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author | Kartik K. Agaram <vc@akkartik.com> | 2016-02-25 17:17:20 -0800 |
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committer | Kartik K. Agaram <vc@akkartik.com> | 2016-02-25 17:17:20 -0800 |
commit | dcc060c7d4ef56b978beb34ddce8d8ffcec94fa6 (patch) | |
tree | 7cbb9cd1d8544c7c6c65725fa195ca3821b04b07 /html/077hash.cc.html | |
parent | 0f5a2f4e21046e319ce0fadec32cc5e89d2f4620 (diff) | |
download | mu-dcc060c7d4ef56b978beb34ddce8d8ffcec94fa6.tar.gz |
2706 - update html
Diffstat (limited to 'html/077hash.cc.html')
-rw-r--r-- | html/077hash.cc.html | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/html/077hash.cc.html b/html/077hash.cc.html new file mode 100644 index 00000000..d223be71 --- /dev/null +++ b/html/077hash.cc.html @@ -0,0 +1,431 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> +<html> +<head> +<meta http-equiv="content-type" content="text/html; charset=UTF-8"> +<title>Mu - 077hash.cc</title> +<meta name="Generator" content="Vim/7.4"> +<meta name="plugin-version" content="vim7.4_v1"> +<meta name="syntax" content="cpp"> +<meta name="settings" content="use_css,pre_wrap,no_foldcolumn,expand_tabs,prevent_copy="> +<meta name="colorscheme" content="minimal"> +<style type="text/css"> +<!-- +pre { white-space: pre-wrap; font-family: monospace; color: #eeeeee; background-color: #080808; } +body { font-family: monospace; color: #eeeeee; background-color: #080808; } +* { font-size: 1.05em; } +.traceContains { color: #008000; } +.cSpecial { color: #008000; } +.CommentedCode { color: #6c6c6c; } +.Comment { color: #9090ff; } +.Delimiter { color: #a04060; } +.Special { color: #ff6060; } +.Identifier { color: #804000; } +.Constant { color: #00a0a0; } +--> +</style> + +<script type='text/javascript'> +<!-- + +--> +</script> +</head> +<body> +<pre id='vimCodeElement'> +<span class="Comment">// A universal hash function that can handle objects of any type.</span> +<span class="Comment">//</span> +<span class="Comment">// The way it's currently implemented, two objects will have the same hash if</span> +<span class="Comment">// all their non-address fields (all the way down) expand to the same sequence</span> +<span class="Comment">// of scalar values. In particular, a container with all zero addresses hashes</span> +<span class="Comment">// to 0. Hopefully this won't be an issue because we are usually hashing</span> +<span class="Comment">// objects of a single type in any given hash table.</span> +<span class="Comment">//</span> +<span class="Comment">// Based on <a href="http://burtleburtle.net/bob/hash/hashfaq.html">http://burtleburtle.net/bob/hash/hashfaq.html</a></span> + +<span class="Delimiter">:(before "End Primitive Recipe Declarations")</span> +HASH<span class="Delimiter">,</span> +<span class="Delimiter">:(before "End Primitive Recipe Numbers")</span> +put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">"hash"</span><span class="Delimiter">,</span> HASH<span class="Delimiter">);</span> +<span class="Delimiter">:(before "End Primitive Recipe Checks")</span> +case HASH: <span class="Delimiter">{</span> + if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span> + raise_error << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"'hash' takes exactly one ingredient rather than '"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> + <span class="Delimiter">}</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> +<span class="Delimiter">}</span> +<span class="Delimiter">:(before "End Primitive Recipe Implementations")</span> +case HASH: <span class="Delimiter">{</span> + reagent input = current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span> <span class="Comment">// copy</span> + products<span class="Delimiter">.</span>resize<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span> + products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>push_back<span class="Delimiter">(</span>hash<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">,</span> input<span class="Delimiter">));</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +<span class="Comment">//: in all the code below, the intermediate results of hashing are threaded through 'h'</span> + +<span class="Delimiter">:(code)</span> +size_t hash<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> +<span class="CommentedCode">//? cerr << debug_string(r) << '\n';</span> + canonize<span class="Delimiter">(</span>r<span class="Delimiter">);</span> + if <span class="Delimiter">(</span>is_mu_string<span class="Delimiter">(</span>r<span class="Delimiter">))</span> <span class="Comment">// optimization</span> + <span class="Identifier">return</span> hash_mu_string<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> + else if <span class="Delimiter">(</span>is_mu_address<span class="Delimiter">(</span>r<span class="Delimiter">))</span> + <span class="Identifier">return</span> hash_mu_address<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> + else if <span class="Delimiter">(</span>is_mu_scalar<span class="Delimiter">(</span>r<span class="Delimiter">))</span> + <span class="Identifier">return</span> hash_mu_scalar<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> + else