Add RSB instruction to the ARM integrated assembler.

src/IceInstARM32.cpp

Index: src/IceInstARM32.cpp
diff --git a/src/IceInstARM32.cpp b/src/IceInstARM32.cpp
index c7adce8bc5ed1a43651ba31a6ae117cdc08f9040..6932d2f9d01ba502c906ec2e7425c2b60aaeda5a 100644
--- a/src/IceInstARM32.cpp
+++ b/src/IceInstARM32.cpp
@@ -506,6 +506,13 @@ template <> void InstARM32Mul::emitIAS(const Cfg *Func) const {
     emitUsingTextFixup(Func);
 }
 
+template <> void InstARM32Rsb::emitIAS(const Cfg *Func) const {
+  auto *Asm = Func->getAssembler<ARM32::AssemblerARM32>();
+  Asm->rsb(getDest(), getSrc(0), getSrc(1), SetFlags, getPredicate());
+  if (Asm->needsTextFixup())
+    emitUsingTextFixup(Func);
+}
+
 template <> void InstARM32Sbc::emitIAS(const Cfg *Func) const {
   auto *Asm = Func->getAssembler<ARM32::AssemblerARM32>();
   Asm->sbc(getDest(), getSrc(0), getSrc(1), SetFlags, getPredicate());