From 75b42a7eb78aa18427de64593576482faffe992b Mon Sep 17 00:00:00 2001
From: powturbo <powturbo@gmail.com>
Date: Thu, 18 Jun 2015 17:39:01 +0200
Subject: [PATCH] BitUnpack: Direct Access/Update, FOR, Delta+FOR, SIMD

---
 bitunpack.h | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/bitunpack.h b/bitunpack.h
index 3117c68..be53d19 100644
--- a/bitunpack.h
+++ b/bitunpack.h
@@ -26,15 +26,17 @@
 #ifdef __cplusplus
 extern "C" {
 #endif
+#include <stdint.h>
 
 #include "conf.h"
 
-// ---------------- Unpack a previously bit packed (scalar bitpack32 or bipack16) integer array -----------------------------------------------------------------
+// ---------------- Unpack a bit packed integer array --------------------------------------------------------------------------------------
 // unpack a bitpacked integer array. Return value = end of packed buffer in 
-unsigned char *bitunpack16(unsigned char *__restrict in, unsigned n, unsigned short *__restrict out, unsigned b);
 unsigned char *bitunpack32(unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned b);
+unsigned char *bitunpack16(unsigned char *__restrict in, unsigned n, unsigned short *__restrict out, unsigned b);
+unsigned char *bitunpack64(unsigned char *__restrict in, unsigned n, uint64_t       *__restrict out, unsigned b);
 
-// ---------------- Direct Access to a single bit packed (see bitpack.h) integer array entry --------------------------------------------------------------------
+// ---------------- Direct Access to a single packed integer array entry --------------------------------------------------------------------
   #ifdef __AVX2__
 #include <x86intrin.h>
   #else
@@ -42,11 +44,11 @@ unsigned char *bitunpack32(unsigned char *__restrict in, unsigned n, unsigned
 #define _bzhi_u32(__u, __b) ((__u) & ((1u  <<__b)-1))
   #endif
 
-// Get a single 32 bits value with index "idx" (or bit index b*idx) from a previously bit packed (scalar bitpack32) integer array
+// Get a single 32 bits value with index "idx" (or bit index b*idx) from packed integer array
 static ALWAYS_INLINE unsigned  bitgetx32(unsigned char *__restrict in, unsigned b, unsigned  idx) { unsigned bidx = b*idx; return _bzhi_u64( (*(unsigned long long *)((unsigned *)in+(bidx>>5))) >> (bidx&0x1f), b ); }
 static ALWAYS_INLINE unsigned _bitgetx32(unsigned char *__restrict in, unsigned b, unsigned bidx) {                        return _bzhi_u64( (*(unsigned long long *)((unsigned *)in+(bidx>>5))) >> (bidx&0x1f), b ); }
 	
-// like  bitgetx32 but for 16 bits integer array (see scalar bitpack16)
+// like  bitgetx32 but for 16 bits integer array
 static ALWAYS_INLINE unsigned  bitgetx16(unsigned char *__restrict in, unsigned b, unsigned  idx) { unsigned bidx = b*idx; return _bzhi_u32( (*(unsigned           *)((unsigned *)in+(bidx>>4))) >> (bidx& 0xf), b ); }
 static ALWAYS_INLINE unsigned _bitgetx16(unsigned char *__restrict in, unsigned b, unsigned bidx) {                        return _bzhi_u32( (*(unsigned           *)((unsigned *)in+(bidx>>4))) >> (bidx& 0xf), b ); }
 
@@ -54,7 +56,7 @@ static ALWAYS_INLINE unsigned _bitgetx16(unsigned char *__restrict in, unsigned
 static ALWAYS_INLINE void      bitsetx32(unsigned char *__restrict in, unsigned b, unsigned  idx, unsigned v) { unsigned bidx = b*idx;  unsigned long long *p = (unsigned long long *)((unsigned *)in+(bidx>>5)); *p = ( *p & ~(((1ull<<b)-1) << (bidx&0x1f)) ) | (unsigned long long)v<<(bidx&0x1f);}
 static ALWAYS_INLINE void      bitsetx16(unsigned char *__restrict in, unsigned b, unsigned  idx, unsigned v) { unsigned bidx = b*idx;  unsigned           *p = (unsigned           *)             in+(bidx>>4) ; *p = ( *p & ~(((1u  <<b)-1) << (bidx& 0xf)) ) |                     v<<(bidx& 0xf);}
 
-// ---------------- Delta+FOR : integrated bitpacking, for delta packed SORTED array (Ex. DocId in inverted index) -------------------------------
+// ---------------- DFOR : integrated bitpacking, for delta packed SORTED array (Ex. DocId in inverted index) -------------------------------
 // start < out[0] < out[1] < ... < out[n-2] < out[n-1] < (1<<N)-1,    N=32,16
 // out[0] = start + in[0] + 1;  out[1] = out[0] + in[1] + 1; ... ;  out[i] = out[i-1] + in[i] +  1
 unsigned char *bitd1unpack32(  unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned start, unsigned b);
@@ -65,7 +67,7 @@ unsigned char *bitd1unpack16(  unsigned char *__restrict in, unsigned n, unsigne
 unsigned char *bitdunpack32( unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned start, unsigned b);
 unsigned char *bitdunpack16( unsigned char *__restrict in, unsigned n, unsigned short *__restrict out, unsigned start, unsigned b);
 
-// ---------------- FOR : Direct Access for packed SORTED array ---------------------------------------------------------------------
+// ---------------- For : Direct Access for packed SORTED array (Ex. DocId in inverted index) --------------------------------------------
 // out[i] = start + in[i] + i + 1
 unsigned char *bitf1unpack32( unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned start, unsigned b);
 unsigned char *bitf1unpack16( unsigned char *__restrict in, unsigned n, unsigned short *__restrict out, unsigned start, unsigned b);
@@ -74,8 +76,8 @@ unsigned char *bitf1unpack16( unsigned char *__restrict in, unsigned n, unsigned
 unsigned char *bitfunpack32(  unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned start, unsigned b);
 unsigned char *bitfunpack16(  unsigned char *__restrict in, unsigned n, unsigned short *__restrict out, unsigned start, unsigned b);
 
-// ---------------- SIMD : unpack a bit packed integer array (SIMD vertical bitpacking) --------------------------------------------------
-// SIMD unpack a bitpacked (see bitpackv32/bitdpackv32/bitd1packv32) integer array. Return value = end of packed buffer in
+// ---------------- SIMD : unpack a bit packed integer array -------------------------------------------------------------------------------
+// SIMD unpack a bitpacked integer array. Return value = end of packed buffer in
 unsigned char *bitunpackv32(  unsigned char *__restrict in, unsigned n, unsigned       *__restrict out				  , unsigned b);
 unsigned char *bitdunpackv32( unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned start, unsigned b);
 unsigned char *bitd1unpackv32(unsigned char *__restrict in, unsigned n, unsigned       *__restrict out, unsigned start, unsigned b);