diff options
Diffstat (limited to 'src/bf')
| -rw-r--r-- | src/bf/bf.rs.html | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/src/bf/bf.rs.html b/src/bf/bf.rs.html new file mode 100644 index 0000000..25b814e --- /dev/null +++ b/src/bf/bf.rs.html @@ -0,0 +1,585 @@ +<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `examples/bf.rs`."><title>bf.rs - source</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-46f98efaafac5295.ttf.woff2,FiraSans-Regular-018c141bf0843ffd.woff2,FiraSans-Medium-8f9a781e4970d388.woff2,SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2,SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-b0742ba02757f159.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="bf" data-themes="" data-resource-suffix="" data-rustdoc-version="1.83.0 (90b35a623 2024-11-26)" data-channel="1.83.0" data-search-js="search-f0d225181b97f9a4.js" data-settings-js="settings-805db61a62df4bd2.js" ><script src="../../static.files/storage-1d39b6787ed640ff.js"></script><script defer src="../../static.files/src-script-e66d777a5a92e9b2.js"></script><script defer src="../../src-files.js"></script><script defer src="../../static.files/main-f070b9041d14864c.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-0111fcff984fae8f.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc src"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="src-sidebar-title"><h2>Files</h2></div></nav><div class="sidebar-resizer"></div><main><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><h1><div class="sub-heading">bf/</div>bf.rs</h1><rustdoc-toolbar></rustdoc-toolbar></div><div class="example-wrap"><div data-nosnippet><pre class="src-line-numbers"> +<a href="#1" id="1">1</a> +<a href="#2" id="2">2</a> +<a href="#3" id="3">3</a> +<a href="#4" id="4">4</a> +<a href="#5" id="5">5</a> +<a href="#6" id="6">6</a> +<a href="#7" id="7">7</a> +<a href="#8" id="8">8</a> +<a href="#9" id="9">9</a> +<a href="#10" id="10">10</a> +<a href="#11" id="11">11</a> +<a href="#12" id="12">12</a> +<a href="#13" id="13">13</a> +<a href="#14" id="14">14</a> +<a href="#15" id="15">15</a> +<a href="#16" id="16">16</a> +<a href="#17" id="17">17</a> +<a href="#18" id="18">18</a> +<a href="#19" id="19">19</a> +<a href="#20" id="20">20</a> +<a href="#21" id="21">21</a> +<a href="#22" id="22">22</a> +<a href="#23" id="23">23</a> +<a href="#24" id="24">24</a> +<a href="#25" id="25">25</a> +<a href="#26" id="26">26</a> +<a href="#27" id="27">27</a> +<a href="#28" id="28">28</a> +<a href="#29" id="29">29</a> +<a href="#30" id="30">30</a> +<a href="#31" id="31">31</a> +<a href="#32" id="32">32</a> +<a href="#33" id="33">33</a> +<a href="#34" id="34">34</a> +<a href="#35" id="35">35</a> +<a href="#36" id="36">36</a> +<a href="#37" id="37">37</a> +<a href="#38" id="38">38</a> +<a href="#39" id="39">39</a> +<a href="#40" id="40">40</a> +<a href="#41" id="41">41</a> +<a href="#42" id="42">42</a> +<a href="#43" id="43">43</a> +<a href="#44" id="44">44</a> +<a href="#45" id="45">45</a> +<a href="#46" id="46">46</a> +<a href="#47" id="47">47</a> +<a href="#48" id="48">48</a> +<a href="#49" id="49">49</a> +<a href="#50" id="50">50</a> +<a href="#51" id="51">51</a> +<a href="#52" id="52">52</a> +<a href="#53" id="53">53</a> +<a href="#54" id="54">54</a> +<a href="#55" id="55">55</a> +<a href="#56" id="56">56</a> +<a href="#57" id="57">57</a> +<a href="#58" id="58">58</a> +<a href="#59" id="59">59</a> +<a href="#60" id="60">60</a> +<a href="#61" id="61">61</a> +<a href="#62" id="62">62</a> +<a href="#63" id="63">63</a> +<a href="#64" id="64">64</a> +<a href="#65" id="65">65</a> +<a