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[SCSI] ultrastor: clean up inline asm warnings

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To: [email protected]
Cc: [email protected]
Subject: [trivial patch] scsi/ultrastor: clean up inline asm warnings

Hi,

Compiling latest mainline with gcc 4.2.1 spews the following warnings:

drivers/scsi/ultrastor.c: In function 'find_and_clear_bit_16':
drivers/scsi/ultrastor.c:303: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:302: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c: At top level:
drivers/scsi/ultrastor.c:1202: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:1202: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c: In function 'ultrastor_queuecommand':
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:698: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:302: warning: matching constraint does not allow a register
drivers/scsi/ultrastor.c:302: warning: matching constraint does not allow a register

The following patch fixes it by using the '+' operator on the (*field)
operand, marking it as read-write to gcc. I diffed the two resulting .s,
and gcc produced the same code. This was tested with gcc 4.2.1 and gcc 3.4.3

Signed-off-by: Frederik Deweerdt <[email protected]>
Cc: Adrian Bunk <[email protected]>
Signed-off-by: James Bottomley <[email protected]>
This commit is contained in:
Frederik Deweerdt
2008-01-25 11:09:10 -06:00
committed by James Bottomley
parent 93a38fa2dd
commit 1292500b15
1 changed files with 10 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/scsi/ultrastor.c
+10 -3
View File
@@ -298,9 +298,16 @@ static inline int find_and_clear_bit_16(unsigned long *field)
{ {
int rv; int rv;
if (*field == 0) panic("No free mscp"); if (*field == 0)
asm("xorl %0,%0\n0:\tbsfw %1,%w0\n\tbtr %0,%1\n\tjnc 0b" panic("No free mscp");
: "=&r" (rv), "=m" (*field) : "1" (*field));
asm volatile (
"xorl %0,%0\n\t"
"0: bsfw %1,%w0\n\t"
"btr %0,%1\n\t"
"jnc 0b"
: "=&r" (rv), "=m" (*field) :);
return rv; return rv;
} }