mirror of
https://github.com/urbit/shrub.git
synced 2024-11-24 13:06:09 +03:00
Use a bit-mapped patricia trie in nash
this is much faster than the world's worst hashtable, or will be when it actually works...
This commit is contained in:
parent
35ef2f2442
commit
7d9c363d65
15
Makefile
15
Makefile
@ -36,7 +36,7 @@ RM=rm -f
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CC=gcc
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CXX=g++
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CXXFLAGS=$(CFLAGS)
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CLD=g++ -O2 -g -L/usr/local/lib -L/opt/local/lib
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CLD=g++ -O0 -g -L/usr/local/lib -L/opt/local/lib
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YACC=bison -v -b$(GENERATED)/y
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LEX=lex
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@ -58,11 +58,12 @@ INCLUDE=include
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GENERATED=generated
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MDEFINES=-DU2_OS_$(OS) -DU2_OS_ENDIAN_$(ENDIAN) -D U2_LIB=\"$(LIB)\"
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CFLAGS= -O2 -g \
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CFLAGS= -O0 -g \
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-I/usr/local/include \
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-I/opt/local/include \
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-I$(INCLUDE) \
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-Ioutside/libuv/include \
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-Ioutside/bpt \
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-Ioutside/re2 \
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-Ioutside/cre2/src/src \
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-I $(GENERATED) \
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@ -564,6 +565,8 @@ LIBUV=outside/libuv/libuv.a
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LIBRE2=outside/re2/obj/libre2.a
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BPT_O=outside/bpt/bitmapped_patricia_tree.o
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all: $(BIN)/vere
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$(LIBUV):
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@ -577,9 +580,12 @@ $(CRE2_OFILES): outside/cre2/src/src/cre2.cpp outside/cre2/src/src/cre2.h $(LIBR
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$(V_OFILES) f/loom.o f/trac.o: include/v/vere.h
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$(BIN)/vere: $(LIBCRE) $(VERE_OFILES) $(LIBUV) $(LIBRE2)
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$(BPT_O): outside/bpt/bitmapped_patricia_tree.c
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$(CC) -g -O0 -o $@ -c $<
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$(BIN)/vere: $(LIBCRE) $(VERE_OFILES) $(LIBUV) $(LIBRE2) $(BPT_O)
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mkdir -p $(BIN)
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$(CLD) $(CLDOSFLAGS) -o $(BIN)/vere $(VERE_OFILES) $(LIBUV) $(LIBCRE) $(LIBRE2) $(LIBS)
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$(CLD) $(CLDOSFLAGS) -o $(BIN)/vere $(VERE_OFILES) $(LIBUV) $(LIBCRE) $(LIBRE2) $(BPT_O) $(LIBS)
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tags:
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ctags -R -f .tags --exclude=root
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@ -593,3 +599,4 @@ clean:
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distclean: clean
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$(MAKE) -C outside/libuv clean
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$(MAKE) -C outside/re2 clean
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rm $(BPT_O)
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87
f/nash.c
87
f/nash.c
@ -3,6 +3,7 @@
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** This file is in the public domain.
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*/
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#include "all.h"
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#include <bitmapped_patricia_tree.h>
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struct u2_nair {
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u2_noun key;
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@ -15,10 +16,11 @@ struct u2_buck {
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};
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struct u2_nash {
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c3_w cap_w;
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struct u2_buck* sto_u;
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bpt_t sto;
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};
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void u2_na_dump(struct u2_nash* nash);
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/* u2_na_make(): create a new nounhash-table.
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**
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** nashtables live in C memory and do not take refs.
