[PATCH-ppc 2/5] Add VSX support for core-files

[PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

This patch adds the required support to dump VSX registers and read them
them back from a specific VSX notes section. This is in sync with the
format used by the Kernel.

--- 
2008-07-25  Luis Machado  <luisgpm@br.ibm.com>

	* ppc-linux-tdep.c (ppc_linux_regset_sections): Add new ".reg-ppc-vsx" field.
	(ppc32_linux_vsxregset): New 32-bit VSX-enabled regset.
	(ppc_linux_regset_from_core_section): Handle VSX core section.
	(ppc_linux_core_read_description): Support VSX-enabled core files.

	* corelow.c (get_core_register_section): Support VSX-enabled 
	core files.


Index: gdb/ppc-linux-tdep.c
===================================================================
--- gdb.orig/ppc-linux-tdep.c	2008-07-23 09:28:09.000000000 -0700
+++ gdb/ppc-linux-tdep.c	2008-07-23 09:31:44.000000000 -0700
@@ -496,6 +496,7 @@
   { ".reg", 268 },
   { ".reg2", 264 },
   { ".reg-ppc-vmx", 544 },
+  { ".reg-ppc-vsx", 256 },
   { NULL, 0}
 };
 
@@ -743,6 +744,13 @@
   NULL
 };
 
+static const struct regset ppc32_linux_vsxregset = {
+  &ppc32_linux_reg_offsets,
+  ppc_supply_vsxregset,
+  ppc_collect_vsxregset,
+  NULL
+};
+
 const struct regset *
 ppc_linux_gregset (int wordsize)
 {
@@ -771,6 +779,8 @@
     return &ppc32_linux_fpregset;
   if (strcmp (sect_name, ".reg-ppc-vmx") == 0)
     return &ppc32_linux_vrregset;
+  if (strcmp (sect_name, ".reg-ppc-vsx") == 0)
+    return &ppc32_linux_vsxregset;
   return NULL;
 }
 
@@ -974,6 +984,7 @@
 				 bfd *abfd)
 {
   asection *altivec = bfd_get_section_by_name (abfd, ".reg-ppc-vmx");
+  asection *vsx = bfd_get_section_by_name (abfd, ".reg-ppc-vsx");
   asection *section = bfd_get_section_by_name (abfd, ".reg");
   if (! section)
     return NULL;
@@ -981,10 +992,20 @@
   switch (bfd_section_size (abfd, section))
     {
     case 48 * 4:
-      return altivec? tdesc_powerpc_altivec32l : tdesc_powerpc_32l;
+      if (vsx)
+	return tdesc_powerpc_vsx32l;
+      else if (altivec)
+	return tdesc_powerpc_altivec32l;
+      else
+	return tdesc_powerpc_32l;
 
     case 48 * 8:
-      return altivec? tdesc_powerpc_altivec64l : tdesc_powerpc_64l;
+      if (vsx)
+	return tdesc_powerpc_vsx64l;
+      else if (altivec)
+	return tdesc_powerpc_altivec64l;
+      else
+	return tdesc_powerpc_64l;
 
     default:
       return NULL;
Index: gdb/corelow.c
===================================================================
--- gdb.orig/corelow.c	2008-07-23 09:28:09.000000000 -0700
+++ gdb/corelow.c	2008-07-23 09:31:44.000000000 -0700
@@ -499,6 +499,8 @@
 			     ".reg-xfp", 3, "extended floating-point", 0);
   get_core_register_section (regcache,
   			     ".reg-ppc-vmx", 3, "ppc Altivec", 0);
+  get_core_register_section (regcache,
+			     ".reg-ppc-vsx", 4, "POWER7 VSX", 0);
 
   /* Supply dummy value for all registers not found in the core.  */
   for (i = 0; i < gdbarch_num_regs (get_regcache_arch (regcache)); i++)

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

Ping?

