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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>TableGen's decoder generator does not add a break in the
switch statements for decoding structure's leaf nodes, because it considers
that the leaf nodes will always exit with a return. This is however not true
for some backends (for example the ARM backend) where we have to match multiple
architectures and an 'if' statement is generated to guard the leaf node.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>When failing the architecture check, without the break
statement, the decoder will incorrectly fall through to the next branch and
match other instructions that do not correspond to the input bitpattern.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>The attached patch fixes this by making TableGen always emit
a break statement for leaf nodes.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Please review this patch.<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>Silviu<o:p></o:p></p>
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