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@ -26,10 +28,7 @@ struct u2_nash {
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struct u2_nash*
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u2_na_make()
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{
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struct u2_nash* nas_u = c3_malloc(sizeof(struct u2_nash));
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nas_u->cap_w = 521;
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nas_u->sto_u = calloc(nas_u->cap_w, sizeof(struct u2_buck));
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c3_assert(nas_u->sto_u);
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struct u2_nash* nas_u = calloc(1, sizeof(*nas_u));
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// fprintf(stderr, "[%%nash-make %p]\r\n", nas_u);
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return nas_u;
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}
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@ -39,11 +38,29 @@ u2_na_make()
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void
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u2_na_put(struct u2_nash* nash, u2_noun key, u2_noun val)
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{
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struct u2_buck* buc_u = &(nash->sto_u[u2_mug(key) % nash->cap_w]);
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struct u2_buck* buc_u = 0;
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struct u2_nair* nuu_u = 0;
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c3_w sot_w = 0;
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c3_w i = 0;
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struct u2_nair* nuu_u;
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c3_w sot_w;
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c3_w i;
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u2_noun tom = u2_mug(key);
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if ( !bpt_has_key(nash->sto, tom)) {
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bpt_t ots;
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buc_u = calloc(1, sizeof(*buc_u));
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ots = bpt_assoc(nash->sto, tom, buc_u);
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bpt_release(nash->sto);
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nash->sto = ots;
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#if 0
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fprintf(stderr, "[%%nash-sto %p %p]\r\n", nash->sto, tom);
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if (!bpt_has_key(nash->sto, tom)) {
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u2_na_dump(nash);
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assert(0);
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}
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#endif
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}
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buc_u = bpt_get(nash->sto, tom);
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if ( 0 == buc_u->con_w ) {
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c3_assert(buc_u->sto_u == 0);
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@ -69,11 +86,11 @@ u2_na_put(struct u2_nash* nash, u2_noun key, u2_noun val)
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nuu_u[sot_w].key = key;
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nuu_u[sot_w].val = val;
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buc_u->sto_u = nuu_u;
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#if 0
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fprintf(stderr, "[%%nash-put %p %p %d]\r\n",
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(void*)key, (void*)val, sot_w);
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#endif
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buc_u->sto_u = nuu_u;
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}
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/* u2_na_get(): get from a nounhash table
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@ -81,8 +98,15 @@ u2_na_put(struct u2_nash* nash, u2_noun key, u2_noun val)
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u2_weak
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u2_na_get(struct u2_nash* nash, u2_noun key)
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{
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struct u2_buck* buc_u = &(nash->sto_u[u2_mug(key) % nash->cap_w]);
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struct u2_buck* buc_u = 0;
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c3_w i;
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u2_noun tom = u2_mug(key);
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if ( !bpt_has_key(nash->sto, tom) ) {
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// fprintf(stderr, "[%%nash-get-none %p %p]\r\n", nash->sto, tom);
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return 0;
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}
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buc_u = bpt_get(nash->sto, tom);
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for(i = 0; i < buc_u->con_w; i++) {
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if (u2_sing(buc_u->sto_u[i].key, key) == u2_yes) {
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#if 0
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@ -95,21 +119,40 @@ u2_na_get(struct u2_nash* nash, u2_noun key)
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return 0;
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}
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static
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void
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_na_drop(bpt_key_t x, void* a, void* b)
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{
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struct u2_buck* buc = a;
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free(buc->sto_u);
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free(buc);
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}
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void
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_na_dump(bpt_key_t x, void* a, void* b)
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{
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struct u2_buck* buc = a;
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int i;
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fprintf(stderr, "[%%nash-dump %x ", x);
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for(i=0;i<buc->con_w;i++) {
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fprintf(stderr, "%x->%x%s", buc->sto_u[i].key, buc->sto_u[i].val,
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i+1==buc->con_w?"":" ");
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}
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fprintf(stderr, "]\r\n");
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}
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void u2_na_dump(struct u2_nash* nash)
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{
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if(nash->sto) bpt_for_mappings(nash->sto, _na_dump, 0);
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}
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/* u2_na_take(): destroy a nounhash table
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**/
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void
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u2_na_take(struct u2_nash* nash)
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{
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c3_w i;
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for(i=0; i < nash->cap_w; i++) {
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#if 0
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fprintf(stderr, "%s%d%s", nash->sto_u[i].con_w,
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0==i? "[%%nash-pop " :"",
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i+1==nash->cap_w? "]\r\n" :" ");
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#endif
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free(nash->sto_u[i].sto_u);
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}
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free(nash->sto_u);
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bpt_for_mappings(nash->sto, _na_drop, 0);
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bpt_release(nash->sto);
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free(nash);
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// fprintf(stderr, "[%%nash-take %p]\r\n", nash);
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}
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522
outside/bpt/bitmapped_patricia_tree.c
Normal file
522
outside/bpt/bitmapped_patricia_tree.c
Normal file
@ -0,0 +1,522 @@
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// -*- mode: c; coding: utf-8 -*- */
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//
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// Copyright 2010, 2011, Matthias Andreas Benkard.
