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SUBREG_BYTE question
- From: Bernd Schmidt <bernds at redhat dot com>
- To: <gcc at gcc dot gnu dot org>
- Date: Tue, 26 Feb 2002 13:35:35 +0000 (GMT)
- Subject: SUBREG_BYTE question
I need to know the exact meaning of the SUBREG_BYTE field of a SUBREG.
Suppose I have a big-endian target, an SImode (which is the word size)
register, and I want to use the part of the register in a narrower mode.
Should SUBREG_BYTE be zero, or should it be equal to the offset that
would be used if the value were in memory?
The problem I have is that I've got two testcases, and in one of these I
get (subreg:HI (reg:SI xyz) 0) for the lowpart, and in the other I get
(subreg:QI (reg:SI abc) 3). Fixing one breaks the other. Which one is
correct?
Bernd