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Diffstat (limited to 'WebKitTools/android/flex-2.5.4a/MISC/fastwc')
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/README | 56 | ||||
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/mywc.c | 26 | ||||
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc1.l | 18 | ||||
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc2.l | 20 | ||||
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc3.l | 24 | ||||
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc4.l | 27 | ||||
| -rw-r--r-- | WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc5.l | 24 |
7 files changed, 0 insertions, 195 deletions
diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/README b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/README deleted file mode 100644 index 0dd3afe..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/README +++ /dev/null @@ -1,56 +0,0 @@ -This directory contains some examples illustrating techniques for extracting -high-performance from flex scanners. Each program implements a simplified -version of the Unix "wc" tool: read text from stdin and print the number of -characters, words, and lines present in the text. All programs were compiled -using gcc (version unavailable, sorry) with the -O flag, and run on a -SPARCstation 1+. The input used was a PostScript file, mainly containing -figures, with the following "wc" counts: - - lines words characters - 214217 635954 2592172 - - -The basic principles illustrated by these programs are: - - - match as much text with each rule as possible - - adding rules does not slow you down! - - avoid backing up - -and the big caveat that comes with them is: - - - you buy performance with decreased maintainability; make - sure you really need it before applying the above techniques. - -See the "Performance Considerations" section of flexdoc for more -details regarding these principles. - - -The different versions of "wc": - - mywc.c - a simple but fairly efficient C version - - wc1.l a naive flex "wc" implementation - - wc2.l somewhat faster; adds rules to match multiple tokens at once - - wc3.l faster still; adds more rules to match longer runs of tokens - - wc4.l fastest; still more rules added; hard to do much better - using flex (or, I suspect, hand-coding) - - wc5.l identical to wc3.l except one rule has been slightly - shortened, introducing backing-up - -Timing results (all times in user CPU seconds): - - program time notes - ------- ---- ----- - wc1 16.4 default flex table compression (= -Cem) - wc1 6.7 -Cf compression option - /bin/wc 5.8 Sun's standard "wc" tool - mywc 4.6 simple but better C implementation! - wc2 4.6 as good as C implementation; built using -Cf - wc3 3.8 -Cf - wc4 3.3 -Cf - wc5 5.7 -Cf; ouch, backing up is expensive diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/mywc.c b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/mywc.c deleted file mode 100644 index 92e5a36..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/mywc.c +++ /dev/null @@ -1,26 +0,0 @@ -/* A simple but fairly efficient C version of the Unix "wc" tool */ - -#include <stdio.h> -#include <ctype.h> - -main() -{ - register int c, cc = 0, wc = 0, lc = 0; - FILE *f = stdin; - - while ((c = getc(f)) != EOF) { - ++cc; - if (isgraph(c)) { - ++wc; - do { - c = getc(f); - if (c == EOF) - goto done; - ++cc; - } while (isgraph(c)); - } - if (c == '\n') - ++lc; - } -done: printf( "%8d%8d%8d\n", lc, wc, cc ); -} diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc1.l b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc1.l deleted file mode 100644 index d6696bc..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc1.l +++ /dev/null @@ -1,18 +0,0 @@ -/* First cut at a flex-based "wc" tool. */ - -ws [ \t] -nonws [^ \t\n] - -%% - int cc = 0, wc = 0, lc = 0; - -{nonws}+ cc += yyleng; ++wc; - -{ws}+ cc += yyleng; - -\n ++lc; ++cc; - -<<EOF>> { - printf( "%8d %8d %8d\n", lc, wc, cc ); - yyterminate(); - } diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc2.l b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc2.l deleted file mode 100644 index bd63cd4..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc2.l +++ /dev/null @@ -1,20 +0,0 @@ -/* Somewhat faster "wc" tool: match more text with each rule */ - -ws [ \t] -nonws [^ \t\n] -word {ws}*{nonws}+ - -%% - int cc = 0, wc = 0, lc = 0; - -{word}{ws}* cc += yyleng; ++wc; -{word}{ws}*\n cc += yyleng; ++wc; ++lc; - -{ws}+ cc += yyleng; - -\n+ cc += yyleng; lc += yyleng; - -<<EOF>> { - printf( "%8d %8d %8d\n", lc, wc, cc ); - yyterminate(); - } diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc3.l b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc3.l deleted file mode 100644 index 7c5f2e2..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc3.l +++ /dev/null @@ -1,24 +0,0 @@ -/* Somewhat faster still: potentially match a lot of text with each rule */ - -ws [ \t] -nonws [^ \t\n] -word {ws}*{nonws}+ -words {word}{ws}+ - -%% - int cc = 0, wc = 0, lc = 0; - -{word}{ws}* cc += yyleng; ++wc; -{word}{ws}*\n cc += yyleng; ++wc; ++lc; -{words}{word}{ws}* cc += yyleng; wc += 2; -{words}{2}{word}{ws}* cc += yyleng; wc += 3; -{words}{3}{word}{ws}* cc += yyleng; wc += 4; - -{ws}+ cc += yyleng; - -\n+ cc += yyleng; lc += yyleng; - -<<EOF>> { - printf( "%8d %8d %8d\n", lc, wc, cc ); - yyterminate(); - } diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc4.l b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc4.l deleted file mode 100644 index cbe56f6..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc4.l +++ /dev/null @@ -1,27 +0,0 @@ -/* Fastest version of wc: add rules to pick up newlines, too */ - -ws [ \t] -nonws [^ \t\n] -word {ws}*{nonws}+ -words {word}{ws}+ - -%% - int cc = 0, wc = 0, lc = 0; - -{word}{ws}* ++wc; cc += yyleng; -{word}{ws}*\n ++wc; cc += yyleng; ++lc; -{words}{word}{ws}* wc += 2; cc += yyleng; -{words}{word}{ws}*\n wc += 2; cc += yyleng; ++lc; -{words}{2}{word}{ws}* wc += 3; cc += yyleng; -{words}{2}{word}{ws}*\n wc += 3; cc += yyleng; ++lc; -{words}{3}{word}{ws}* wc += 4; cc += yyleng; -{words}{3}{word}{ws}*\n wc += 4; cc += yyleng; ++lc; - -{ws}+ cc += yyleng; - -\n+ cc += yyleng; lc += yyleng; - -<<EOF>> { - printf( "%8d %8d %8d\n", lc, wc, cc ); - yyterminate(); - } diff --git a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc5.l b/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc5.l deleted file mode 100644 index 8fe17b6..0000000 --- a/WebKitTools/android/flex-2.5.4a/MISC/fastwc/wc5.l +++ /dev/null @@ -1,24 +0,0 @@ -/* Oops; slight change from wc3.l introduces backtracking */ - -ws [ \t] -nonws [^ \t\n] -word {ws}*{nonws}+ -words {word}{ws}+ - -%% - int cc = 0, wc = 0, lc = 0; - -{word}{ws}* cc += yyleng; ++wc; -{word}{ws}*\n cc += yyleng; ++wc; ++lc; -{words}{word} cc += yyleng; wc += 2; /* oops */ -{words}{2}{word}{ws}* cc += yyleng; wc += 3; -{words}{3}{word}{ws}* cc += yyleng; wc += 4; - -{ws}+ cc += yyleng; - -\n+ cc += yyleng; lc += yyleng; - -<<EOF>> { - printf( "%8d %8d %8d\n", lc, wc, cc ); - yyterminate(); - } |