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//
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//-----------------------------------------------------------------------------
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// This program is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Affero General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Affero General Public License for more details.
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//
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// You should have received a copy of the GNU Affero General Public License
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// along with this program. If not, see <http://www.gnu.org/licenses/>.
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//-----------------------------------------------------------------------------
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//
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// An implementation of a bitmapped Patricia tree.
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//// Purpose ////
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//
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// The idea is to use a locally mutable, bitmapped Patricia tree as a
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// variable binding store (i.e. environment) in compiled code. In this
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// way, there is no need for excessive copying when an independent
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// environment must be set up (such as when initiating the processing of
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// a new node in the search space). Instead, significant amounts of
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// structure can be shared between child and parent environments.
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//// Motivation ////
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//
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// 1. Patricia trees are very amenable to structure sharing.
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//
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// 2. Furthermore, big-endian Patricia trees are especially efficient
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// when indices are allocated sequentially, as is the case for
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// variables in code emitted by our compiler.
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//
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// 3. Finally, bitmapping improves the performance of copying because
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// copying an array is much cheaper than copying an equivalent branch
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// in a tree. As we need to shallow-copy the tree at potentially
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// each choice point, copying needs to be fast.
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#include <stdlib.h>
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#include <string.h>
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#include <assert.h>
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#include "bitmapped_patricia_tree.h"
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#ifndef BPT_EXPLICIT_CONFIGURATION
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#define CHUNK_LENGTH 5
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#define KEY_LENGTH 32
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#define OFFSET_MASK 0x1ffff //((1 << chunk_length) - 1)
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#define MAX_CHUNKS 7 //key_length / chunk_length + ((key_length % chunk_length == 0) ? 0 : 1)
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#define LAST_CHUNK_LENGTH 2 //key_length - ((max_chunks - 1) * chunk_length)
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#endif //!BPT_EXPLICIT_CONFIGURATION
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typedef struct bpt_nonempty *bpt_nonempty_t;
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typedef struct bpt_node *bpt_node_t;
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typedef struct bpt_leaf *bpt_leaf_t;
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struct bpt {
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enum bpt_tag tag;
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int refcount;
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bool mutable;
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bpt_key_t prefix;
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};
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struct bpt_leaf {
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struct bpt bpt; // poor man's inheritance
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void *value;
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#ifdef BPT_ENABLE_DEALLOC_HOOKS
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void (*dealloc_hook)(bpt_key_t, void *); // not actually used anywhere in client code
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#endif
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};
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struct bpt_node {
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struct bpt bpt; // poor man's inheritance
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unsigned int branching_chunk;
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bpt_key_bitmask_t bitmask;
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bpt_t *children;
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};
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// Forward declarations.
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void init_bpt_leaf(bpt_t leaf, bpt_key_t key, void *value);
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bpt_t bpt_make_leaf(bpt_key_t key, void *value);
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// Boilerplate definitions.
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void bpt_retain0(bpt_t bpt, void *user_data) {
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bpt_retain(bpt);
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}
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void bpt_seal0(bpt_t bpt, void *user_data) {
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bpt_seal(bpt);
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}
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void bpt_release0(bpt_t bpt, void *user_data) {
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bpt_release(bpt);
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}
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// Implementation.
