Re: Using GS for TLS on x86-64 for target RDOS

2013-05-15 Thread Leif Ekblad 

I made the suggested changes, and enclose a new patch.

Change log:
* gcc/config/i386/i386.c: Use DEFAULT_TLS_SEG_REG to access TLS
* gcc/config/i386/i386.h: Define default segment register for TLS
* gcc/config/i386/rdos.h: Added TLS configuration for RDOS

It's been tested with target RDOS, but not with target Linux.

Uros, could you commit the patch if it is acceptable?

Regards,
Leif Ekblad


- Original Message - 
From: Uros Bizjak ubiz...@gmail.com

To: Leif Ekblad l...@rdos.net
Cc: Michael Matz m...@suse.de; gcc-patches@gcc.gnu.org
Sent: Tuesday, May 14, 2013 8:19 PM
Subject: Re: Using GS for TLS on x86-64 for target RDOS



On Tue, May 14, 2013 at 6:45 PM, Leif Ekblad l...@rdos.net wrote:

I've made a patch along these lines  (enclosed).

Change log:
* gcc/config/i386/i386.c: Use DEFAULT_TLS_SEG_REG to access TLS
* gcc/config/i386/i386.h: Define default segment register for TLS
* gcc/config/i386/rdos.h: Added TLS configuration for RDOS


*** gcc-4.9-20130512/gcc/config/i386/i386.h2013-04-29
13:00:10.0 +0200
--- gcc-work/gcc/config/i386/i386.h2013-05-14 13:36:19.041020400 +0200

+ /* The default TLS segment register used by target.  */
+ #define DEFAULT_TLS_SEG_REG TARGET_64BIT ? SEG_FS : SEG_GS

Precedence is a bit tricky with ? ternary operand. Please put the
expression in braces...

*** gcc-4.9-20130512/gcc/config/i386/i386.c2013-05-06
16:53:03.0 +0200
--- gcc-work/gcc/config/i386/i386.c2013-05-14 13:37:14.338020400 +0200

!   || addr.seg != (DEFAULT_TLS_SEG_REG)

... and remove them there.

*** gcc-4.9-20130512/gcc/config/i386/rdos.h2013-01-28
21:42:55.0 +0100
--- gcc-work/gcc/config/i386/rdos.h2013-05-14 13:36:17.940020400 +0200

+ #undef TARGET_TLS_DIRECT_SEG_REFS
+ #define TARGET_TLS_DIRECT_SEG_REFS 1

TARGET_TLS_DIRECT_SEG_REFS_DEFAULT

! #define TARGET_OS_CPP_BUILTINS()\
!   do\
! {   \
!   builtin_define (__RDOS__);  \
!   builtin_assert (system=rdos);   \
! }   \

This looks like unwanted change to me.

The patch is OK for mainline with above changes, if tested on 
x86_64-linux-gnu.


Thanks,
Uros. 


gcc.diff
Description: Binary data

Re: Using GS for TLS on x86-64 for target RDOS

2013-05-15 Thread Uros Bizjak 
On Wed, May 15, 2013 at 9:00 PM, Leif Ekblad l...@rdos.net wrote:

 I made the suggested changes, and enclose a new patch.

...

 It's been tested with target RDOS, but not with target Linux.

 Uros, could you commit the patch if it is acceptable?

I have committed attached patch with following ChangeLog:

2013-05-15  Leif Ekblad  l...@rdos.net

* config/i386/i386.c (ix86_decompose_address): Use
DEFAULT_TLS_SEG_REG to access TLS segment register.
* config/i386/i386.h (DEFAULT_TLS_SEG_REG): New define.
* config/i386/rdos.h (DEFAULT_TLS_SEG_REG): Ditto.
(TARGET_TLS_DIRECT_SEG_REFS_DEFAULT): Ditto.

Patch was also tested on x86_64-pc-linux-gnu {,-m32}.

Uros.
Index: config/i386/i386.c
===
--- config/i386/i386.c  (revision 198944)
+++ config/i386/i386.c  (working copy)
@@ -11698,7 +11698,7 @@ ix86_decompose_address (rtx addr, struct ix86_addr
  if (XINT (op, 1) == UNSPEC_TP
   TARGET_TLS_DIRECT_SEG_REFS
   seg == SEG_DEFAULT)
-   seg = TARGET_64BIT ? SEG_FS : SEG_GS;
+   seg = DEFAULT_TLS_SEG_REG;
  else
return 0;
  break;
@@ -13650,7 +13650,7 @@ ix86_delegitimize_tls_address (rtx orig_x)
   if (GET_CODE (x) != PLUS || GET_MODE (x) != Pmode)
 return orig_x;
   if (ix86_decompose_address (x, addr) == 0
-  || addr.seg != (TARGET_64BIT ? SEG_FS : SEG_GS)
+  || addr.seg != DEFAULT_TLS_SEG_REG
   || addr.disp == NULL_RTX
   || GET_CODE (addr.disp) != CONST)
 return orig_x;
Index: config/i386/i386.h
===
--- config/i386/i386.h  (revision 198944)
+++ config/i386/i386.h  (working copy)
@@ -543,6 +543,9 @@ extern tree x86_mfence;
 /* The default abi used by target.  */
 #define DEFAULT_ABI SYSV_ABI
 
