(svn r26195) -Codechange: move debug's ottd_rdtsc (CPU specific high precision timer) into cpu.h/cpp

src/cpu.cpp

@@ -0,0 +1,76 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file cpu.cpp OS/CPU/compiler dependant real time tick sampling. */
+
+#include "stdafx.h"
+
+#undef RDTSC_AVAILABLE
+
+/* rdtsc for MSC_VER, uses simple inline assembly, or _rdtsc
+ * from external win64.asm because VS2005 does not support inline assembly */
+#if defined(_MSC_VER) && !defined(RDTSC_AVAILABLE) && !defined(WINCE)
+#include <intrin.h>
+uint64 ottd_rdtsc()
+{
+	return __rdtsc();
+}
+#define RDTSC_AVAILABLE
+#endif
+
+/* rdtsc for OS/2. Hopefully this works, who knows */
+#if defined (__WATCOMC__) && !defined(RDTSC_AVAILABLE)
+unsigned __int64 ottd_rdtsc();
+# pragma aux ottd_rdtsc = 0x0F 0x31 value [edx eax] parm nomemory modify exact [edx eax] nomemory;
+# define RDTSC_AVAILABLE
+#endif
+
+/* rdtsc for all other *nix-en (hopefully). Use GCC syntax */
+#if (defined(__i386__) || defined(__x86_64__)) && !defined(__DJGPP__) && !defined(RDTSC_AVAILABLE)
+uint64 ottd_rdtsc()
+{
+	uint32 high, low;
+	__asm__ __volatile__ ("rdtsc" : "=a" (low), "=d" (high));
+	return ((uint64)high << 32) | low;
+}
+# define RDTSC_AVAILABLE
+#endif
+
+/* rdtsc for PPC which has this not */
+#if (defined(__POWERPC__) || defined(__powerpc__)) && !defined(RDTSC_AVAILABLE)
+uint64 ottd_rdtsc()
+{
+	uint32 high = 0, high2 = 0, low;
+	/* PPC does not have rdtsc, so we cheat by reading the two 32-bit time-counters
+	 * it has, 'Move From Time Base (Upper)'. Since these are two reads, in the
+	 * very unlikely event that the lower part overflows to the upper part while we
+	 * read it; we double-check and reread the registers */
+	asm volatile (
+				  "mftbu %0\n"
+				  "mftb %1\n"
+				  "mftbu %2\n"
+				  "cmpw %3,%4\n"
+				  "bne- $-16\n"
+				  : "=r" (high), "=r" (low), "=r" (high2)
+				  : "0" (high), "2" (high2)
+				  );
+	return ((uint64)high << 32) | low;
+}
+# define RDTSC_AVAILABLE
+#endif
+
+/* In all other cases we have no support for rdtsc. No major issue,
+ * you just won't be able to profile your code with TIC()/TOC() */
+#if !defined(RDTSC_AVAILABLE)
+/* MSVC (in case of WinCE) can't handle #warning */
+# if !defined(_MSC_VER)
+#warning "(non-fatal) No support for rdtsc(), you won't be able to profile with TIC/TOC"
+# endif
+uint64 ottd_rdtsc() {return 0;}
+#endif