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Re: 32->64 bit cross compilers
- To: aoliva at redhat dot com (Alexandre Oliva)
- Subject: Re: 32->64 bit cross compilers
- From: Joern Rennecke <amylaar at redhat dot com>
- Date: Wed, 6 Jun 2001 22:05:08 +0100 (BST)
- Cc: mark at codesourcery dot com (Mark Mitchell), janis at us dot ibm dot com,gcc at gcc dot gnu dot org, gcc-patches at gcc dot gnu dot org, kenner at vlsi1 dot ultra dot nyu dot edu
> I'm not really sure we'd end up generating bad code. I don't recall
> having seen any situation in which we'd generate bad code because of
> missing sign-extension in CONST_INTs, but it may be that I just didn't
> search enough. But NOT installing the strict checking patches in the
> branch will certainly reduce the overall risk.
I do remember having seen such cases, but they are extremely rare.
Strength reduction failures happen more often.
OTOH, occurences of constants that are not sign-extended according to the
new rules are quite common. In particular in small modes, like 8 and 16 bit.