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void init_bpt_leaf(bpt_t a_leaf, bpt_key_t key, void *value) {
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bpt_leaf_t leaf = (bpt_leaf_t)a_leaf;
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leaf->bpt.tag = BPT_LEAF;
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leaf->bpt.mutable = true;
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leaf->bpt.prefix = key;
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leaf->value = value;
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#ifdef BPT_ENABLE_DEALLOC_HOOKS
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leaf->dealloc_hook = NULL;
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#endif
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leaf->bpt.refcount = 1;
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}
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void init_bpt_node(bpt_node_t node, bpt_key_t prefix, unsigned int branching_chunk) {
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node->bpt.tag = BPT_INNER_NODE;
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node->bpt.mutable = true;
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node->bpt.prefix = prefix;
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node->branching_chunk = branching_chunk;
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node->bitmask = 0;
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node->children = NULL;
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node->bpt.refcount = 1;
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}
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bpt_t bpt_make_leaf(bpt_key_t key, void *value) {
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bpt_leaf_t leaf = malloc(sizeof *leaf);
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init_bpt_leaf((bpt_t)leaf, key, value);
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return (bpt_t)leaf;
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}
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bpt_node_t bpt_make_node(bpt_key_t prefix, unsigned int branching_chunk) {
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bpt_node_t node = malloc(sizeof *node);
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init_bpt_node(node, prefix, branching_chunk);
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return node;
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}
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static inline unsigned int bpt_number_of_leading_zeros(bpt_key_t x);
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static inline unsigned int bpt_number_of_trailing_zeros(bpt_key_t x);
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static inline unsigned int bpt_popcount(bpt_key_bitmask_t key);
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static unsigned int bpt_compute_child_index(bpt_key_bitmask_t bitmask, unsigned int child_number);
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static inline uint_fast8_t bpt_offset_of_key(bpt_key_t key, unsigned int branching_chunk);
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static bpt_key_t bpt_prefix_of_key(bpt_key_t key, unsigned int branching_chunk);
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static inline unsigned int bpt_branching_chunk(bpt_t bpt);
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static unsigned int bpt_find_diverging_chunk(bpt_key_t key1, bpt_key_t key2);
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static void bpt_for_children(bpt_t bpt, void (*thunk)(bpt_t, void*), void *user_data);
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static void bpt_for_children(bpt_t bpt, void (*thunk)(bpt_t, void*), void *user_data) {
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if (bpt && bpt->tag == BPT_INNER_NODE) {
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bpt_node_t b = (bpt_node_t)bpt;
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bpt_t *iter = b->children;
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bpt_t *children_end = b->children + bpt_popcount(b->bitmask);
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while (iter < children_end) {
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thunk(*iter, user_data);
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iter++;
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}
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}
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}
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void *bpt_get(bpt_t bpt, bpt_key_t key) {
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void **pointer = bpt_get_pointer(bpt, key);
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if (pointer) {
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return *pointer;
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} else {
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return NULL;
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}
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}
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bpt_leaf_t bpt_get_leaf(bpt_t bpt, bpt_key_t key)
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{
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if (!bpt) {
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return NULL;
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} else if (bpt->tag == BPT_LEAF) {
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bpt_leaf_t b = (bpt_leaf_t)bpt;
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if (bpt->prefix == key) {
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return b;
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} else {
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return NULL;
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}
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} else {
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bpt_node_t b = (bpt_node_t)bpt;
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int child_number = bpt_offset_of_key(key, b->branching_chunk);
