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Re: 3.2 bug or something really odd.


Hi Dmitry,

> As follows from the expander defenition, if the operands[2] not
> equal to 1 the extzv parrern must be ignored.  However, as follows
> from the rtl dump, gcc ignores 'FAIL' directive and issues tricky
> code.  The extzv pattern first appears after 'combine' pass.

If I remember correctly, extract_bit_field() in expmed.c does not
check all the conditions.  Write your extzv pattern using
define_expand.  If you want ensure that operands[2] is (const_int 1),
use FAIL.

KazU Hirata


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