reference: StreamGetSzPtr

git-svn-id: svn://ultimatepp.org/upp/trunk@8301 f0d560ea-af0d-0410-9eb7-867de7ffcac7

reference/Qtf/main.cpp

@@ -37,7 +37,7 @@ const char *examples[] = {
 	"{{1:1:1|2 A1::-2 A2:: A3:: B1:: B2:: B3}}",
 	"{{1:2 A1:: A2:: B1:: {{1:2 a1:: a2:: a1:: a2}}}}",
 	"{{1~a30/50o Round border}}",
-	NULL
+	NULL 
 };
 
 GUI_APP_MAIN

reference/StreamGetSzPtr/StreamGetSzPtr.cpp

@@ -0,0 +1,61 @@
+#include <Core/Core.h>
+
+using namespace Upp;
+
+int CountLines(Stream& s)
+{
+	int n = 0;
+	int c;
+	while((c = s.Get()) >= 0)
+		n += c == '\n';
+	return n;
+}
+
+int CountLinesOptimized(Stream& s)
+{
+	int n = 0;
+	for(;;) {
+		int sz;
+		const byte *p = s.GetSzPtr(sz);
+		if(sz) {
+			const byte *e = p + sz;
+			const byte *e4 = p + (sz & ~3);
+			while(p < e4) {
+				n += (p[0] == '\n' || p[1] == '\n' || p[2] == '\n' || p[3] == '\n');
+				p += 4;
+			}
+			while(p < e)
+				n += *p++ == '\n';
+		}
+		else {
+			int c = s.Get();
+			if(c < 0)
+				return n;
+			n += c == '\n';
+		}
+	}
+	return n;
+}
+
+CONSOLE_APP_MAIN
+{
+	StdLogSetup(LOG_FILE|LOG_COUT);
+	
+	const Vector<String>& arg = CommandLine();
+	if(arg.GetCount() == 0) {
+		RLOG("Please provide testing file path as argument, preferably >500MB");
+		return;
+	}
+	
+	{
+		RTIMESTOP("Simple");
+		FileIn in(arg[0]);
+		RDUMP(CountLines(in));
+	}
+
+	{
+		RTIMESTOP("Optimized");
+		FileIn in(arg[0]);
+		RDUMP(CountLinesOptimized(in));
+	}
+}

reference/StreamGetSzPtr/StreamGetSzPtr.upp

@@ -0,0 +1,11 @@
+description "Using Stream::GetSzPtr to optimize the algorithm to count lines in Stream\377";
+
+uses
+	Core;
+
+file
+	StreamGetSzPtr.cpp;
+
+mainconfig
+	"" = "SSE2";
+

reference/StreamGetSzPtr/init

@@ -0,0 +1,4 @@
+#ifndef _StreamGetSzPtr_icpp_init_stub
+#define _StreamGetSzPtr_icpp_init_stub
+#include "Core/init"
+#endif