Support TLS variables on FreeBSD/powerpc.

Derive the pointer to the DTV array from the %r2 register on 32-bit
powerpc and %r13 on 64-bit powerpc.

gdb/ChangeLog:

	* ppc-fbsd-tdep.c (ppcfbsd_get_thread_local_address): New.
	(ppcfbsd_init_abi): Install gdbarch
	"fetch_tls_load_module_address" and "get_thread_local_address"
	methods.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 741799d8b3ea155cc0a1c001814b0f293f2bd0a7..fe7504c27a7fa639bd9bb106d924563f4a30a457 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2019-03-12  John Baldwin  <jhb@FreeBSD.org>
+
+       * ppc-fbsd-tdep.c (ppcfbsd_get_thread_local_address): New.
+       (ppcfbsd_init_abi): Install gdbarch
+       "fetch_tls_load_module_address" and "get_thread_local_address"
+       methods.
+
 2019-03-12  John Baldwin  <jhb@FreeBSD.org>
 
        * riscv-fbsd-tdep.c (riscv_fbsd_get_thread_local_address): New.

diff --git a/gdb/ppc-fbsd-tdep.c b/gdb/ppc-fbsd-tdep.c
index c21a52c89837a6e61591d8ca5c2de96c94cfc561..290bd1fd88281c79fce3b7ac965942b5acd99aec 100644 (file)
--- a/gdb/ppc-fbsd-tdep.c
+++ b/gdb/ppc-fbsd-tdep.c
@@ -279,6 +279,39 @@ ppcfbsd_return_value (struct gdbarch *gdbarch, struct value *function,
                                           regcache, readbuf, writebuf);
 }
 
+/* Implement the "get_thread_local_address" gdbarch method.  */
+
+static CORE_ADDR
+ppcfbsd_get_thread_local_address (struct gdbarch *gdbarch, ptid_t ptid,
+                                 CORE_ADDR lm_addr, CORE_ADDR offset)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+  struct regcache *regcache;
+  int tp_offset, tp_regnum;
+
+  regcache = get_thread_arch_regcache (ptid, gdbarch);
+
+  if (tdep->wordsize == 4)
+    {
+      tp_offset = 0x7008;
+      tp_regnum = PPC_R0_REGNUM + 2;
+    }
+  else
+    {
+      tp_offset = 0x7010;
+      tp_regnum = PPC_R0_REGNUM + 13;
+    }
+  target_fetch_registers (regcache, tp_regnum);
+
+  ULONGEST tp;
+  if (regcache->cooked_read (tp_regnum, &tp) != REG_VALID)
+    error (_("Unable to fetch tcb pointer"));
+
+  /* tp points to the end of the TCB block.  The first member of the
+     TCB is the pointer to the DTV array.  */
+  CORE_ADDR dtv_addr = tp - tp_offset;
+  return fbsd_get_thread_local_address (gdbarch, dtv_addr, lm_addr, offset);
+}
 
 static void
 ppcfbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
@@ -322,6 +355,8 @@ ppcfbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 
   set_gdbarch_fetch_tls_load_module_address (gdbarch,
                                             svr4_fetch_objfile_link_map);
+  set_gdbarch_get_thread_local_address (gdbarch,
+                                       ppcfbsd_get_thread_local_address);
 }
 
 void