PNaCl dynamic linking: Fix handling of local relocations with addends

lib/Transforms/NaCl/FlattenGlobals.cpp

Index: lib/Transforms/NaCl/FlattenGlobals.cpp
diff --git a/lib/Transforms/NaCl/FlattenGlobals.cpp b/lib/Transforms/NaCl/FlattenGlobals.cpp
index 9b90cb2d4d911cf4835c6ede1b59c965c9df9654..3633be8c363f2fc58f90d80f0db27721116a004c 100644
--- a/lib/Transforms/NaCl/FlattenGlobals.cpp
+++ b/lib/Transforms/NaCl/FlattenGlobals.cpp
@@ -350,13 +350,16 @@ static void ExpandConstant(const DataLayout *DL, Constant *Val,
     *ResultOffset = 0;
   } else if (ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
     *ResultGlobal = NULL;
-    *ResultOffset = CI->getZExtValue();
+    *ResultOffset = CI->getSExtValue();
   } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Val)) {
     ExpandConstant(DL, CE->getOperand(0), ResultGlobal, ResultOffset);
     if (CE->getOpcode() == Instruction::GetElementPtr) {
       SmallVector<Value *, 8> Indexes(CE->op_begin() + 1, CE->op_end());
       *ResultOffset += DL->getIndexedOffset(CE->getOperand(0)->getType(),
                                             Indexes);
+    } else if (CE->getOpcode() == Instruction::Add &&
+               isa<ConstantInt>(CE->getOperand(1))) {
+      *ResultOffset += cast<ConstantInt>(CE->getOperand(1))->getSExtValue();
     } else if (CE->getOpcode() == Instruction::BitCast ||
                CE->getOpcode() == Instruction::IntToPtr) {
       // Nothing more to do.