if <span class="Delimiter">(</span>is_mu_array<span class="Delimiter">(</span>r<span class="Delimiter">))</span> + <span class="Identifier">return</span> hash_mu_array<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> + else if <span class="Delimiter">(</span>is_mu_container<span class="Delimiter">(</span>r<span class="Delimiter">))</span> + <span class="Identifier">return</span> hash_mu_container<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> + else if <span class="Delimiter">(</span>is_mu_exclusive_container<span class="Delimiter">(</span>r<span class="Delimiter">))</span> + <span class="Identifier">return</span> hash_mu_exclusive_container<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> + assert<span class="Delimiter">(</span><span class="Constant">false</span><span class="Delimiter">);</span> +<span class="Delimiter">}</span> + +size_t hash_mu_scalar<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + double input = is_literal<span class="Delimiter">(</span>r<span class="Delimiter">)</span> ? r<span class="Delimiter">.</span>value : get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span> + <span class="Identifier">return</span> hash_iter<span class="Delimiter">(</span>h<span class="Delimiter">,</span> static_cast<size_t><span class="Delimiter">(</span>input<span class="Delimiter">));</span> +<span class="Delimiter">}</span> + +size_t hash_mu_address<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + if <span class="Delimiter">(</span>r<span class="Delimiter">.</span>value == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Identifier">return</span> <span class="Constant">0</span><span class="Delimiter">;</span> + r<span class="Delimiter">.</span>value = get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span> + drop_from_type<span class="Delimiter">(</span>r<span class="Delimiter">,</span> <span class="Constant">"address"</span><span class="Delimiter">);</span> + if <span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>name == <span class="Constant">"shared"</span><span class="Delimiter">)</span> <span class="Delimiter">{</span> + ++r<span class="Delimiter">.</span>value<span class="Delimiter">;</span> + drop_from_type<span class="Delimiter">(</span>r<span class="Delimiter">,</span> <span class="Constant">"shared"</span><span class="Delimiter">);</span> + <span class="Delimiter">}</span> + <span class="Identifier">return</span> hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span> +<span class="Delimiter">}</span> + +size_t hash_mu_string<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + string input = read_mu_string<span class="Delimiter">(</span>get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">));</span> + for <span class="Delimiter">(</span>long long int i = <span class="Constant">0</span><span class="Delimiter">;</span> i < SIZE<span class="Delimiter">(</span>input<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span> + h = hash_iter<span class="Delimiter">(</span>h<span class="Delimiter">,</span> static_cast<size_t><span class="Delimiter">(</span>input<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">)));</span> +<span class="CommentedCode">//? cerr << i << ": " << h << '\n';</span> + <span class="Delimiter">}</span> + <span class="Identifier">return</span> h<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +size_t hash_mu_array<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + long long int size = get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span> + reagent elem = r<span class="Delimiter">;</span> + delete elem<span class="Delimiter">.</span>type<span class="Delimiter">;</span> + elem<span class="Delimiter">.</span>type = new type_tree<span class="Delimiter">(</span>*array_element<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">));</span> + for <span class="Delimiter">(</span>long long int i=<span class="Constant">0</span><span class="Delimiter">,</span> address = r<span class="Delimiter">.</span>value+<span class="Constant">1</span><span class="Delimiter">;</span> i < size<span class="Delimiter">;</span> ++i<span class="Delimiter">,</span> address += size_of<span class="Delimiter">(</span>elem<span class="Delimiter">))</span> <span class="Delimiter">{</span> + reagent tmp = elem<span class="Delimiter">;</span> + tmp<span class="Delimiter">.</span>value = address<span class="Delimiter">;</span> + h = hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> tmp<span class="Delimiter">);</span> +<span class="CommentedCode">//? cerr << i << " (" << address << "): " << h << '\n';</span> + <span class="Delimiter">}</span> + <span class="Identifier">return</span> h<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +bool is_mu_container<span class="Delimiter">(</span>const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + if <span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Identifier">return</span> <span class="Constant">false</span><span class="Delimiter">;</span> + type_info& info = get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span> + <span class="Identifier">return</span> info<span class="Delimiter">.