[RuntimeDyld][MachO] Properly handle thumb to thumb calls within a section.

Previously thumb bits were only checked for external relocations (thumb to arm
code and vice-versa). This patch adds detection for thumb callees in the same
section asthe (also thumb) caller.

The MachO/Thumb test case is updated to cover this, and redundant checks
(handled by the MachO/ARM test) are removed.

llvm-svn: 331838

1 files changed, 19 insertions, 1 deletions

diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h
index 990629de2f1..16a0f6ef2a7 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h
@@ -47,6 +47,18 @@ public:
     return Addr;
   }
 
+  bool isAddrTargetThumb(unsigned SectionID, uint64_t Offset) {
+    auto TargetObjAddr = Sections[SectionID].getObjAddress() + Offset;
+    for (auto &KV : GlobalSymbolTable) {
+      auto &Entry = KV.second;
+      auto SymbolObjAddr =
+          Sections[Entry.getSectionID()].getObjAddress() + Entry.getOffset();
+      if (TargetObjAddr == SymbolObjAddr)
+        return (Entry.getFlags().getTargetFlags() & ARMJITSymbolFlags::Thumb);
+    }
+    return false;
+  }
+
   Expected<int64_t> decodeAddend(const RelocationEntry &RE) const {
     const SectionEntry &Section = Sections[RE.SectionID];
     uint8_t *LocalAddress = Section.getAddressWithOffset(RE.Offset);
@@ -161,12 +173,18 @@ public:
     // the value as being a thumb stub: we don't want to mix it up with an ARM
     // stub targeting the same function.
     if (RE.RelType == MachO::ARM_THUMB_RELOC_BR22)
-      Value.IsStubThumb = TargetIsLocalThumbFunc;
+      Value.IsStubThumb = true;
 
     if (RE.IsPCRel)
       makeValueAddendPCRel(Value, RelI,
                            (RE.RelType == MachO::ARM_THUMB_RELOC_BR22) ? 4 : 8);
 
+    // If this is a non-external branch target check whether Value points to a
+    // thumb func.
+    if (!Value.SymbolName && (RelType == MachO::ARM_RELOC_BR24 ||
+                              RelType == MachO::ARM_THUMB_RELOC_BR22))
+      RE.IsTargetThumbFunc = isAddrTargetThumb(Value.SectionID, Value.Offset);
+
     if (RE.RelType == MachO::ARM_RELOC_BR24 ||
         RE.RelType == MachO::ARM_THUMB_RELOC_BR22)
       processBranchRelocation(RE, Value, Stubs);