[PATCH] Fix arm-netbsd build error

[Christian Biesinger via gdb-patches]

The floating point register interface has changed to this:
https://github.com/NetBSD/src/blob/trunk/sys/arch/arm/include/reg.h

It now uses VFP instead of FPA registers. This patch updates
arm-nbsd-nat.c accordingly.

Tested by compiling on arm-netbsd on qemu. For actually testing, there
seems to be something missing as "info registers" only shows FPA
registers and no VFP ones. I am still investigating why this is;
please let me know if you know. However, I think this is still good
to check in as-is.

gdb/ChangeLog:

2020-02-11  Christian Biesinger  <cbiesinger@google.com>

	* arm-nbsd-nat.c (arm_supply_fparegset): Rename to...
	(arm_supply_vfpregset): ...this, and update to use VFP registers.
	(fetch_fp_register): Update.
	(fetch_fp_regs): Update.
	(store_fp_register): Update.
	(store_fp_regs): Update.
	(fetch_elfcore_registers): Update.
---
 gdb/arm-nbsd-nat.c | 80 ++++++++++++++++++++--------------------------
 1 file changed, 34 insertions(+), 46 deletions(-)

diff --git a/gdb/arm-nbsd-nat.c b/gdb/arm-nbsd-nat.c
index 11afc289c3..8027f54dfe 100644
--- a/gdb/arm-nbsd-nat.c
+++ b/gdb/arm-nbsd-nat.c
@@ -65,15 +65,13 @@ arm_supply_gregset (struct regcache *regcache, struct reg *gregset)
 }
 
 static void
-arm_supply_fparegset (struct regcache *regcache, struct fpreg *fparegset)
+arm_supply_vfpregset (struct regcache *regcache, struct fpreg *fpregset)
 {
-  int regno;
-
-  for (regno = ARM_F0_REGNUM; regno <= ARM_F7_REGNUM; regno++)
-    regcache->raw_supply (regno,
-			  (char *) &fparegset->fpr[regno - ARM_F0_REGNUM]);
+  struct vfpreg &vfp = fpregset->fpr_vfp;
+  for (int regno = ARM_D0_REGNUM; regno <= ARM_D31_REGNUM; regno++)
+    regcache->raw_supply (regno, (char *) &vfp.vfp_regs[regno - ARM_D0_REGNUM]);
 
-  regcache->raw_supply (ARM_FPS_REGNUM, (char *) &fparegset->fpr_fpsr);
+  regcache->raw_supply (ARM_FPSCR_REGNUM, (char *) &vfp.vfp_fpscr);
 }
 
 static void
@@ -147,10 +145,10 @@ static void
 fetch_fp_register (struct regcache *regcache, int regno)
 {
   struct fpreg inferior_fp_registers;
-  int ret;
+  int ret = ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
+		    (PTRACE_TYPE_ARG3) &inferior_fp_registers, 0);
 
-  ret = ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
-		(PTRACE_TYPE_ARG3) &inferior_fp_registers, 0);
+  struct vfpreg &vfp = inferior_fp_registers.fpr_vfp;
 
   if (ret < 0)
     {
@@ -158,18 +156,15 @@ fetch_fp_register (struct regcache *regcache, int regno)
       return;
     }
 
-  switch (regno)
+  if (regno == ARM_FPSCR_REGNUM)
+    regcache->raw_supply (ARM_FPSCR_REGNUM, (char *) &vfp.vfp_fpscr);
+  else if (regno >= ARM_D0_REGNUM && regno <= ARM_D31_REGNUM)
     {
-    case ARM_FPS_REGNUM:
-      regcache->raw_supply (ARM_FPS_REGNUM,
-			    (char *) &inferior_fp_registers.fpr_fpsr);
-      break;
-
-    default:
-      regcache->raw_supply
-	(regno, (char *) &inferior_fp_registers.fpr[regno - ARM_F0_REGNUM]);
-      break;
+      regcache->raw_supply (regno,
+			    (char *) &vfp.vfp_regs[regno - ARM_D0_REGNUM]);
     }
+  else
+    warning (_("Invalid register number."));
 }
 
 static void
@@ -188,7 +183,7 @@ fetch_fp_regs (struct regcache *regcache)
       return;
     }
 
