Fix backtrace of noreturn functions situated at the end of a module

Summary:
When a call instruction is the last instruction in a function, the
backtrace PC will point past the end of the function. We already had
special code to handle that, but we did not handle the case where the PC
ends up outside of the bounds of the module containing the function,
which is a situation that occured in TestNoreturnUnwind on android for
some arch/compiler combinations.

I fix this by adding an argument to Address resolution code which states
that we are ok with addresses pointing to the end of a module/section to
resolve to that module/section.

I create a reproducible test case for this situation by hand-crafting an
executable which has a noreturn function at the end of a module.

Reviewers: jasonmolenda, jingham

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D32022

llvm-svn: 304976

1 files changed, 11 insertions, 11 deletions

diff --git a/lldb/source/Core/Section.cpp b/lldb/source/Core/Section.cpp
index f6428ced016..3b76dd361ff 100644
--- a/lldb/source/Core/Section.cpp
+++ b/lldb/source/Core/Section.cpp
@@ -220,18 +220,18 @@ addr_t Section::GetLoadBaseAddress(Target *target) const {
   return load_base_addr;
 }
 
-bool Section::ResolveContainedAddress(addr_t offset, Address &so_addr) const {
+bool Section::ResolveContainedAddress(addr_t offset, Address &so_addr,
+                                      bool allow_section_end) const {
   const size_t num_children = m_children.GetSize();
-  if (num_children > 0) {
-    for (size_t i = 0; i < num_children; i++) {
-      Section *child_section = m_children.GetSectionAtIndex(i).get();
-
-      addr_t child_offset = child_section->GetOffset();
-      if (child_offset <= offset &&
-          offset - child_offset < child_section->GetByteSize())
-        return child_section->ResolveContainedAddress(offset - child_offset,
-                                                      so_addr);
-    }
+  for (size_t i = 0; i < num_children; i++) {
+    Section *child_section = m_children.GetSectionAtIndex(i).get();
+
+    addr_t child_offset = child_section->GetOffset();
+    if (child_offset <= offset &&
+        offset - child_offset <
+            child_section->GetByteSize() + (allow_section_end ? 1 : 0))
+      return child_section->ResolveContainedAddress(offset - child_offset,
+                                                    so_addr, allow_section_end);
   }
   so_addr.SetOffset(offset);
   so_addr.SetSection(const_cast<Section *>(this)->shared_from_this());