On Fri, 2008-07-25 at 17:15 -0300, Luis Machado wrote:
> This patch adds the required support to dump VSX registers and read them
> them back from a specific VSX notes section. This is in sync with the
> format used by the Kernel.
> 
> --- 
> 2008-07-25  Luis Machado  <luisgpm@br.ibm.com>
> 
> 	* ppc-linux-tdep.c (ppc_linux_regset_sections): Add new ".reg-ppc-vsx" field.
> 	(ppc32_linux_vsxregset): New 32-bit VSX-enabled regset.
> 	(ppc_linux_regset_from_core_section): Handle VSX core section.
> 	(ppc_linux_core_read_description): Support VSX-enabled core files.
> 
> 	* corelow.c (get_core_register_section): Support VSX-enabled 
> 	core files.
> 
> 
> Index: gdb/ppc-linux-tdep.c
> ===================================================================
> --- gdb.orig/ppc-linux-tdep.c	2008-07-23 09:28:09.000000000 -0700
> +++ gdb/ppc-linux-tdep.c	2008-07-23 09:31:44.000000000 -0700
> @@ -496,6 +496,7 @@
>    { ".reg", 268 },
>    { ".reg2", 264 },
>    { ".reg-ppc-vmx", 544 },
> +  { ".reg-ppc-vsx", 256 },
>    { NULL, 0}
>  };
> 
> @@ -743,6 +744,13 @@
>    NULL
>  };
> 
> +static const struct regset ppc32_linux_vsxregset = {
> +  &ppc32_linux_reg_offsets,
> +  ppc_supply_vsxregset,
> +  ppc_collect_vsxregset,
> +  NULL
> +};
> +
>  const struct regset *
>  ppc_linux_gregset (int wordsize)
>  {
> @@ -771,6 +779,8 @@
>      return &ppc32_linux_fpregset;
>    if (strcmp (sect_name, ".reg-ppc-vmx") == 0)
>      return &ppc32_linux_vrregset;
> +  if (strcmp (sect_name, ".reg-ppc-vsx") == 0)
> +    return &ppc32_linux_vsxregset;
>    return NULL;
>  }
> 
> @@ -974,6 +984,7 @@
>  				 bfd *abfd)
>  {
>    asection *altivec = bfd_get_section_by_name (abfd, ".reg-ppc-vmx");
> +  asection *vsx = bfd_get_section_by_name (abfd, ".reg-ppc-vsx");
>    asection *section = bfd_get_section_by_name (abfd, ".reg");
>    if (! section)
>      return NULL;
> @@ -981,10 +992,20 @@
>    switch (bfd_section_size (abfd, section))
>      {
>      case 48 * 4:
> -      return altivec? tdesc_powerpc_altivec32l : tdesc_powerpc_32l;
> +      if (vsx)
> +	return tdesc_powerpc_vsx32l;
> +      else if (altivec)
> +	return tdesc_powerpc_altivec32l;
> +      else
> +	return tdesc_powerpc_32l;
> 
>      case 48 * 8:
> -      return altivec? tdesc_powerpc_altivec64l : tdesc_powerpc_64l;
> +      if (vsx)
> +	return tdesc_powerpc_vsx64l;
> +      else if (altivec)
> +	return tdesc_powerpc_altivec64l;
> +      else
> +	return tdesc_powerpc_64l;
> 
>      default:
>        return NULL;
> Index: gdb/corelow.c
> ===================================================================
> --- gdb.orig/corelow.c	2008-07-23 09:28:09.000000000 -0700
> +++ gdb/corelow.c	2008-07-23 09:31:44.000000000 -0700
> @@ -499,6 +499,8 @@
>  			     ".reg-xfp", 3, "extended floating-point", 0);
>    get_core_register_section (regcache,
>    			     ".reg-ppc-vmx", 3, "ppc Altivec", 0);
> +  get_core_register_section (regcache,
> +			     ".reg-ppc-vsx", 4, "POWER7 VSX", 0);
> 
>    /* Supply dummy value for all registers not found in the core.  */
>    for (i = 0; i < gdbarch_num_regs (get_regcache_arch (regcache)); i++)
> 
> 

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Ulrich Weigand]

Luis Machado wrote:

> >    { ".reg", 268 },
> >    { ".reg2", 264 },
> >    { ".reg-ppc-vmx", 544 },
> > +  { ".reg-ppc-vsx", 256 },
> >    { NULL, 0}

This patch seems to cause a testsuite regression: generate-core-file
will now *always* add a VSX section, even if the current target does
not actually support VSX registers.  Therefore, on reading the core
file back in, the output of "info all-registers" is different than
before.

I think you should install different versions of ppc_linux_regset_sections
depending on the target properties (which you can inspect via
tdesc_find_feature (info.target_desc, ...) in ppc_linux_init_abi.

