Files
clang-p2996/lldb/source/Breakpoint/BreakpointSiteList.cpp
Greg Clayton d8cf1a119d Huge performance improvements when one breakpoint contains many locations.
325,000 breakpoints for running "breakpoint set --func-regex ." on lldb itself (after hitting a breakpoint at main so that LLDB.framework is loaded) used to take up to an hour to set, now we are down under a minute. With warm file caches, we are at 40 seconds, and that is with setting 325,000 breakpoint through the GDB remote API. Linux and the native debuggers might be faster. I haven't timed what how much is debug info parsing and how much is the protocol traffic to/from GDB remote.

That there were many performance issues. Most of them were due to storing breakpoints in the wrong data structures, or using the wrong iterators to traverse the lists, traversing the lists in inefficient ways, and not optimizing certain function name lookups/symbol merges correctly.

Debugging after that is also now very efficient. There were issues with replacing the breakpoint opcodes in memory that was read, and those routines were also fixed.

llvm-svn: 183820
2013-06-12 00:46:38 +00:00

241 lines
6.9 KiB
C++

//===-- BreakpointSiteList.cpp ----------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Breakpoint/BreakpointSiteList.h"
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Core/Stream.h"
#include <algorithm>
using namespace lldb;
using namespace lldb_private;
BreakpointSiteList::BreakpointSiteList() :
m_mutex (Mutex::eMutexTypeRecursive),
m_bp_site_list()
{
}
BreakpointSiteList::~BreakpointSiteList()
{
}
// Add breakpoint site to the list. However, if the element already exists in the
// list, then we don't add it, and return LLDB_INVALID_BREAK_ID.
lldb::break_id_t
BreakpointSiteList::Add(const BreakpointSiteSP &bp)
{
lldb::addr_t bp_site_load_addr = bp->GetLoadAddress();
Mutex::Locker locker(m_mutex);
collection::iterator iter = m_bp_site_list.find (bp_site_load_addr);
if (iter == m_bp_site_list.end())
{
m_bp_site_list.insert (iter, collection::value_type (bp_site_load_addr, bp));
return bp->GetID();
}
else
{
return LLDB_INVALID_BREAK_ID;
}
}
bool
BreakpointSiteList::ShouldStop (StoppointCallbackContext *context, lldb::break_id_t site_id)
{
BreakpointSiteSP site_sp (FindByID (site_id));
if (site_sp)
{
// Let the BreakpointSite decide if it should stop here (could not have
// reached it's target hit count yet, or it could have a callback
// that decided it shouldn't stop (shared library loads/unloads).
return site_sp->ShouldStop (context);
}
// We should stop here since this BreakpointSite isn't valid anymore or it
// doesn't exist.
return true;
}
lldb::break_id_t
BreakpointSiteList::FindIDByAddress (lldb::addr_t addr)
{
BreakpointSiteSP bp = FindByAddress (addr);
if (bp)
{
//DBLogIf(PD_LOG_BREAKPOINTS, "BreakpointSiteList::%s ( addr = 0x%8.8" PRIx64 " ) => %u", __FUNCTION__, (uint64_t)addr, bp->GetID());
return bp.get()->GetID();
}
//DBLogIf(PD_LOG_BREAKPOINTS, "BreakpointSiteList::%s ( addr = 0x%8.8" PRIx64 " ) => NONE", __FUNCTION__, (uint64_t)addr);
return LLDB_INVALID_BREAK_ID;
}
bool
BreakpointSiteList::Remove (lldb::break_id_t break_id)
{
Mutex::Locker locker(m_mutex);
collection::iterator pos = GetIDIterator(break_id); // Predicate
if (pos != m_bp_site_list.end())
{
m_bp_site_list.erase(pos);
return true;
}
return false;
}
bool
BreakpointSiteList::RemoveByAddress (lldb::addr_t address)
{
Mutex::Locker locker(m_mutex);
collection::iterator pos = m_bp_site_list.find(address);
if (pos != m_bp_site_list.end())
{
m_bp_site_list.erase(pos);
