2019-09-06 15:57:44 -07:00

71 lines
9.3 KiB
HTML
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!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="API documentation for the Rust `verifier` mod in crate `cranelift_codegen`."><meta name="keywords" content="rust, rustlang, rust-lang, verifier"><title>cranelift_codegen::verifier - Rust</title><link rel="stylesheet" type="text/css" href="../../normalize.css"><link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../dark.css"><link rel="stylesheet" type="text/css" href="../../light.css" id="themeStyle"><script src="../../storage.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="shortcut icon" href="../../favicon.ico"><style type="text/css">#crate-search{background-image:url("../../down-arrow.svg");}</style></head><body class="rustdoc mod"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">&#9776;</div><a href='../../cranelift_codegen/index.html'><div class='logo-container'><img src='../../rust-logo.png' alt='logo'></div></a><p class='location'>Module verifier</p><div class="sidebar-elems"><div class="block items"><ul><li><a href="#structs">Structs</a></li><li><a href="#functions">Functions</a></li><li><a href="#types">Type Definitions</a></li></ul></div><p class='location'><a href='../index.html'>cranelift_codegen</a></p><script>window.sidebarCurrent = {name: 'verifier', ty: 'mod', relpath: '../'};</script><script defer src="../sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../theme.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"></div><a id="settings-menu" href="../../settings.html"><img src="../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='out-of-band'><span id='render-detail'><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class='inner'>&#x2212;</span>]</a></span><a class='srclink' href='../../src/cranelift_codegen/verifier/mod.rs.html#1-1819' title='goto source code'>[src]</a></span><span class='in-band'>Module <a href='../index.html'>cranelift_codegen</a>::<wbr><a class="mod" href=''>verifier</a></span></h1><div class='docblock'><p>A verifier for ensuring that functions are well formed.
It verifies:</p>
<p>EBB integrity</p>
<ul>
<li>All instructions reached from the <code>ebb_insts</code> iterator must belong to
the EBB as reported by <code>inst_ebb()</code>.</li>
<li>Every EBB must end in a terminator instruction, and no other instruction
can be a terminator.</li>
<li>Every value in the <code>ebb_params</code> iterator belongs to the EBB as reported by <code>value_ebb</code>.</li>
</ul>
<p>Instruction integrity</p>
<ul>
<li>The instruction format must match the opcode.</li>
<li>All result values must be created for multi-valued instructions.</li>
<li>All referenced entities must exist. (Values, EBBs, stack slots, ...)</li>
<li>Instructions must not reference (eg. branch to) the entry block.</li>
</ul>
<p>SSA form</p>
<ul>
<li>Values must be defined by an instruction that exists and that is inserted in
an EBB, or be an argument of an existing EBB.</li>
<li>Values used by an instruction must dominate the instruction.</li>
</ul>
<p>Control flow graph and dominator tree integrity:</p>
<ul>
<li>All predecessors in the CFG must be branches to the EBB.</li>
<li>All branches to an EBB must be present in the CFG.</li>
<li>A recomputed dominator tree is identical to the existing one.</li>
</ul>
<p>Type checking</p>
<ul>
<li>Compare input and output values against the opcode's type constraints.
