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diff --git a/gs/src/gsbittab.h b/gs/src/gsbittab.h
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+/* Copyright (C) 1995, 1996 Aladdin Enterprises.  All rights reserved.
+  
+  This file is part of Aladdin Ghostscript.
+  
+  Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
+  or distributor accepts any responsibility for the consequences of using it,
+  or for whether it serves any particular purpose or works at all, unless he
+  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
+  License (the "License") for full details.
+  
+  Every copy of Aladdin Ghostscript must include a copy of the License,
+  normally in a plain ASCII text file named PUBLIC.  The License grants you
+  the right to copy, modify and redistribute Aladdin Ghostscript, but only
+  under certain conditions described in the License.  Among other things, the
+  License requires that the copyright notice and this notice be preserved on
+  all copies.
+*/
+
+/* gsbittab.h */
+/* Interface to tables for bit operations */
+
+/*
+ * Generate tables for transforming 2, 4, 6, or 8 bits.
+ */
+#define btab2_(v0,v2,v1)\
+  v0,v1+v0,v2+v0,v2+v1+v0
+#define bit_table_2(v0,v2,v1) btab2_(v0,v2,v1)
+#define btab4_(v0,v8,v4,v2,v1)\
+  btab2_(v0,v2,v1), btab2_(v4+v0,v2,v1),\
+  btab2_(v8+v0,v2,v1), btab2_(v8+v4+v0,v2,v1)
+#define bit_table_4(v0,v8,v4,v2,v1) btab4_(v0,v8,v4,v2,v1)
+#define btab6_(v0,v20,v10,v8,v4,v2,v1)\
+  btab4_(v0,v8,v4,v2,v1), btab4_(v10+v0,v8,v4,v2,v1),\
+  btab4_(v20+v0,v8,v4,v2,v1), btab4_(v20+v10+v0,v8,v4,v2,v1)
+#define bit_table_6(v0,v20,v10,v8,v4,v2,v1) btab6_(v0,v20,v10,v8,v4,v2,v1)
+#define bit_table_8(v0,v80,v40,v20,v10,v8,v4,v2,v1)\
+  btab6_(v0,v20,v10,v8,v4,v2,v1), btab6_(v40+v0,v20,v10,v8,v4,v2,v1),\
+  btab6_(v80+v0,v20,v10,v8,v4,v2,v1), btab6_(v80+v40+v0,v20,v10,v8,v4,v2,v1)
+
+/*
+ * byte_reverse_bits[B] = the byte B with the order of bits reversed.
+ */
+extern const byte byte_reverse_bits[256];
+
+/*
+ * byte_right_mask[N] = a byte with N trailing 1s, 0 <= N <= 8.
+ */
+extern const byte byte_right_mask[9];
+
+/*
+ * byte_count_bits[B] = the number of 1-bits in a byte with value B.
+ */
+extern const byte byte_count_bits[256];
+
+/*
+ * byte_bit_run_length_N[B], for 0 <= N <= 7, gives the length of the
+ * run of 1-bits starting at bit N in a byte with value B,
+ * numbering the bits in the byte as 01234567.  If the run includes
+ * the low-order bit (i.e., might be continued into a following byte),
+ * the run length is increased by 8.
+ */
+extern const byte
+  byte_bit_run_length_0[256], byte_bit_run_length_1[256],
+  byte_bit_run_length_2[256], byte_bit_run_length_3[256],
+  byte_bit_run_length_4[256], byte_bit_run_length_5[256],
+  byte_bit_run_length_6[256], byte_bit_run_length_7[256];
+
+/*
+ * byte_bit_run_length[N] points to byte_bit_run_length_N.
+ * byte_bit_run_length_neg[N] = byte_bit_run_length[-N & 7].
+ */
+extern const byte *byte_bit_run_length[8];
+extern const byte *byte_bit_run_length_neg[8];