<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Oct 14, 2008, at 4:19 PM, Villmow, Micah wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div lang="EN-US" link="blue" vlink="purple" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div class="Section1"><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" color="navy" face="Arial"><span style="font-size: 10pt; font-family: Arial; color: navy; ">After a bunch more investigate, I’ve seem to have figured out what is going on here. The MachineFunction holds a vector of MachineBasicBlocks and it is this vector that is traversed by the MachineFunction iterator when printing out instructions. The problem is occurring when a modification to the CFG moves around so that the ordering of them is different. Even if the pred/succ blocks are modified, their position in the MBBNumbering vector does not change. This causes the CFG graph and the MachineFunction vector to become out of sync causing all sorts of issues with code generation. (i.e. having my return block being generated in the middle of a loop).<o:p></o:p></span></font></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" color="navy" face="Arial"><span style="font-size: 10pt; font-family: Arial; color: navy; "><o:p> </o:p></span></font></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" color="navy" face="Arial"><span style="font-size: 10pt; font-family: Arial; color: navy; ">I figured that sorting the vector based on the block id’s would fix this issue, but the constructor required to sort correctly is marked as private.<o:p></o:p></span></font></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" color="navy" face="Arial"><span style="font-size: 10pt; font-family: Arial; color: navy; "><o:p> </o:p></span></font></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" color="navy" face="Arial"><span style="font-size: 10pt; font-family: Arial; color: navy; ">So, my basic need is this. How do I re-order the MachineBasicBlocks vector based on their Block ID numbers via the current API(2.3)?</span></font></div></div></div></span></blockquote><div><br></div></div>The branch folding pass moves around blocks, please take a look at its implementation to see how it works,<div><br></div><div>-Chris</div></body></html>