<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:'times new roman', 'new york', times, serif;font-size:12pt"><div style="color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; ">Hi,</div><div style="color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; "><br></div><div style="color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; ">I noticed a bunch of psuedo instructions used for creation of constants without generating loads. e.g. pxor xmm0, xmm0</div><div><font class="Apple-style-span" face="'times new roman', 'new york', times, serif" size="4"><span class="Apple-style-span" style="font-size: 12pt;">Here is an example of what i am </span></font><font class="Apple-style-span" face="'times new roman', 'new york', times, serif">referring</font><font class="Apple-style-span" face="'times new
roman', 'new york', times, serif" size="4"><span class="Apple-style-span" style="font-size: 12pt;"> to snipped from X86InstrSSE.td:</span></font></div><div style="color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; "><br></div><div style="color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; "><div>def FsFLD0SS : I<0xEF, MRMInitReg, (outs FR32:$dst), (ins), "",</div><div> [(set FR32:$dst, fp32imm0)]>,</div><div> Requires<[HasSSE1]>, TB, OpSize;</div><div><br></div><div>My question is why was there a need to define such a pseudo instruction?</div><div>Wouldn't it be cleaner to use a def: Pat<> which selects: </div><div>pxor $dst, $dst </div><div>from:</div><div>[(set FR32:$dst, fp32imm0)] ?</div><div><br></div></div><div
style="color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; ">Thanks in advance.</div><div style="position: fixed; color: black; font-family: 'times new roman', 'new york', times, serif; font-size: 12pt; "></div>
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