href="#66" id="66">66</a> +<a href="#67" id="67">67</a> +<a href="#68" id="68">68</a> +<a href="#69" id="69">69</a> +<a href="#70" id="70">70</a> +<a href="#71" id="71">71</a> +<a href="#72" id="72">72</a> +<a href="#73" id="73">73</a> +<a href="#74" id="74">74</a> +<a href="#75" id="75">75</a> +<a href="#76" id="76">76</a> +<a href="#77" id="77">77</a> +<a href="#78" id="78">78</a> +<a href="#79" id="79">79</a> +<a href="#80" id="80">80</a> +<a href="#81" id="81">81</a> +<a href="#82" id="82">82</a> +<a href="#83" id="83">83</a> +<a href="#84" id="84">84</a> +<a href="#85" id="85">85</a> +<a href="#86" id="86">86</a> +<a href="#87" id="87">87</a> +<a href="#88" id="88">88</a> +<a href="#89" id="89">89</a> +<a href="#90" id="90">90</a> +<a href="#91" id="91">91</a> +<a href="#92" id="92">92</a> +<a href="#93" id="93">93</a> +<a href="#94" id="94">94</a> +<a href="#95" id="95">95</a> +<a href="#96" id="96">96</a> +<a href="#97" id="97">97</a> +<a href="#98" id="98">98</a> +<a href="#99" id="99">99</a> +<a href="#100" id="100">100</a> +<a href="#101" id="101">101</a> +<a href="#102" id="102">102</a> +<a href="#103" id="103">103</a> +<a href="#104" id="104">104</a> +<a href="#105" id="105">105</a> +<a href="#106" id="106">106</a> +<a href="#107" id="107">107</a> +<a href="#108" id="108">108</a> +<a href="#109" id="109">109</a> +<a href="#110" id="110">110</a> +<a href="#111" id="111">111</a> +<a href="#112" id="112">112</a> +<a href="#113" id="113">113</a> +<a href="#114" id="114">114</a> +<a href="#115" id="115">115</a> +<a href="#116" id="116">116</a> +<a href="#117" id="117">117</a> +<a href="#118" id="118">118</a> +<a href="#119" id="119">119</a> +<a href="#120" id="120">120</a> +<a href="#121" id="121">121</a> +<a href="#122" id="122">122</a> +<a href="#123" id="123">123</a> +<a href="#124" id="124">124</a> +<a href="#125" id="125">125</a> +<a href="#126" id="126">126</a> +<a href="#127" id="127">127</a> +<a href="#128" id="128">128</a> +<a href="#129" id="129">129</a> +<a href="#130" id="130">130</a> +<a href="#131" id="131">131</a> +<a href="#132" id="132">132</a> +<a href="#133" id="133">133</a> +<a href="#134" id="134">134</a> +<a href="#135" id="135">135</a> +<a href="#136" id="136">136</a> +<a href="#137" id="137">137</a> +<a href="#138" id="138">138</a> +<a href="#139" id="139">139</a> +<a href="#140" id="140">140</a> +<a href="#141" id="141">141</a> +<a href="#142" id="142">142</a> +<a href="#143" id="143">143</a> +<a href="#144" id="144">144</a> +<a href="#145" id="145">145</a> +<a href="#146" id="146">146</a> +<a href="#147" id="147">147</a> +<a href="#148" id="148">148</a> +<a href="#149" id="149">149</a> +<a href="#150" id="150">150</a> +<a href="#151" id="151">151</a> +<a href="#152" id="152">152</a> +<a href="#153" id="153">153</a> +<a href="#154" id="154">154</a> +<a href="#155" id="155">155</a> +<a href="#156" id="156">156</a> +<a href="#157" id="157">157</a> +<a href="#158" id="158">158</a> +<a href="#159" id="159">159</a> +<a href="#160" id="160">160</a> +<a href="#161" id="161">161</a> +<a href="#162" id="162">162</a> +<a href="#163" id="163">163</a> +<a href="#164" id="164">164</a> +<a href="#165" id="165">165</a> +<a href="#166" id="166">166</a> +<a href="#167" id="167">167</a> +<a href="#168" id="168">168</a> +<a href="#169" id="169">169</a> +<a href="#170" id="170">170</a> +<a href="#171" id="171">171</a> +<a href="#172" id="172">172</a> +<a href="#173" id="173">173</a> +<a href="#174" id="174">174</a> +<a href="#175" id="175">175</a> +<a href="#176" id="176">176</a> +<a