The Platform base class now maintains a list of trap handlers
aka asynchronous signal handlers, which subclasses should fill
in as appropriate. For most Unix user process environments,
the one entry in this list is _sigtramp. For bare-board and
kernel environments, there will be different sets of trap
handlers.
The unwinder needs to know when a frame is a trap handler
because the rules it enforces for the frame "above" the
trap handler is different from most middle-of-the-stack frames.
<rdar://problem/15835846>
llvm-svn: 201300
diff --git a/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.cpp b/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.cpp
index 954bf7b..3f4c660 100644
--- a/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.cpp
+++ b/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.cpp
@@ -21,16 +21,17 @@
#include "lldb/Symbol/FuncUnwinders.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/ObjectFile.h"
-#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Symbol/Symbol.h"
+#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Target/ABI.h"
+#include "lldb/Target/DynamicLoader.h"
#include "lldb/Target/ExecutionContext.h"
+#include "lldb/Target/Platform.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/SectionLoadList.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
-#include "lldb/Target/DynamicLoader.h"
#include "RegisterContextLLDB.h"
@@ -76,7 +77,7 @@
// This same code exists over in the GetFullUnwindPlanForFrame() but it may not have been executed yet
if (IsFrameZero()
- || next_frame->m_frame_type == eSigtrampFrame
+ || next_frame->m_frame_type == eTrapHandlerFrame
|| next_frame->m_frame_type == eDebuggerFrame)
{
m_all_registers_available = true;
@@ -171,17 +172,21 @@
AddressRange addr_range;
m_sym_ctx.GetAddressRange (eSymbolContextFunction | eSymbolContextSymbol, 0, false, addr_range);
- static ConstString g_sigtramp_name ("_sigtramp");
- if ((m_sym_ctx.function && m_sym_ctx.function->GetName() == g_sigtramp_name) ||
- (m_sym_ctx.symbol && m_sym_ctx.symbol->GetName() == g_sigtramp_name))
+ m_frame_type = eNormalFrame;
+ PlatformSP platform_sp (process->GetTarget().GetPlatform());
+ if (platform_sp)
{
- m_frame_type = eSigtrampFrame;
+ const std::vector<ConstString> trap_handler_names (platform_sp->GetTrapHandlerSymbolNames());
+ for (ConstString name : trap_handler_names)
+ {
+ if ((m_sym_ctx.function && m_sym_ctx.function->GetName() == name) ||
+ (m_sym_ctx.symbol && m_sym_ctx.symbol->GetName() == name))
+ {
+ m_frame_type = eTrapHandlerFrame;
+ }
+ }
}
- else
- {
- // FIXME: Detect eDebuggerFrame here.
- m_frame_type = eNormalFrame;
- }
+ // FIXME: Detect eDebuggerFrame here.
// If we were able to find a symbol/function, set addr_range to the bounds of that symbol/function.
// else treat the current pc value as the start_pc and record no offset.
@@ -442,7 +447,7 @@
// Or if we're in the middle of the stack (and not "above" an asynchronous event like sigtramp),
// and our "current" pc is the start of a function...
if (m_sym_ctx_valid
- && GetNextFrame()->m_frame_type != eSigtrampFrame
+ && GetNextFrame()->m_frame_type != eTrapHandlerFrame
&& GetNextFrame()->m_frame_type != eDebuggerFrame
&& addr_range.GetBaseAddress().IsValid()
&& addr_range.GetBaseAddress().GetSection() == m_current_pc.GetSection()
@@ -492,20 +497,25 @@
m_current_offset_backed_up_one = -1;
}
- static ConstString sigtramp_name ("_sigtramp");
- if ((m_sym_ctx.function && m_sym_ctx.function->GetMangled().GetMangledName() == sigtramp_name)
- || (m_sym_ctx.symbol && m_sym_ctx.symbol->GetMangled().GetMangledName() == sigtramp_name))
+ if (m_frame_type != eSkipFrame) // don't override eSkipFrame
{
- m_frame_type = eSigtrampFrame;
+ m_frame_type = eNormalFrame;
}
- else
+ PlatformSP platform_sp (process->GetTarget().GetPlatform());
+ if (platform_sp)
{
- // FIXME: Detect eDebuggerFrame here.
- if (m_frame_type != eSkipFrame) // don't override eSkipFrame
+ const std::vector<ConstString> trap_handler_names (platform_sp->GetTrapHandlerSymbolNames());
+ for (ConstString name : trap_handler_names)
{
- m_frame_type = eNormalFrame;
+ if ((m_sym_ctx.function && m_sym_ctx.function->GetName() == name) ||
+ (m_sym_ctx.symbol && m_sym_ctx.symbol->GetName() == name))
+ {
+ m_frame_type = eTrapHandlerFrame;
+ }
}
}
+ // FIXME: Detect eDebuggerFrame here.
