f(int y) {
   int *x = 0; // expected-note{{'x' initialized to a null pointer value}}
   if (flag) // expected-note{{'flag' is 1}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }
@@ -229,6 +257,7 @@ void f(int y) {
 
   if (flag) // expected-note{{'flag' is 1}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }
@@ -252,6 +281,7 @@ void f(int flag) {
 
   if (flag) // expected-note{{'flag' is not equal to 0}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }
@@ -278,6 +308,7 @@ void f(int flag) {
 
   if (flag) // expected-note{{'flag' is not equal to 0}}
             // expected-note@-1{{Taking true branch}}
+            // debug-note@-2{{Tracking condition 'flag'}}
     *x = 5; // expected-warning{{Dereference of null pointer}}
             // expected-note@-1{{Dereference of null pointer}}
 }