For polymorphic opcodes, determine the controlling type variable first.</li>
<li>Branches and jumps must pass arguments to destination EBBs that match the
expected types exactly. The number of arguments must match.</li>
<li>All EBBs in a jump table must take no arguments.</li>
<li>Function calls are type checked against their signature.</li>
<li>The entry block must take arguments that match the signature of the current
function.</li>
<li>All return instructions must have return value operands matching the current
function signature.</li>
</ul>
<p>Global values</p>
<ul>
<li>Detect cycles in global values.</li>
<li>Detect use of 'vmctx' global value when no corresponding parameter is defined.</li>
</ul>
<p>TODO:
Ad hoc checking</p>
<ul>
<li>Stack slot loads and stores must be in-bounds.</li>
<li>Immediate constraints for certain opcodes, like <code>udiv_imm v3, 0</code>.</li>
<li><code>Insertlane</code> and <code>extractlane</code> instructions have immediate lane numbers that must be in
range for their polymorphic type.</li>
<li>Swizzle and shuffle instructions take a variable number of lane arguments. The number
of arguments must match the destination type, and the lane indexes must be in range.</li>
</ul>
</div><h2 id='structs' class='section-header'><a href="#structs">Structs</a></h2>
<table><tr class='module-item'><td><a class="struct" href="struct.VerifierError.html" title='cranelift_codegen::verifier::VerifierError struct'>VerifierError</a></td><td class='docblock-short'><p>A verifier error.</p>
</td></tr><tr class='module-item'><td><a class="struct" href="struct.VerifierErrors.html" title='cranelift_codegen::verifier::VerifierErrors struct'>VerifierErrors</a></td><td class='docblock-short'><p>List of verifier errors.</p>
</td></tr></table><h2 id='functions' class='section-header'><a href="#functions">Functions</a></h2>
<table><tr class='module-item'><td><a class="fn" href="fn.verify_context.html" title='cranelift_codegen::verifier::verify_context fn'>verify_context</a></td><td class='docblock-short'><p>Verify <code>func</code> after checking the integrity of associated context data structures <code>cfg</code> and
<code>domtree</code>.</p>
</td></tr><tr class='module-item'><td><a class="fn" href="fn.verify_cssa.html" title='cranelift_codegen::verifier::verify_cssa fn'>verify_cssa</a></td><td class='docblock-short'><p>Verify conventional SSA form for <code>func</code>.</p>
</td></tr><tr class='module-item'><td><a class="fn" href="fn.verify_function.html" title='cranelift_codegen::verifier::verify_function fn'>verify_function</a></td><td class='docblock-short'><p>Verify <code>func</code>.</p>
</td></tr><tr class='module-item'><td><a class="fn" href="fn.verify_liveness.html" title='cranelift_codegen::verifier::verify_liveness fn'>verify_liveness</a></td><td class='docblock-short'><p>Verify liveness information for <code>func</code>.</p>
</td></tr><tr class='module-item'><td><a class="fn" href="fn.verify_locations.html" title='cranelift_codegen::verifier::verify_locations fn'>verify_locations</a></td><td class='docblock-short'><p>Verify value locations for <code>func</code>.</p>
</td></tr></table><h2 id='types' class='section-header'><a href="#types">Type Definitions</a></h2>
<table><tr class='module-item'><td><a class="type" href="type.VerifierResult.html" title='cranelift_codegen::verifier::VerifierResult type'>VerifierResult</a></td><td class='docblock-short'><p>Result of a verification operation.</p>
</td></tr><tr class='module-item'><td><a class="type" href="type.VerifierStepResult.html" title='cranelift_codegen::verifier::VerifierStepResult type'>VerifierStepResult</a></td><td class='docblock-short'><p>Result of a step in the verification process.</p>
</td></tr></table></section><section id="search" class="content hidden"></section><section class="footer"></section><aside id="help" class="hidden"><div><h1 class="hidden">Help</h1><div class="shortcuts"><h2>Keyboard Shortcuts</h2><dl><dt><kbd>?</kbd></dt><dd>Show this help dialog</dd><dt><kbd>S</kbd></dt><dd>Focus the search field</dd><dt><kbd></kbd></dt><dd>Move up in search results</dd><dt><kbd></kbd></dt><dd>Move down in search results</dd><dt><kbd></kbd></dt><dd>Switch tab</dd><dt><kbd>&#9166;</kbd></dt><dd>Go to active search result</dd><dt><kbd>+</kbd></dt><dd>Expand all sections</dd><dt><kbd>-</kbd></dt><dd>Collapse all sections</dd></dl></div><div class="infos"><h2>Search Tricks</h2><p>Prefix searches with a type followed by a colon (e.g., <code>fn:</code>) to restrict the search to a given type.</p><p>Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, and <code>const</code>.</p><p>Search functions by type signature (e.g., <code>vec -> usize</code> or <code>* -> vec</code>)</p><p>Search multiple things at once by splitting your query with comma (e.g., <code>str,u8</code> or <code>String,struct:Vec,test</code>)</p></div></div></aside><script>window.rootPath = "../../";window.currentCrate = "cranelift_codegen";</script><script src="../../aliases.js"></script><script src="../../main.js"></script><script defer src="../../search-index.js"></script></body></html>