Refactor sigcontextinfo.h

This patch refactor sigcontextinfo.h header to use SA_SIGINFO as default
for both gmon and debug implementations.  This allows simplify
profil-counter.h on Linux to use a single implementation and remove the
requirements for newer ports to redefine __sigaction/sigaction to use
SA_SIGINFO.

The GET_PC macro is also replaced with a function sigcontext_get_pc that
returns an uintptr_t instead of a void pointer.  It allows easier convertion
to integer on ILP32 architecture, such as x32, without the need to suppress
compiler warnings.

The patch also requires some refactor of register-dump.h file for some
architectures (to reflect it is now called from a sa_sigaction instead of
sa_handler signal context).

   - Alpha, i386, and s390 are straighfoward to take in consideration the
     new argument type.

   - ia64 takes in consideration the kernel pass a struct sigcontextt
     as third argument for sa_sigaction.

   - sparc take in consideration the kernel pass a pt_regs struct
     as third argument for sa_sigaction.

   - m68k dummy function is removed and the FP state is dumped on
     register_dump itself.

   - For SH the register-dump.h file is consolidate on a common implementation
     and the floating-point state is checked based on ownedfp field.

The register_dump does not change its output format in any affected
architecture.

I checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
arm-linux-gnueabihf, sparcv9-linux-gnu, sparc64-linux-gnu, powerpc-linux-gnu,
powerpc64-linux-gnu, and powerpc64le-linux-gnu.

I also checked the libSegFault.so through catchsegv on alpha-linux-gnu,
m68k-linux-gnu and sh4-linux-gnu to confirm the output has not changed.

	Adhemerval Zanella  <adhemerval.zanella@linaro.org>
	Florian Weimer  <fweimer@redhat.com>

	* debug/segfault.c (install_handler): Use SA_SIGINFO if defined.
	* sysdeps/generic/profil-counter.h (__profil_counter): Cast to
	uintptr_t.
	* sysdeps/generic/sigcontextinfo.h (GET_PC): Rename to
	sigcontext_get_pc and return aligned cast to uintptr_t.
	* sysdeps/mach/hurd/i386/sigcontextinfo.h (GET_PC): Likewise.
	* sysdeps/posix/profil.c (profil_count): Change PC argument to
	uintptr_t.
	(__profil): Use SA_SIGINFO.
	* sysdeps/posix/sprofil.c (profil_count): Change PCP argument to
	uintptr_t.
	(__sprofil): Use SA_SIGINFO.
	* sysdeps/unix/sysv/linux/profil-counter.h: New file.
	* sysdeps/unix/sysv/linux/aarch64/profil-counter.h: Remove file.
	* sysdeps/unix/sysv/linux/csky/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/hppa/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/ia64/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/nios2/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/riscv/profil-counter.h: Likewise.
	* sysdeps/sysv/linux/s390/s390-32/profil-counter.h: Likewise.
	* sysdeps/sysv/linux/s390/s390-64/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/profil-counter.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/profil-counter.h (__profil_counter):
	Assume SA_SIGINFO and use sigcontext_get_pc instead of GET_PC.
	* sysdeps/unix/sysv/linux/sparc/profil-counter.h: New file.
	* sysdeps/unix/sysv/linux/sparc/sparc64/profil-counter.h: Remove file.
	* sysdeps/unix/sysv/linux/sparc/sparc32/profil-counter.h: Likewise.
	* sysdpes/unix/sysv/linux/aarch64/sigcontextinfo.h (SIGCONTEXT,
	GET_PC, __sigaction, sigaction): Remove defines.
	(sigcontext_get_pc): New function.
	* sysdeps/unix/sysv/linux/alpha/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/csky/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/hppa/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/m68k/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/nios2/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/riscv/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/sigcontextinfo.h: Likewise.
	* sysdeps/sysv/linux/sparc/sparc32/sigcontextinfo.h: Likewise.
	* sysdeps/sysv/linux/sparc/sparc64/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sigcontextinfo.h: Likewise.
	* sysdeps/unix/sysv/linux/alpha/register-dump.h (register_dump):
	Handle CTX argument as ucontext_t.
	* sysdeps/unix/sysv/linux/i386/register-dump.h: Likewise.
	Likewise.
	* sysdeps/unix/sysv/linux/m68k/register-dump.h: Likewise.
	* sysdeps/sysv/linux/s390/s390-32/register-dump.h: Likewise.
	* sysdeps/sysv/linux/s390/s390-64/register-dump.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/register-dump.h: New file.
	* sysdeps/unix/sysv/linux/sh/sh4/register-dump.h: Remove File.
	* sysdeps/unix/sysv/linux/sh/sh3/register-dump.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/register-dump.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/register-dump.h: Likewise.
	* sysdeps/unix/sysv/linux/Makefile (tests-internal): Add
	tst-sigcontextinfo-get_pc.
	* sysdeps/unix/sysv/linux/tst-sigcontextinfo-get_pc.c: New file.
	(CFLAGS-tst-sigcontextinfo-get_pc.c): New rule.