href="#177" id="177">177</a> +<a href="#178" id="178">178</a> +<a href="#179" id="179">179</a> +<a href="#180" id="180">180</a> +<a href="#181" id="181">181</a> +<a href="#182" id="182">182</a> +<a href="#183" id="183">183</a> +<a href="#184" id="184">184</a> +<a href="#185" id="185">185</a> +<a href="#186" id="186">186</a> +<a href="#187" id="187">187</a> +<a href="#188" id="188">188</a> +<a href="#189" id="189">189</a> +<a href="#190" id="190">190</a> +<a href="#191" id="191">191</a> +<a href="#192" id="192">192</a> +<a href="#193" id="193">193</a> +<a href="#194" id="194">194</a> +<a href="#195" id="195">195</a> +<a href="#196" id="196">196</a> +<a href="#197" id="197">197</a> +<a href="#198" id="198">198</a> +<a href="#199" id="199">199</a> +<a href="#200" id="200">200</a> +<a href="#201" id="201">201</a> +<a href="#202" id="202">202</a> +<a href="#203" id="203">203</a> +<a href="#204" id="204">204</a> +<a href="#205" id="205">205</a> +<a href="#206" id="206">206</a> +<a href="#207" id="207">207</a> +<a href="#208" id="208">208</a> +<a href="#209" id="209">209</a> +<a href="#210" id="210">210</a> +<a href="#211" id="211">211</a> +<a href="#212" id="212">212</a> +<a href="#213" id="213">213</a> +<a href="#214" id="214">214</a> +<a href="#215" id="215">215</a> +<a href="#216" id="216">216</a> +<a href="#217" id="217">217</a> +<a href="#218" id="218">218</a> +<a href="#219" id="219">219</a> +<a href="#220" id="220">220</a> +<a href="#221" id="221">221</a> +<a href="#222" id="222">222</a> +<a href="#223" id="223">223</a> +<a href="#224" id="224">224</a> +<a href="#225" id="225">225</a> +<a href="#226" id="226">226</a> +<a href="#227" id="227">227</a> +<a href="#228" id="228">228</a> +<a href="#229" id="229">229</a> +<a href="#230" id="230">230</a> +<a href="#231" id="231">231</a> +<a href="#232" id="232">232</a> +<a href="#233" id="233">233</a> +<a href="#234" id="234">234</a> +<a href="#235" id="235">235</a> +<a href="#236" id="236">236</a> +<a href="#237" id="237">237</a> +<a href="#238" id="238">238</a> +<a href="#239" id="239">239</a> +<a href="#240" id="240">240</a> +<a href="#241" id="241">241</a> +<a href="#242" id="242">242</a> +<a href="#243" id="243">243</a> +<a href="#244" id="244">244</a> +<a href="#245" id="245">245</a> +<a href="#246" id="246">246</a> +<a href="#247" id="247">247</a> +<a href="#248" id="248">248</a> +<a href="#249" id="249">249</a> +<a href="#250" id="250">250</a> +<a href="#251" id="251">251</a> +<a href="#252" id="252">252</a> +<a href="#253" id="253">253</a> +<a href="#254" id="254">254</a> +<a href="#255" id="255">255</a> +<a href="#256" id="256">256</a> +<a href="#257" id="257">257</a> +<a href="#258" id="258">258</a> +<a href="#259" id="259">259</a> +<a href="#260" id="260">260</a> +<a href="#261" id="261">261</a> +<a href="#262" id="262">262</a> +<a href="#263" id="263">263</a> +<a href="#264" id="264">264</a> +<a href="#265" id="265">265</a> +<a href="#266" id="266">266</a> +<a href="#267" id="267">267</a> +<a href="#268" id="268">268</a> +<a href="#269" id="269">269</a> +<a href="#270" id="270">270</a> +<a href="#271" id="271">271</a> +<a href="#272" id="272">272</a> +<a href="#273" id="273">273</a> +<a href="#274" id="274">274</a> +<a href="#275" id="275">275</a> +<a href="#276" id="276">276</a> +<a href="#277" id="277">277</a> +<a href="#278" id="278">278</a> +<a href="#279" id="279">279</a> +<a href="#280" id="280">280</a> +<a href="#281" id="281">281</a> +<a href="#282" id="282">282</a> +<a href="#283" id="283">283</a> +<a href="#284" id="284">284</a> +<a href="#285" id="285">285</a> +<a