From FEDORA_PATCHES Mon Sep 17 00:00:00 2001

From: Alan Hayward <alan.hayward@arm.com>

Date: Wed, 7 Jul 2021 18:13:44 -0400

Subject: gdb-rhbz1854784-powerpc-remove-region-limit-dawr-2of7.patch

;; Backport "Add linux_get_hwcap"

;; (Alan Hayward, RH BZ 1854784)

Tidy up calls to read HWCAP (and HWCAP2) by adding common functions,

removing the PPC and AArch64 specific versions.

The only function difference is in aarch64_linux_core_read_description - if

the hwcap read fails it now return a valid description instead of nullptr.

gdb/ChangeLog:

2019-03-25  Alan Hayward  <alan.hayward@arm.com>

	* aarch64-linux-nat.c (aarch64_linux_nat_target::read_description):

	Call linux_get_hwcap.

	* aarch64-linux-tdep.c (aarch64_linux_core_read_description):

	Likewise.

	(aarch64_linux_get_hwcap): Remove function.

	* aarch64-linux-tdep.h (aarch64_linux_get_hwcap): Remove

	declaration.

	* arm-linux-nat.c (arm_linux_nat_target::read_description):Call

	linux_get_hwcap.

	* arm-linux-tdep.c (arm_linux_core_read_description): Likewise.

	* linux-tdep.c (linux_get_hwcap): Add function.

	(linux_get_hwcap2): Likewise.

	* linux-tdep.h (linux_get_hwcap): Add declaration.

	(linux_get_hwcap2): Likewise.

	* ppc-linux-nat.c (ppc_linux_get_hwcap): Remove function.

	(ppc_linux_get_hwcap2): Likewise.

	(ppc_linux_nat_target::region_ok_for_hw_watchpoint): Call

	linux_get_hwcap.

	(ppc_linux_nat_target::insert_watchpoint): Likewise.

	(ppc_linux_nat_target::watchpoint_addr_within_range): Likewise.

	(ppc_linux_nat_target::read_description): Likewise.

	* ppc-linux-tdep.c (ppc_linux_core_read_description): Likewise.

	* s390-linux-nat.c: Likewise.

	* s390-linux-tdep.c (s390_core_read_description): Likewise.

diff --git a/gdb/aarch64-linux-nat.c b/gdb/aarch64-linux-nat.c

--- a/gdb/aarch64-linux-nat.c

+++ b/gdb/aarch64-linux-nat.c

@@ -42,6 +42,7 @@

 #include <asm/ptrace.h>

 #include "gregset.h"

+#include "linux-tdep.h"

 /* Defines ps_err_e, struct ps_prochandle.  */

 #include "gdb_proc_service.h"

@@ -605,8 +606,7 @@ aarch64_linux_nat_target::read_description ()

   ret = ptrace (PTRACE_GETREGSET, tid, NT_ARM_VFP, &iovec);

   if (ret == 0)

     return tdesc_arm_with_neon;

-  else

-    return aarch64_read_description (aarch64_sve_get_vq (tid));

+  else return aarch64_read_description (aarch64_sve_get_vq (tid));

 }

 /* Convert a native/host siginfo object, into/from the siginfo in the

diff --git a/gdb/aarch64-linux-tdep.c b/gdb/aarch64-linux-tdep.c

--- a/gdb/aarch64-linux-tdep.c

+++ b/gdb/aarch64-linux-tdep.c

@@ -442,10 +442,7 @@ static const struct target_desc *

 aarch64_linux_core_read_description (struct gdbarch *gdbarch,

 				     struct target_ops *target, bfd *abfd)

 {

-  CORE_ADDR aarch64_hwcap = 0;

-

-  if (target_auxv_search (target, AT_HWCAP, &aarch64_hwcap) != 1)

-    return NULL;

+  CORE_ADDR hwcap = linux_get_hwcap (target);

   return aarch64_read_description (aarch64_linux_core_read_vq (gdbarch, abfd));

 }

diff --git a/gdb/arm-linux-nat.c b/gdb/arm-linux-nat.c

--- a/gdb/arm-linux-nat.c

+++ b/gdb/arm-linux-nat.c

@@ -533,7 +533,7 @@ ps_get_thread_area (struct ps_prochandle *ph,

 const struct target_desc *

 arm_linux_nat_target::read_description ()

 {

-  CORE_ADDR arm_hwcap = 0;

+  CORE_ADDR arm_hwcap = linux_get_hwcap (this);

   if (have_ptrace_getregset == TRIBOOL_UNKNOWN)

     {

@@ -551,11 +551,6 @@ arm_linux_nat_target::read_description ()

 	have_ptrace_getregset = TRIBOOL_TRUE;