3 files changed, 70 insertions, 42 deletions

diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/profil-counter.h b/sysdeps/unix/sysv/linux/sparc/sparc64/profil-counter.h
deleted file mode 100644
index 47f8bf94a1..0000000000
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/profil-counter.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/* Low-level statistical profiling support function.  Linux/Sparc64 version.
-   Copyright (C) 1997-2019 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <signal.h>
-
-void
-__profil_counter (int signo, struct sigcontext *si)
-{
-  profil_count ((void *) si->sigc_regs.tpc);
-}
-#ifndef __profil_counter
-weak_alias (__profil_counter, profil_counter)
-#endif
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/register-dump.h b/sysdeps/unix/sysv/linux/sparc/sparc64/register-dump.h
index 0f1078ad9e..23ff36453a 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/register-dump.h
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/register-dump.h
@@ -60,17 +60,36 @@ hexvalue (unsigned long int value, char *buf, size_t len)
     *--cp = '0';
 }
 
+/* The sparc64 kernel signal frame for SA_SIGINFO is defined as:
+
+   struct rt_signal_frame
+     {
+       struct sparc_stackf ss;
+       siginfo_t info;
+       struct pt_regs regs;          <- void *ctx
+       __siginfo_fpu_t *fpu_save;
+       stack_t stack;
+       sigset_t mask;
+       __siginfo_rwin_t *rwin_save;
+     };
+
+  Unlike other architectures, sparc32 passes pt_regs32 REGS pointers as
+  the third argument to a sa_sigaction handler with SA_SIGINFO enabled.  */
+
 static void
-register_dump (int fd, SIGCONTEXT ctx)
+register_dump (int fd, void *ctx)
 {
   char regs[36][16];
   char fregs[68][8];
   struct iovec iov[150];
   size_t nr = 0;
   int i;
-  unsigned long *r = (unsigned long *)
-    (ctx->sigc_regs.u_regs[14] + STACK_BIAS);
-  __siginfo_fpu_t *f;
+  struct pt_regs *ptregs = (struct pt_regs*) ((siginfo_t *)ctx + 1);
+  unsigned long *r = (unsigned long *) (ptregs->u_regs[14] + STACK_BIAS);
+  __siginfo_fpu_t *f = (__siginfo_fpu_t *)(ptregs + 1);
+  struct kernel_sigset_t {
+    unsigned long sig[1];
+  } *mask = (struct kernel_sigset_t *)((stack_t *)(f + 1) + 1);
 
 #define ADD_STRING(str) \
   iov[nr].iov_base = (char *) str;					      \
@@ -82,15 +101,15 @@ register_dump (int fd, SIGCONTEXT ctx)
   ++nr
 
   /* Generate strings of register contents.  */
-  hexvalue (ctx->sigc_regs.tstate,	regs[0], 16);
-  hexvalue (ctx->sigc_regs.tpc,		regs[1], 16);
-  hexvalue (ctx->sigc_regs.tnpc,	regs[2], 16);
-  hexvalue (ctx->sigc_regs.y,		regs[3], 8);
+  hexvalue (ptregs->tstate, regs[0], 16);
+  hexvalue (ptregs->tpc, regs[1], 16);
+  hexvalue (ptregs->tnpc, regs[2], 16);
+  hexvalue (ptregs->y, regs[3], 8);
   for (i = 1; i <= 15; i++)
-    hexvalue (ctx->sigc_regs.u_regs[i], regs[3+i], 16);
+    hexvalue (ptregs->u_regs[i], regs[3+i], 16);
   for (i = 0; i <= 15; i++)
-    hexvalue (r[i],			regs[19+i], 16);
-  hexvalue (ctx->sigc_mask,		regs[35], 16);
+    hexvalue (r[i], regs[19+i], 16);
+  hexvalue (mask->sig[0], regs[35], 16);
 
   /* Generate the output.  */
   ADD_STRING ("Register dump:\n\n TSTATE: ");
@@ -166,7 +185,6 @@ register_dump (int fd, SIGCONTEXT ctx)
   ADD_STRING ("\n\n Mask: ");
   ADD_MEM (regs[35], 16);
 
-  f = ctx->sigc_fpu_save;
   if (f != NULL)
     {
       for (i = 0; i < 64; i++)
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/sigcontextinfo.h b/sysdeps/unix/sysv/linux/sparc/sparc64/sigcontextinfo.h
index a2f2b1f7de..242b490fcc 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/sigcontextinfo.h
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/sigcontextinfo.h
@@ -16,8 +16,46 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifndef _SIGCONTEXTINFO_H
+#define _SIGCONTEXTINFO_H
+
+#include <bits/types/siginfo_t.h>
+
+/* The sparc64 kernel signal frame for SA_SIGINFO is defined as:
+
+   struct rt_signal_frame
+   {
+     struct sparc_stackf ss;
+     siginfo_t info;
+     struct pt_regs regs;
+     __siginfo_fpu_t *fpu_save;
+     stack_t stack;
+     sigset_t mask;
+     __siginfo_rwin_t *rwin_save;
+   };
+
+   Unlike other architectures, sparc64 passe the siginfo_t INFO pointer
+   as the third argument to a sa_sigaction handler with SA_SIGINFO enabled.  */
+
 #ifndef STACK_BIAS
 #define STACK_BIAS 2047
 #endif
-#define SIGCONTEXT struct sigcontext *
-#define GET_PC(__ctx)	((void *) ((__ctx)->sigc_regs.tpc))
+
+struct pt_regs
+{
+  unsigned long int u_regs[16];
+  unsigned long int tstate;
+  unsigned long int tpc;
+  unsigned long int tnpc;
+  unsigned int y;
+  unsigned int magic;
+};
+
+static inline uintptr_t
+sigcontext_get_pc (const siginfo_t *ctx)
+{
+  struct pt_regs *regs = (struct pt_regs*) ((siginfo_t *)(ctx) + 1);
+  return regs->tpc;
+}
+
+#endif