</span>kind == CONTAINER<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +size_t hash_mu_container<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + assert<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span> + type_info& info = get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span> + long long int address = r<span class="Delimiter">.</span>value<span class="Delimiter">;</span> + long long int offset = <span class="Constant">0</span><span class="Delimiter">;</span> + for <span class="Delimiter">(</span>long long int i = <span class="Constant">0</span><span class="Delimiter">;</span> i < SIZE<span class="Delimiter">(</span>info<span class="Delimiter">.</span>elements<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span> + reagent element = element_type<span class="Delimiter">(</span>r<span class="Delimiter">,</span> i<span class="Delimiter">);</span> + if <span class="Delimiter">(</span>has_property<span class="Delimiter">(</span>element<span class="Delimiter">,</span> <span class="Constant">"ignore-for-hash"</span><span class="Delimiter">))</span> <span class="Identifier">continue</span><span class="Delimiter">;</span> + element<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>address+offset<span class="Delimiter">);</span> + h = hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> element<span class="Delimiter">);</span> +<span class="CommentedCode">//? cerr << i << ": " << h << '\n';</span> + offset += size_of<span class="Delimiter">(</span>info<span class="Delimiter">.</span>elements<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span>type<span class="Delimiter">);</span> + <span class="Delimiter">}</span> + <span class="Identifier">return</span> h<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +bool is_mu_exclusive_container<span class="Delimiter">(</span>const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + if <span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Identifier">return</span> <span class="Constant">false</span><span class="Delimiter">;</span> + type_info& info = get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span> + <span class="Identifier">return</span> info<span class="Delimiter">.</span>kind == EXCLUSIVE_CONTAINER<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +size_t hash_mu_exclusive_container<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> const reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span> + assert<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span> + long long int tag = get<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span> + reagent variant = variant_type<span class="Delimiter">(</span>r<span class="Delimiter">,</span> tag<span class="Delimiter">);</span> + <span class="Comment">// todo: move this error to container definition time</span> + if <span class="Delimiter">(</span>has_property<span class="Delimiter">(</span>variant<span class="Delimiter">,</span> <span class="Constant">"ignore-for-hash"</span><span class="Delimiter">))</span> + raise_error << get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> r<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">).</span>name << <span class="Constant">": /ignore-for-hash won't work in exclusive containers</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span> + variant<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>r<span class="Delimiter">.</span>value + <span class="Comment">/*</span><span class="Comment">skip tag</span><span class="Comment">*/</span><span class="Constant">1</span><span class="Delimiter">);</span> + h = hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> variant<span class="Delimiter">);</span> + <span class="Identifier">return</span> h<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +size_t hash_iter<span class="Delimiter">(</span>size_t h<span class="Delimiter">,</span> size_t input<span class="Delimiter">)</span> <span class="Delimiter">{</span> + h += input<span class="Delimiter">;</span> + h += <span class="Delimiter">(</span>h<<<span class="Constant">10</span><span class="Delimiter">);</span> + h ^= <span class="Delimiter">(</span>h>><span class="Constant">6</span><span class="Delimiter">);</span> + + h += <span class="Delimiter">(</span>h<<<span class="Constant">3</span><span class="Delimiter">);</span> + h ^= <span class="Delimiter">(</span>h>><span class="Constant">11</span><span class="Delimiter">);</span> + h += <span class="Delimiter">(</span>h<<<span class="Constant">15</span><span class="Delimiter">);</span> + <span class="Identifier">return</span> h<span class="Delimiter">;</span> +<span class="Delimiter">}</span> + +<span class="Delimiter">:(scenario hash_container_checks_all_elements)</span> +container foo [ + x:number + y:character +] +recipe main [ + <span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a + <span class="Constant">3</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo + reply-unless <span class="Constant">3</span>:number + <span class="Constant">4</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">98</span>/a + <span class="Constant">6</span>:number<span class="Special"> <- </span>hash <span class="Constant">4</span>:foo + reply-unless <span class="Constant">6</span>:number + <span