<html><head><base href="x-msg://23/"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Feb 12, 2010, at 3:57 AM, Arnaud Allard de Grandmaison wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; 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: 0px; "><div lang="EN-US" link="blue" vlink="#606420"><div class="Section1"><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">Hello,<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; "><o:p> </o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">It seems I stepped on a bug with the ConstantMerge IPO pass, regarding address spaces.<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; "><o:p> </o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">For example, if a module contains the following:<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; "><o:p> </o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">@a = internal constant i16 224<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">@b = internal addrspace(30) constant i16 224<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; "><o:p> </o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">Although a & b have the same initializer, i think they should not be merged. Attempting to do it anyway will trigger an assertion.<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; "><o:p> </o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; ">I guess the safe and easy way is to only merge constants in the 0 address space, as the other address spaces may need a target specific behaviour. The patch for this is attached.<o:p></o:p></span></font></div><div style="margin-top: 0cm; margin-right: 0cm; margin-bottom: 0.0001pt; margin-left: 0cm; font-size: 12pt; font-family: 'Times New Roman'; "><font size="2" face="Arial"><span style="font-size: 10pt; font-family: Arial; "><o:p> </o:p></span></font></div></div></div></span></blockquote><br></div><div>Nice catch, I took the opportunity to clean up the constmerge pass while fixing this:</div><div><a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20100208/096071.html">http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20100208/096071.html</a></div><div><br></div><div>-Chris</div><br></body></html>