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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>For the first line, the AAPCS states that all registers must be shadowed (“The NCRN is set to r4” in AAPCS terminology). I cannot think of any case where the original version would cause incorrect behaviour, but I’m not certain, and the modified version more explicitly reflects the intent of the AAPCS.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>As for the second line, again I cannot think of a case in which the original version is incorrect, but it more explicitly reflects the AAPCS rule that no GPRs should be used after a non-CPRC argument has been allocated on the stack.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I have attached an updated patch which fixed the typo and alignment error.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I will mention the change to the GPR shadowing in the commit message.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Oliver<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Renato Golin [mailto:renato.golin@linaro.org] <br><b>Sent:</b> 07 February 2014 10:19<br><b>To:</b> James Molloy<br><b>Cc:</b> Oliver Stannard; LLVM Commits<br><b>Subject:</b> Re: [PATCH] AAPCS-VFP: Do not use any more VFP registers after allocating a CPRC to the stack<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal>On 7 February 2014 10:08, James Molloy <<a href="mailto:james.molloy@arm.com" target="_blank">james.molloy@arm.com</a>> wrote:<o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The first line did shadow just R3 but now shadows all registers. I suspect that actually this was a bug, which you have now fixed incidentally? Your patch description only mentions coprocessor registers so can you just confirm this is deliberate?</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The second line has changed behaviour – previously in the i32 case no registers were shadowed – now R0-R3 are shadowed. Why is this correct? (not saying it’s not, but some justification would be good).</span><o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I assumed both cases were the same "fix" that weren't mentioned in the commit message (and that's why I was unsure of the "fix").<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>If that's correct, I agree would be good to have a mention in the commit message. ;)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>cheers,<o:p></o:p></p></div><div><p class=MsoNormal>--renato<o:p></o:p></p></div></div></div></body></html>