class="Constant">7</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">3</span>:number<span class="Delimiter">,</span> <span class="Constant">6</span>:number +] +<span class="Comment"># hash on containers includes all elements</span> +<span class="traceContains">+mem: storing 0 in location 7</span> + +<span class="Delimiter">:(scenario hash_exclusive_container_checks_all_elements)</span> +exclusive-container foo [ + x:bar + y:number +] +container bar [ + a:number + b:number +] +recipe main [ + <span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">35</span> + <span class="Constant">4</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo + reply-unless <span class="Constant">4</span>:number + <span class="Constant">5</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">36</span> + <span class="Constant">8</span>:number<span class="Special"> <- </span>hash <span class="Constant">5</span>:foo + reply-unless <span class="Constant">8</span>:number + <span class="Constant">9</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">4</span>:number<span class="Delimiter">,</span> <span class="Constant">8</span>:number +] +<span class="Comment"># hash on containers includes all elements</span> +<span class="traceContains">+mem: storing 0 in location 9</span> + +<span class="Delimiter">:(scenario hash_can_ignore_container_elements)</span> +container foo [ + x:number + y:character/ignore-for-hash +] +recipe main [ + <span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a + <span class="Constant">3</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo + reply-unless <span class="Constant">3</span>:number + <span class="Constant">4</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">98</span>/a + <span class="Constant">6</span>:number<span class="Special"> <- </span>hash <span class="Constant">4</span>:foo + reply-unless <span class="Constant">6</span>:number + <span class="Constant">7</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">3</span>:number<span class="Delimiter">,</span> <span class="Constant">6</span>:number +] +<span class="Comment"># hashes match even though y is different</span> +<span class="traceContains">+mem: storing 1 in location 7</span> + +<span class="Comment">//: These properties aren't necessary for hash, they just test that the</span> +<span class="Comment">//: current implementation works like we think it does.</span> + +<span class="Delimiter">:(scenario hash_of_zero_address)</span> +recipe main [ + <span class="Constant">1</span>:address:number<span class="Special"> <- </span>copy <span class="Constant">0</span> + <span class="Constant">2</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:address:number +] +<span class="traceContains">+mem: storing 0 in location 2</span> + +<span class="Comment">//: This is probably too aggressive, but we need some way to avoid depending</span> +<span class="Comment">//: on the precise bit pattern of a floating-point number.</span> +<span class="Delimiter">:(scenario hash_of_numbers_ignores_fractional_part)</span> +recipe main [ + <span class="Constant">1</span>:number<span class="Special"> <- </span>hash <span class="Constant">1.5</span> + <span class="Constant">2</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span> + <span class="Constant">3</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:number<span class="Delimiter">,</span> <span class="Constant">2</span>:number +] +<span class="traceContains">+mem: storing 1 in location 3</span> + +<span class="Delimiter">:(scenario hash_of_array_same_as_string)</span> +recipe main [ + <span class="Constant">10</span>:number<span class="Special"> <- </span>copy <span class="Constant">3</span> + <span class="Constant">11</span>:number<span class="Special"> <- </span>copy <span class="Constant">97</span> + <span class="Constant">12</span>:number<span class="Special"> <- </span>copy <span class="Constant">98</span> + <span class="Constant">13</span>:number<span class="Special"> <- </span>copy <span class="Constant">99</span> + <span class="Constant">2</span>:number<span class="Special"> <- </span>hash <span class="Constant">10</span>:array:number/unsafe + reply-unless <span class="Constant">2</span>:number + <span class="Constant">3</span>:address:shared:array:character<span class="Special"> <- </span>new [abc] + <span class="Constant">4</span>:number<span class="Special"> <- </span>hash <span class="Constant">3</span>:address:shared:array:character + reply-unless <span class="Constant">4</span>:number + <span class="Constant">5</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">2</span>:number<span class="Delimiter">,</span> <span class="Constant">4</span>:number +] +<span class="traceContains">+mem: storing 1 in location 5</span> + +<span class="Delimiter">:(scenario hash_ignores_address_value)</span> +recipe main [ + <span class="Constant">1</span>:address:shared:number<span class="Special"> <- </span>new number:type + *<span class="Constant">1</span>:address:shared:number<span class="Special"> <- </span>copy <span class="Constant">34</span> + <span class="Constant">2</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:address:shared:number + <span class="Constant">3</span>:address:shared:number<span class="Special"> <- </span>new