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From: "Zvilius, Mark" <Mark.Zvilius@fluke.com>
To: "'gcc-help@gcc.gnu.org'" <gcc-help@gcc.gnu.org>
Subject: asm constraints
Date: Fri, 27 Aug 2004 06:58:00 -0000
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For a PowerPC architecture I'm using the following asm statement in C source
to read a time base register:

	unsigned int tbl;
	__asm__("mftbl %0" : "=r" (tbl));

The code this generates is:
	mftb   r0
	mr     r9,r0
	stw    r9,0x18(r31)

I'm wondering why it's wasting a register. Am I specifying the constraint
incorrectly?

Mark Z.