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-rw-r--r--upb/pb/varint.c51
1 files changed, 0 insertions, 51 deletions
diff --git a/upb/pb/varint.c b/upb/pb/varint.c
index 25cdd81..90f58a1 100644
--- a/upb/pb/varint.c
+++ b/upb/pb/varint.c
@@ -72,54 +72,3 @@ done:
r.p = p;
return r;
}
-
-/* Given an encoded varint v, returns an integer with a single bit set that
- * indicates the end of the varint. Subtracting one from this value will
- * yield a mask that leaves only bits that are part of the varint. Returns
- * 0 if the varint is unterminated. */
-static uint64_t upb_get_vstopbit(uint64_t v) {
- uint64_t cbits = v | 0x7f7f7f7f7f7f7f7fULL;
- return ~cbits & (cbits+1);
-}
-
-/* A branchless decoder. Credit to Pascal Massimino for the bit-twiddling. */
-upb_decoderet upb_vdecode_max8_massimino(upb_decoderet r) {
- uint64_t b;
- uint64_t stop_bit;
- upb_decoderet my_r;
- memcpy(&b, r.p, sizeof(b));
- stop_bit = upb_get_vstopbit(b);
- b = (b & 0x7f7f7f7f7f7f7f7fULL) & (stop_bit - 1);
- b += b & 0x007f007f007f007fULL;
- b += 3 * (b & 0x0000ffff0000ffffULL);
- b += 15 * (b & 0x00000000ffffffffULL);
- if (stop_bit == 0) {
- /* Error: unterminated varint. */
- upb_decoderet err_r = {(void*)0, 0};
- return err_r;
- }
- my_r = upb_decoderet_make(r.p + ((__builtin_ctzll(stop_bit) + 1) / 8),
- r.val | (b << 7));
- return my_r;
-}
-
-/* A branchless decoder. Credit to Daniel Wright for the bit-twiddling. */
-upb_decoderet upb_vdecode_max8_wright(upb_decoderet r) {
- uint64_t b;
- uint64_t stop_bit;
- upb_decoderet my_r;
- memcpy(&b, r.p, sizeof(b));
- stop_bit = upb_get_vstopbit(b);
- b &= (stop_bit - 1);
- b = ((b & 0x7f007f007f007f00ULL) >> 1) | (b & 0x007f007f007f007fULL);
- b = ((b & 0xffff0000ffff0000ULL) >> 2) | (b & 0x0000ffff0000ffffULL);
- b = ((b & 0xffffffff00000000ULL) >> 4) | (b & 0x00000000ffffffffULL);
- if (stop_bit == 0) {
- /* Error: unterminated varint. */
- upb_decoderet err_r = {(void*)0, 0};
- return err_r;
- }
- my_r = upb_decoderet_make(r.p + ((__builtin_ctzll(stop_bit) + 1) / 8),
- r.val | (b << 14));
- return my_r;
-}
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