Commit 884afaab authored Oct 23, 2008 by Nicolas Pitre Committed by Russell King Oct 23, 2008

[ARM] 5320/1: fix assembly constraints in implementation of do_div()

Those inline assembly segments using the umlal instruction must have
the & modifier so to be sure that a purely input register won't alias
one of the registers used as input+output. In most cases, the inputs
are still used after the outputs are touched, and most binutil versions
insist on "rdhi, rdlo and rm must all be different" even for ARMv6+.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

parent f80a3bb2

arch/arm/include/asm/div64.h

+3 −3

Original line number	Diff line number	Diff line
		@@ -165,7 +165,7 @@
		__res = __m; \
		asm ( "umlal %Q0, %R0, %Q1, %Q2\n\t" \
		"mov %Q0, #0" \
		: "+r" (__res) \
		: "+&r" (__res) \
		: "r" (__m), "r" (__n) \
		: "cc" ); \
		} else { \
		@@ -182,7 +182,7 @@
		"umlal %R0, %Q0, %Q1, %R2\n\t" \
		"mov %R0, #0\n\t" \
		"umlal %Q0, %R0, %R1, %R2" \
		: "+r" (__res) \
		: "+&r" (__res) \
		: "r" (__m), "r" (__n) \
		: "cc" ); \
		} else { \
		@@ -192,7 +192,7 @@
		"adds %Q0, %1, %Q0\n\t" \
		"adc %R0, %R0, #0\n\t" \
		"umlal %Q0, %R0, %R2, %R3" \
		: "+r" (__res), "+r" (__z) \
		: "+&r" (__res), "+&r" (__z) \
		: "r" (__m), "r" (__n) \
		: "cc" ); \
		} \