number:type + *<span class="Constant">3</span>:address:shared:number<span class="Special"> <- </span>copy <span class="Constant">34</span> + <span class="Constant">4</span>:number<span class="Special"> <- </span>hash <span class="Constant">3</span>:address:shared:number + <span class="Constant">5</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">2</span>:number<span class="Delimiter">,</span> <span class="Constant">4</span>:number +] +<span class="Comment"># different addresses hash to the same result as long as the values the point to do so</span> +<span class="traceContains">+mem: storing 1 in location 5</span> + +<span class="Delimiter">:(scenario hash_ignores_address_refcount)</span> +recipe main [ + <span class="Constant">1</span>:address:shared:number<span class="Special"> <- </span>new number:type + *<span class="Constant">1</span>:address:shared:number<span class="Special"> <- </span>copy <span class="Constant">34</span> + <span class="Constant">2</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:address:shared:number + reply-unless <span class="Constant">2</span>:number + <span class="Comment"># increment refcount</span> + <span class="Constant">3</span>:address:shared:number<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:shared:number + <span class="Constant">4</span>:number<span class="Special"> <- </span>hash <span class="Constant">3</span>:address:shared:number + reply-unless <span class="Constant">4</span>:number + <span class="Constant">5</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">2</span>:number<span class="Delimiter">,</span> <span class="Constant">4</span>:number +] +<span class="Comment"># hash doesn't change when refcount changes</span> +<span class="traceContains">+mem: storing 1 in location 5</span> + +<span class="Delimiter">:(scenario hash_container_depends_only_on_elements)</span> +container foo [ + x:number + y:character +] +container bar [ + x:number + y:character +] +recipe main [ + <span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a + <span class="Constant">3</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo + reply-unless <span class="Constant">3</span>:number + <span class="Constant">4</span>:bar<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a + <span class="Constant">6</span>:number<span class="Special"> <- </span>hash <span class="Constant">4</span>:bar + reply-unless <span class="Constant">6</span>:number + <span class="Constant">7</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">3</span>:number<span class="Delimiter">,</span> <span class="Constant">6</span>:number +] +<span class="Comment"># containers with identical elements return identical hashes</span> +<span class="traceContains">+mem: storing 1 in location 7</span> + +<span class="Delimiter">:(scenario hash_container_depends_only_on_elements_2)</span> +container foo [ + x:number + y:character + z:address:shared:number +] +recipe main [ + <span class="Constant">1</span>:address:shared:number<span class="Special"> <- </span>new number:type + *<span class="Constant">1</span>:address:shared:number<span class="Special"> <- </span>copy <span class="Constant">34</span> + <span class="Constant">2</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">1</span>:address:shared:number + <span class="Constant">5</span>:number<span class="Special"> <- </span>hash <span class="Constant">2</span>:foo + reply-unless <span class="Constant">5</span>:number + <span class="Constant">6</span>:address:shared:number<span class="Special"> <- </span>new number:type + *<span class="Constant">6</span>:address:shared:number<span class="Special"> <- </span>copy <span class="Constant">34</span> + <span class="Constant">7</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">6</span>:address:shared:number + <span class="Constant">10</span>:number<span class="Special"> <- </span>hash <span class="Constant">7</span>:foo + reply-unless <span class="Constant">10</span>:number + <span class="Constant">11</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">5</span>:number<span class="Delimiter">,</span> <span class="Constant">10</span>:number +] +<span class="Comment"># containers with identical 'leaf' elements return identical hashes</span> +<span class="traceContains">+mem: storing 1 in location 11</span> + +<span class="Delimiter">:(scenario hash_container_depends_only_on_elements_3)</span> +container foo [ + x:number + y:character + z:bar +] +container bar [ + x:number + y:number +] +recipe main [ + <span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">47</span><span class="Delimiter">,</span> <span class="Constant">48</span> + <span class="Constant">6</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo + reply-unless <span class="Constant">6</span>:number + <span class="Constant">7</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">47</span><span class="Delimiter">,</span> <span class="Constant">48</span> + <span class="Constant">12</span>:number<span class="Special"> <- </span>hash <span class="Constant">7</span>:foo + reply-unless <span class="Constant">12</span>:number + <span class="Constant">13</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">6</span>:number<span