From: David Blaikie <dblaikie@gmail.com>
Date: Sat, 22 Dec 2018 22:20:40 +0000 (+0000)
Subject: DebugInfo: Accurately propagate the section used by a relocation when accessing range... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e9c8ee7d5360774895ef41c222c7a6d924e5bb8e;p=llvm

DebugInfo: Accurately propagate the section used by a relocation when accessing ranges defined by low/high_pc

This is difficult/not possible to test in LLVM, but is visible as a
crash in LLD when parsing DWARF to generate gdb-index.

This function is called by llvm-dwarfdump when parsing high_pc for
non-verbose output (to print the actual high_pc rather than the low_pc
relative value), but in that case llvm-dwarfdump doesn't print section
names (if it did, it would hit this problem).

We could add some other features to llvm-dwarfdump to expose this, but
nothing really springs to my mind. I will add a test to lld, though.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350010 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/DebugInfo/DWARF/DWARFFormValue.h b/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
index ed34d3c21de..727e853c09f 100644
--- a/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
+++ b/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
@@ -61,7 +61,6 @@ public:
 
   dwarf::Form getForm() const { return Form; }
   uint64_t getRawUValue() const { return Value.uval; }
-  uint64_t getSectionIndex() const { return Value.SectionIndex; }
   void setForm(dwarf::Form F) { Form = F; }
   void setUValue(uint64_t V) { Value.uval = V; }
   void setSValue(int64_t V) { Value.sval = V; }
diff --git a/lib/DebugInfo/DWARF/DWARFDie.cpp b/lib/DebugInfo/DWARF/DWARFDie.cpp
index fd692ab519c..81ef0c8c7ae 100644
--- a/lib/DebugInfo/DWARF/DWARFDie.cpp
+++ b/lib/DebugInfo/DWARF/DWARFDie.cpp
@@ -466,13 +466,13 @@ Optional<uint64_t> DWARFDie::getHighPC(uint64_t LowPC) const {
 bool DWARFDie::getLowAndHighPC(uint64_t &LowPC, uint64_t &HighPC,
                                uint64_t &SectionIndex) const {
   auto F = find(DW_AT_low_pc);
-  auto LowPcAddr = toAddress(F);
+  auto LowPcAddr = toSectionedAddress(F);
   if (!LowPcAddr)
     return false;
-  if (auto HighPcAddr = getHighPC(*LowPcAddr)) {
-    LowPC = *LowPcAddr;
+  if (auto HighPcAddr = getHighPC(LowPcAddr->Address)) {
+    LowPC = LowPcAddr->Address;
     HighPC = *HighPcAddr;
-    SectionIndex = F->getSectionIndex();
+    SectionIndex = LowPcAddr->SectionIndex;
     return true;
   }
   return false;