[PATCH 3/5] Use pseudosections for NT_FREEBSD_X86_SEGBASES core dump notes.

[John Baldwin <jhb@FreeBSD.org>]

This includes adding pseudosections when reading a core dump as well
as support for writing out a core dump note from a pseudosection.

bfd/ChangeLog:

	* elf-bfd.h (elfcore_write_x86_segbases): New.
	* elf.c (elfcore_grok_freebsd_note): Add pseudosections for
	NT_FREEBSD_X86_SEGBASES register notes.
	(elfcore_write_x86_segbases): New.
	(elfcore_write_register_note): Write NT_FREEBSD_X86_SEGBASES
	register notes.
---
 bfd/ChangeLog |  9 +++++++++
 bfd/elf-bfd.h |  2 ++
 bfd/elf.c     | 14 ++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index d1a31efe59c..9085d3a7664 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,12 @@
+2022-03-23  John Baldwin  <jhb@FreeBSD.org>
+
+	* elf-bfd.h (elfcore_write_x86_segbases): New.
+	* elf.c (elfcore_grok_freebsd_note): Add pseudosections for
+	NT_FREEBSD_X86_SEGBASES register notes.
+	(elfcore_write_x86_segbases): New.
+	(elfcore_write_register_note): Write NT_FREEBSD_X86_SEGBASES
+	register notes.
+
 2022-03-23  John Baldwin  <jhb@FreeBSD.org>
 
 	* elf.c (elfcore_grok_freebsd_note): Remove checks for namesz.
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index 5c3985f6e57..c7c0a793b15 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -2786,6 +2786,8 @@ extern char *elfcore_write_prxfpreg
   (bfd *, char *, int *, const void *, int);
 extern char *elfcore_write_xstatereg
   (bfd *, char *, int *, const void *, int);
+extern char *elfcore_write_x86_segbases
+  (bfd *, char *, int *, const void *, int);
 extern char *elfcore_write_ppc_vmx
   (bfd *, char *, int *, const void *, int);
 extern char *elfcore_write_ppc_vsx
diff --git a/bfd/elf.c b/bfd/elf.c
index a99149e50b3..37c53cfdf32 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -11027,6 +11027,9 @@ elfcore_grok_freebsd_note (bfd *abfd, Elf_Internal_Note *note)
     case NT_FREEBSD_PROCSTAT_AUXV:
       return elfcore_make_auxv_note_section (abfd, note, 4);
 
+    case NT_FREEBSD_X86_SEGBASES:
+      return elfcore_make_note_pseudosection (abfd, ".reg-x86-segbases", note);
+
     case NT_X86_XSTATE:
       return elfcore_grok_xstatereg (abfd, note);
 
@@ -11904,6 +11907,15 @@ elfcore_write_xstatereg (bfd *abfd, char *buf, int *bufsiz,
 			     note_name, NT_X86_XSTATE, xfpregs, size);
 }
 
+char *
+elfcore_write_x86_segbases (bfd *abfd, char *buf, int *bufsiz,
+			    const void *regs, int size)
+{
+  char *note_name = "FreeBSD";
+  return elfcore_write_note (abfd, buf, bufsiz,
+			     note_name, NT_FREEBSD_X86_SEGBASES, regs, size);
+}
+
 char *
 elfcore_write_ppc_vmx (bfd *abfd,
 		       char *buf,
@@ -12441,6 +12453,8 @@ elfcore_write_register_note (bfd *abfd,
     return elfcore_write_prxfpreg (abfd, buf, bufsiz, data, size);
   if (strcmp (section, ".reg-xstate") == 0)
     return elfcore_write_xstatereg (abfd, buf, bufsiz, data, size);
+  if (strcmp (section, ".reg-x86-segbases") == 0)
+    return elfcore_write_x86_segbases (abfd, buf, bufsiz, data, size);
   if (strcmp (section, ".reg-ppc-vmx") == 0)
     return elfcore_write_ppc_vmx (abfd, buf, bufsiz, data, size);
   if (strcmp (section, ".reg-ppc-vsx") == 0)
-- 
2.34.1