+/* The default TLS segment register used by target.  */
+#define DEFAULT_TLS_SEG_REG (TARGET_64BIT ? SEG_FS : SEG_GS)
+
 /* Subtargets may reset this to 1 in order to enable 96-bit long double
with the rounding mode forced to 53 bits.  */
 #define TARGET_96_ROUND_53_LONG_DOUBLE 0
Index: config/i386/rdos.h
===
--- config/i386/rdos.h  (revision 198944)
+++ config/i386/rdos.h  (working copy)
@@ -21,6 +21,12 @@ along with GCC; see the file COPYING3.  If not see
 #undef TARGET_EXECUTABLE_SUFFIX
 #define TARGET_EXECUTABLE_SUFFIX .exe
 
+#undef TARGET_TLS_DIRECT_SEG_REFS_DEFAULT
+#define TARGET_TLS_DIRECT_SEG_REFS_DEFAULT MASK_TLS_DIRECT_SEG_REFS
+
+#undef DEFAULT_TLS_SEG_REG
+#define DEFAULT_TLS_SEG_REG SEG_GS 
+
 #undef TARGET_RDOS
 #define TARGET_RDOS 1

Re: Using GS for TLS on x86-64 for target RDOS

2013-05-14 Thread Uros Bizjak 
Hello!

 I would need a way to use GS segment register instead of FS for x86-64 for 
 target RDOS since
 RDOS cannot use FS for TLS. It seems like the code related to this is 
 concentrated to two
 different places:

 Especially the second reference would become hard-to-read if more 
 conditionals are added to it.

 Perhaps the code could be changed to something like this:

 #ifdef TARGET_RDOS
 #define GET_TLS_SEG_REG  SEG_GS
 #else
 #define GET_TLS_SEG_REG TARGET_64BIT ? SEG_FS : SEG_GS
 #endif

 Thoughts?

I'd propose to introduce:

a) #define DEFAULT_TLS_SEG_REG in i386.h to SEG_GS

b) #undef and #define DEFAULT_TLS_SEG_REG in x86-64.h to SEG_FS

c) #undef and #define DEFAULT_TLS_SEG_REG in rdos.h to SEG_GS

Then use DEFAULT_TLS_SEG_REG everywhere.

This will avoid compile-time and runtime checks. Please note that
sequence of include files gets defined in config.gcc.

Uros.

Re: Using GS for TLS on x86-64 for target RDOS

2013-05-14 Thread Michael Matz 
Hi,

On Tue, 14 May 2013, Uros Bizjak wrote:

 I'd propose to introduce:
 
 a) #define DEFAULT_TLS_SEG_REG in i386.h to SEG_GS
 
 b) #undef and #define DEFAULT_TLS_SEG_REG in x86-64.h to SEG_FS

This would break -m32.

 c) #undef and #define DEFAULT_TLS_SEG_REG in rdos.h to SEG_GS
 
 Then use DEFAULT_TLS_SEG_REG everywhere.
 
 This will avoid compile-time and runtime checks.

... which you can't avoid in a multilib compiler.


Ciao,
Michael.

Re: Using GS for TLS on x86-64 for target RDOS

2013-05-14 Thread Uros Bizjak 
On Tue, May 14, 2013 at 11:13 AM, Michael Matz m...@suse.de wrote:

 On Tue, 14 May 2013, Uros Bizjak wrote:

 I'd propose to introduce:

 a) #define DEFAULT_TLS_SEG_REG in i386.h to SEG_GS

 b) #undef and #define DEFAULT_TLS_SEG_REG in x86-64.h to SEG_FS

 This would break -m32.

Uh, yes.

So instead of a) and b), there should be:

#define DEFAULT_TLS_SEG_REG TARGET_64BIT ? SEG_FS : SEG_GS in i386.h.

Uros.

Re: Using GS for TLS on x86-64 for target RDOS

2013-05-14 Thread Leif Ekblad 

I've made a patch along these lines  (enclosed).