return true;
}
return false;
}
class BreakpointSiteIDMatches
{
public:
BreakpointSiteIDMatches (lldb::break_id_t break_id) :
m_break_id(break_id)
{
}
bool operator() (std::pair <lldb::addr_t, BreakpointSiteSP> val_pair) const
{
return m_break_id == val_pair.second.get()->GetID();
}
private:
const lldb::break_id_t m_break_id;
};
BreakpointSiteList::collection::iterator
BreakpointSiteList::GetIDIterator (lldb::break_id_t break_id)
{
Mutex::Locker locker(m_mutex);
return std::find_if(m_bp_site_list.begin(), m_bp_site_list.end(), // Search full range
BreakpointSiteIDMatches(break_id)); // Predicate
}
BreakpointSiteList::collection::const_iterator
BreakpointSiteList::GetIDConstIterator (lldb::break_id_t break_id) const
{
Mutex::Locker locker(m_mutex);
return std::find_if(m_bp_site_list.begin(), m_bp_site_list.end(), // Search full range
BreakpointSiteIDMatches(break_id)); // Predicate
}
BreakpointSiteSP
BreakpointSiteList::FindByID (lldb::break_id_t break_id)
{
Mutex::Locker locker(m_mutex);
BreakpointSiteSP stop_sp;
collection::iterator pos = GetIDIterator(break_id);
if (pos != m_bp_site_list.end())
stop_sp = pos->second;
return stop_sp;
}
const BreakpointSiteSP
BreakpointSiteList::FindByID (lldb::break_id_t break_id) const
{
Mutex::Locker locker(m_mutex);
BreakpointSiteSP stop_sp;
collection::const_iterator pos = GetIDConstIterator(break_id);
if (pos != m_bp_site_list.end())
stop_sp = pos->second;
return stop_sp;
}
BreakpointSiteSP
BreakpointSiteList::FindByAddress (lldb::addr_t addr)
{
BreakpointSiteSP found_sp;
Mutex::Locker locker(m_mutex);
collection::iterator iter = m_bp_site_list.find(addr);
if (iter != m_bp_site_list.end())
found_sp = iter->second;
return found_sp;
}
bool
BreakpointSiteList::BreakpointSiteContainsBreakpoint (lldb::break_id_t bp_site_id, lldb::break_id_t bp_id)
{
Mutex::Locker locker(m_mutex);
collection::const_iterator pos = GetIDConstIterator(bp_site_id);
if (pos != m_bp_site_list.end())
return pos->second->IsBreakpointAtThisSite (bp_id);
return false;
}
void
BreakpointSiteList::Dump (Stream *s) const
{
s->Printf("%p: ", this);
//s->Indent();
s->Printf("BreakpointSiteList with %u BreakpointSites:\n", (uint32_t)m_bp_site_list.size());
s->IndentMore();
collection::const_iterator pos;
collection::const_iterator end = m_bp_site_list.end();
for (pos = m_bp_site_list.begin(); pos != end; ++pos)
pos->second.get()->Dump(s);
s->IndentLess();
}
void
BreakpointSiteList::ForEach (std::function <void(BreakpointSite *)> const &callback)
{
Mutex::Locker locker(m_mutex);
for (auto pair : m_bp_site_list)
callback (pair.second.get());
}
bool
BreakpointSiteList::FindInRange (lldb::addr_t lower_bound, lldb::addr_t upper_bound, BreakpointSiteList &bp_site_list) const
{
if (lower_bound > upper_bound)
return false;
Mutex::Locker locker(m_mutex);
collection::const_iterator lower, upper, pos;
lower = m_bp_site_list.lower_bound(lower_bound);
if (lower == m_bp_site_list.end()
|| (*lower).first >= upper_bound)
return false;
// This is one tricky bit. The breakpoint might overlap the bottom end of the range. So we grab the
// breakpoint prior to the lower bound, and check that that + its byte size isn't in our range.
if (lower != m_bp_site_list.begin())
{
collection::const_iterator prev_pos = lower;
prev_pos--;
const BreakpointSiteSP &prev_bp = (*prev_pos).second;
if (prev_bp->GetLoadAddress() + prev_bp->GetByteSize() > lower_bound)
bp_site_list.Add (prev_bp);
}
upper = m_bp_site_list.upper_bound(upper_bound);
for (pos = lower; pos != upper; pos++)
{
bp_site_list.Add ((*pos).second);
}
return true;
}