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if ((1 << child_number) & b->bitmask) {
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int child_index = bpt_compute_child_index(b->bitmask, child_number);
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return bpt_get_leaf(b->children[child_index], key);
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} else {
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return NULL;
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}
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}
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}
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void **bpt_get_pointer(bpt_t bpt, bpt_key_t key)
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{
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bpt_leaf_t leaf = bpt_get_leaf(bpt, key);
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if (!leaf) {
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return NULL;
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} else {
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return &leaf->value;
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}
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}
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bool bpt_has_key(bpt_t bpt, bpt_key_t key) {
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return (bpt_get_leaf(bpt, key) != NULL);
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}
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bpt_t bpt_assoc(bpt_t bpt, bpt_key_t key, void *value) {
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if (!bpt) {
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return (bpt_t)bpt_make_leaf(key, value);
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} else {
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bpt_key_t prefix = bpt->prefix;
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if (bpt_prefix_of_key(key, bpt_branching_chunk(bpt)) != prefix) {
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unsigned int diverging_chunk = bpt_find_diverging_chunk(key, prefix);
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bpt_key_t my_number_in_parent = bpt_offset_of_key(prefix, diverging_chunk);
|
||||
bpt_key_t their_number_in_parent = bpt_offset_of_key(key, diverging_chunk);
|
||||
bpt_node_t new_node = bpt_make_node(bpt_prefix_of_key(prefix, diverging_chunk), diverging_chunk);
|
||||
new_node->bitmask = (1 << my_number_in_parent) | (1 << their_number_in_parent);
|
||||
new_node->children = malloc(sizeof (*new_node->children) * 2);
|
||||
if (my_number_in_parent < their_number_in_parent) {
|
||||
new_node->children[0] = bpt;
|
||||
new_node->children[1] = bpt_make_leaf(key, value);
|
||||
} else {
|
||||
new_node->children[0] = bpt_make_leaf(key, value);
|
||||
new_node->children[1] = bpt;
|
||||
}
|
||||
bpt_retain(bpt);
|
||||
return (bpt_t)new_node;
|
||||
} else {
|
||||
if (bpt->tag == BPT_LEAF) {
|
||||
bpt_leaf_t b = (bpt_leaf_t)bpt;
|
||||
if (bpt->mutable) {
|
||||
b->value = value;
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else {
|
||||
return (bpt_t)bpt_make_leaf(key, value);
|
||||
}
|
||||
} else {
|
||||
bpt_node_t b = (bpt_node_t)bpt;
|
||||
uint_fast8_t child_number = bpt_offset_of_key(key, b->branching_chunk);
|
||||
unsigned int child_index = bpt_compute_child_index(b->bitmask, child_number);
|
||||
if ((1 << child_number) & b->bitmask) {
|
||||
// We already have a child to pass the value to. Do that.
|
||||
bpt_t child = b->children[child_index];
|
||||
bpt_t new_child = bpt_assoc(child, key, value);
|
||||
if (new_child == child) {
|
||||
bpt_release(child);
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else {
|
||||
if (bpt->mutable) {
|
||||
bpt_release(child);
|
||||
b->children[child_index] = new_child;
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else {
|
||||
bpt_node_t new_node = malloc(sizeof *new_node);
|
||||
*new_node = *b;
|
||||
new_node->bpt.refcount = 1;
|
||||
new_node->bpt.mutable = true;
|
||||
unsigned int number_of_children = bpt_popcount(b->bitmask);
|
||||
size_t size_of_child_array = sizeof (*new_node->children) * number_of_children;
|
||||
new_node->children = malloc(size_of_child_array);
|
||||
memcpy(new_node->children, b->children, size_of_child_array);
|
||||
new_node->children[child_index] = new_child;
|
||||
// Retain the children copied into the new node.
|
||||
bpt_for_children((bpt_t)new_node, bpt_retain0, NULL);
|
||||
bpt_release(new_child);
|
||||
return (bpt_t)new_node;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
// Create a new child.
|
||||
unsigned int number_of_children = bpt_popcount(b->bitmask);
|
||||
size_t new_size_of_child_array = sizeof (*b->children) * (number_of_children + 1);
|
||||
if (bpt->mutable) {
|
||||
b->children = realloc(b->children, new_size_of_child_array);
|
||||
memmove(b->children + child_index + 1, b->children + child_index, sizeof (*b->children) * (number_of_children - child_index));
|
||||
b->children[child_index] = bpt_make_leaf(key, value);
|
||||
b->bitmask |= 1 << child_number;
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else {
|
||||
bpt_t *new_children = malloc(new_size_of_child_array);
|
||||
memcpy(new_children, b->children, sizeof (*b->children) * child_index);
|
||||
memcpy(new_children + child_index + 1,
|
||||
b->children + child_index,
|
||||
sizeof (*b->children) * (number_of_children - child_index));
|
||||
new_children[child_index] = bpt_make_leaf(key, value);
|
||||
bpt_node_t new_node = bpt_make_node(b->bpt.prefix, b->branching_chunk);
|
||||
new_node->children = new_children;
|
||||
new_node->bitmask = b->bitmask | (1 << child_number);
|
||||
// Retain the children copied into the new node.
|
||||
bpt_for_children(bpt, bpt_retain0, NULL);
|
||||
return (bpt_t)new_node;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
bpt_t bpt_dissoc(bpt_t bpt, bpt_key_t key) {
|
||||
if (!bpt || (bpt_prefix_of_key(key, bpt_branching_chunk(bpt)) != bpt->prefix)) {
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else if (bpt->tag == BPT_LEAF) {
|
||||
// Key matches.
|
||||
return NULL;
|
||||
} else {
|
||||
// Prefix matches.
