wpi(4): add some branch predictions

[avos]

Test Plan

Tested with Intel 3945BG, STA mode

head/sys/dev/wpi/if_wpi.c

 #include <wctype.h>
 
 #include "fastmatch.h"
 #include "grep.h"
 
 static int       linesqueued;
 static int         procline(struct str *l, int);
 
+static int       lasta;
+static bool      ctxover;
+
 bool
 file_matching(const char *fname)
 {
         char *fname_base, *fname_buf;
         bool ret;
 
         ret = finclude ? false : true;
         fname_buf = strdup(fname);
if (!sflag)
                         warn("%s", fn);
                 return (0);
         }
 
         ln.file = grep_malloc(strlen(fn) + 1);
         strcpy(ln.file, fn);
         ln.line_no = 0;
         ln.len = 0;
+        ctxover = false;
         linesqueued = 0;
         tail = 0;
+        lasta = 0;
         ln.off = -1;
 
         for (c = 0;  c == 0 || !(lflag || qflag); ) {
                 ln.off += ln.len + 1;
                 if ((ln.dat = grep_fgetln(f, &ln.len)) == NULL || ln.len == 0) {
                         if (ln.line_no == 0 && matchall)
                                 exit(0);
                         else
                                 break;
                 }
                 if (ln.len > 0 && ln.dat[ln.len - 1] == fileeol)
                         --ln.len;
                 ln.line_no++;
 
                 /* Return if we need to skip a binary file */
                 if (f->binary && binbehave == BINFILE_SKIP) {
                         grep_close(f);
                         free(ln.file);
                         free(f);
                         return (0);
                 }
-                /* Process the file line-by-line */
+
+                /* Process the file line-by-line, enqueue non-matching lines */
                 if ((t = procline(&ln, f->binary)) == 0 && Bflag > 0) {
+                        /* Except don't enqueue lines that appear in -A ctx */
+                        if (ln.line_no == 0 || lasta != ln.line_no) {
+                                /* queue is maxed to Bflag number of lines */
                                 enqueue(&ln);
                                 linesqueued++;
+                                ctxover = false;
+                        } else {
+                                /*
+                                 * Indicate to procline() that we have ctx
+                                 * overlap and make sure queue is empty.
+                                 */
+                                if (!ctxover)
+                                        clearqueue();
+                                ctxover = true;
                         }
+                }
                 c += t;
                 if (mflag && mcount <= 0)
                         break;
         }
         if (Bflag > 0)
                 clearqueue();
         grep_close(f);
 
if (mflag)
                 mcount -= c;
 
         if (c && binbehave == BINFILE_BIN && nottext)
                 return (c); /* Binary file */
 
         /* Dealing with the context */
         if ((tail || c) && !cflag && !qflag && !lflag && !Lflag) {
                 if (c) {
-                        if (!first && !prev && !tail && Aflag)
+                        if (!first && !prev && !tail && (Bflag || Aflag) &&
+                            !ctxover)
                                 printf("--\n");
                         tail = Aflag;
                         if (Bflag > 0) {
-                                if (!first && !prev)
-                                        printf("--\n");
                                 printqueue();
+                                ctxover = false;
                         }
                         linesqueued = 0;
                         printline(l, ':', matches, m);
                 } else {
+                        /* Print -A lines following matches */
+                        lasta = l->line_no;
                         printline(l, '-', matches, m);
                         tail--;
                 }
         }
 
         if (c) {
                 prev = true;
                 first = false;