href="#286" id="286">286</a> +<a href="#287" id="287">287</a> +<a href="#288" id="288">288</a> +<a href="#289" id="289">289</a> +<a href="#290" id="290">290</a> +<a href="#291" id="291">291</a> +<a href="#292" id="292">292</a></pre></div><pre class="rust"><code><span class="doccomment">//! Brainfuck VM. +//! +//! This example implements a simple +//! [brainfuck](https://en.wikipedia.org/wiki/Brainfuck) interpreter +//! [`BrainfuckInterp`] and a jit compiler [`BrainfuckJit`]. +//! +//! Brainfuck is an esoteric programming languge existing of 8 commands. +//! - `>` increment data pointer. +//! - `<` decrement data pointer. +//! - `+` increment data at current data pointer. +//! - `-` decrement data at current data pointer. +//! - `.` output data at current data pointer. +//! - `,` read input and store at current data pointer. +//! - `[` jump behind matching ']' if data at data pointer is zero. +//! - `]` jump behind matching '[' if data at data pointer is non-zero. + +</span><span class="kw">use </span>std::collections::HashMap; +<span class="kw">use </span>std::io::Write; + +<span class="kw">use </span>juicebox_asm::insn::<span class="kw-2">*</span>; +<span class="kw">use </span>juicebox_asm::Runtime; +<span class="kw">use </span>juicebox_asm::{Asm, Imm64, Imm8, Label, MemOp, MemOp8, Reg64, Reg8}; + +<span class="kw">struct </span>BrainfuckInterp { + pc: usize, + imem: Vec<char>, + dptr: usize, + dmem: [u8; <span class="number">256</span>], + branches: HashMap<usize, usize>, +} + +<span class="kw">impl </span>BrainfuckInterp { + <span class="kw">fn </span>new(prog: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><<span class="self">Self</span>, String> { + <span class="comment">// Do a first pass over the bf program to filter whitespace and detect invalid tokens. + // Additionally validate all conditional branches, and compute their branch target. + </span><span class="kw">let </span>(imem, branches) = { + <span class="comment">// Instruction memory holding the final bf program. + </span><span class="kw">let </span><span class="kw-2">mut </span>imem = Vec::new(); + <span class="comment">// Helper to track index of open brackets. + </span><span class="kw">let </span><span class="kw-2">mut </span>lhs_brackets = Vec::new(); + <span class="comment">// Mapping from branch instruction to branch target. + </span><span class="kw">let </span><span class="kw-2">mut </span>branches = HashMap::new(); + + <span class="kw">for </span>(idx, token) <span class="kw">in </span>prog.chars().filter(|c| !c.is_whitespace()).enumerate() { + <span class="kw">match </span>token { + <span class="string">'<' </span>| <span class="string">'>' </span>| <span class="string">'+' </span>| <span class="string">'-' </span>| <span class="string">'.' </span>| <span class="string">',' </span>=> { <span class="comment">/* ignore valid bf tokens */ </span>} + <span class="string">'[' </span>=> lhs_brackets.push(idx), + <span class="string">']' </span>=> { + <span class="kw">if let </span><span class="prelude-val">Some</span>(lhs) = lhs_brackets.pop() { + branches.insert(lhs, idx); + branches.insert(idx, lhs); + } <span class="kw">else </span>{ + <span class="kw">return </span><span class="prelude-val">Err</span>(<span class="macro">format!</span>(<span class="string">"encountered un-balanced brackets, found ']' at index {idx} without matching '['"</span>)); + } + } + <span class="kw">_ </span>=> <span class="kw">return </span><span class="prelude-val">Err</span>(<span class="macro">format!