|
||||
bpt_node_t b = (bpt_node_t)bpt;
|
||||
uint_fast8_t child_number = bpt_offset_of_key(key, b->branching_chunk);
|
||||
if ((1 << child_number) & b->bitmask) {
|
||||
unsigned int child_index = bpt_compute_child_index(b->bitmask, child_number);
|
||||
bpt_t child = b->children[child_index];
|
||||
bpt_t new_child = bpt_dissoc(child, key);
|
||||
if (new_child == child) {
|
||||
bpt_release(child);
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else {
|
||||
unsigned int number_of_children = bpt_popcount(b->bitmask);
|
||||
if (!new_child && number_of_children == 2) {
|
||||
// When there is only a single child left, we replace ourselves
|
||||
// with that child.
|
||||
bpt_t remaining_child = b->children[1-child_index];
|
||||
bpt_retain(remaining_child);
|
||||
return remaining_child;
|
||||
} else if (bpt->mutable) {
|
||||
bpt_release(child);
|
||||
if (!new_child) {
|
||||
// We don't reallocate the array because it wouldn't really
|
||||
// gain us anything (except maybe non-confusion of a
|
||||
// conservative GC).
|
||||
memmove(b->children + child_index, b->children + child_index + 1, sizeof(*b->children) * (number_of_children - child_index - 1));
|
||||
b->bitmask &= ~(1 << child_number);
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
} else {
|
||||
b->children[child_index] = new_child;
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
}
|
||||
} else {
|
||||
// If all else fails, allocate a new node.
|
||||
bpt_t *new_children;
|
||||
bpt_key_bitmask_t bitmask;
|
||||
if (!new_child) {
|
||||
new_children = malloc((sizeof *new_children) * (number_of_children - 1));
|
||||
memcpy(new_children, b->children, sizeof (*b->children) * child_index);
|
||||
memcpy(new_children + child_index,
|
||||
b->children + child_index + 1,
|
||||
sizeof (*b->children) * (number_of_children - child_index - 1));
|
||||
bitmask = b->bitmask & ~(1 << child_number);
|
||||
} else {
|
||||
new_children = malloc((sizeof *new_children) * number_of_children);
|
||||
memcpy(new_children, b->children, sizeof (*b->children) * number_of_children);
|
||||
new_children[child_index] = new_child;
|
||||
bitmask = b->bitmask;
|
||||
}
|
||||
bpt_node_t new_node = bpt_make_node(b->bpt.prefix, b->branching_chunk);
|
||||
new_node->children = new_children;
|
||||
new_node->bitmask = bitmask;
|
||||
// Retain the children copied into the new node.
|
||||
bpt_for_children((bpt_t)new_node, bpt_retain0, NULL);
|
||||
bpt_release(new_child);
|
||||
return (bpt_t)new_node;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
bpt_retain(bpt);
|
||||
return bpt;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
void bpt_seal(bpt_t bpt) {
|
||||
if (bpt) {
|
||||
if (bpt->mutable) {
|
||||
bpt->mutable = false;
|
||||
if (bpt->tag == BPT_INNER_NODE) {
|
||||
bpt_for_children(bpt, bpt_seal0, NULL);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/////////////// Helper functions ///////////////
|
||||
static unsigned int bpt_compute_child_index(bpt_key_bitmask_t bitmask, unsigned int child_number) {
|
||||
// Compute the sparse array index given a flat array index.
