amosr

amos@localhost option-test $ swiftc uint.swift && ./main
2^62 = 4611686018427387904
2^63 - 1 = 9223372036854775807
Illegal instruction

# Running with -Ounchecked gives wrong result.. (last two numbers are same)
amos@localhost option-test $ swiftc tx1-uint.swift -Ounchecked  && ./main
2^62 = 4611686018427387904
2^63 - 1 = 9223372036854775807
2^63 = 9223372036854775807

amosr

 13> let y : UnsafeMutablePointer<UInt8> = unsafeDowncast(malloc(50))
repl.swift:13:39: error: generic parameter 'T' could not be inferred
let y : UnsafeMutablePointer<UInt8> = unsafeDowncast(malloc(50))
                                      ^
Swift.unsafeDowncast:12:13: note: in call to function 'unsafeDowncast'
public func unsafeDowncast<T : AnyObject>(x: AnyObject) -> T
            ^

 13> let y : UnsafeMutablePointer<UInt8> = unsafeDowncast<UnsafeMutablePointer<UInt8>>(malloc(50))
repl.swift:13:39: error: cannot explicitly specialize a generic function

amosr

#include <x86intrin.h>
#include <stdint.h>
#include <stdio.h>


static const uint32_t powers_of_ten_multipliers[]
 = { 10000000, 1000000, 100000, 10000
   , 1000    , 100    , 10    , 1
   , 0       , 0      , 0     , 0
   , 0       , 0      , 0     , 0

amosr

#include <fcntl.h>
#include <math.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/stat.h>

amosr

## $FILES is names of all files to be split
## splits files into two


# find largest file
largest=`ls $FILES -l | sort -k5 -nr | head -n1 | awk '{ print $9 }'`

# count how many lines in it
lines=`wc -l $largest`

amosr

Comparing the Icicle against Postgres

Using the ASX data. SQL to create table and index is:

create table asx (company char(3), date date, open double precision, high double precision, low double precision, close double precision, volume double precision, adjclose double precision);

amosr

#include <stdio.h>
#include <string.h>
#include <time.h>

typedef long long int uint64_t;

int cmp8_mask (const char *as, const char* bs, uint64_t len)
{
    uint64_t rem = len;
    while (rem > 8) {

amosr

/*
attempt at writing a faster memcmp
*/
static iint_t INLINE memcmp8 (const char *as, const char* bs, iint_t len)
{
    uint64_t *a = (uint64_t*)as;
    uint64_t *b = (uint64_t*)bs;
    while (len > 8) {
        if (*a != *b) {
            return 1;

amosr

int read_bool (char *p)
{
    static const uint64_t true_mask  = 0x00000000ffffffff;
    static const uint64_t true_bits  = 0x0000000065757274;
    static const uint64_t false_mask = 0x000000ffffffffff;
    static const uint64_t false_bits = 0x00000065736c6166;

    static const uint64_t to_lower = 0x2020202020202020;

    uint64_t next8 = *(uint64_t *)p | to_lower;

amosr

$ ls -lah asx.psv
-rw-r--r--  1 amos  staff    59G 13 Nov 18:07 asx.psv


$ time grep -v EntryError asx.psv > /dev/null

real	14m33.885s
user	14m10.081s
sys	0m22.390s