<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The attached patch is to account for the total size of arguments passed in the caller’s stack frame when determining whether to create an emergency spill slot for register scavenging. It may be the case that the stack size estimate falls just within the allowed displacement, so that no emergency spill slot is created. In the case where we need an additional register to compute the offset when trying to access arguments passed in the caller’s stack frame, we will hit the following assert in RegScaveneger::scavengeRegister(…) if we cannot scavenge a spare register without spilling:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>assert(Scavenged[SI].FrameIndex >= 0 &&<o:p></o:p></p><p class=MsoNormal> "Cannot scavenge register without an emergency spill slot!");<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I didn’t attach a test case as this was triggered by an internal test, and coming up with these exact conditions was proving to be a little tricky.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal>Sanjin<o:p></o:p></p></div></body></html>