|
||||
return bpt_popcount(bitmask & ((1 << child_number) - 1));
|
||||
}
|
||||
|
||||
static inline uint_fast8_t bpt_offset_of_key(bpt_key_t key, unsigned int chunk_number) {
|
||||
// Little-enidan:
|
||||
//return (key >> (chunk_number * CHUNK_LENGTH)) & OFFSET_MASK;
|
||||
// Big-endian:
|
||||
int shift = 0;
|
||||
if (chunk_number <= MAX_CHUNKS - 2) {
|
||||
shift += LAST_CHUNK_LENGTH;
|
||||
}
|
||||
if (chunk_number <= MAX_CHUNKS - 3) {
|
||||
shift += ((MAX_CHUNKS - 2 - chunk_number) * CHUNK_LENGTH);
|
||||
}
|
||||
return (key >> shift) & (chunk_number == MAX_CHUNKS - 1 ? ((1 << LAST_CHUNK_LENGTH) - 1) : OFFSET_MASK);
|
||||
}
|
||||
|
||||
static bpt_key_t bpt_prefix_of_key(bpt_key_t key, unsigned int chunk_number) {
|
||||
if (chunk_number == MAX_CHUNKS) {
|
||||
return key;
|
||||
} else {
|
||||
// Little-endian:
|
||||
//return key & ((1 << (chunk_number * CHUNK_LENGTH)) - 1)
|
||||
// Big-endian:
|
||||
return key & (((1 << (chunk_number * CHUNK_LENGTH)) - 1) << (KEY_LENGTH - (chunk_number * CHUNK_LENGTH)));
|
||||
}
|
||||
}
|
||||
|
||||
static inline unsigned int bpt_branching_chunk(bpt_t bpt) {
|
||||
assert(bpt);
|
||||
if (bpt->tag == BPT_LEAF) {
|
||||
return MAX_CHUNKS;
|
||||
} else {
|
||||
return ((bpt_node_t)bpt)->branching_chunk;
|
||||
}
|
||||
}
|
||||
|
||||
static inline unsigned int bpt_popcount(bpt_key_bitmask_t x) {
|
||||
return __builtin_popcountll(x);
|
||||
}
|
||||
|
||||
static inline unsigned int bpt_number_of_leading_zeros(bpt_key_t x) {
|
||||
return __builtin_clzll(x);
|
||||
}
|
||||
|
||||
static inline unsigned int bpt_number_of_trailing_zeros(bpt_key_t x) {
|
||||
return __builtin_ctzll(x);
|
||||
}
|
||||
|
||||
static unsigned int bpt_find_diverging_chunk(bpt_key_t a, bpt_key_t b) {
|
||||
// Little-endian:
|
||||
//return bpt_number_of_trailing_zeros(a ^ b) / CHUNK_LENGTH;
|
||||
// Big-endian:
|
||||
return bpt_number_of_leading_zeros(a ^ b) / CHUNK_LENGTH;
|
||||
}
|
||||
|
||||
void bpt_retain(bpt_t bpt) {
|
||||
if (bpt) {
|
||||
__sync_fetch_and_add(&bpt->refcount, 1);
|
||||
}
|
||||
}
|
||||
|
||||
void bpt_release(bpt_t bpt) {
|
||||
if (bpt) {
|
||||
if (__sync_sub_and_fetch(&bpt->refcount, 1) == 0) {
|
||||
bpt_dealloc(bpt);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void bpt_dealloc(bpt_t bpt) {
|
||||
if (bpt) {
|
||||
if (bpt->tag == BPT_LEAF) {
|
||||
bpt_leaf_t b = (bpt_leaf_t)bpt;
|
||||
#ifdef BPT_ENABLE_DEALLOC_HOOKS
|
||||
if (b->dealloc_hook) {
|
||||
b->dealloc_hook(b->bpt.prefix, b->value);
|
||||
}
|
||||
#endif
|
||||
free(b);
|
||||
} else {
|
||||
bpt_node_t b = (bpt_node_t)bpt;
|
||||
bpt_for_children(bpt, bpt_release0, NULL);
|
||||
free(b->children);
|
||||
free(b);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#ifdef BPT_ENABLE_DEALLOC_HOOKS
|
||||
void bpt_leaf_set_dealloc_hook(bpt_leaf_t bpt, void (*hook)(bpt_key_t, void*)) {
|
||||
if (bpt) {
|
||||
bpt->dealloc_hook = hook;
|
||||
}
|
||||
}
|
||||
|
||||
void bpt_set_dealloc_hook(bpt_t bpt, bpt_key_t key, void (*hook)(bpt_key_t, void*)) {
|
||||
bpt_leaf_set_dealloc_hook(bpt_get_leaf(bpt, key), hook);
|
||||
}
|
||||
#endif
|
||||
|
||||
|
||||
|
||||
/* Utilities */
|
||||
struct bpt_for_mappings_closure_data {
|
||||
void (*thunk)(bpt_key_t, void*, void*);
|
||||
void *user_data;
|
