Built motion from commit 6a09e18b.|2.6.11

[motion2.git] / legacy-libs / grpc-cloned / deps / grpc / third_party / upb / upb / pb / varint.int.h

diff --git a/legacy-libs/grpc-cloned/deps/grpc/third_party/upb/upb/pb/varint.int.h b/legacy-libs/grpc-cloned/deps/grpc/third_party/upb/upb/pb/varint.int.h
new file mode 100644 (file)
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--- /dev/null
+++ b/legacy-libs/grpc-cloned/deps/grpc/third_party/upb/upb/pb/varint.int.h
@@ -0,0 +1,164 @@
+/*
+** A number of routines for varint manipulation (we keep them all around to
+** have multiple approaches available for benchmarking).
+*/
+
+#ifndef UPB_VARINT_DECODER_H_
+#define UPB_VARINT_DECODER_H_
+
+#include <assert.h>
+#include <stdint.h>
+#include <string.h>
+#include "upb/upb.h"
+
+#include "upb/port_def.inc"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define UPB_MAX_WIRE_TYPE 5
+
+/* The maximum number of bytes that it takes to encode a 64-bit varint. */
+#define UPB_PB_VARINT_MAX_LEN 10
+
+/* Array of the "native" (ie. non-packed-repeated) wire type for the given a
+ * descriptor type (upb_descriptortype_t). */
+extern const uint8_t upb_pb_native_wire_types[];
+
+UPB_INLINE uint64_t byteswap64(uint64_t val)
+{
+  return ((((val) & 0xff00000000000000ull) >> 56)
+    | (((val) & 0x00ff000000000000ull) >> 40)
+    | (((val) & 0x0000ff0000000000ull) >> 24)
+    | (((val) & 0x000000ff00000000ull) >> 8)
+    | (((val) & 0x00000000ff000000ull) << 8)
+    | (((val) & 0x0000000000ff0000ull) << 24)
+    | (((val) & 0x000000000000ff00ull) << 40)
+    | (((val) & 0x00000000000000ffull) << 56));
+}
+
+/* Zig-zag encoding/decoding **************************************************/
+
+UPB_INLINE int32_t upb_zzdec_32(uint32_t n) {
+  return (n >> 1) ^ -(int32_t)(n & 1);
+}
+UPB_INLINE int64_t upb_zzdec_64(uint64_t n) {
+  return (n >> 1) ^ -(int64_t)(n & 1);
+}
+UPB_INLINE uint32_t upb_zzenc_32(int32_t n) {
+  return ((uint32_t)n << 1) ^ (n >> 31);
+}
+UPB_INLINE uint64_t upb_zzenc_64(int64_t n) {
+  return ((uint64_t)n << 1) ^ (n >> 63);
+}
+
+/* Decoding *******************************************************************/
+
+/* All decoding functions return this struct by value. */
+typedef struct {
+  const char *p;  /* NULL if the varint was unterminated. */
+  uint64_t val;
+} upb_decoderet;
+
+UPB_INLINE upb_decoderet upb_decoderet_make(const char *p, uint64_t val) {
+  upb_decoderet ret;
+  ret.p = p;
+  ret.val = val;
+  return ret;
+}
+
+upb_decoderet upb_vdecode_max8_branch32(upb_decoderet r);
+upb_decoderet upb_vdecode_max8_branch64(upb_decoderet r);
+
+/* Template for a function that checks the first two bytes with branching
+ * and dispatches 2-10 bytes with a separate function.  Note that this may read
+ * up to 10 bytes, so it must not be used unless there are at least ten bytes
+ * left in the buffer! */
+#define UPB_VARINT_DECODER_CHECK2(name, decode_max8_function)                  \
+UPB_INLINE upb_decoderet upb_vdecode_check2_ ## name(const char *_p) {         \
+  uint8_t *p = (uint8_t*)_p;                                                   \
+  upb_decoderet r;                                                             \
+  if ((*p & 0x80) == 0) {                                                      \
+  /* Common case: one-byte varint. */                                          \
+    return upb_decoderet_make(_p + 1, *p & 0x7fU);                             \
+  }                                                                            \
+  r = upb_decoderet_make(_p + 2, (*p & 0x7fU) | ((*(p + 1) & 0x7fU) << 7));    \
+  if ((*(p + 1) & 0x80) == 0) {                                                \
+    /* Two-byte varint. */                                                     \
+    return r;                                                                  \
+  }                                                                            \
+  /* Longer varint, fallback to out-of-line function. */                       \
+  return decode_max8_function(r);                                              \
+}
+
+UPB_VARINT_DECODER_CHECK2(branch32, upb_vdecode_max8_branch32)
+UPB_VARINT_DECODER_CHECK2(branch64, upb_vdecode_max8_branch64)
+#undef UPB_VARINT_DECODER_CHECK2
+
+/* Our canonical functions for decoding varints, based on the currently
+ * favored best-performing implementations. */
+UPB_INLINE upb_decoderet upb_vdecode_fast(const char *p) {
+  if (sizeof(long) == 8)
+    return upb_vdecode_check2_branch64(p);
+  else
+    return upb_vdecode_check2_branch32(p);
+}
+
+
+/* Encoding *******************************************************************/
+
+UPB_INLINE int upb_value_size(uint64_t val) {
+#ifdef __GNUC__
+  int high_bit = 63 - __builtin_clzll(val);  /* 0-based, undef if val == 0. */
+#else
+  int high_bit = 0;
+  uint64_t tmp = val;
+  while(tmp >>= 1) high_bit++;
+#endif
+  return val == 0 ? 1 : high_bit / 8 + 1;
+}
+
+/* Encodes a 64-bit varint into buf (which must be >=UPB_PB_VARINT_MAX_LEN
+ * bytes long), returning how many bytes were used.
+ *
+ * TODO: benchmark and optimize if necessary. */
+UPB_INLINE size_t upb_vencode64(uint64_t val, char *buf) {
+  size_t i;
+  if (val == 0) { buf[0] = 0; return 1; }
+  i = 0;
+  while (val) {
+    uint8_t byte = val & 0x7fU;
+    val >>= 7;
+    if (val) byte |= 0x80U;
+    buf[i++] = byte;
+  }
+  return i;
+}
+
+UPB_INLINE size_t upb_varint_size(uint64_t val) {
+  char buf[UPB_PB_VARINT_MAX_LEN];
+  return upb_vencode64(val, buf);
+}
+
+/* Encodes a 32-bit varint, *not* sign-extended. */
+UPB_INLINE uint64_t upb_vencode32(uint32_t val) {
+  char buf[UPB_PB_VARINT_MAX_LEN];
+  size_t bytes = upb_vencode64(val, buf);
+  uint64_t ret = 0;
+  UPB_ASSERT(bytes <= 5);
+  memcpy(&ret, buf, bytes);
+#ifdef UPB_BIG_ENDIAN
+  ret = byteswap64(ret);
+#endif
+  UPB_ASSERT(ret <= 0xffffffffffU);
+  return ret;
+}
+
+#ifdef __cplusplus
+}  /* extern "C" */
+#endif
+
+#include "upb/port_undef.inc"
+
+#endif  /* UPB_VARINT_DECODER_H_ */