Add ldrex and strex instructions to ARM assembler/disassmbler

src/arm/assembler-arm.h

Index: src/arm/assembler-arm.h
diff --git a/src/arm/assembler-arm.h b/src/arm/assembler-arm.h
index 26e062bdf6af3262372a00d1467c1c8adf49eca0..8f014747ff52a452a75cb4fd84df49014b22d3c6 100644
--- a/src/arm/assembler-arm.h
+++ b/src/arm/assembler-arm.h
@@ -986,6 +986,14 @@ class Assembler : public AssemblerBase {
             Register src2,
             const MemOperand& dst, Condition cond = al);
 
+  // Load/Store exclusive instructions
+  void ldrex(Register dst, Register src, Condition cond = al);
+  void strex(Register src1, Register src2, Register dst, Condition cond = al);
+  void ldrexb(Register dst, Register src, Condition cond = al);
+  void strexb(Register src1, Register src2, Register dst, Condition cond = al);
+  void ldrexh(Register dst, Register src, Condition cond = al);
+  void strexh(Register src1, Register src2, Register dst, Condition cond = al);
+
   // Preload instructions
   void pld(const MemOperand& address);