+
// We've set m_frame_type and m_sym_ctx before this call.
m_fast_unwind_plan_sp = GetFastUnwindPlanForFrame ();
@@ -617,7 +627,7 @@
//
// On entry to this method,
//
-// 1. m_frame_type should already be set to eSigtrampFrame/eDebuggerFrame if either of those are correct,
+// 1. m_frame_type should already be set to eTrapHandlerFrame/eDebuggerFrame if either of those are correct,
// 2. m_sym_ctx should already be filled in, and
// 3. m_current_pc should have the current pc value for this frame
// 4. m_current_offset_backed_up_one should have the current byte offset into the function, maybe backed up by 1, -1 if unknown
@@ -639,7 +649,7 @@
return unwind_plan_sp;
// If we're in _sigtramp(), unwinding past this frame requires special knowledge.
- if (m_frame_type == eSigtrampFrame || m_frame_type == eDebuggerFrame)
+ if (m_frame_type == eTrapHandlerFrame || m_frame_type == eDebuggerFrame)
return unwind_plan_sp;
unwind_plan_sp = func_unwinders_sp->GetUnwindPlanFastUnwind (m_thread);
@@ -668,7 +678,7 @@
// On entry to this method,
//
-// 1. m_frame_type should already be set to eSigtrampFrame/eDebuggerFrame if either of those are correct,
+// 1. m_frame_type should already be set to eTrapHandlerFrame/eDebuggerFrame if either of those are correct,
// 2. m_sym_ctx should already be filled in, and
// 3. m_current_pc should have the current pc value for this frame
// 4. m_current_offset_backed_up_one should have the current byte offset into the function, maybe backed up by 1, -1 if unknown
@@ -693,7 +703,7 @@
bool behaves_like_zeroth_frame = false;
if (IsFrameZero ()
- || GetNextFrame()->m_frame_type == eSigtrampFrame
+ || GetNextFrame()->m_frame_type == eTrapHandlerFrame
|| GetNextFrame()->m_frame_type == eDebuggerFrame)
{
behaves_like_zeroth_frame = true;
@@ -763,7 +773,7 @@
// is properly encoded in the eh_frame section, so prefer that if available.
// On other platforms we may need to provide a platform-specific UnwindPlan which encodes the details of
// how to unwind out of sigtramp.
- if (m_frame_type == eSigtrampFrame)
+ if (m_frame_type == eTrapHandlerFrame)
{
m_fast_unwind_plan_sp.reset();
unwind_plan_sp = func_unwinders_sp->GetUnwindPlanAtCallSite (m_current_offset_backed_up_one);
@@ -983,9 +993,9 @@
}
bool
-RegisterContextLLDB::IsSigtrampFrame () const
+RegisterContextLLDB::IsTrapHandlerFrame () const
{
- return m_frame_type == eSigtrampFrame;
+ return m_frame_type == eTrapHandlerFrame;
}
// A skip frame is a bogus frame on the stack -- but one where we're likely to find a real frame farther
diff --git a/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.h b/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.h
index 1479787..5054572 100644
--- a/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.h
+++ b/lldb/source/Plugins/Process/Utility/RegisterContextLLDB.h
@@ -73,7 +73,7 @@
IsValid () const;
bool
- IsSigtrampFrame () const;
+ IsTrapHandlerFrame () const;
bool
GetCFA (lldb::addr_t& cfa);
@@ -89,7 +89,7 @@
enum FrameType
{
eNormalFrame,
- eSigtrampFrame,
+ eTrapHandlerFrame,
eDebuggerFrame, // a debugger inferior function call frame; we get caller's registers from debugger
eSkipFrame, // The unwind resulted in a bogus frame but may get back on track so we don't want to give up yet
eNotAValidFrame // this frame is invalid for some reason - most likely it is past the top (end) of the stack
diff --git a/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp b/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
index ddded5a..36223db 100644
--- a/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
+++ b/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
@@ -174,7 +174,7 @@
// On Mac OS X, the _sigtramp asynchronous signal trampoline frame may not have
// its (constructed) CFA aligned correctly -- don't do the abi alignment check for
// these.
- if (reg_ctx_sp->IsSigtrampFrame() == false)
+ if (reg_ctx_sp->IsTrapHandlerFrame() == false)
{
if (log)
{