Revert "hal: remove unused code"

This reverts commit 2d5ec61.

hal/armv7a/arch/cpu.h

@@ -195,6 +195,12 @@ static inline void *hal_cpuGetUserSP(cpu_context_t *ctx)
 }
 
 
+static inline int hal_cpuSupervisorMode(cpu_context_t *ctx)
+{
+	return ctx->psr & 0xf;
+}
+
+
 static inline unsigned int hal_cpuGetID(void)
 {
 	return 0;

hal/armv7m/arch/cpu.h

@@ -250,6 +250,12 @@ static inline void *hal_cpuGetUserSP(cpu_context_t *ctx)
 }
 
 
+static inline int hal_cpuSupervisorMode(cpu_context_t *ctx)
+{
+	return 0;
+}
+
+
 static inline int hal_cpuPushSignal(void *kstack, void (*handler)(void), int sig)
 {
 	return 0;

hal/cpu.h

@@ -88,6 +88,9 @@ extern void *hal_cpuGetSP(cpu_context_t *ctx);
 extern void *hal_cpuGetUserSP(cpu_context_t *ctx);
 
 
+extern int hal_cpuSupervisorMode(cpu_context_t *ctx);
+
+
 extern int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n);
 
 

hal/ia32/arch/cpu.h

@@ -320,6 +320,12 @@ static inline void *hal_cpuGetUserSP(cpu_context_t *ctx)
 }
 
 
+static inline int hal_cpuSupervisorMode(cpu_context_t *ctx)
+{
+	return ((ctx->cs & 3) == 0);
+}
+
+
 #endif
 
 #endif

hal/riscv64/arch/cpu.h

@@ -208,6 +208,12 @@ static inline void *hal_cpuGetUserSP(cpu_context_t *ctx)
 }
 
 
+static inline int hal_cpuSupervisorMode(cpu_context_t *ctx)
+{
+	return (ctx->sscratch == 0);
+}
+
+
 static inline int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n)
 {
 #if 0