[PATCH 3.19 080/175] MIPS: asm: asmmacro: Replace "add" instructions with "addu"

Greg Kroah-Hartman
2015-03-04T06:51:42Z

From: Markos Chandras <markos.chandras@imgtec.com>

commit 98a833c1fa4de0695830f77b2d13fd86693da298 upstream.

The "add" instruction is actually a macro in binutils and depending on
the size of the immediate it can expand to an "addi" instruction.
However, the "addi" instruction traps on overflows which is not
something we want on address calculation.

Link: http://www.linux-mips.org/archives/linux-mips/2015-01/msg00121.html
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/mips/include/asm/asmmacro.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/mips/include/asm/asmmacro.h
+++ b/arch/mips/include/asm/asmmacro.h
@@ -304,7 +304,7 @@
.set push
.set noat
SET_HARDFLOAT
- add $1, \base, \off
+ addu $1, \base, \off
.word LDD_MSA_INSN | (\wd << 6)
.set pop
.endm
@@ -313,7 +313,7 @@
.set push
.set noat
SET_HARDFLOAT
- add $1, \base, \off
+ addu $1, \base, \off
.word STD_MSA_INSN | (\wd << 6)
.set pop
.endm