[Bug target/20263] New: Incorrect asm for global register vars on sparc64

[Bug target/20263] New: Incorrect asm for global register vars on sparc64

[gcc-bugzilla at gcc dot gnu dot org]

Using a global variable tied to register g7 generates invalid assembly
code on sparc64.

Consider:

    register void *tp __asm__("%g7");

    void set_tp() {
	tp = 0;
    }

Compiling this file produces an error and a warning from the assembler:

    /usr/ccs/bin/as: "/var/tmp//ccLsIpQg.s", line 2: error: statement syntax
    /usr/ccs/bin/as: "/var/tmp//ccLsIpQg.s", line 10: warning: detect global register use not covered .register pseudo-op

Environment:
System: SunOS plg2.math 5.8 Generic_117350-18 sun4u sparc SUNW,Sun-Fire-880
Architecture: sun4
host: sparc64-sun-solaris2.8
build: sparc64-sun-solaris2.8
target: sparc64-sun-solaris2.8
configured with: ../gcc/configure --prefix=/u/rcbilson/software/gcc --enable-languages=c,c++ sparc64-sun-solaris2.8

How-To-Repeat:
Attempt to compile the above program fragment.
------- Additional Comments From rcbilson at plg dot uwaterloo dot ca  2005-03-01 16:45 -------
Fix:
Examining the -S output shows that the .register op generated by the
compiler is

    .register       %g7, %g7

The second operand seems to be incorrect -- it ought to be a plain
name, not a register name.  Replacing this op with

    .register       %g7, g7

allows the code to assemble, eliminating both the error and the
warning.

I don't know enough about .register to be confident in suggesting an
appropriate identifier to use for the second operand.

-- 
           Summary: Incorrect asm for global register vars on sparc64
           Product: gcc
           Version: 1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rcbilson at plg dot uwaterloo dot ca
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: sparc64-sun-solaris2.8
  GCC host triplet: sparc64-sun-solaris2.8
GCC target triplet: sparc64-sun-solaris2.8


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug target/20263] Incorrect asm for global register vars on sparc64

[rcbilson at plg dot uwaterloo dot ca]

------- Additional Comments From rcbilson at plg dot uwaterloo dot ca  2005-03-01 16:50 -------
I seem to have screwed something up in gccbug -- this is not a 2.95 issue.  I've
encoundered this problem with 3.4.3 and with the Feb. 28 mainline CVS version.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|1.0                         |2.95


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug target/20263] Incorrect asm for global register vars on sparc64

[rcbilson at plg dot uwaterloo dot ca]

------- Additional Comments From rcbilson at plg dot uwaterloo dot ca  2005-03-01 16:52 -------
Attempting to change "Reported against"...

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|2.95                        |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug target/20263] Incorrect asm for global register vars on sparc64

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-03-01 17:47 -------
Confirmed, we just forgot to remove the % from NAME when outputing it.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
  GCC build triplet|sparc64-sun-solaris2.8      |
   GCC host triplet|sparc64-sun-solaris2.8      |
 GCC target triplet|sparc64-sun-solaris2.8      |sparc64-*-*
           Keywords|                            |wrong-code
   Last reconfirmed|0000-00-00 00:00:00         |2005-03-01 17:47:28
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug target/20263] Incorrect asm for global register vars on sparc64

[ebotcazou at gcc dot gnu dot org]

------- Additional Comments From ebotcazou at gcc dot gnu dot org  2005-03-01 19:52 -------
Fixing.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |ebotcazou at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug target/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[ebotcazou at gcc dot gnu dot org]

------- Additional Comments From ebotcazou at gcc dot gnu dot org  2005-03-16 07:56 -------
The problem occurs only with GCC 4.x, in particular not with GCC 3.4.3.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Incorrect asm for global    |[4.0/4.1 Regression]
                   |register vars on sparc64    |Incorrect asm for global
                   |                            |register vars
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[ebotcazou at gcc dot gnu dot org]

------- Additional Comments From ebotcazou at gcc dot gnu dot org  2005-03-16 09:01 -------
Recategorizing.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|target                      |middle-end


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[rcbilson at plg dot uwaterloo dot ca]

------- Additional Comments From rcbilson at plg dot uwaterloo dot ca  2005-03-16 15:12 -------
(In reply to comment #6)
> The problem occurs only with GCC 4.x, in particular not with GCC 3.4.3.