</span>(<span class="string">"invalid bf token '{token}'"</span>)), + } + imem.push(token) + } + + <span class="kw">if </span>!lhs_brackets.is_empty() { + <span class="kw">return </span><span class="prelude-val">Err</span>(String::from( + <span class="string">"encountered un-balanced brackets, left-over '[' after parsing bf program"</span>, + )); + } + + (imem, branches) + }; + + <span class="prelude-val">Ok</span>(BrainfuckInterp { + pc: <span class="number">0</span>, + imem, + dptr: <span class="number">0</span>, + dmem: [<span class="number">0</span>; <span class="number">256</span>], + branches, + }) + } +} + +<span class="kw">fn </span>run_interp(prog: <span class="kw-2">&</span>str) { + <span class="kw">let </span><span class="kw-2">mut </span>vm = BrainfuckInterp::new(prog).unwrap(); + + <span class="kw">loop </span>{ + <span class="kw">let </span>insn = <span class="kw">match </span>vm.imem.get(vm.pc) { + <span class="prelude-val">Some</span>(insn) => insn, + <span class="prelude-val">None </span>=> <span class="kw">break</span>, <span class="comment">// End of bf program. + </span>}; + + <span class="kw">let </span>putchar = |val: u8| { + std::io::stdout() + .write(<span class="kw-2">&</span>[val]) + .expect(<span class="string">"Failed to write to stdout!"</span>); + }; + + <span class="kw">match </span>insn { + <span class="string">'>' </span>=> { + vm.dptr += <span class="number">1</span>; + <span class="macro">assert!</span>(vm.dptr < vm.dmem.len()); + } + <span class="string">'<' </span>=> { + <span class="macro">assert!</span>(vm.dptr > <span class="number">0</span>); + vm.dptr -= <span class="number">1</span>; + } + <span class="string">'+' </span>=> { + vm.dmem[vm.dptr] += <span class="number">1</span>; + } + <span class="string">'-' </span>=> { + vm.dmem[vm.dptr] -= <span class="number">1</span>; + } + <span class="string">'.' </span>=> { + putchar(vm.dmem[vm.dptr]); + } + <span class="string">',' </span>=> { + <span class="macro">unimplemented!</span>(<span class="string">"getchar"</span>); + } + <span class="string">'[' </span>=> { + <span class="kw">if </span>vm.dmem[vm.dptr] == <span class="number">0 </span>{ + vm.pc = <span class="kw-2">*</span>vm.branches.get(<span class="kw-2">&</span>vm.pc).unwrap(); + } + } + <span class="string">']' </span>=> { + <span class="kw">if </span>vm.dmem[vm.dptr] != <span class="number">0 </span>{ + vm.pc = <span class="kw-2">*</span>vm.branches.get(<span class="kw-2">&</span>vm.pc).unwrap(); + } + } + <span class="kw">_ </span>=> <span class="macro">unreachable!</span>(), + } + + vm.pc += <span class="number">1</span>; + } +} + +<span class="comment">// -- BRAINFUCK JIT -------------------------------------------------------------- + +</span><span class="attr">#[cfg(not(any(target_arch = <span class="string">"x86_64"</span>, target_os = <span class="string">"linux"</span>)))] +</span><span class="macro">compile_error!</span>(<span class="string">"Only supported on x86_64 with SystemV abi"</span>); + +<span class="kw">struct </span>BrainfuckJit { + imem: Vec<char>, + dmem: [u8; <span class="number">256</span>], +} + +<span class="kw">impl </span>BrainfuckJit { + <span class="kw">fn </span>new(prog: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><<span class="self">Self</span>, String> { + <span class="comment">// Do a first pass over the bf program to filter whitespace and detect invalid tokens. + </span><span class="kw">let </span>imem = prog + .chars() + .filter(|c| !c.is_whitespace()) + .map(|c| <span class="kw">match </span>c { + <span class="string">'<' </span>| <span class="string">'>' </span>| <span class="string">'+' </span>| <span class="string">'-' </span>| <span class="string">'.' </span>| <span class="string">',' </span>| <span class="string">'[' </span>| <span class="string">']' </span>=> <span class="prelude-val">Ok</span>(c), + <span class="kw">_ </span>=> <span class="prelude-val">Err</span>(<span class="macro">format!