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

On Thu, 2008-08-21 at 21:52 +0200, Ulrich Weigand wrote:
> Luis Machado wrote:
> 
> > >    { ".reg", 268 },
> > >    { ".reg2", 264 },
> > >    { ".reg-ppc-vmx", 544 },
> > > +  { ".reg-ppc-vsx", 256 },
> > >    { NULL, 0}
> 
> This patch seems to cause a testsuite regression: generate-core-file
> will now *always* add a VSX section, even if the current target does
> not actually support VSX registers.  Therefore, on reading the core
> file back in, the output of "info all-registers" is different than
> before.
> 
> I think you should install different versions of ppc_linux_regset_sections
> depending on the target properties (which you can inspect via
> tdesc_find_feature (info.target_desc, ...) in ppc_linux_init_abi.
> 
> Bye,
> Ulrich

Yes. I think this is currently expected given the current code. 

For example, the core file generated with "gcore" on a 440 system will
dump VMX registers as well, and that target doesn't even have VMX
registers there. 

A new check should suffice for that. We will need three kinds of sets
then: VSX-able, VMX-able and neither VSX or VMX. How does it sound?

Regards,
Luis

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Ulrich Weigand]

Luis Machado wrote:

> A new check should suffice for that. We will need three kinds of sets
> then: VSX-able, VMX-able and neither VSX or VMX. How does it sound?

That sounds right.

Thanks,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

Hi,

Attached is a patch that fixes the seen regression. OK?

Thanks,
Luis

On Thu, 2008-08-21 at 23:13 +0200, Ulrich Weigand wrote:
> Luis Machado wrote:
> 
> > A new check should suffice for that. We will need three kinds of sets
> > then: VSX-able, VMX-able and neither VSX or VMX. How does it sound?
> 
> That sounds right.
> 
> Thanks,
> Ulrich
> 

---

2008-08-22  Luis Machado  <luisgpm@br.ibm.com>

	* ppc-linux-tdep.c (ppc_linux_vsx_regset_sections) New structure.
	(ppc_linux_vmx_regset_sections): New structure.
	(ppc_linux_fp_regset_sections): New structure.
	(ppc_linux_init_abi): Select core-file regset  based on target
	features.
	
Index: gdb/ppc-linux-tdep.c
===================================================================
--- gdb.orig/ppc-linux-tdep.c	2008-08-22 15:12:04.000000000 -0700
+++ gdb/ppc-linux-tdep.c	2008-08-22 15:22:42.000000000 -0700
@@ -491,7 +491,7 @@
   return ppc64_desc_entry_point (desc);
 }
 
-static struct core_regset_section ppc_linux_regset_sections[] =
+static struct core_regset_section ppc_linux_vsx_regset_sections[] =
 {
   { ".reg", 268 },
   { ".reg2", 264 },
@@ -500,6 +500,21 @@
   { NULL, 0}
 };
 
+static struct core_regset_section ppc_linux_vmx_regset_sections[] =
+{
+  { ".reg", 268 },
+  { ".reg2", 264 },
+  { ".reg-ppc-vmx", 544 },
+  { NULL, 0}
+};
+
+static struct core_regset_section ppc_linux_fp_regset_sections[] =
+{
+  { ".reg", 268 },
+  { ".reg2", 264 },
+  { NULL, 0}
+};
+
 static CORE_ADDR
 ppc64_standard_linkage2_target (struct frame_info *frame,
 				CORE_ADDR pc, unsigned int *insn)
@@ -1103,7 +1118,14 @@
   set_gdbarch_core_read_description (gdbarch, ppc_linux_core_read_description);
 
   /* Supported register sections.  */
-  set_gdbarch_core_regset_sections (gdbarch, ppc_linux_regset_sections);
+  if (tdesc_find_feature (info.target_desc,
+			  "org.gnu.gdb.power.vsx"))
+    set_gdbarch_core_regset_sections (gdbarch, ppc_linux_vsx_regset_sections);
+  else if (tdesc_find_feature (info.target_desc,
+			       "org.gnu.gdb.power.altivec"))
+    set_gdbarch_core_regset_sections (gdbarch, ppc_linux_vmx_regset_sections);
+  else
+    set_gdbarch_core_regset_sections (gdbarch, ppc_linux_fp_regset_sections);
 
   /* Enable TLS support.  */
   set_gdbarch_fetch_tls_load_module_address (gdbarch,

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Ulrich Weigand]

Luis Machado wrote:

> 	* ppc-linux-tdep.c (ppc_linux_vsx_regset_sections) New structure.
> 	(ppc_linux_vmx_regset_sections): New structure.
> 	(ppc_linux_fp_regset_sections): New structure.
> 	(ppc_linux_init_abi): Select core-file regset  based on target
> 	features.