This was strange to read, because I've definitely noticed it with 3.4.3.
Interestingly, it seems to be only g++, rather than gcc, that has the problem:

plg2=; cat g7.c
register void *tp __asm__("%g7");

void set_tp() {
    tp = 0;
}
plg2=; gcc -S g7.c
plg2=; grep register g7.s
	.register	%g7, tp
plg2=; g++ -S g7.c
plg2=; grep register g7.s
	.register	%g7, %g7
plg2=; gcc -v
Reading specs from
/fsys2/u2/asharji/gcc/gcc-3.4.3/bin/../lib/gcc/sparc64-sun-solaris2.8/3.4.3/specs
Configured with: ../src/configure --prefix=/u/asharji/gcc/gcc-3.4.3
--enable-languages=c,c++ sparc64-sun-solaris2.8
Thread model: posix
gcc version 3.4.3
plg2=; g++ -v
Reading specs from
/fsys2/u2/asharji/gcc/gcc-3.4.3/bin/../lib/gcc/sparc64-sun-solaris2.8/3.4.3/specs
Configured with: ../src/configure --prefix=/u/asharji/gcc/gcc-3.4.3
--enable-languages=c,c++ sparc64-sun-solaris2.8
Thread model: posix
gcc version 3.4.3


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[ebotcazou at gcc dot gnu dot org]

------- Additional Comments From ebotcazou at gcc dot gnu dot org  2005-03-16 15:55 -------
> This was strange to read, because I've definitely noticed it with 3.4.3.
> Interestingly, it seems to be only g++, rather than gcc, that has the problem:
> 
> plg2=; cat g7.c
> register void *tp __asm__("%g7");
> 
> void set_tp() {
>     tp = 0;
> }
> plg2=; gcc -S g7.c
> plg2=; grep register g7.s
> 	.register	%g7, tp
> plg2=; g++ -S g7.c
> plg2=; grep register g7.s
> 	.register	%g7, %g7

Oh! Yes, you right.  The patch has already been posted, I'll try to have it
installed on the 3.4 branch too:
http://gcc.gnu.org/ml/gcc-patches/2005-03/msg01529.html


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[mmitchel at gcc dot gnu dot org]

------- Additional Comments From mmitchel at gcc dot gnu dot org  2005-03-24 19:08 -------
Wouldn't it be better to have DECL_ASSEMBLER_NAME use the real name?  What's the
background onthe change to DECL_ASSEMBLER_NAME?

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[ebotcazou at gcc dot gnu dot org]

------- Additional Comments From ebotcazou at gcc dot gnu dot org  2005-03-24 22:24 -------
> Wouldn't it be better to have DECL_ASSEMBLER_NAME use the real name?  What's the
> background onthe change to DECL_ASSEMBLER_NAME?

Define "real name".  In 3.4.x, as discovered by Richard, the C and C++ compilers
disagree on DECL_ASSEMBLER_NAME for register variables.  In 4.x, the C compiler
has been changed to use the C++ idiom that seems more sensible to me: DECL_NAME
is the name of the declared variable ("tp") while DECL_ASSEMBLER_NAME is the
name of the variable as written in the assembly file ("%g7").

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-03-29 12:09 -------
Subject: Bug 20263

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	ebotcazou@gcc.gnu.org	2005-03-29 12:08:55

Modified files:
	gcc            : ChangeLog varasm.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/gcc.dg: sparc-reg-1.c 

Log message:
	PR middle-end/20263
	* varasm.c (make_decl_rtl) [ASM_DECLARE_REGISTER_GLOBAL]: Use
	the DECL_NAME, not the DECL_ASSEMBLER_NAME.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.8009&r2=2.8010
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/varasm.c.diff?cvsroot=gcc&r1=1.486&r2=1.487
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.5229&r2=1.5230
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/sparc-reg-1.c.diff?cvsroot=gcc&r1=NONE&r2=1.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-03-29 12:18 -------
Subject: Bug 20263

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	gcc-4_0-branch
Changes by:	ebotcazou@gcc.gnu.org	2005-03-29 12:16:41

Modified files:
	gcc            : ChangeLog varasm.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/gcc.dg: sparc-reg-1.c 

Log message:
	PR middle-end/20263
	* varasm.c (make_decl_rtl) [ASM_DECLARE_REGISTER_GLOBAL]: Use
	the DECL_NAME, not the DECL_ASSEMBLER_NAME.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-4_0-branch&r1=2.7592.2.87&r2=2.7592.2.88
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/varasm.c.diff?cvsroot=gcc&only_with_tag=gcc-4_0-branch&r1=1.477.6.3&r2=1.477.6.4
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-4_0-branch&r1=1.5084.2.72&r2=1.5084.2.73
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/sparc-reg-1.c.diff?cvsroot=gcc&only_with_tag=gcc-4_0-branch&r1=NONE&r2=1.1.2.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263

[Bug middle-end/20263] [4.0/4.1 Regression] Incorrect asm for global register vars

[ebotcazou at gcc dot gnu dot org]

------- Additional Comments From ebotcazou at gcc dot gnu dot org  2005-03-29 12:23 -------
Fixed in 4.x.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20263