add rdtsc for x86

am/arch/x86-linux/include/arch.h

@@ -1,6 +1,8 @@
 #ifndef __TYPES_H__
 #define __TYPES_H__
 
+#include <unistd.h>
+
 typedef char i8;
 typedef unsigned char u8;
 typedef short int i16;

am/arch/x86-linux/src/ioe.c

@@ -12,8 +12,16 @@ ulong _uptime() {
   return seconds * 1000 + (useconds + 500) / 1000;
 }
 
+static inline long long rdtsc() {
+  int lo, hi;
+  asm volatile ("rdtscp": "=a"(lo), "=d"(hi) : : "%ecx");
+  return ((long long)hi << 32) | lo;
+}
+
+static long long init_tsc;
+
 ulong _cycles() {
-  return 0;
+  return rdtsc() - init_tsc;
 }
 
 void gui_init();
@@ -21,5 +29,6 @@ void gui_init();
 void _ioe_init() {
   gui_init();
   gettimeofday(&boot_time, NULL);
+  init_tsc = rdtsc();
 }
 

am/arch/x86-qemu/src/ioe.cpp

@@ -110,14 +110,27 @@ int _peek_key() {
   }
 }
 
+static inline long long rdtsc() {
+  int lo, hi;
+  asm volatile ("rdtscp": "=a"(lo), "=d"(hi) : : "%ecx");
+  return ((long long)hi << 32) | lo;
+}
+
+static long long init_tsc;
+
 void _ioe_init() {
   vga_init();
+  init_tsc = rdtsc();
 }
 
 ulong i386_uptime = 0;
 
+ulong _cycles() {
+  return rdtsc() - init_tsc;
+}
+
 ulong _uptime() {
-  return i386_uptime ++;
+  return i386_uptime;
 }
 
 _Screen _screen;

apps/tsc/README.md

@@ -0,0 +1,5 @@
+# Hello World
+
+最简单的Hello World程序，使用`_putc`打印一些字符，然后`_halt(0)`终止。
+
+能够运行在任何实现了AM的平台上。

apps/tsc/include/hello.h

@@ -0,0 +1,2 @@
+void print(const char *);
+void printi(int);

apps/tsc/src/hello.c

@@ -0,0 +1,18 @@
+#include <hello.h>
+#include <am.h>
+
+int main() {
+  _trm_init();
+  _ioe_init();
+
+  ulong t = _uptime();
+
+  for (int i = 0; i <= 10000; i ++) {
+    printi(_cycles());
+    print("\n");
+  }
+
+  printi(_uptime() - t);
+  print("ms\n");
+  _halt(0);
+}

apps/tsc/src/print.c

@@ -0,0 +1,22 @@
+#include <hello.h>
+#include <am.h>
+
+void print(const char *s) {
+  for (; *s; s ++) {
+    _putc(*s);
+  }
+}
+
+static void print_i(int i) {
+  if (i > 0) {
+    print_i(i / 10);
+    _putc('0' + (i % 10));
+  }
+}
+
+void printi(int i) {
+  if (i == 0) _putc('0');
+  else print_i(i);
+}
+
+