ldrex/strex syntax errors with recent compilers

PATCH In review Stelian Pop 3 participants 4 messages Mar 15, 2007 – Mar 18, 2007 Atomic infrastructure

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Stelian Pop

author

2007-03-15 13:53 UTC #0 lore raw

PATCH 1/1 ldrex/strex syntax errors with recent compilers

Hi,

Trying to build a xenomai-enabled kernel using a recent compiler (tried with gcc version 4.1.1 (CodeSourcery ARM Sourcery G++ 2006q3-26), but all gcc > 4.1 might be affected) results in the following:

CC kernel/xenomai/nucleus/shadow.o
/tmp/cc0XooxH.s: Assembler messages:
/tmp/cc0XooxH.s:1464: Error: instruction does not accept this addressing mode -- ldrex r1,r2' /tmp/cc0XooxH.s:1466: Error: instruction does not accept this addressing mode -- strex r3,r1,r2'

Older gcc (like gcc version 4.0.0 (DENX ELDK 4.1 4.0.0)) have no problem with this.

It appears that the patch below fixes the compile error. I also verified that gcc-4.0.0 generates identical code using both forms.

asm-arm/atomic.h +6 -6

Index: include/asm-arm/atomic.h
===================================================================
@@ -40,9 +40,9 @@
     unsigned long tmp, tmp2;
 
     __asm__ __volatile__("@ atomic_set_mask\n"
-"1: ldrex   %0, %2\n"
+"1: ldrex   %0, [%2]\n"
 "   orr     %0, %0, %3\n"
-"   strex   %1, %0, %2\n"
+"   strex   %1, %0, [%2]\n"
 "   teq     %1, #0\n"
 "   bne     1b"
     : "=&r" (tmp), "=&r" (tmp2)

@@ -170,9 +170,9 @@
     unsigned long tmp, tmp2;
 
     __asm__ __volatile__("@ atomic_set_mask\n"
-"1: ldrex   %0, %2\n"
+"1: ldrex   %0, [%2]\n"
 "   orr     %0, %0, %3\n"
-"   strex   %1, %0, %2\n"
+"   strex   %1, %0, [%2]\n"
 "   teq     %1, #0\n"
 "   bne     1b"
     : "=&r" (tmp), "=&r" (tmp2)

@@ -185,9 +185,9 @@
     unsigned long tmp, tmp2;
 
     __asm__ __volatile__("@ atomic_clear_mask\n"
-"1: ldrex   %0, %2\n"
+"1: ldrex   %0, [%2]\n"
 "   bic     %0, %0, %3\n"
-"   strex   %1, %0, %2\n"
+"   strex   %1, %0, [%2]\n"
 "   teq     %1, #0\n"
 "   bne     1b"
     : "=&r" (tmp), "=&r" (tmp2)

Signature · 1 line

Stelian Pop <[email protected]>

Stelian Pop

2007-03-15 13:57 UTC #1 lore raw

PATCH 1/1 ldrex/strex syntax errors with recent compilers

Le jeudi 15 mars 2007 à 14:53 +0100, Stelian Pop a écrit :

[on xenomai-core ml]

Quoted 11 lines

Hi,
Trying to build a xenomai-enabled kernel using a recent compiler (tried with gcc version 4.1.1 (CodeSourcery ARM Sourcery G++ 2006q3-26), but all gcc > 4.1 might be affected) results in the following:
CC kernel/xenomai/nucleus/shadow.o
/tmp/cc0XooxH.s: Assembler messages:
/tmp/cc0XooxH.s:1464: Error: instruction does not accept this addressing mode -- ldrex r1,r2' /tmp/cc0XooxH.s:1466: Error: instruction does not accept this addressing mode -- strex r3,r1,r2'

Quoted 4 lines

Older gcc (like gcc version 4.0.0 (DENX ELDK 4.1 4.0.0)) have no problem with this.
It appears that the patch below fixes the compile error. I also verified that gcc-4.0.0 generates identical code using both forms.

The same issue is present in the mainline kernel too. I'll report this on LKML but meanwhile the patch below could be included in the Adeos patch as well...

Thanks.

Stelian.

include/asm-arm/atomic.h +2 -2

index c86c3d0..5dda903 100644
@@ -103,9 +103,9 @@ static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 	unsigned long tmp, tmp2;
 
 	__asm__ __volatile__("@ atomic_clear_mask\n"
-"1:	ldrex	%0, %2\n"
+"1:	ldrex	%0, [%2]\n"
 "	bic	%0, %0, %3\n"
-"	strex	%1, %0, %2\n"
+"	strex	%1, %0, [%2]\n"
 "	teq	%1, #0\n"
 "	bne	1b"
 	: "=&r" (tmp), "=&r" (tmp2)

Signature · 1 line

Stelian Pop <[email protected]>

Gilles Chanteperdrix

Applied

2007-03-18 16:18 UTC #2 lore raw

Quoted 14 lines · Stelian Pop

Le jeudi 15 mars 2007 ~ 14:53 +0100, Stelian Pop a ~crit :
[on xenomai-core ml]
Quoted 11 lines
Hi,
Trying to build a xenomai-enabled kernel using a recent compiler (tried with gcc version 4.1.1 (CodeSourcery ARM Sourcery G++ 2006q3-26), but all gcc > 4.1 might be affected) results in the following:
CC kernel/xenomai/nucleus/shadow.o
/tmp/cc0XooxH.s: Assembler messages:
/tmp/cc0XooxH.s:1464: Error: instruction does not accept this addressing mode -- ldrex r1,r2' /tmp/cc0XooxH.s:1466: Error: instruction does not accept this addressing mode -- strex r3,r1,r2'

Quoted 8 lines

Quoted 4 lines
Older gcc (like gcc version 4.0.0 (DENX ELDK 4.1 4.0.0)) have no problem with this.
It appears that the patch below fixes the compile error. I also verified that gcc-4.0.0 generates identical code using both forms.
The same issue is present in the mainline kernel too. I'll report this on LKML but meanwhile the patch below could be included in the Adeos patch as well...

Applied all your patches. Thanks.

Signature · 1 line

					    Gilles Chanteperdrix.

Stelian Pop

author

2007-03-15 16:02 UTC #3 lore raw

In reply to Stelian Pop

Quoted 2 lines · Stelian Pop

It appears that the patch below fixes the compile error. I also verified that gcc-4.0.0 generates identical code using both forms.

FWIW, the same fix at a different place in the mainline kernel has been acked by Catalin Marinas from ARM.

Ah, and the patch I submitted was against the 2.3.x branch although it will probably apply more or less cleanly on trunk.

Thanks,

Signature · 1 line

Stelian Pop <[email protected]>