     }

-  if (target_auxv_search (this, AT_HWCAP, &arm_hwcap) != 1)

-    {

-      return this->beneath ()->read_description ();

-    }

-

   if (arm_hwcap & HWCAP_IWMMXT)

     return tdesc_arm_with_iwmmxt;

diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c

--- a/gdb/arm-linux-tdep.c

+++ b/gdb/arm-linux-tdep.c

@@ -730,10 +730,7 @@ arm_linux_core_read_description (struct gdbarch *gdbarch,

                                  struct target_ops *target,

                                  bfd *abfd)

 {

-  CORE_ADDR arm_hwcap = 0;

-

-  if (target_auxv_search (target, AT_HWCAP, &arm_hwcap) != 1)

-    return NULL;

+  CORE_ADDR arm_hwcap = linux_get_hwcap (target);

   if (arm_hwcap & HWCAP_VFP)

     {

diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c

--- a/gdb/linux-tdep.c

+++ b/gdb/linux-tdep.c

@@ -2567,6 +2567,28 @@ linux_displaced_step_location (struct gdbarch *gdbarch)

   return addr;

 }

+/* See linux-tdep.h.  */

+

+CORE_ADDR

+linux_get_hwcap (struct target_ops *target)

+{

+  CORE_ADDR field;

+  if (target_auxv_search (target, AT_HWCAP, &field) != 1)

+    return 0;

+  return field;

+}

+

+/* See linux-tdep.h.  */

+

+CORE_ADDR

+linux_get_hwcap2 (struct target_ops *target)

+{

+  CORE_ADDR field;

+  if (target_auxv_search (target, AT_HWCAP2, &field) != 1)

+    return 0;

+  return field;

+}

+

 /* Display whether the gcore command is using the

    /proc/PID/coredump_filter file.  */

diff --git a/gdb/linux-tdep.h b/gdb/linux-tdep.h

--- a/gdb/linux-tdep.h

+++ b/gdb/linux-tdep.h

@@ -61,4 +61,12 @@ extern void linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch);

 extern int linux_is_uclinux (void);

+/* Fetch the AT_HWCAP entry from the auxv vector for the given TARGET.  On

+   error, 0 is returned.  */

+extern CORE_ADDR linux_get_hwcap (struct target_ops *target);

+

+/* Fetch the AT_HWCAP2 entry from the auxv vector for the given TARGET.  On

+   error, 0 is returned.  */

+extern CORE_ADDR linux_get_hwcap2 (struct target_ops *target);

+

 #endif /* linux-tdep.h */

diff --git a/gdb/ppc-linux-nat.c b/gdb/ppc-linux-nat.c

--- a/gdb/ppc-linux-nat.c

+++ b/gdb/ppc-linux-nat.c

@@ -50,6 +50,7 @@

 #include "arch/ppc-linux-common.h"

 #include "arch/ppc-linux-tdesc.h"

 #include "nat/ppc-linux.h"

+#include "linux-tdep.h"

 /* Similarly for the hardware watchpoint support.  These requests are used

    when the PowerPC HWDEBUG ptrace interface is not available.  */

@@ -1560,31 +1561,6 @@ store_ppc_registers (const struct regcache *regcache, int tid)

      function to fail most of the time, so we ignore them.  */

 }

-/* Fetch the AT_HWCAP entry from the aux vector.  */

-static CORE_ADDR

-ppc_linux_get_hwcap (void)

-{

-  CORE_ADDR field;

-

-  if (target_auxv_search (current_top_target (), AT_HWCAP, &field) != 1)

-    return 0;

-

-  return field;

-}

-

-/* Fetch the AT_HWCAP2 entry from the aux vector.  */

-

-static CORE_ADDR

-ppc_linux_get_hwcap2 (void)

-{

-  CORE_ADDR field;

-

-  if (target_auxv_search (current_top_target (), AT_HWCAP2, &field) != 1)

-    return 0;

-

-  return field;

-}

-

 /* The cached DABR value, to install in new threads.

