Mark some singlestep flag functions const.

Author: khuey

src/Registers.cc

@@ -659,7 +659,7 @@ void Registers::set_from_trace(SupportedArch a, const void* data,
   memcpy(&u.arm64regs, data, sizeof(u.arm64regs));
 }
 
-bool Registers::aarch64_singlestep_flag() {
+bool Registers::aarch64_singlestep_flag() const {
   switch (arch()) {
     case aarch64:
       return pstate() & AARCH64_DBG_SPSR_SS;
@@ -679,7 +679,7 @@ void Registers::set_aarch64_singlestep_flag() {
   }
 }
 
-bool Registers::x86_singlestep_flag() {
+bool Registers::x86_singlestep_flag() const {
   switch (arch()) {
     case x86:
     case x86_64:

src/Registers.h

@@ -424,7 +424,7 @@ class Registers {
    * Modify the processor's single step flag. On x86 this is the TF flag in the
    * eflags register.
    */
-  bool x86_singlestep_flag();
+  bool x86_singlestep_flag() const;
   void clear_x86_singlestep_flag();
 
   /**
@@ -441,7 +441,7 @@ class Registers {
    * likely already be clear, and we'd take a single step exception without
    * ever having executed any userspace instructions whatsoever.
    */
-  bool aarch64_singlestep_flag();
+  bool aarch64_singlestep_flag() const;
   void set_aarch64_singlestep_flag();
 
   void print_register_file(FILE* f) const;