[7.5] PATCH: PR backtrace/14646 [x32] backtrace doesn't work

["H.J. Lu" <hjl.tools@gmail.com>]

Hi,

This patch backports the fix from trunk to 7.5 branch.  Tested on
Linux/x86-64 and Linux/x32.  OK to install?

Thanks.


H.J.
----
	PR backtrace/14646
	PR gdb/14647
	* i386-tdep.h (gdbarch_tdep): Remove sp_regnum_from_eax and
	pc_regnum_from_eax.
	* i386-tdep.c (i386_gdbarch_init): Don't use sp_regnum_from_eax
	nor pc_regnum_from_eax.
	* amd64-tdep.c (amd64_x32_init_abi): Don't set sp_regnum_from_eax
	nor pc_regnum_from_eax.

diff --git a/gdb/amd64-tdep.c b/gdb/amd64-tdep.c
index 5424926..8ae1142 100644
--- a/gdb/amd64-tdep.c
+++ b/gdb/amd64-tdep.c
@@ -2946,9 +2946,6 @@ amd64_x32_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
     tdesc = tdesc_x32;
   tdep->tdesc = tdesc;
 
-  tdep->sp_regnum_from_eax = AMD64_RSP_REGNUM;
-  tdep->pc_regnum_from_eax = AMD64_RIP_REGNUM;
-
   tdep->num_dword_regs = 17;
   set_tdesc_pseudo_register_type (gdbarch, amd64_x32_pseudo_register_type);
 
diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
index 84e9794..ddb20aa 100644
--- a/gdb/i386-tdep.c
+++ b/gdb/i386-tdep.c
@@ -7705,9 +7705,6 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   tdep->num_mmx_regs = 8;
   tdep->num_ymm_regs = 0;
 
-  tdep->sp_regnum_from_eax = -1;
-  tdep->pc_regnum_from_eax = -1;
-
   tdesc_data = tdesc_data_alloc ();
 
   set_gdbarch_relocate_instruction (gdbarch, i386_relocate_instruction);
@@ -7752,14 +7749,6 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
       /* Support dword pseudo-register if it hasn't been disabled.  */
       tdep->eax_regnum = ymm0_regnum;
       ymm0_regnum += tdep->num_dword_regs;
-      if (tdep->sp_regnum_from_eax != -1)
-	set_gdbarch_sp_regnum (gdbarch,
-			       (tdep->eax_regnum
-				+ tdep->sp_regnum_from_eax));
-      if (tdep->pc_regnum_from_eax != -1)
-	set_gdbarch_pc_regnum (gdbarch,
-			       (tdep->eax_regnum
-				+ tdep->pc_regnum_from_eax));
     }
   else
     tdep->eax_regnum = -1;
diff --git a/gdb/i386-tdep.h b/gdb/i386-tdep.h
index 76afdce..5f233f5 100644
--- a/gdb/i386-tdep.h
+++ b/gdb/i386-tdep.h
@@ -149,14 +149,6 @@ struct gdbarch_tdep
      of pseudo dword register support.  */
   int eax_regnum;
 
-  /* Register number for SP, relative to %eax.  Set this to -1 to
-     indicate the absence of pseudo SP register support.  */
-  int sp_regnum_from_eax;
-
-  /* Register number for PC, relative to %eax.  Set this to -1 to
-     indicate the absence of pseudo PC register support.  */
-  int pc_regnum_from_eax;
-
   /* Number of core registers.  */
   int num_core_regs;