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-rw-r--r--src/liblzma/rangecoder/price_tablegen.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/src/liblzma/rangecoder/price_tablegen.c b/src/liblzma/rangecoder/price_tablegen.c
new file mode 100644
index 0000000..bf08ce3
--- /dev/null
+++ b/src/liblzma/rangecoder/price_tablegen.c
@@ -0,0 +1,87 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file price_tablegen.c
+/// \brief Probability price table generator
+///
+/// Compiling: gcc -std=c99 -o price_tablegen price_tablegen.c
+///
+// Authors: Igor Pavlov
+// Lasse Collin
+//
+// This file has been put into the public domain.
+// You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <inttypes.h>
+#include <stdio.h>
+#include "range_common.h"
+#include "price.h"
+
+
+static uint32_t rc_prices[RC_PRICE_TABLE_SIZE];
+
+
+static void
+init_price_table(void)
+{
+ for (uint32_t i = (UINT32_C(1) << RC_MOVE_REDUCING_BITS) / 2;
+ i < RC_BIT_MODEL_TOTAL;
+ i += (UINT32_C(1) << RC_MOVE_REDUCING_BITS)) {
+ const uint32_t cycles_bits = RC_BIT_PRICE_SHIFT_BITS;
+ uint32_t w = i;
+ uint32_t bit_count = 0;
+
+ for (uint32_t j = 0; j < cycles_bits; ++j) {
+ w *= w;
+ bit_count <<= 1;
+
+ while (w >= (UINT32_C(1) << 16)) {
+ w >>= 1;
+ ++bit_count;
+ }
+ }
+
+ rc_prices[i >> RC_MOVE_REDUCING_BITS]
+ = (RC_BIT_MODEL_TOTAL_BITS << cycles_bits)
+ - 15 - bit_count;
+ }
+
+ return;
+}
+
+
+static void
+print_price_table(void)
+{
+ printf("/* This file has been automatically generated by "
+ "price_tablegen.c. */\n\n"
+ "#include \"range_encoder.h\"\n\n"
+ "const uint8_t lzma_rc_prices["
+ "RC_PRICE_TABLE_SIZE] = {");
+
+ const size_t array_size = sizeof(lzma_rc_prices)
+ / sizeof(lzma_rc_prices[0]);
+ for (size_t i = 0; i < array_size; ++i) {
+ if (i % 8 == 0)
+ printf("\n\t");
+
+ printf("%4" PRIu32, rc_prices[i]);
+
+ if (i != array_size - 1)
+ printf(",");
+ }
+
+ printf("\n};\n");
+
+ return;
+}
+
+
+int
+main(void)
+{
+ init_price_table();
+ print_price_table();
+ return 0;
+}