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<p class="MsoNormal"><span style="font-family:Consolas">There are many instructions in the generated AArch64GenInstrInfo.inc which may raise a floating-point exception, but do not have the MayRaiseFPException flag. For example, consider FADDSrr (FADD single-precision
register-to-register):<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"> sed '/.* \/\/ Inst #[0-9]\+ = FADDSrr/!d' AArch64GenInstrInfo.inc<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"> { 1595, 3, 1, 4, 441, 0, 0x0ULL, nullptr, nullptr, OperandInfo212 }, // Inst #1595 = FADDSrr<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas">The ISA reference clearly states<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"> This instruction can generate a floating-point exception.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"> <a href="https://developer.arm.com/documentation/ddi0596/2021-06/SIMD-FP-Instructions/FADD--scalar---Floating-point-Add--scalar--?lang=en">
https://developer.arm.com/documentation/ddi0596/2021-06/SIMD-FP-Instructions/FADD--scalar---Floating-point-Add--scalar--?lang=en</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas">1. Why doesn't this instruction have the MayRaiseFPException flag?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas">2. I would like to add the MayRaiseFPException flag to AArch64 instructions which may raise floating-point exceptions. Are there any objections?<o:p></o:p></span></p>
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