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Re: RFA: Fix regrename bug for multi-register values

Daniel Jacobowitz wrote:

I have a testcase for GCC 3.3.1 in which a DFmode value (arm-elf,
-msoft-float) is allocated to registers fp and ip.  Fp is call-saved, but ip
is call-clobbered.  Regrename copyprops this value across a CALL_INSN,
because calling kill_value_regno (IP_REGNUM, vd) doesn't kill a two-register
value living in FP_REGNUM.

I can't reproduce the bug in 3.4 or HEAD, but the bad code is still there.
Patch OK?


I'm going to call that pretty much obviously correct, as long as you've tested it somewhere.

I think it would be mildly clearer to pass the mode (rather than the number of registers) to kill_value_regno, and let it do the hard_regno_regs thing itself; that makes the function a little more abstract. So, please make that change as well.

--
Mark Mitchell
CodeSourcery, LLC
(916) 791-8304
mark@codesourcery.com

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