    This variable is used when the PowerPC HWDEBUG ptrace

    interface is not available.  */

@@ -1741,7 +1717,7 @@ ppc_linux_nat_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, LONGEST len)

          takes two hardware watchpoints though.  */

       if (len > 1

 	  && hwdebug_info.features & PPC_DEBUG_FEATURE_DATA_BP_RANGE

-	  && ppc_linux_get_hwcap () & PPC_FEATURE_BOOKE)

+	  && linux_get_hwcap (current_top_target ()) & PPC_FEATURE_BOOKE)

 	return 2;

       /* Check if the processor provides DAWR interface.  */

       if (hwdebug_info.features & PPC_DEBUG_FEATURE_DATA_BP_DAWR)

@@ -1761,7 +1737,7 @@ ppc_linux_nat_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, LONGEST len)

      ptrace interface, DAC-based processors (i.e., embedded processors) will

      use addresses aligned to 4-bytes due to the way the read/write flags are

      passed in the old ptrace interface.  */

-  else if (((ppc_linux_get_hwcap () & PPC_FEATURE_BOOKE)

+  else if (((linux_get_hwcap (current_top_target ()) & PPC_FEATURE_BOOKE)

 	   && (addr + len) > (addr & ~3) + 4)

 	   || (addr + len) > (addr & ~7) + 8)

     return 0;

@@ -2303,7 +2279,7 @@ ppc_linux_nat_target::insert_watchpoint (CORE_ADDR addr, int len,

       long dabr_value;

       long read_mode, write_mode;

-      if (ppc_linux_get_hwcap () & PPC_FEATURE_BOOKE)

+      if (linux_get_hwcap (current_top_target ()) & PPC_FEATURE_BOOKE)

 	{

 	  /* PowerPC 440 requires only the read/write flags to be passed

 	     to the kernel.  */

@@ -2506,9 +2482,9 @@ ppc_linux_nat_target::watchpoint_addr_within_range (CORE_ADDR addr,

   int mask;

   if (have_ptrace_hwdebug_interface ()

-      && ppc_linux_get_hwcap () & PPC_FEATURE_BOOKE)

+      && linux_get_hwcap (current_top_target ()) & PPC_FEATURE_BOOKE)

     return start <= addr && start + length >= addr;

-  else if (ppc_linux_get_hwcap () & PPC_FEATURE_BOOKE)

+  else if (linux_get_hwcap (current_top_target ()) & PPC_FEATURE_BOOKE)

     mask = 3;

   else

     mask = 7;

@@ -2646,8 +2622,8 @@ ppc_linux_nat_target::read_description ()

   features.wordsize = ppc_linux_target_wordsize (tid);

-  CORE_ADDR hwcap = ppc_linux_get_hwcap ();

-  CORE_ADDR hwcap2 = ppc_linux_get_hwcap2 ();

+  CORE_ADDR hwcap = linux_get_hwcap (current_top_target ());

+  CORE_ADDR hwcap2 = linux_get_hwcap2 (current_top_target ());

   if (have_ptrace_getsetvsxregs

       && (hwcap & PPC_FEATURE_HAS_VSX))

diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c

--- a/gdb/ppc-linux-tdep.c

+++ b/gdb/ppc-linux-tdep.c

@@ -1602,10 +1602,7 @@ ppc_linux_core_read_description (struct gdbarch *gdbarch,

   if (vsx)

     features.vsx = true;

-  CORE_ADDR hwcap;

-

-  if (target_auxv_search (target, AT_HWCAP, &hwcap) != 1)

-    hwcap = 0;

+  CORE_ADDR hwcap = linux_get_hwcap (target);

   features.isa205 = ppc_linux_has_isa205 (hwcap);

diff --git a/gdb/s390-linux-nat.c b/gdb/s390-linux-nat.c

--- a/gdb/s390-linux-nat.c

+++ b/gdb/s390-linux-nat.c

@@ -42,6 +42,7 @@

 #include <elf.h>

 #include <algorithm>

 #include "inf-ptrace.h"

+#include "linux-tdep.h"

 /* Per-thread arch-specific data.  */

@@ -1018,9 +1019,8 @@ s390_linux_nat_target::read_description ()

      that mode, report s390 architecture with 64-bit GPRs.  */

 #ifdef __s390x__

   {

-    CORE_ADDR hwcap = 0;

+    CORE_ADDR hwcap = linux_get_hwcap (current_top_target ());

-    target_auxv_search (current_top_target (), AT_HWCAP, &hwcap);

     have_regset_tdb = (hwcap & HWCAP_S390_TE)

       && check_regset (tid, NT_S390_TDB, s390_sizeof_tdbregset);

diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c

--- a/gdb/s390-linux-tdep.c

+++ b/gdb/s390-linux-tdep.c

@@ -332,10 +332,9 @@ s390_core_read_description (struct gdbarch *gdbarch,

 			    struct target_ops *target, bfd *abfd)

 {

   asection *section = bfd_get_section_by_name (abfd, ".reg");

-  CORE_ADDR hwcap = 0;

+  CORE_ADDR hwcap = linux_get_hwcap (target);

   bool high_gprs, v1, v2, te, vx, gs;

-  target_auxv_search (target, AT_HWCAP, &hwcap);

   if (!section)

     return NULL;