From 0dd62ace2ee2fafcb9a08953db1b9e4e20428e28 Mon Sep 17 00:00:00 2001 From: Med Ismail Bennani Date: Wed, 7 Jun 2023 16:51:45 -0700 Subject: [lldb] Disable variable watchpoints when going out of scope If we use a variable watchpoint with a condition using a scope variable, if we go out-of-scope, the watpoint remains active which can the expression evaluator to fail to parse the watchpoint condition (because of the missing varible bindings). This was discovered after `watchpoint_callback.test` started failing on the green dragon bot. This patch should address that issue by setting an internal breakpoint on the return addresss of the current frame when creating a variable watchpoint. The breakpoint has a callback that will disable the watchpoint if the the breakpoint execution context matches the watchpoint execution context. This is only enabled for local variables. This patch also re-enables the failing test following e1086384e584. rdar://109574319 Differential Revision: https://reviews.llvm.org/D151366 Signed-off-by: Med Ismail Bennani --- lldb/source/Commands/CommandObjectWatchpoint.cpp | 37 ++++++++++++++---------- 1 file changed, 22 insertions(+), 15 deletions(-) (limited to 'lldb/source/Commands/CommandObjectWatchpoint.cpp') diff --git a/lldb/source/Commands/CommandObjectWatchpoint.cpp b/lldb/source/Commands/CommandObjectWatchpoint.cpp index b73c9a2..a4929ea 100644 --- a/lldb/source/Commands/CommandObjectWatchpoint.cpp +++ b/lldb/source/Commands/CommandObjectWatchpoint.cpp @@ -9,6 +9,7 @@ #include "CommandObjectWatchpoint.h" #include "CommandObjectWatchpointCommand.h" +#include #include #include "llvm/ADT/StringRef.h" @@ -20,6 +21,7 @@ #include "lldb/Interpreter/CommandInterpreter.h" #include "lldb/Interpreter/CommandOptionArgumentTable.h" #include "lldb/Interpreter/CommandReturnObject.h" +#include "lldb/Symbol/Function.h" #include "lldb/Symbol/Variable.h" #include "lldb/Symbol/VariableList.h" #include "lldb/Target/StackFrame.h" @@ -950,27 +952,32 @@ protected: error.Clear(); WatchpointSP watch_sp = target->CreateWatchpoint(addr, size, &compiler_type, watch_type, error); - if (watch_sp) { - watch_sp->SetWatchSpec(command.GetArgumentAtIndex(0)); - watch_sp->SetWatchVariable(true); - if (var_sp && var_sp->GetDeclaration().GetFile()) { + if (!watch_sp) { + result.AppendErrorWithFormat( + "Watchpoint creation failed (addr=0x%" PRIx64 ", size=%" PRIu64 + ", variable expression='%s').\n", + addr, static_cast(size), command.GetArgumentAtIndex(0)); + if (const char *error_message = error.AsCString(nullptr)) + result.AppendError(error_message); + return result.Succeeded(); + } + + watch_sp->SetWatchSpec(command.GetArgumentAtIndex(0)); + watch_sp->SetWatchVariable(true); + if (var_sp) { + if (var_sp->GetDeclaration().GetFile()) { StreamString ss; // True to show fullpath for declaration file. var_sp->GetDeclaration().DumpStopContext(&ss, true); watch_sp->SetDeclInfo(std::string(ss.GetString())); } - output_stream.Printf("Watchpoint created: "); - watch_sp->GetDescription(&output_stream, lldb::eDescriptionLevelFull); - output_stream.EOL(); - result.SetStatus(eReturnStatusSuccessFinishResult); - } else { - result.AppendErrorWithFormat( - "Watchpoint creation failed (addr=0x%" PRIx64 ", size=%" PRIu64 - ", variable expression='%s').\n", - addr, (uint64_t)size, command.GetArgumentAtIndex(0)); - if (error.AsCString(nullptr)) - result.AppendError(error.AsCString()); + if (var_sp->GetScope() == eValueTypeVariableLocal) + watch_sp->SetupVariableWatchpointDisabler(m_exe_ctx.GetFrameSP()); } + output_stream.Printf("Watchpoint created: "); + watch_sp->GetDescription(&output_stream, lldb::eDescriptionLevelFull); + output_stream.EOL(); + result.SetStatus(eReturnStatusSuccessFinishResult); return result.Succeeded(); } -- cgit v1.1