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-rw-r--r--src/liblzma/lzma/lzma_common.h22
1 files changed, 12 insertions, 10 deletions
diff --git a/src/liblzma/lzma/lzma_common.h b/src/liblzma/lzma/lzma_common.h
index d46b8502..c3c587f0 100644
--- a/src/liblzma/lzma/lzma_common.h
+++ b/src/liblzma/lzma/lzma_common.h
@@ -125,31 +125,33 @@ typedef enum {
///
/// Match byte is used when the previous LZMA symbol was something else than
/// a literal (that is, it was some kind of match).
-#define LITERAL_CODER_SIZE 0x300
+#define LITERAL_CODER_SIZE UINT32_C(0x300)
/// Maximum number of literal coders
#define LITERAL_CODERS_MAX (1 << LZMA_LCLP_MAX)
+/// Calculates the literal_mask that literal_subcoder() needs.
+#define literal_mask_calc(lc, lp) \
+ ((UINT32_C(0x100) << (lp)) - (UINT32_C(0x100) >> (lc)))
+
/// Locate the literal coder for the next literal byte. The choice depends on
/// - the lowest literal_pos_bits bits of the position of the current
/// byte; and
/// - the highest literal_context_bits bits of the previous byte.
-#define literal_subcoder(probs, lc, lp_mask, pos, prev_byte) \
- ((probs)[(((pos) & (lp_mask)) << (lc)) \
- + ((uint32_t)(prev_byte) >> (8U - (lc)))])
+#define literal_subcoder(probs, lc, literal_mask, pos, prev_byte) \
+ ((probs) + UINT32_C(3) * \
+ (((((pos) << 8) + (prev_byte)) & (literal_mask)) << (lc)))
static inline void
-literal_init(probability (*probs)[LITERAL_CODER_SIZE],
- uint32_t lc, uint32_t lp)
+literal_init(probability *probs, uint32_t lc, uint32_t lp)
{
assert(lc + lp <= LZMA_LCLP_MAX);
- const uint32_t coders = 1U << (lc + lp);
+ const size_t coders = LITERAL_CODER_SIZE << (lc + lp);
- for (uint32_t i = 0; i < coders; ++i)
- for (uint32_t j = 0; j < LITERAL_CODER_SIZE; ++j)
- bit_reset(probs[i][j]);
+ for (size_t i = 0; i < coders; ++i)
+ bit_reset(probs[i]);
return;
}