</span>(<span class="string">"invalid bf token '{c}'"</span>)), + }) + .collect::<<span class="prelude-ty">Result</span><Vec<char>, String>>()<span class="question-mark">?</span>; + + <span class="prelude-val">Ok</span>(BrainfuckJit { + imem, + dmem: [<span class="number">0</span>; <span class="number">256</span>], + }) + } +} + +<span class="kw">extern </span><span class="string">"C" </span><span class="kw">fn </span>putchar(c: u8) { + std::io::stdout() + .write(<span class="kw-2">&</span>[c]) + .expect(<span class="string">"Failed to write to stdout!"</span>); +} + +<span class="kw">fn </span>run_jit(prog: <span class="kw-2">&</span>str) { + <span class="kw">let </span><span class="kw-2">mut </span>vm = BrainfuckJit::new(prog).unwrap(); + + <span class="comment">// Use callee saved registers to hold vm state, such that we don't + // need to save any state before calling out to putchar. + </span><span class="kw">let </span>dmem_base = Reg64::rbx; + <span class="kw">let </span>dmem_idx = Reg64::r12; + + <span class="kw">let </span><span class="kw-2">mut </span>asm = Asm::new(); + <span class="comment">// Move data memory pointer (argument on jit entry) into correct + // register. + </span>asm.mov(dmem_base, Reg64::rdi); + <span class="comment">// Clear data memory index. + </span>asm.xor(dmem_idx, dmem_idx); + + <span class="comment">// A stack of label pairs, used to link up forward and backward + // jumps for a given '[]' pair. + </span><span class="kw">let </span><span class="kw-2">mut </span>label_stack = Vec::new(); + + <span class="comment">// Generate code for each instruction in the bf program. + </span><span class="kw">for </span>insn <span class="kw">in </span>vm.imem { + <span class="kw">match </span>insn { + <span class="string">'>' </span>=> { + <span class="comment">// TODO: generate runtime bounds check. + </span>asm.inc(dmem_idx); + } + <span class="string">'<' </span>=> { + <span class="comment">// TODO: generate runtime bounds check. + </span>asm.dec(dmem_idx); + } + <span class="string">'+' </span>=> { + asm.inc(MemOp8::from(MemOp::IndirectBaseIndex(dmem_base, dmem_idx))); + } + <span class="string">'-' </span>=> { + asm.dec(MemOp8::from(MemOp::IndirectBaseIndex(dmem_base, dmem_idx))); + } + <span class="string">'.' </span>=> { + <span class="comment">// Load data memory from active cell into di register, + // which is the first argument register according to + // the SystemV abi, then call into putchar. Since we + // stored all out vm state in callee saved registers + // we don't need to save any registers before the + // call. + </span>asm.mov(Reg8::dil, MemOp::IndirectBaseIndex(dmem_base, dmem_idx)); + asm.mov(Reg64::rax, Imm64::from(putchar <span class="kw">as </span>usize)); + asm.call(Reg64::rax); + } + <span class="string">',' </span>=> { + <span class="macro">unimplemented!</span>(<span class="string">"getchar"</span>); + } + <span class="string">'[' </span>=> { + <span class="comment">// Create new label pair. + </span>label_stack.push((Label::new(), Label::new())); + <span class="comment">// UNWRAP: We just pushed a new entry on the stack. + </span><span class="kw">let </span>label_pair = label_stack.last_mut().unwrap(); + + <span class="comment">// Goto label_pair.0 if data memory at active cell is 0. + // if vm.dmem[vm.dptr] == 0 goto label_pair.0 + </span>asm.cmp( + MemOp::IndirectBaseIndex(dmem_base, dmem_idx), + Imm8::from(<span class="number">0u8</span>), + ); + asm.jz(<span class="kw-2">&mut </span>label_pair.