This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: ssa bootstrap problem on x86 (cmpstrsi_1 pattern)
- To: Mark Mitchell <mark at codesourcery dot com>
- Subject: Re: ssa bootstrap problem on x86 (cmpstrsi_1 pattern)
- From: Joern Rennecke <amylaar at cygnus dot co dot uk>
- Date: Fri, 28 Jul 2000 00:59:55 +0100 (BST)
- CC: geoffk at cygnus dot com, gcc at gcc dot gnu dot org
> The only reason clobbers appear this early in the compiler is that GCC
> generates machine-specific code very early. There is no operation
That is not true. When gcc synthesizes a move that is wider than the
widest one available in the machine description, it first clobbers the
destination, then does a series of moves into SUBREGs of the destination.