InstrProf: Don't extend coverage regions into the catch keyword

The catch keyword isn't really part of a region, so it's fairly
meaningless to extend into it. This was usually harmless, but it could
crash when catch blocks involved macros in strange ways.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@243066 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CoverageMappingGen.cpp

@@ -842,7 +842,6 @@ struct CounterCoverageMappingBuilder
   }
 
   void VisitCXXCatchStmt(const CXXCatchStmt *S) {
-    extendRegion(S);
     propagateCounts(getRegionCounter(S), S->getHandlerBlock());
   }
 

test/CoverageMapping/trymacro.cpp

+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++11 -fexceptions -fcxx-exceptions -fprofile-instr-generate -fcoverage-mapping -dump-coverage-mapping -emit-llvm-only -main-file-name trymacro.cpp %s | FileCheck %s
+
+// CHECK: Z3fn1v:
+void fn1() try { return; } // CHECK: [[@LINE]]:12 -> [[@LINE+1]]:14 = #1
+catch(...) {}              // CHECK: [[@LINE]]:12 -> [[@LINE]]:14 = #2
+
+#define RETURN_BLOCK { return; }
+
+// CHECK: Z3fn2v:
+void fn2() try RETURN_BLOCK // CHECK: [[@LINE]]:12 -> [[@LINE+1]]:14 = #1
+catch(...) {}               // CHECK: [[@LINE]]:12 -> [[@LINE]]:14 = #2
+
+#define TRY try
+#define CATCH(x) catch (x)
+
+// CHECK: Z3fn3v:
+void fn3() TRY { return; } // CHECK: [[@LINE]]:12 -> [[@LINE+1]]:14 = #1
+CATCH(...) {}              // CHECK: [[@LINE]]:12 -> [[@LINE]]:14 = #2
+
+int main() {
+  fn1();
+  fn2();
+  fn3();
+}