From 75e55592872521950262293d9c3a96d497b2c42e Mon Sep 17 00:00:00 2001
From: Nathan Huckleberry <nhuck@google.com>
Date: Thu, 27 Jun 2019 22:46:40 +0000
Subject: [PATCH] [analyzer] Fix clang-tidy crash on GCCAsmStmt

Summary:
Added entry in switch statement to recognize GCCAsmStmt
as a possible block terminator.

Handling to build CFG using GCCAsmStmt was already implemented.

Reviewers: nickdesaulniers, george.karpenkov, NoQ

Reviewed By: nickdesaulniers, NoQ

Subscribers: xbolva00, tmroeder, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63533

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@364605 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/StaticAnalyzer/Core/CoreEngine.cpp     |  5 +++++
 test/Analysis/egraph-asm-goto-no-crash.cpp | 26 ++++++++++++++++++++++
 2 files changed, 31 insertions(+)
 create mode 100644 test/Analysis/egraph-asm-goto-no-crash.cpp

diff --git a/lib/StaticAnalyzer/Core/CoreEngine.cpp b/lib/StaticAnalyzer/Core/CoreEngine.cpp
index 431d07dab1..94cf74de82 100644
--- a/lib/StaticAnalyzer/Core/CoreEngine.cpp
+++ b/lib/StaticAnalyzer/Core/CoreEngine.cpp
@@ -396,6 +396,11 @@ void CoreEngine::HandleBlockExit(const CFGBlock * B, ExplodedNode *Pred) {
       case Stmt::WhileStmtClass:
         HandleBranch(cast<WhileStmt>(Term)->getCond(), Term, B, Pred);
         return;
+
+      case Stmt::GCCAsmStmtClass:
+        assert(cast<GCCAsmStmt>(Term)->isAsmGoto() && "Encountered GCCAsmStmt without labels");
+        // TODO: Handle jumping to labels
+        return;
     }
   }
 
diff --git a/test/Analysis/egraph-asm-goto-no-crash.cpp b/test/Analysis/egraph-asm-goto-no-crash.cpp
new file mode 100644
index 0000000000..37f8fc533a
--- /dev/null
+++ b/test/Analysis/egraph-asm-goto-no-crash.cpp
@@ -0,0 +1,26 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -verify %s
+
+// expected-no-diagnostics
+
+void clang_analyzer_warnIfReached();
+
+void testAsmGoto() {
+  asm goto("xor %0, %0\n je %l[label1]\n jl %l[label2]"
+           : /* no outputs */
+           : /* inputs */
+           : /* clobbers */
+           : label1, label2 /* any labels used */);
+
+  // FIXME: Should be reachable.
+  clang_analyzer_warnIfReached();
+
+  label1:
+  // FIXME: Should be reachable.
+  clang_analyzer_warnIfReached();
+  return;
+
+  label2:
+  // FIXME: Should be reachable.
+  clang_analyzer_warnIfReached();
+  return;
+}
-- 
2.40.0