<span class="number">0</span>); + + <span class="comment">// Bind label_pair.1 after the jump instruction, which + // will be the branch target for the matching ']'. + </span>asm.bind(<span class="kw-2">&mut </span>label_pair.<span class="number">1</span>); + } + <span class="string">']' </span>=> { + <span class="kw">let </span><span class="kw-2">mut </span>label_pair = label_stack + .pop() + .expect(<span class="string">"encountered un-balanced brackets, found ']' without matching '['"</span>); + + <span class="comment">// Goto label_pair.1 if data memory at active cell is + // not 0. + // if vm.dmem[vm.dptr] != 0 goto label_pair.1 + </span>asm.cmp( + MemOp::IndirectBaseIndex(dmem_base, dmem_idx), + Imm8::from(<span class="number">0u8</span>), + ); + asm.jnz(<span class="kw-2">&mut </span>label_pair.<span class="number">1</span>); + + <span class="comment">// Bind label_pair.0 after the jump instruction, which + // is the branch target for the matching '['. + </span>asm.bind(<span class="kw-2">&mut </span>label_pair.<span class="number">0</span>); + } + <span class="kw">_ </span>=> <span class="macro">unreachable!</span>(), + } + } + + <span class="comment">// Return from bf program. + </span>asm.ret(); + + <span class="kw">if </span>!label_stack.is_empty() { + <span class="macro">panic!</span>(<span class="string">"encountered un-balanced brackets, left-over '[' after jitting bf program"</span>) + } + + <span class="comment">// Execute jitted bf program. + </span><span class="kw">let </span><span class="kw-2">mut </span>rt = Runtime::new(); + <span class="kw">let </span>bf_entry = <span class="kw">unsafe </span>{ rt.add_code::<<span class="kw">extern </span><span class="string">"C" </span><span class="kw">fn</span>(<span class="kw-2">*mut </span>u8)>(asm.into_code()) }; + bf_entry(<span class="kw-2">&mut </span>vm.dmem <span class="kw">as </span><span class="kw-2">*mut </span>u8); +} + +<span class="kw">fn </span>main() { + <span class="comment">// https://en.wikipedia.org/wiki/Brainfuck#Adding_two_values + //let inp = "++>+++++ [<+>-] ++++++++[<++++++>-]<."; + //println!("add-print-7 (wikipedia.org) - interp"); + //run_interp(inp); + //println!("add-print-7 (wikipedia.org) - jit"); + //run_jit(inp); + + // https://en.wikipedia.org/wiki/Brainfuck#Hello_World! + </span><span class="kw">let </span>inp = <span class="string">"++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++."</span>; + <span class="macro">println!</span>(<span class="string">"hello-world (wikipedia.org) - interp"</span>); + run_interp(inp); + <span class="macro">println!</span>(<span class="string">"hello-world (wikipedia.org) - jit"</span>); + run_jit(inp); + + <span class="comment">// https://programmingwiki.de/Brainfuck + </span><span class="kw">let </span>inp = <span class="string">">+++++++++[<++++++++>-]<.>+++++++[<++++>-]<+.+++++++..+++.[-]>++++++++[<++++>-] <.>+++++++++++[<++++++++>-]<-.--------.+++.------.--------.[-]>++++++++[<++++>- ]<+.[-]++++++++++."</span>; + <span class="macro">println!</span>(<span class="string">"hello-world (programmingwiki.de) - interp"</span>); + run_interp(inp); + <span class="macro">println!</span>(<span class="string">"hello-world (programmingwiki.de) - jit"</span>); + run_jit(inp); +} +</code></pre></div></section></main></body></html>
\ No newline at end of file |