Fix PR4687. Pre ARMv5te does not support ldrd / strd. Patch by John Tytgat.

llvm-svn: 83058
diff --git a/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index f1a6c64..031f5b0 100644
--- a/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -1191,6 +1191,10 @@
                                           unsigned &PredReg,
                                           ARMCC::CondCodes &Pred,
                                           bool &isT2) {
+  // Make sure we're allowed to generate LDRD/STRD.
+  if (!STI->hasV5TEOps())
+    return false;
+
   // FIXME: FLDS / FSTS -> FLDD / FSTD
   unsigned Scale = 1;
   unsigned Opcode = Op0->getOpcode();