Biv initial value detection improvement

[Joern Rennecke]

In article < 20000414141933.N21035@atrey.karlin.mff.cuni.cz > you wrote:

: Hi
: It may happen, that the BIV initialization insn use constant pseudo as an parameter.
: I think this is common on risc machines and even on i386 it may happen, when
: (cont (plus (symbol_ref ...) (const_int ...))) takes place.
: For my prefetching code it is important for initial_values to unhide this fact
: (and it improves BIV combining oppurtunities as well) as well as knowing
: initial value helps to GIV combination code.

If you can't find the constants in REG_EQUAL notes, than some notes are
missing.  I think I've got some patches for that that are a year or two old...

: + 	  src = canon_rtx (src);

Huh?  You can't just use canon_rtx without setting up & maintaining
the reg_known_value tables.