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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Please consider a patch in attachment as fix for PR15318: AsmPrinter crashes with assertion.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><a href="http://llvm.org/bugs/show_bug.cgi?id=15318">http://llvm.org/bugs/show_bug.cgi?id=15318</a><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>APFloat::toString tries to print floating point in decimal string. It calculates the precision and padding of the output format. At the end of the AdjustPrecision function, it truncates the significand down to its active bit count but always keeps it never drop below 32 bits.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>BitWidth of significand is larger than active bits, but it is not always larger than 32. E.g. when the 64bit value 0x41EFFFFFE0000000 is read and called toString(), the BitWidth of significand is smaller than 32. Then truncating the significand to 32 will cause an assertion failure (it always asserts width < BitWidth).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>The fix is very simple, just remove the “don’t try to drop below 32” operation. Always truncate it to the active bits. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I just find it’s no need to keep significand above 32. The AdjustPrecision function does useless thing, which causes the assertion failure. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>-Hao<o:p></o:p></span></p></div></body></html>