[lldb] Call os_log_fault on lldb_assert

[JDevlieghere]

Summary

Call os_log_fault when an lldb assert fails. We piggyback off of the LLVM_SUPPORT_XCODE_SIGNPOSTS to for os_log support rather than introducing another check and define just for this. This patch also adds a small test using lldb-test.

lldb/include/lldb/Utility/LLDBAssert.h

 #define lldbassert(x)                                                          \
   lldb_private::lldb_assert(static_cast<bool>(x), #x, __FUNCTION__, __FILE__,  \
                             __LINE__)
 #endif
 
 namespace lldb_private {
 void lldb_assert(bool expression, const char *expr_text, const char *func,
                  const char *file, unsigned int line);
-}
+} // namespace lldb_private
 
 #endif // LLDB_UTILITY_LLDBASSERT_H

lldb/source/Utility/LLDBAssert.cpp

 //===-- LLDBAssert.cpp ----------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "lldb/Utility/LLDBAssert.h"
-
+#include "llvm/Config/config.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/raw_ostream.h"
 
+#if LLVM_SUPPORT_XCODE_SIGNPOSTS
+#include <os/log.h>
+#endif
+
 using namespace llvm;
 using namespace lldb_private;
 
 void lldb_private::lldb_assert(bool expression, const char *expr_text,
                                const char *func, const char *file,
                                unsigned int line) {
   if (LLVM_LIKELY(expression))
     return;
 
+#if LLVM_SUPPORT_XCODE_SIGNPOSTS
+  if (__builtin_available(macos 10.12, iOS 10, tvOS 10, watchOS 3, *)) {
+    os_log_fault(OS_LOG_DEFAULT,
+                 "Assertion failed: (%s), function %s, file %s, line %u\n",
+                 expr_text, func, file, line);
+  }
+#endif
+
   // If asserts are enabled abort here.
   assert(false && "lldb_assert failed");
 
   // In a release configuration it will print a warning and encourage the user
   // to file a bug report, similar to LLVM’s crash handler, and then return
   // execution.
   errs() << format("Assertion failed: (%s), function %s, file %s, line %u\n",
                    expr_text, func, file, line);
   errs() << "backtrace leading to the failure:\n";
   llvm::sys::PrintStackTrace(errs());
   errs() << "please file a bug report against lldb reporting this failure "
             "log, and as many details as possible\n";
 }

lldb/test/Shell/Error/assert.test

+# REQUIRES: asserts
+# RUN: not --crash lldb-test assert > %t.error 2>&1
+# RUN: cat %t.error | FileCheck %s
+# CHECK: Assertion failed: (false && "lldb_assert failed")

lldb/tools/lldb-test/lldb-test.cpp

 #include "lldb/Symbol/SymbolFile.h"
 #include "lldb/Symbol/TypeList.h"
 #include "lldb/Symbol/TypeMap.h"
 #include "lldb/Symbol/VariableList.h"
 #include "lldb/Target/Language.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/Target.h"
 #include "lldb/Utility/DataExtractor.h"
+#include "lldb/Utility/LLDBAssert.h"
 #include "lldb/Utility/State.h"
 #include "lldb/Utility/StreamString.h"
 
 #include "llvm/ADT/IntervalMap.h"
 #include "llvm/ADT/ScopeExit.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ManagedStatic.h"

 
 namespace opts {
 static cl::SubCommand BreakpointSubcommand("breakpoints",
                                            "Test breakpoint resolution");
 cl::SubCommand ObjectFileSubcommand("object-file",
                                     "Display LLDB object file information");
 cl::SubCommand SymbolsSubcommand("symbols", "Dump symbols for an object file");
 cl::SubCommand IRMemoryMapSubcommand("ir-memory-map", "Test IRMemoryMap");
+cl::SubCommand AssertSubcommand("assert", "Test assert handling");
 
 cl::opt<std::string> Log("log", cl::desc("Path to a log file"), cl::init(""),
                          cl::sub(BreakpointSubcommand),
                          cl::sub(ObjectFileSubcommand),
                          cl::sub(SymbolsSubcommand),
                          cl::sub(IRMemoryMapSubcommand));
 
 /// Create a target using the file pointed to by \p Filename, or abort.
IRMemoryMapTestState(TargetSP Target)
       : Target(Target), Map(Target), Allocations(IntervalMapAllocator) {}
 };
 
 bool evalMalloc(StringRef Line, IRMemoryMapTestState &State);
 bool evalFree(StringRef Line, IRMemoryMapTestState &State);
 int evaluateMemoryMapCommands(Debugger &Dbg);
 } // namespace irmemorymap
 
+namespace assert {
+int lldb_assert(Debugger &Dbg);
+} // namespace assert
 } // namespace opts
 
 std::vector<CompilerContext> parseCompilerContext() {
   std::vector<CompilerContext> result;
   if (opts::symbols::CompilerContext.empty())
     return result;
 
   StringRef str{opts::symbols::CompilerContext};
if (evalFree(Line, State))
       continue;
 
     errs() << "Could not parse line: " << Line << "\n";
     exit(1);
   }
   return 0;
 }
 
+int opts::assert::lldb_assert(Debugger &Dbg) {
+  lldbassert(false && "lldb-test assert");
+  return 1;
+}
+
 int main(int argc, const char *argv[]) {
   StringRef ToolName = argv[0];
   sys::PrintStackTraceOnErrorSignal(ToolName);
   PrettyStackTraceProgram X(argc, argv);
   llvm_shutdown_obj Y;
 
   cl::ParseCommandLineOptions(argc, argv, "LLDB Testing Utility\n");
 
int main(int argc, const char *argv[]) {
   if (opts::BreakpointSubcommand)
     return opts::breakpoint::evaluateBreakpoints(*Dbg);
   if (opts::ObjectFileSubcommand)
     return dumpObjectFiles(*Dbg);
   if (opts::SymbolsSubcommand)
     return opts::symbols::dumpSymbols(*Dbg);
   if (opts::IRMemoryMapSubcommand)
     return opts::irmemorymap::evaluateMemoryMapCommands(*Dbg);
+  if (opts::AssertSubcommand)
+    return opts::assert::lldb_assert(*Dbg);
 
   WithColor::error() << "No command specified.\n";
   return 1;
 }