[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

llvm-svn: 364605

Author: nhukc

clang/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;
     }
   }
 

clang/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;
+}