[libcxx-commits] [PATCH] D86748: [libunwind] Bare-metal DWARF: set dso_base to 0

[Ryan Prichard via Phabricator via libcxx-commits]

rprichard updated this revision to Diff 290630.
rprichard added a comment.

Use -1 to indicate "search all cache entries".


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D86748/new/

https://reviews.llvm.org/D86748

Files:
  libunwind/src/AddressSpace.hpp
  libunwind/src/UnwindCursor.hpp


Index: libunwind/src/UnwindCursor.hpp
===================================================================
--- libunwind/src/UnwindCursor.hpp
+++ libunwind/src/UnwindCursor.hpp
@@ -81,6 +81,7 @@
 class _LIBUNWIND_HIDDEN DwarfFDECache {
   typedef typename A::pint_t pint_t;
 public:
+  static const pint_t kSearchAll = static_cast<pint_t>(-1);
   static pint_t findFDE(pint_t mh, pint_t pc);
   static void add(pint_t mh, pint_t ip_start, pint_t ip_end, pint_t fde);
   static void removeAllIn(pint_t mh);
@@ -138,7 +139,7 @@
   pint_t result = 0;
   _LIBUNWIND_LOG_IF_FALSE(_lock.lock_shared());
   for (entry *p = _buffer; p < _bufferUsed; ++p) {
-    if ((mh == p->mh) || (mh == 0)) {
+    if ((mh == p->mh) || (mh == kSearchAll)) {
       if ((p->ip_start <= pc) && (pc < p->ip_end)) {
         result = p->fde;
         break;
@@ -1945,7 +1946,8 @@
 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
   // There is no static unwind info for this pc. Look to see if an FDE was
   // dynamically registered for it.
-  pint_t cachedFDE = DwarfFDECache<A>::findFDE(0, pc);
+  pint_t cachedFDE = DwarfFDECache<A>::findFDE(DwarfFDECache<A>::kSearchAll,
+                                               pc);
   if (cachedFDE != 0) {
     typename CFI_Parser<A>::FDE_Info fdeInfo;
     typename CFI_Parser<A>::CIE_Info cieInfo;
Index: libunwind/src/AddressSpace.hpp
===================================================================
--- libunwind/src/AddressSpace.hpp
+++ libunwind/src/AddressSpace.hpp
@@ -518,6 +518,7 @@
     return true;
   }
 #elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_LIBUNWIND_IS_BAREMETAL)
+  info.dso_base = 0;
   // Bare metal is statically linked, so no need to ask the dynamic loader
   info.dwarf_section_length = (uintptr_t)(&__eh_frame_end - &__eh_frame_start);
   info.dwarf_section =        (uintptr_t)(&__eh_frame_start);


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