-  arm_supply_fparegset (regcache, &inferior_fp_registers);
+  arm_supply_vfpregset (regcache, &inferior_fp_registers);
 }
 
 void
@@ -327,10 +322,9 @@ static void
 store_fp_register (const struct regcache *regcache, int regno)
 {
   struct fpreg inferior_fp_registers;
-  int ret;
-
-  ret = ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
-		(PTRACE_TYPE_ARG3) &inferior_fp_registers, 0);
+  int ret = ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
+		    (PTRACE_TYPE_ARG3) &inferior_fp_registers, 0);
+  struct vfpreg &vfp = inferior_fp_registers.fpr_vfp;
 
   if (ret < 0)
     {
@@ -338,18 +332,15 @@ store_fp_register (const struct regcache *regcache, int regno)
       return;
     }
 
-  switch (regno)
+  if (regno == ARM_FPSCR_REGNUM)
+    regcache->raw_collect (ARM_FPSCR_REGNUM, (char *) &vfp.vfp_fpscr);
+  else if (regno >= ARM_D0_REGNUM && regno <= ARM_D31_REGNUM)
     {
-    case ARM_FPS_REGNUM:
-      regcache->raw_collect (ARM_FPS_REGNUM,
-			     (char *) &inferior_fp_registers.fpr_fpsr);
-      break;
-
-    default:
-      regcache->raw_collect
-	(regno, (char *) &inferior_fp_registers.fpr[regno - ARM_F0_REGNUM]);
-      break;
+      regcache->raw_collect (regno,
+			     (char *) &vfp.vfp_regs[regno - ARM_D0_REGNUM]);
     }
+  else
+    warning (_("Invalid register number."));
 
   ret = ptrace (PT_SETFPREGS, regcache->ptid ().pid (),
 		(PTRACE_TYPE_ARG3) &inferior_fp_registers, 0);
@@ -361,20 +352,17 @@ store_fp_register (const struct regcache *regcache, int regno)
 static void
 store_fp_regs (const struct regcache *regcache)
 {
-  struct fpreg inferior_fp_registers;
-  int ret;
-  int regno;
+  struct fpreg fpregs;
 
-
-  for (regno = ARM_F0_REGNUM; regno <= ARM_F7_REGNUM; regno++)
+  for (int regno = ARM_D0_REGNUM; regno <= ARM_D31_REGNUM; regno++)
     regcache->raw_collect
-      (regno, (char *) &inferior_fp_registers.fpr[regno - ARM_F0_REGNUM]);
+      (regno, (char *) &fpregs.fpr_vfp.vfp_regs[regno - ARM_D0_REGNUM]);
 
-  regcache->raw_collect (ARM_FPS_REGNUM,
-			 (char *) &inferior_fp_registers.fpr_fpsr);
+  regcache->raw_collect (ARM_FPSCR_REGNUM,
+			 (char *) &fpregs.fpr_vfp.vfp_fpscr);
 
-  ret = ptrace (PT_SETFPREGS, regcache->ptid ().pid (),
-		(PTRACE_TYPE_ARG3) &inferior_fp_registers, 0);
+  int ret = ptrace (PT_SETFPREGS, regcache->ptid ().pid (),
+		    (PTRACE_TYPE_ARG3) &fpregs, 0);
 
   if (ret < 0)
     warning (_("unable to store floating-point registers"));
@@ -427,7 +415,7 @@ fetch_elfcore_registers (struct regcache *regcache,
 	  /* The memcpy may be unnecessary, but we can't really be sure
 	     of the alignment of the data in the core file.  */
 	  memcpy (&fparegset, core_reg_sect, sizeof (fparegset));
-	  arm_supply_fparegset (regcache, &fparegset);
+	  arm_supply_vfpregset (regcache, &fparegset);
 	}
       break;
 
-- 
2.25.0.225.g125e21ebc7-goog