Change log:
* gcc/config/i386/i386.c: Use DEFAULT_TLS_SEG_REG to access TLS
* gcc/config/i386/i386.h: Define default segment register for TLS
* gcc/config/i386/rdos.h: Added TLS configuration for RDOS

Regards,
Leif Ekblad


- Original Message - 
From: Uros Bizjak ubiz...@gmail.com

To: Michael Matz m...@suse.de
Cc: gcc-patches@gcc.gnu.org; Leif Ekblad l...@rdos.net
Sent: Tuesday, May 14, 2013 11:35 AM
Subject: Re: Using GS for TLS on x86-64 for target RDOS



On Tue, May 14, 2013 at 11:13 AM, Michael Matz m...@suse.de wrote:


On Tue, 14 May 2013, Uros Bizjak wrote:


I'd propose to introduce:

a) #define DEFAULT_TLS_SEG_REG in i386.h to SEG_GS

b) #undef and #define DEFAULT_TLS_SEG_REG in x86-64.h to SEG_FS


This would break -m32.


Uh, yes.

So instead of a) and b), there should be:

#define DEFAULT_TLS_SEG_REG TARGET_64BIT ? SEG_FS : SEG_GS in i386.h.

Uros.

gcc-tls.diff
Description: Binary data

Re: Using GS for TLS on x86-64 for target RDOS

2013-05-14 Thread Uros Bizjak 
On Tue, May 14, 2013 at 6:45 PM, Leif Ekblad l...@rdos.net wrote:
 I've made a patch along these lines  (enclosed).

 Change log:
 * gcc/config/i386/i386.c: Use DEFAULT_TLS_SEG_REG to access TLS
 * gcc/config/i386/i386.h: Define default segment register for TLS
 * gcc/config/i386/rdos.h: Added TLS configuration for RDOS

*** gcc-4.9-20130512/gcc/config/i386/i386.h2013-04-29
13:00:10.0 +0200
--- gcc-work/gcc/config/i386/i386.h2013-05-14 13:36:19.041020400 +0200

+ /* The default TLS segment register used by target.  */
+ #define DEFAULT_TLS_SEG_REG TARGET_64BIT ? SEG_FS : SEG_GS

Precedence is a bit tricky with ? ternary operand. Please put the
expression in braces...

*** gcc-4.9-20130512/gcc/config/i386/i386.c2013-05-06
16:53:03.0 +0200
--- gcc-work/gcc/config/i386/i386.c2013-05-14 13:37:14.338020400 +0200

!   || addr.seg != (DEFAULT_TLS_SEG_REG)

... and remove them there.

*** gcc-4.9-20130512/gcc/config/i386/rdos.h2013-01-28
21:42:55.0 +0100
--- gcc-work/gcc/config/i386/rdos.h2013-05-14 13:36:17.940020400 +0200

+ #undef TARGET_TLS_DIRECT_SEG_REFS
+ #define TARGET_TLS_DIRECT_SEG_REFS 1

TARGET_TLS_DIRECT_SEG_REFS_DEFAULT

! #define TARGET_OS_CPP_BUILTINS()\
!   do\
! {   \
!   builtin_define (__RDOS__);  \
!   builtin_assert (system=rdos);   \
! }   \

This looks like unwanted change to me.

The patch is OK for mainline with above changes, if tested on x86_64-linux-gnu.

Thanks,
Uros.

Using GS for TLS on x86-64 for target RDOS

2013-05-13 Thread Leif Ekblad 
I would need a way to use GS segment register instead of FS for x86-64 for 
target RDOS since RDOS cannot use FS for TLS. It seems like the code related 
to this is concentrated to two different places:


The gcc/config/i386/i386.c:
11677:seg = TARGET_64BIT ? SEG_FS : SEG_GS;
13526:  if (ix86_decompose_address (x, addr) == 0
 || addr.seg != (TARGET_64BIT ? SEG_FS : SEG_GS)
 || addr.disp == NULL_RTX
 || GET_CODE (addr.disp) != CONST)

Especially the second reference would become hard-to-read if more 
conditionals are added to it.


Perhaps the code could be changed to something like this:

#ifdef TARGET_RDOS
#define GET_TLS_SEG_REG  SEG_GS
#else
#define GET_TLS_SEG_REG TARGET_64BIT ? SEG_FS : SEG_GS
#endif

Then the above could be patched to:
11677:seg = GET_TLS_SEG_REG;
13526:  if (ix86_decompose_address (x, addr) == 0
 || addr.seg != (GET_TLS_SEG_REG)
 || addr.disp == NULL_RTX
 || GET_CODE (addr.disp) != CONST)

Thoughts?

Regards,
Leif Ekblad