[mythtv] [patch] mythmusic compile problem

Daniel Thor Kristjansson danielk at cat.nyu.edu
Thu Feb 19 16:25:20 EST 2004


It's a bug. It just slips by gcc when the operand has spilled to memory
instead of being in an MMX register. Changing the "X" to an "m"
explicitly tells gcc that it must be in memory. It might be faster in
some cases to do a "movd X, r" instead of going to memory, but that is
something the person that maintains the code should do. You really have
to test to see if that is faster, since a mov to memory and back to a
register is faster when forwarding is working.

-- Daniel
  << When truth is outlawed; only outlaws will tell the truth. >> - RLiegh

On Thu, 19 Feb 2004, Matt Zimmerman wrote:

]On Thu, Feb 19, 2004 at 01:30:21PM -0500, Daniel Thor Kristjansson wrote:
]
]>
]> Tiny patch that fixes an MMX error that prevents mythmusic from
]> compiling with gcc 3.3.2. Basically the source was specified as a MMX
]> register for a normal 32 bit addl. I changed the source type to memory,
]> which will generate correct code.
]
]It compiles fine for me here:
]
]gcc version 3.3.3 (Debian)
]
]I'm pretty MMX-ignorant; is this clearly a bug in the code, or potentially a
]gcc problem?
]
]


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