fly316/PX4-Autopilot
7
0
Fork 0
mirror of https://gitee.com/mirrors_PX4/PX4-Autopilot.git synced 2026-07-13 08:50:35 +08:00
Code Issues Packages Projects Releases Wiki Activity

Separated bit array copy algorithms - aligned to unaligned and vice versa.

Browse Source
This commit is contained in:
Pavel Kirienko
2015-01-11 03:46:25 +03:00
parent c1fac577f3
commit 21c07b90a5
2 changed files with 20 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files
libuavcan/include/uavcan/marshal/bit_stream.hpp
+18 -4
View File
@@ -12,7 +12,14 @@
namespace uavcan
{
/**
* This function implements fast copy of unaligned bit arrays. It isn't part of the library API, so it is not exported.
* @param src_org Source array
* @param src_offset Bit offset of the first source byte
* @param src_len Number of bits to copy
* @param dst_org Destination array
* @param dst_offset Bit offset of the first destination byte
*/
void bitarrayCopy(const unsigned char* src_org, unsigned src_offset, unsigned src_len,
unsigned char* dst_org, unsigned dst_offset);
@@ -30,11 +37,18 @@ class UAVCAN_EXPORT BitStream
static inline unsigned bitlenToBytelen(unsigned bits) { return (bits + 7) / 8; }
static inline void copyBitArray(const uint8_t* src_org, unsigned src_offset, unsigned src_len,
uint8_t* dst_org, unsigned dst_offset)
static inline void copyBitArrayAlignedToUnaligned(const uint8_t* src_org, unsigned src_len,
uint8_t* dst_org, unsigned dst_offset)
{
bitarrayCopy(reinterpret_cast<const unsigned char*>(src_org), 0, src_len,
reinterpret_cast<unsigned char*>(dst_org), dst_offset);
}
static inline void copyBitArrayUnalignedToAligned(const uint8_t* src_org, unsigned src_offset, unsigned src_len,
uint8_t* dst_org)
{
bitarrayCopy(reinterpret_cast<const unsigned char*>(src_org), src_offset, src_len,
reinterpret_cast<unsigned char*>(dst_org), dst_offset);
reinterpret_cast<unsigned char*>(dst_org), 0);
}
public:
libuavcan/src/marshal/uc_bit_stream.cpp
+2 -2
View File
@@ -23,7 +23,7 @@ int BitStream::write(const uint8_t* bytes, const unsigned bitlen)
tmp[0] = tmp[bytelen - 1] = 0;
fill(tmp, tmp + bytelen, uint8_t(0));
copyBitArray(bytes, 0, bitlen, tmp, bit_offset_ % 8);
copyBitArrayAlignedToUnaligned(bytes, bitlen, tmp, bit_offset_ % 8);
const unsigned new_bit_offset = bit_offset_ + bitlen;
@@ -70,7 +70,7 @@ int BitStream::read(uint8_t* bytes, const unsigned bitlen)
}
fill(bytes, bytes + bitlenToBytelen(bitlen), uint8_t(0));
copyBitArray(tmp, bit_offset_ % 8, bitlen, bytes, 0);
copyBitArrayUnalignedToAligned(tmp, bit_offset_ % 8, bitlen, bytes);
bit_offset_ += bitlen;
return ResultOk;
}