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| author | Pedro F. Giffuni <pfg@FreeBSD.org> | 2015-05-12 03:27:06 +0000 |
|---|---|---|
| committer | Pedro F. Giffuni <pfg@FreeBSD.org> | 2015-05-12 03:27:06 +0000 |
| commit | f4e75c6395310fa4b119d3eaa9a4a9f8913df200 (patch) | |
| tree | 2b015c205d81fa2431f0c36d7d9e903088a56d1c /doc/ficl_debug.html | |
| parent | be98e1ae3decabdd852fbe6496166aaa9acfbf9e (diff) | |
Notes
Diffstat (limited to 'doc/ficl_debug.html')
| -rw-r--r-- | doc/ficl_debug.html | 111 |
1 files changed, 0 insertions, 111 deletions
diff --git a/doc/ficl_debug.html b/doc/ficl_debug.html deleted file mode 100644 index 647b7b27a8d0..000000000000 --- a/doc/ficl_debug.html +++ /dev/null @@ -1,111 +0,0 @@ -<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> -<html> -<head> - <meta name="Author" content="john sadler"> - <title>Ficl Debugger</title> -</head> -<body> -<link REL="SHORTCUT ICON" href="ficl.ico"> -<h1><b>Ficl Debugger</b></h1> - -<script language="javascript" src="ficlheader.js"></script> - -<table COLS=1 WIDTH="650" > -<tr> -<td> -<p>Ficl release 2.05 includes a simple step debugger for colon definitions -and does> words. If you use it and can suggest improvements (or better -yet if you write some), please let me know.</p> -<h2>Using the debugger</h2> -To debug a word, set up the stack with any parameters the word requires, -then type: - -<b><pre>debug <your word here></pre></b> - -<p>If the word is unnamed, or all you have is an xt, you can instead use:</p> -<b><code>debug-xt ( xt -- )</code></b> -<p>The debugger invokes <tt>see</tt> on the word, printing a crude source -listing, then stops at the first instruction of the definition. There are -four (case insensitive) commands you can use from here onwards:</p> - -<dl> -<dt>I (step in)</dt> -<dd>If the next instruction is a colon defintion or does> word, steps into -that word's code. If the word is a primitive, simply executes the word.</dd> - -<dt>O (step over)</dt> -<dd>Executes the next instruction in its entirety</dd> - -<dt>G (go)</dt> -<dd>Run the word to completion and exit the debugger</dd> - -<dt>L (list)</dt> -<dd>Lists the source code of the word presently being stepped</dd> - -<dt>Q (quit)</dt> -<dd>Abort the word and exit the debugger, clearing the stack</dd> - -<dt>X (eXecute)</dt> -<dd>Interpret the remainder of the line as ficl words for their side effects. -Any errors will abort the debug session and reset the VM. Usage example: -<pre> -x drop 3 \ fix argument on stack -</pre> -</dd> - -<dt>Anything else</dt> -<dd>Prints a list of available debugger commands</dd> -</dl> - -<h2>The on-step event</h2> -<p>If there is a defined word named <code>on-step</code> when the debugger starts, that -word will be executed before every step. As a guideline, this word should -have no side effects. Its intended use is to display the stacks and any other -VM state you're interested in, but you -may have some better ideas. If so, please let me know. The default on-step is:<p> -<b><code>: on-step ." S: " .s cr ;</code></b> - -<h3>Other useful words for debugging and on-step</h3> -<dl> -<dt><code>r.s ( -- )</code></dt> -<dd>Prints a represention of the state of the return stack non-destructively. You have to have -a good understanding of the return stack side-effects of control words to make sense of it, -but it does give an accurate representation of what's there. Example: <code>DO .. LOOP</code>s stack -three parameters on the return stack: the loop count and limit, and the <code>LEAVE</code> target -address.</dd> -<dt><code>.s ( -- )</code></dt> -<dd>Prints the parameter stack non-destructively</dd> -<dt><code>f.s ( -- )</code></dt> -<dd>Prints the float stack non-destructively (only available if FICL_WANT_FLOAT is enabled)</dd> -</dl> -<h2>Debugger internals</h2> -<p> -The debugger words are mostly located in source file <tt>tools.c</tt>. There are -supporting words (<code>debug</code> and <code>on-step</code>) in softcore.fr as well. -There are two main words that make the debugger go: debug-xt and step-break. -Debug-xt takes the xt of a word to debug (as returned by <tt>'</tt>, for example) -checks to see if it is debuggable (not a primitive), sets a breakpoint at its -first instruction, and runs <code>see</code> on it. To set a breakpoint, -<code>debug-xt</code> -replaces the instruction at the breakpoint with the xt of <code>step-break</code>, and -stores the original instruction and its address in a static breakpoint -record. To clear the breakpoint, <code>step-break</code> simply replaces the original -instruction and adjusts the target virtual machine's instruction pointer -to run it. -</p> -<p><code>Step-break</code> is responsible for processing debugger commands and setting -breakpoints at subsequent instructions.</p> -<h3>To Do</h3> -<bl> -<li>The debugger needs to exit automatically when it encounters the end of the word -it was asked to debug. Perhaps this could be a special kind of breakpoint? -</li> -<li>Add user-set breakpoints</li> -<li>Add "step out" command</li> -</bl> -</td> -</tr> -</table> - -</body> -</html> |