Andy,<br><br> Thanks for the response. I fixed this, seems to be working fairly well so far, I did have to manually iterate over phi nodes and modify each one accordingly. The value problem was a mistake on my part, the new PHI node instructions were the values. It would seem however that there should be calls, once all the branching is done, that can automate over the new cfg and determine the PHI nodes (blocks and values) needed and automatically insert them.<br>
<br>Thanks everyone.<br><br><div class="gmail_quote">On Mon, Feb 6, 2012 at 2:23 PM, Andrew Trick <span dir="ltr"><<a href="mailto:atrick@apple.com">atrick@apple.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div style="word-wrap:break-word">You're creating a new path that doesn't include L. For all values defined in L and used outside of L, you need to determine the new reaching def. That's specific to your transformation and can't be automated. Once you do that, creating the phi in F is natural.<div>
-Andy<br><div><br><div><div><div class="h5"><div>On Feb 6, 2012, at 11:51 AM, Ryan Taylor <<a href="mailto:ryta1203@gmail.com" target="_blank">ryta1203@gmail.com</a>> wrote:</div><br></div></div><blockquote type="cite">
<div><div class="h5">I guess not since Value is a superclass of Instruction.<br><br><div class="gmail_quote">On Mon, Feb 6, 2012 at 10:36 AM, Ryan Taylor <span dir="ltr"><<a href="mailto:ryta1203@gmail.com" target="_blank">ryta1203@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><br><br><div class="gmail_quote"><div>---------- Forwarded message ----------<br>From: <b class="gmail_sendername">Ryan Taylor</b> <span dir="ltr"><<a href="mailto:ryta1203@gmail.com" target="_blank">ryta1203@gmail.com</a>></span><br>
</div><div><div>Date: Mon, Feb 6, 2012 at 10:36 AM<br>
Subject: Re: [LLVMdev] Updating PHI for Instruction Domination?<br>To: Eric Christopher <<a href="mailto:echristo@apple.com" target="_blank">echristo@apple.com</a>><br><br><br>Since I'm not sure which instructions I might want to replicate, would it be possible to cast the Value from "PHINode::getIncomingValue" to "Instruction" and then copy that and cast it back?<div>
<div><br><br>
<div class="gmail_quote">On Sun, Feb 5, 2012 at 8:49 PM, Ryan Taylor <span dir="ltr"><<a href="mailto:ryta1203@gmail.com" target="_blank">ryta1203@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div><div><br><br><div class="gmail_quote">On Sun, Feb 5, 2012 at 5:15 PM, Eric Christopher <span dir="ltr"><<a href="mailto:echristo@apple.com" target="_blank">echristo@apple.com</a>></span> wrote:<br>
<blockquote style="margin:0px 0px 0px 0.8ex;padding-left:1ex;border-left-color:rgb(204,204,204);border-left-width:1px;border-left-style:solid" class="gmail_quote">
<div><br>
On Feb 2, 2012, at 5:13 PM, Ryan Taylor wrote:<br>
<br>
> So my best bet is to try and work in reg2mem mode and then go back to mem2reg?<br>
><br>
<br>
</div>I wouldn't. That sounds painful.<br>
<div><br>
> I'm curious, it seems though when you split a block that the phis get updated, right?<br>
<br>
</div>Sure. There's code in splitBasicBlock to do this. It should just take a little bit of work to get what you want done.<br>
<span><font color="#888888"><br>
-eric<br>
</font></span></blockquote></div><div> </div></div></div><div>Yes, the first DOES sound painful (I want to avoid it) and the second is not an option. I'm adding a second path in a loop.</div><div> </div><div>The old path: BB1->BB2/BB3, BB2->BB1/BB3, BB3->n/a</div>
<div> </div><div>The new path: BB1->H/BB2, BB2->F/K, H->F, K->F, F->BB1/G, G->BB3</div><div> </div><div>There are PHI nodes in BB1 that come in from BB2 for values defined in BB2. With the new possible path: BB1->H->F, BB2. Without adding new PHIs or Values, there exists a dominance instruction issue. So I want to create PHIs in F for each value in BB2 that is used in BB1. The update the PHI Values in BB1 (that used to come from BB2) to the new values in F (which are getting values from BB2/H). </div>
<div><br>The problem is that there is no way to copy the value from BB2, since there exists no Value constructor!? </div><div> </div><div>This seems like a pretty large limitation anytime anyone wants to add a branch inside a loop? Is there an easier way to get what I want that I'm missing?</div>
</blockquote></div><br>
</div></div></div></div></div><br>
</blockquote></div><br></div></div><div class="im">
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