Various unwinder work.
Most of the changes are to the FuncUnwinders class -- as we've added
more types of unwind information, the way this class was written was
making it a mess to maintain. Instead of trying to keep one
"non-call site" unwind plan and one "call site" unwind plan, track
all the different types of unwind plans we can possibly retrieve for
each function and have the call-site/non-call-site accessor methods
retrieve those.
Add a real "fast unwind plan" for x86_64 / i386 -- when doing an
unwind through a function, this only has to read the first 4 bytes
to tell if the function has a standard prologue sequence. If so,
we can use the architecture default unwind plan to backtrace
through this function. If we try to retrieve the save location for
other registers later on, a real unwind plan will be used. This
one is just for doing fast backtraces.
Change the compact unwind plan importer to fill in the valid address
range it is valid for.
Compact unwind, in theory, may have multiple entries for a single
function. The FuncUnwinders rewrite includes the start of supporting
this correctly. In practice compact unwind encodings are used for
the entire range of the function today -- in fact, sometimes the same
encoding is used for multiple functions that have the same unwind
rules. But I want to handle a single function that has multiple
different compact unwind UnwindPlans eventually.
llvm-svn: 224689
diff --git a/lldb/source/Symbol/CompactUnwindInfo.cpp b/lldb/source/Symbol/CompactUnwindInfo.cpp
index 09c0ac7..6c8fc5d 100644
--- a/lldb/source/Symbol/CompactUnwindInfo.cpp
+++ b/lldb/source/Symbol/CompactUnwindInfo.cpp
@@ -17,6 +17,7 @@
#include "lldb/Core/Module.h"
#include "lldb/Core/Section.h"
#include "lldb/Core/Section.h"
+#include "lldb/Core/StreamString.h"
#include "lldb/Symbol/CompactUnwindInfo.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/UnwindPlan.h"
@@ -162,6 +163,29 @@
ArchSpec arch;
if (m_objfile.GetArchitecture (arch))
{
+
+ Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
+ if (log && log->GetVerbose())
+ {
+ StreamString strm;
+ addr.Dump (&strm, NULL, Address::DumpStyle::DumpStyleResolvedDescriptionNoFunctionArguments, Address::DumpStyle::DumpStyleFileAddress, arch.GetAddressByteSize());
+ log->Printf ("Got compact unwind encoding 0x%x for function %s", function_info.encoding, strm.GetData());
+ }
+
+ if (function_info.valid_range_offset_start != 0 && function_info.valid_range_offset_end != 0)
+ {
+ SectionList *sl = m_objfile.GetSectionList ();
+ if (sl)
+ {
+ addr_t func_range_start_file_addr =
+ function_info.valid_range_offset_start + m_objfile.GetHeaderAddress().GetFileAddress();
+ AddressRange func_range (func_range_start_file_addr,
+ function_info.valid_range_offset_end - function_info.valid_range_offset_start,
+ sl);
+ unwind_plan.SetPlanValidAddressRange (func_range);
+ }
+ }
+
if (arch.GetTriple().getArch() == llvm::Triple::x86_64)
{
return CreateUnwindPlan_x86_64 (target, function_info, unwind_plan, addr);
@@ -202,6 +226,10 @@
return;
}
+ Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
+ if (log)
+ m_objfile.GetModule()->LogMessage(log, "Reading compact unwind first-level indexes");
+
if (m_unwindinfo_data_computed == false)
{
if (m_section_sp->IsEncrypted())
@@ -341,7 +369,7 @@
}
lldb::offset_t
-CompactUnwindInfo::BinarySearchRegularSecondPage (uint32_t entry_page_offset, uint32_t entry_count, uint32_t function_offset)
