Imported Upstream version 1.4.13+git200906171200

gl/streq.h

@@ -0,0 +1,176 @@
+/* Optimized string comparison.
+   Copyright (C) 2001-2002, 2007 Free Software Foundation, Inc.
+
+   This program 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; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>.  */
+
+#ifndef _GL_STREQ_H
+#define _GL_STREQ_H
+
+#include <string.h>
+
+/* STREQ allows to optimize string comparison with a small literal string.
+     STREQ (s, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0)
+   is semantically equivalent to
+     strcmp (s, "EUC-KR") == 0
+   just faster.  */
+
+/* Help GCC to generate good code for string comparisons with
+   immediate strings. */
+#if defined (__GNUC__) && defined (__OPTIMIZE__)
+
+static inline int
+streq9 (const char *s1, const char *s2)
+{
+  return strcmp (s1 + 9, s2 + 9) == 0;
+}
+
+static inline int
+streq8 (const char *s1, const char *s2, char s28)
+{
+  if (s1[8] == s28)
+    {
+      if (s28 == 0)
+        return 1;
+      else
+        return streq9 (s1, s2);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq7 (const char *s1, const char *s2, char s27, char s28)
+{
+  if (s1[7] == s27)
+    {
+      if (s27 == 0)
+        return 1;
+      else
+        return streq8 (s1, s2, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq6 (const char *s1, const char *s2, char s26, char s27, char s28)
+{
+  if (s1[6] == s26)
+    {
+      if (s26 == 0)
+        return 1;
+      else
+        return streq7 (s1, s2, s27, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq5 (const char *s1, const char *s2, char s25, char s26, char s27, char s28)
+{
+  if (s1[5] == s25)
+    {
+      if (s25 == 0)
+        return 1;
+      else
+        return streq6 (s1, s2, s26, s27, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq4 (const char *s1, const char *s2, char s24, char s25, char s26, char s27, char s28)
+{
+  if (s1[4] == s24)
+    {
+      if (s24 == 0)
+        return 1;
+      else
+        return streq5 (s1, s2, s25, s26, s27, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq3 (const char *s1, const char *s2, char s23, char s24, char s25, char s26, char s27, char s28)
+{
+  if (s1[3] == s23)
+    {
+      if (s23 == 0)
+        return 1;
+      else
+        return streq4 (s1, s2, s24, s25, s26, s27, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq2 (const char *s1, const char *s2, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
+{
+  if (s1[2] == s22)
+    {
+      if (s22 == 0)
+        return 1;
+      else
+        return streq3 (s1, s2, s23, s24, s25, s26, s27, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq1 (const char *s1, const char *s2, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
+{
+  if (s1[1] == s21)
+    {
+      if (s21 == 0)
+        return 1;
+      else
+        return streq2 (s1, s2, s22, s23, s24, s25, s26, s27, s28);
+    }
+  else
+    return 0;
+}
+
+static inline int
+streq0 (const char *s1, const char *s2, char s20, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
+{
+  if (s1[0] == s20)
+    {
+      if (s20 == 0)
+        return 1;
+      else
+        return streq1 (s1, s2, s21, s22, s23, s24, s25, s26, s27, s28);
+    }
+  else
+    return 0;
+}
+
+#define STREQ(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
+  streq0 (s1, s2, s20, s21, s22, s23, s24, s25, s26, s27, s28)
+
+#else
+
+#define STREQ(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
+  (strcmp (s1, s2) == 0)
+
+#endif
+
+#endif /* _GL_STREQ_H */