This is OK.

Thanks,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

On Mon, 2008-08-25 at 20:26 +0200, Ulrich Weigand wrote:
> Luis Machado wrote:
> 
> > 	* ppc-linux-tdep.c (ppc_linux_vsx_regset_sections) New structure.
> > 	(ppc_linux_vmx_regset_sections): New structure.
> > 	(ppc_linux_fp_regset_sections): New structure.
> > 	(ppc_linux_init_abi): Select core-file regset  based on target
> > 	features.
> 
> This is OK.
> 
> Thanks,
> Ulrich

I've checked this in now.

Thanks,
Luis

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Ulrich Weigand]

Luis Machado wrote:

> 2008-07-25  Luis Machado  <luisgpm@br.ibm.com>
> 
> 	* ppc-linux-tdep.c (ppc_linux_regset_sections): Add new ".reg-ppc-vsx" field.
> 	(ppc32_linux_vsxregset): New 32-bit VSX-enabled regset.
> 	(ppc_linux_regset_from_core_section): Handle VSX core section.
> 	(ppc_linux_core_read_description): Support VSX-enabled core files.
> 
> 	* corelow.c (get_core_register_section): Support VSX-enabled 
> 	core files.

This is OK.

> Index: gdb/corelow.c
> ===================================================================
> --- gdb.orig/corelow.c	2008-07-23 09:28:09.000000000 -0700
> +++ gdb/corelow.c	2008-07-23 09:31:44.000000000 -0700
> @@ -499,6 +499,8 @@
>  			     ".reg-xfp", 3, "extended floating-point", 0);
>    get_core_register_section (regcache,
>    			     ".reg-ppc-vmx", 3, "ppc Altivec", 0);
> +  get_core_register_section (regcache,
> +			     ".reg-ppc-vsx", 4, "POWER7 VSX", 0);

It would be nice if we could convert this to a loop using the
gdbarch_core_regset_sections list at some point ...

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

On Thu, 2008-08-14 at 21:51 +0200, Ulrich Weigand wrote:

> > Index: gdb/corelow.c
> > ===================================================================
> > --- gdb.orig/corelow.c	2008-07-23 09:28:09.000000000 -0700
> > +++ gdb/corelow.c	2008-07-23 09:31:44.000000000 -0700
> > @@ -499,6 +499,8 @@
> >  			     ".reg-xfp", 3, "extended floating-point", 0);
> >    get_core_register_section (regcache,
> >    			     ".reg-ppc-vmx", 3, "ppc Altivec", 0);
> > +  get_core_register_section (regcache,
> > +			     ".reg-ppc-vsx", 4, "POWER7 VSX", 0);
> 
> It would be nice if we could convert this to a loop using the
> gdbarch_core_regset_sections list at some point ...

Agreed. I'll write a separate patch to cover this change.

Thanks,
Luis

Re: [PATCH-ppc 2/5] Add VSX support for core-files

[Luis Machado]

On Thu, 2008-08-14 at 21:51 +0200, Ulrich Weigand wrote:
> Luis Machado wrote:
> 
> > 2008-07-25  Luis Machado  <luisgpm@br.ibm.com>
> > 
> > 	* ppc-linux-tdep.c (ppc_linux_regset_sections): Add new ".reg-ppc-vsx" field.
> > 	(ppc32_linux_vsxregset): New 32-bit VSX-enabled regset.
> > 	(ppc_linux_regset_from_core_section): Handle VSX core section.
> > 	(ppc_linux_core_read_description): Support VSX-enabled core files.
> > 
> > 	* corelow.c (get_core_register_section): Support VSX-enabled 
> > 	core files.
> 
> This is OK.
> 
> > Index: gdb/corelow.c
> > ===================================================================
> > --- gdb.orig/corelow.c	2008-07-23 09:28:09.000000000 -0700
> > +++ gdb/corelow.c	2008-07-23 09:31:44.000000000 -0700
> > @@ -499,6 +499,8 @@
> >  			     ".reg-xfp", 3, "extended floating-point", 0);
> >    get_core_register_section (regcache,
> >    			     ".reg-ppc-vmx", 3, "ppc Altivec", 0);
> > +  get_core_register_section (regcache,
> > +			     ".reg-ppc-vsx", 4, "POWER7 VSX", 0);
> 
> It would be nice if we could convert this to a loop using the
> gdbarch_core_regset_sections list at some point ...
> 
> Bye,
> Ulrich

Checked in.

Luis