On Sat, Apr 30, 2011 at 4:23 AM, Yoshiki Ohshima yoshiki@vpri.org wrote:
At Thu, 28 Apr 2011 12:22:33 +0200, Mariano Martinez Peck wrote:
Hi. Suppose I am doing something in #commonSend:
commonSend "Send a message, starting lookup with the receiver's class." "Assume: messageSelector and argumentCount have been set, and that the receiver and arguments have been pushed onto the stack," "Note: This method is inlined into the interpreter dispatch loop." <sharedCodeNamed: 'commonSend' inCase: 131> self internalFindNewMethod. self internalExecuteNewMethod. self fetchNextBytecode
and somewhere there I want to do something like this:
(messageSelector = '#foo') ifTrue: [ self print: 'the message foo was
called'; cr ].
messageSelector is the instVar of Interpreter and it is already in the
stack.
Of course, the part that doesn't work is (messageSelector = '#foo') I tried several things but I don't find how to do it.
Perhaps something along the line of:
(self cCode: 'stSizeOf(messageSelector) == sizeOf('foo') && (strncmp(firstIndexableField(messageSelector), 'foo', sizeOf('foo')) == 0)) ifTrue: [self print: 'the message foo was called': cr].
(Not tested this particualr one, but have done similar thing before. This assumes that messageSelector is always a Symbol, which may not be the case for you...)
Thanks Yoshiki. After I sent this mail, and with a help of a friend, I was also trying to do something similar to that. Just by coincidense, Eliot answered me in another thread, a way to solve this in Cog, and it is using the command line argument -breaksel. With such parameter you can send a seletor as an argument, put a breakpoint with gdb, and the VM will stop in a place. It is not EXACTLY the same as what I was asking, but it is useful.
If you are interested, read his answer here: http://forum.world.st/Cog-and-commonSend-are-getting-me-crazy-td3480836.html
And yes, his code is similar to yours:
CoInterpreter >> compilationBreak: selectorOop point: selectorLength <api> <cmacro: '(sel, len) do { \ if ((len) == breakSelectorLength \ && !strncmp((char *)((sel) + BaseHeaderSize), breakSelector, breakSelectorLength)) { \ suppressHeartbeatFlag = 1; \ compilationBreakpointFor(sel); \ } \ } while (0)'> | i | breakSelectorLength = selectorLength ifTrue: [i := breakSelectorLength. [i > 0] whileTrue: [(self byteAt: selectorOop + i + BaseHeaderSize - 1) = (breakSelector at: i) asInteger ifTrue: [(i := i - 1) = 0 ifTrue: [self compilationBreakpointFor: selectorOop]] ifFalse: [i := 0]]]
Once again, thanks for your help.