+CompactUnwindInfo::BinarySearchRegularSecondPage (uint32_t entry_page_offset, uint32_t entry_count, uint32_t function_offset, uint32_t *entry_func_start_offset, uint32_t *entry_func_end_offset)
{
// typedef uint32_t compact_unwind_encoding_t;
// struct unwind_info_regular_second_level_entry
@@ -369,6 +397,10 @@
{
if (mid == last || (next_func_offset > function_offset))
{
+ if (entry_func_start_offset)
+ *entry_func_start_offset = mid_func_offset;
+ if (mid != last && entry_func_end_offset)
+ *entry_func_end_offset = next_func_offset;
return first_entry + (mid * 8);
}
else
@@ -385,7 +417,7 @@
}
uint32_t
-CompactUnwindInfo::BinarySearchCompressedSecondPage (uint32_t entry_page_offset, uint32_t entry_count, uint32_t function_offset_to_find, uint32_t function_offset_base)
+CompactUnwindInfo::BinarySearchCompressedSecondPage (uint32_t entry_page_offset, uint32_t entry_count, uint32_t function_offset_to_find, uint32_t function_offset_base, uint32_t *entry_func_start_offset, uint32_t *entry_func_end_offset)
{
offset_t first_entry = entry_page_offset;
@@ -411,6 +443,10 @@
{
if (mid == last || (next_func_offset > function_offset_to_find))
{
+ if (entry_func_start_offset)
+ *entry_func_start_offset = mid_func_offset;
+ if (mid != last && entry_func_end_offset)
+ *entry_func_end_offset = next_func_offset;
return UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX (entry);
}
else
@@ -427,7 +463,6 @@
return UINT32_MAX;
}
-
bool
CompactUnwindInfo::GetCompactUnwindInfoForFunction (Target &target, Address address, FunctionInfo &unwind_info)
{
@@ -474,6 +509,15 @@
return false;
}
+ auto next_it = it + 1;
+ if (next_it != m_indexes.begin())
+ {
+ // initialize the function offset end range to be the start of the
+ // next index offset. If we find an entry which is at the end of
+ // the index table, this will establish the range end.
+ unwind_info.valid_range_offset_end = next_it->function_offset;
+ }
+
offset_t second_page_offset = it->second_level;
offset_t lsda_array_start = it->lsda_array_start;
offset_t lsda_array_count = (it->lsda_array_end - it->lsda_array_start) / 8;
@@ -498,7 +542,7 @@
uint16_t entry_page_offset = m_unwindinfo_data.GetU16(&offset); // entryPageOffset
uint16_t entry_count = m_unwindinfo_data.GetU16(&offset); // entryCount
- offset_t entry_offset = BinarySearchRegularSecondPage (second_page_offset + entry_page_offset, entry_count, function_offset);
+ offset_t entry_offset = BinarySearchRegularSecondPage (second_page_offset + entry_page_offset, entry_count, function_offset, &unwind_info.valid_range_offset_start, &unwind_info.valid_range_offset_end);
if (entry_offset == LLDB_INVALID_OFFSET)
{
return false;
@@ -556,7 +600,7 @@
uint16_t encodings_page_offset = m_unwindinfo_data.GetU16(&offset); // encodingsPageOffset
uint16_t encodings_count = m_unwindinfo_data.GetU16(&offset); // encodingsCount
- uint32_t encoding_index = BinarySearchCompressedSecondPage (second_page_offset + entry_page_offset, entry_count, function_offset, it->function_offset);
+ uint32_t encoding_index = BinarySearchCompressedSecondPage (second_page_offset + entry_page_offset, entry_count, function_offset, it->function_offset, &unwind_info.valid_range_offset_start, &unwind_info.valid_range_offset_end);
if (encoding_index == UINT32_MAX || encoding_index >= encodings_count + m_unwind_header.common_encodings_array_count)
{
return false;
@@ -575,7 +619,6 @@
}
if (encoding == 0)
return false;
- unwind_info.encoding = encoding;
unwind_info.encoding = encoding;
if (unwind_info.encoding & UNWIND_HAS_LSDA)