||||
};
|
||||
static void bpt_for_mappings_iter(bpt_t bpt, void *closure_data_) {
|
||||
struct bpt_for_mappings_closure_data *closure_data = closure_data_;
|
||||
if (bpt->tag == BPT_LEAF) {
|
||||
bpt_leaf_t leaf = (bpt_leaf_t)bpt;
|
||||
closure_data->thunk(bpt->prefix, leaf->value, closure_data->user_data);
|
||||
} else {
|
||||
bpt_for_children(bpt, bpt_for_mappings_iter, closure_data);
|
||||
}
|
||||
}
|
||||
void bpt_for_mappings(bpt_t bpt, void (*thunk)(bpt_key_t, void*, void*), void *user_data) {
|
||||
struct bpt_for_mappings_closure_data closure_data =
|
||||
{ .user_data = user_data, .thunk = thunk };
|
||||
|
||||
bpt_for_mappings_iter(bpt, &closure_data);
|
||||
}
|
71
outside/bpt/bitmapped_patricia_tree.h
Normal file
71
outside/bpt/bitmapped_patricia_tree.h
Normal file
@ -0,0 +1,71 @@
|
||||
// -*- mode: c; coding: utf-8 -*- */
|
||||
//
|
||||
// Copyright 2010, 2011, Matthias Andreas Benkard.
|
||||
//
|
||||
//-----------------------------------------------------------------------------
|
||||
// This program is free software: you can redistribute it and/or modify
|
||||
// it under the terms of the GNU Affero General Public License as published by
|
||||
// the Free Software Foundation, either version 3 of the License, or
|
||||
// (at your option) any later version.
|
||||
//
|
||||
// This program is distributed in the hope that it will be useful,
|
||||
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
// GNU Affero General Public License for more details.
|
||||
//
|
||||
// You should have received a copy of the GNU Affero General Public License
|
||||
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
//-----------------------------------------------------------------------------
|
||||
//
|
||||
|
||||
// An implementation of a bitmapped Patricia tree.
|
||||
|
||||
#ifndef __BITMAPPED_PATRICIA_TREE_H
|
||||
#define __BITMAPPED_PATRICIA_TREE_H
|
||||
|
||||
#include <stdbool.h>
|
||||
#include <stdint.h>
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define BPT_ENABLE_DEALLOC_HOOKS 1
|
||||
|
||||
#ifdef BPT_EXPLICIT_CONFIGURATION
|
||||
typedef BPT_KEY_T bpt_key_t;
|
||||
typedef BPT_KEY_BITMASK_T bpt_key_bitmask_t;
|
||||
#else
|
||||
typedef int32_t bpt_key_t;
|
||||
typedef int32_t bpt_key_bitmask_t;
|
||||
#endif //!BPT_EXPLICIT_CONFIGURATION
|
||||
|
||||
enum bpt_tag {
|
||||
BPT_LEAF,
|
||||
BPT_INNER_NODE
|
||||
};
|
||||
|
||||
struct bpt;
|
||||
typedef struct bpt *bpt_t;
|
||||
|
||||
// Base functionality.
|
||||
void *bpt_get(bpt_t bpt, bpt_key_t key);
|
||||
bool bpt_has_key(bpt_t bpt, bpt_key_t key);
|
||||
void **bpt_get_pointer(bpt_t bpt, bpt_key_t key);
|
||||
bpt_t bpt_assoc(bpt_t bpt, bpt_key_t key, void *item);
|
||||
bpt_t bpt_dissoc(bpt_t bpt, bpt_key_t key);
|
||||
void bpt_retain(bpt_t bpt);
|
||||
void bpt_release(bpt_t bpt);
|
||||
void bpt_dealloc(bpt_t bpt);
|
||||
void bpt_seal(bpt_t bpt);
|
||||
|
||||
// Utilities
|
||||
void bpt_for_mappings(bpt_t bpt, void (*thunk)(bpt_key_t, void*, void*), void *user_data);
|
||||
#ifdef BPT_ENABLE_DEALLOC_HOOKS
|
||||
void bpt_set_dealloc_hook(bpt_t bpt, bpt_key_t key, void (*hook)(bpt_key_t key, void* value));
|
||||
#endif
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
#endif
|
Loading…
Reference in New Issue
Block a user