Separate crc32 and crc32_combine tables so the crc32_combine tables are not included when not used if statically linking. Reduces code size by 4k.

1 files changed, 39 insertions, 18 deletions

diff --git a/tools/makecrct.c b/tools/makecrct.c
index 77116f7..323d0c0 100644
--- a/tools/makecrct.c
+++ b/tools/makecrct.c
@@ -14,7 +14,9 @@ static uint32_t crc_comb[GF2_DIM][GF2_DIM];
 
 static void gf2_matrix_square(uint32_t *square, const uint32_t *mat);
 static void make_crc_table(void);
-static void print_crc32_tables();
+static void make_crc_combine_table(void);
+static void print_crc_table(void);
+static void print_crc_combine_table(void);
 static void write_table(const uint32_t *, int);
 
 
@@ -52,7 +54,7 @@ static void gf2_matrix_square(uint32_t *square, const uint32_t *mat) {
   allow for word-at-a-time CRC calculation for both big-endian and little-
   endian machines, where a word is four bytes.
 */
-static void make_crc_table() {
+static void make_crc_table(void) {
     int n, k;
     uint32_t c;
     uint32_t poly;                       /* polynomial exclusive-or pattern */
@@ -83,7 +85,10 @@ static void make_crc_table() {
             crc_table[k + 4][n] = ZSWAP32(c);
         }
     }
+}
 
+static void make_crc_combine_table(void) {
+    int n, k;
     /* generate zero operators table for crc32_combine() */
 
     /* generate the operator to apply a single zero bit to a CRC -- the
@@ -110,7 +115,16 @@ static void make_crc_table() {
         gf2_matrix_square(crc_comb[n], crc_comb[n - 1]);
 }
 
-static void print_crc32_tables() {
+static void write_table(const uint32_t *table, int k) {
+    int n;
+
+    for (n = 0; n < k; n++)
+        printf("%s0x%08" PRIx32 "%s", n % 5 ? "" : "    ",
+                (uint32_t)(table[n]),
+                n == k - 1 ? "\n" : (n % 5 == 4 ? ",\n" : ", "));
+}
+
+static void print_crc_table(void) {
     int k;
     printf("#ifndef CRC32_TBL_H_\n");
     printf("#define CRC32_TBL_H_\n\n");
@@ -125,32 +139,39 @@ static void print_crc32_tables() {
         printf("  },\n  {\n");
         write_table(crc_table[k], 256);
     }
-    printf("  }\n};\n");
+    printf("  }\n};\n\n");
+
+    printf("#endif /* CRC32_TBL_H_ */\n");
+}
+
+static void print_crc_combine_table(void) {
+    int k;
+    printf("#ifndef CRC32_COMB_TBL_H_\n");
+    printf("#define CRC32_COMB_TBL_H_\n\n");
+    printf("/* crc32_comb_tbl.h -- zero operators table for CRC combine\n");
+    printf(" * Generated automatically by makecrct.c\n */\n\n");
 
     /* print zero operator table */
-    printf("\nstatic const uint32_t ");
+    printf("static const uint32_t ");
     printf("crc_comb[%d][%d] =\n{\n  {\n", GF2_DIM, GF2_DIM);
     write_table(crc_comb[0], GF2_DIM);
     for (k = 1; k < GF2_DIM; k++) {
         printf("  },\n  {\n");
         write_table(crc_comb[k], GF2_DIM);
     }
-    printf("  }\n};\n");
-    printf("#endif /* CRC32_TBL_H_ */\n");
-}
-
-static void write_table(const uint32_t *table, int k) {
-    int n;
+    printf("  }\n};\n\n");
 
-    for (n = 0; n < k; n++)
-        printf("%s0x%08" PRIx32 "%s", n % 5 ? "" : "    ",
-                (uint32_t)(table[n]),
-                n == k - 1 ? "\n" : (n % 5 == 4 ? ",\n" : ", "));
+    printf("#endif /* CRC32_COMB_TBL_H_ */\n");
 }
 
 // The output of this application can be piped out to recreate crc32.h
-int main() {
-    make_crc_table();
-    print_crc32_tables();
+int main(int argc, char *argv[]) {
+    if (argc > 1 && strcmp(argv[1], "-c") == 0) {
+        make_crc_combine_table();
+        print_crc_combine_table();
+    } else {
+        make_crc_table();
+        print_crc_table();
+    }
     return 0;
 }