power4 compiling

Alan Modra amodra at bigpond.net.au
Tue Nov 4 11:23:44 EST 2003

On Mon, Nov 03, 2003 at 10:09:30AM -0600, Hollis Blanchard wrote:
> You shouldn't need to comment out tlbiel. Instead do this:
> 	CFLAGS = -mtune=power4 -Wa,-mcpu=power4
> That will tell the compiler not to use POWER4-specific instructions,
> but also tell the assembler it's ok when we use inline asm statements.

No, this is dangerous.  -mcpu=power4 tells the assembler to use the
power4 form of mtcrf if it so happens that only one field of cr is
being set.  gcc may generate such mtcrf instruction.

Alan Modra
IBM OzLabs - Linux Technology Centre

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