[LLVMdev] MachineConstantPoolValue

Rafael EspĂ­ndola rafael.espindola at gmail.com
Wed Dec 6 13:49:31 PST 2006

In the ARM backend, functions (and other 32 bit constants) are placed
in a pool and loaded when needed.

A problem with this is that ".weak" directives must be printed in the
pool. This is not supported in the standard printer, so I think that I
have found the first use for MachineConstantPoolValue :-)

Creating the constant is easy, but I have two problems:

1) what are the methods getExistingMachineCPValue and
AddSelectionDAGCSEId supposed to do?

2) printing is hard because we are outside the AsmPrinter.

In my current hack I am printing from
ARMAsmPrinter::EmitMachineConstantPoolValue :-(

Since this problem might also be significant to x86 (see my previous
email), maybe we should just teach the pool printer to emit ".weak"

Best Regards,

P.S.: rest assured that what is attached is just a demo hack and will
not be committed :-)
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