A partial reply to the previous question and another one

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OK , grepping the whole source tree for 'ctlz' I found the answer to my question in:

test/FrontendC/2006-01-16-BitCountIntrinsicsUnsigned.c

and that is to use gnu frontend style __builtin_clz() for this one.

This test/FrontendC directory has a plethora of other usefull examples so I guess It will be sufficient for me.
However I still think that some documentation of the frontend interface for the intrinsics is sorely missing.
Or is it that LLVM is supposed to support ALL of gnu's intrinsic extensions , and in that case just refer to
the gnu documentation of intrinsics ?

Also I will need to introduce new intrinsics specific to our processor, as an example to get me started I would
like to ask the forum (as recommended in the 'extending llvm' document) how to extend it to support the following:
(or maybe there is already some support ...)

double load (load Ri, Ri+1 from an immediate address).
double store (store Ri,Ri+1 to an immediate address).

actually double load is specially challenging as an intrinsic syntax you would have to return two values ....

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Gil Dogon wrote:
[snip]

Also I will need to introduce new intrinsics specific to our processor, as an example to get me started I would
like to ask the forum (as recommended in the 'extending llvm' document) how to extend it to support the following:
(or maybe there is already some support ...)

double load (load Ri, Ri+1 from an immediate address).
double store (store Ri,Ri+1 to an immediate address).

actually double load is specially challenging as an intrinsic syntax you would have to return two values ....

If you are trying to support e.g. 64 bit data on a processor
with only 32 bit operations, LLVM does all the work for you.

Define the 32 bit insructions in your code generator and LLVM aill automagically use them for 64 bit operations.

-Rich