class="Delimiter">,</span> <span class="Constant">12</span>:number +] +<span class="Comment"># containers with identical 'leaf' elements return identical hashes</span> +<span class="traceContains">+mem: storing 1 in location 13</span> + +<span class="Delimiter">:(scenario hash_exclusive_container_ignores_tag)</span> +exclusive-container foo [ + x:bar + y:number +] +container bar [ + a:number + b:number +] +recipe main [ + <span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">35</span> + <span class="Constant">4</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo + reply-unless <span class="Constant">4</span>:number + <span class="Constant">5</span>:bar<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">35</span> + <span class="Constant">7</span>:number<span class="Special"> <- </span>hash <span class="Constant">5</span>:bar + reply-unless <span class="Constant">7</span>:number + <span class="Constant">8</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">4</span>:number<span class="Delimiter">,</span> <span class="Constant">7</span>:number +] +<span class="Comment"># hash on containers includes all elements</span> +<span class="traceContains">+mem: storing 1 in location 8</span> + +<span class="Comment">//: An older version that supported only strings.</span> +<span class="Comment">//: Hash functions are subtle and easy to get wrong, so we keep the old</span> +<span class="Comment">//: version around and check that the new one is consistent with it.</span> + +<span class="Delimiter">:(scenario hash_matches_old_version)</span> +recipe main [ + <span class="Constant">1</span>:address:shared:array:character<span class="Special"> <- </span>new [abc] + <span class="Constant">2</span>:number<span class="Special"> <- </span>hash <span class="Constant">1</span>:address:shared:array:character + <span class="Constant">3</span>:number<span class="Special"> <- </span>hash_old <span class="Constant">1</span>:address:shared:array:character + <span class="Constant">4</span>:number<span class="Special"> <- </span>equal <span class="Constant">2</span>:number<span class="Delimiter">,</span> <span class="Constant">3</span>:number +] +<span class="traceContains">+mem: storing 1 in location 4</span> + +<span class="Delimiter">:(before "End Primitive Recipe Declarations")</span> +HASH_OLD<span class="Delimiter">,</span> +<span class="Delimiter">:(before "End Primitive Recipe Numbers")</span> +put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">"hash_old"</span><span class="Delimiter">,</span> HASH_OLD<span class="Delimiter">);</span> +<span class="Delimiter">:(before "End Primitive Recipe Checks")</span> +case HASH_OLD: <span class="Delimiter">{</span> + if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span> + raise_error << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"'hash_old' takes exactly one ingredient rather than '"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> + <span class="Delimiter">}</span> + if <span class="Delimiter">(</span>!is_mu_string<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)))</span> <span class="Delimiter">{</span> + raise_error << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"'hash_old' currently only supports strings (address:shared:array:character), but got "</span> << inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>original_string << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> + <span class="Delimiter">}</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> +<span class="Delimiter">}</span> +<span class="Delimiter">:(before "End Primitive Recipe Implementations")</span> +case HASH_OLD: <span class="Delimiter">{</span> + string input = read_mu_string<span class="Delimiter">(</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">));</span> + size_t h = <span class="Constant">0</span> <span class="Delimiter">;</span> + + for <span class="Delimiter">(</span>long long int i = <span class="Constant">0</span><span class="Delimiter">;</span> i < SIZE<span class="Delimiter">(</span>input<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span> + h += static_cast<size_t><span class="Delimiter">(</span>input<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">));</span> + h += <span class="Delimiter">(</span>h<<<span class="Constant">10</span><span class="Delimiter">);</span> + h ^= <span class="Delimiter">(</span>h>><span class="Constant">6</span><span class="Delimiter">);</span> + + h += <span class="Delimiter">(</span>h<<<span class="Constant">3</span><span class="Delimiter">);</span> + h ^= <span class="Delimiter">(</span>h>><span class="Constant">11</span><span class="Delimiter">);</span> + h += <span class="Delimiter">(</span>h<<<span class="Constant">15</span><span class="Delimiter">);</span> + <span class="Delimiter">}</span> + + products<span class="Delimiter">.</span>resize<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span> + products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>push_back<span class="Delimiter">(</span>h<span class="Delimiter">);</span> + <span class="Identifier">break</span><span class="Delimiter">;</span> +<span class="Delimiter">}</span> +</pre> +</body> +</html> +<!-- vim: set foldmethod=manual : --> |