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The more I think about this, the more I like it.<br><br>However there might be a better option.<br>Gcc has some notion of built-in setjmp.<br>For that matter, maybe using the gcc exception handling mechanism isn't difficult?<br><br><br> - Jay<br><br><hr id="stopSpelling">From: jay.krell@cornell.edu<br>To: m3devel@elegosoft.com<br>Subject: factoring jmpbuf size via alloca(global constant)?<br>Date: Thu, 30 Dec 2010 14:28:31 +0000<br><br>
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factoring out jmpbuf size?<br><br><br>Hey, um, how about something like this:<br><br><br>somefile.c:<br> #include <setjmp.h><br> extern const int sizeof_jmpbuf = sizeof(jmp_buf);<br> <br><br>where the frontend would allocate a local jmp_buf,<br>instead issue a call to alloca(sizeof_jmpbuf),<br>actually reading the constant out of the global.<br><br><br>Yes I know this is a deoptimization.<br>It is already slow.<br>We hope hope hope to replace it all anyway.<br><br><br>This would remove lots of target-specific code in Target.m3.<br><br><br>Related, I'm again trying removing from m3core the knowledge<br>of the size/alignment of jmpbuf. Or rather, to see if it really<br>needs it.<br><br><br> - Jay<br><br> </body>
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