deb-libisal/igzip/proc_heap_base.c
Greg Tucker ec6e5de665 igzip: Move build_heap base functions to own file
Change-Id: I0161cd65c71df00fadad9dd69e207e9fb29a54ef
Signed-off-by: Greg Tucker <greg.b.tucker@intel.com>
2017-03-30 18:20:09 -07:00

85 lines
2.8 KiB
C

/**********************************************************************
Copyright(c) 2011-2017 Intel Corporation All rights reserved.
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#include "igzip_lib.h"
#include "huff_codes.h"
void inline heapify(uint64_t * heap, uint64_t heap_size, uint64_t index)
{
uint64_t child = 2 * index, tmp;
while (child <= heap_size) {
child = (heap[child] <= heap[child + 1]) ? child : child + 1;
if (heap[index] > heap[child]) {
tmp = heap[index];
heap[index] = heap[child];
heap[child] = tmp;
index = child;
child = 2 * index;
} else
break;
}
}
void build_heap(uint64_t * heap, uint64_t heap_size)
{
uint64_t i;
heap[heap_size + 1] = -1;
for (i = heap_size / 2; i > 0; i--)
heapify(heap, heap_size, i);
}
uint32_t build_huff_tree(struct heap_tree *heap_space, uint64_t heap_size, uint64_t node_ptr)
{
uint64_t *heap = (uint64_t *) heap_space;
uint64_t h1, h2;
while (heap_size > 1) {
h1 = heap[1];
heap[1] = heap[heap_size];
heap[heap_size--] = -1;
heapify(heap, heap_size, 1);
h2 = heap[1];
heap[1] = ((h1 + h2) & ~0xFFFFull) | node_ptr;
heapify(heap, heap_size, 1);
*(uint16_t *) (&heap[node_ptr]) = h1;
*(uint16_t *) (&heap[node_ptr - 1]) = h2;
node_ptr -= 2;
}
h1 = heap[1];
*(uint16_t *) (&heap[node_ptr]) = h1;
return node_ptr;
}