Properly sign extend sdata2/4 in unwinder. Patch by Patrick Wildt

llvm-svn: 206122

1 files changed, 4 insertions, 2 deletions

diff --git a/libcxxabi/src/Unwind/AddressSpace.hpp b/libcxxabi/src/Unwind/AddressSpace.hpp
index aac8b7fbd9d..dd58f247156 100644
--- a/libcxxabi/src/Unwind/AddressSpace.hpp
+++ b/libcxxabi/src/Unwind/AddressSpace.hpp
@@ -196,12 +196,14 @@ inline LocalAddressSpace::pint_t LocalAddressSpace::getEncodedP(pint_t &addr,
     result = (pint_t)getSLEB128(addr, end);
     break;
   case DW_EH_PE_sdata2:
-    result = (uint16_t)get16(addr);
+    // Sign extend from signed 16-bit value.
+    result = (int16_t)get16(addr);
     p += 2;
     addr = (pint_t) p;
     break;
   case DW_EH_PE_sdata4:
-    result = (uint32_t)get32(addr);
+    // Sign extend from signed 32-bit value.
+    result = (int32_t)get32(addr);
     p += 4;
     addr = (pint_t) p;
     break;