[v2] Cache the Thread Local Base pointer type in the gdbarch

Message ID 20200211163138.2810-1-ssbssa@yahoo.de
State New, archived
Headers

Commit Message

Terekhov, Mikhail via Gdb-patches Feb. 11, 2020, 4:31 p.m. UTC
  gdb/ChangeLog:

2020-02-11  Hannes Domani  <ssbssa@yahoo.de>

	* windows-tdep.c (struct windows_gdbarch_data): Add tib_ptr_type.
	(windows_get_tlb_type): Use windows_gdbarch_data->tib_ptr_type.
---
 gdb/windows-tdep.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)
  

Comments

Simon Marchi Feb. 12, 2020, 4:06 a.m. UTC | #1
On 2020-02-11 11:31 a.m., Hannes Domani via gdb-patches wrote:
> @@ -196,10 +196,10 @@ windows_get_tlb_type (struct gdbarch *gdbarch)
>    struct type *word_type, *wchar_type, *wchar_ptr_type;
>    struct type *uni_str_type, *rupp_type, *rupp_ptr_type;
>  
> -  /* Do not rebuild type if same gdbarch as last time.  */
> -  if (last_tlb_type && last_gdbarch == gdbarch)
> -    return last_tlb_type;
> -  
> +  windows_gdbarch_data = get_windows_gdbarch_data (gdbarch);

You can declare the variable in place:

  windows_gdbarch_data *windows_gdbarch_data
    = get_windows_gdbarch_data (gdbarch);

That code style rule changed when we switched to C++, this is why you can still see
a lot of code declaring variables at the top of the functions.

The patch LGTM with that fixed (if you want, it's really a detail).  Thanks for doing
this, it's a nice cleanup.

Simon
  
Terekhov, Mikhail via Gdb-patches Feb. 12, 2020, 4:06 p.m. UTC | #2
Am Mittwoch, 12. Februar 2020, 05:06:33 MEZ hat Simon Marchi <simark@simark.ca> Folgendes geschrieben:

> On 2020-02-11 11:31 a.m., Hannes Domani via gdb-patches wrote:
> > @@ -196,10 +196,10 @@ windows_get_tlb_type (struct gdbarch *gdbarch)
> >    struct type *word_type, *wchar_type, *wchar_ptr_type;
> >    struct type *uni_str_type, *rupp_type, *rupp_ptr_type;
> >
> > -  /* Do not rebuild type if same gdbarch as last time.  */
> > -  if (last_tlb_type && last_gdbarch == gdbarch)
> > -    return last_tlb_type;
> > -
> > +  windows_gdbarch_data = get_windows_gdbarch_data (gdbarch);
>
> You can declare the variable in place:
>
>   windows_gdbarch_data *windows_gdbarch_data
>     = get_windows_gdbarch_data (gdbarch);
>
>
> That code style rule changed when we switched to C++, this is why you can still see
> a lot of code declaring variables at the top of the functions.
>
> The patch LGTM with that fixed (if you want, it's really a detail).  Thanks for doing
> this, it's a nice cleanup.

Pushed with this change, thanks.
  

Patch

diff --git a/gdb/windows-tdep.c b/gdb/windows-tdep.c
index 6eef476fb5..f3c6785218 100644
--- a/gdb/windows-tdep.c
+++ b/gdb/windows-tdep.c
@@ -162,6 +162,7 @@  static struct gdbarch_data *windows_gdbarch_data_handle;
 struct windows_gdbarch_data
 {
   struct type *siginfo_type;
+  struct type *tib_ptr_type; /* Type of thread information block */
 };
 
 /* Allocate windows_gdbarch_data for an arch.  */
@@ -186,8 +187,7 @@  get_windows_gdbarch_data (struct gdbarch *gdbarch)
 static struct type *
 windows_get_tlb_type (struct gdbarch *gdbarch)
 {
-  static struct gdbarch *last_gdbarch = NULL;
-  static struct type *last_tlb_type = NULL;
+  struct windows_gdbarch_data *windows_gdbarch_data;
   struct type *dword_ptr_type, *dword32_type, *void_ptr_type;
   struct type *peb_ldr_type, *peb_ldr_ptr_type;
   struct type *peb_type, *peb_ptr_type, *list_type;
@@ -196,10 +196,10 @@  windows_get_tlb_type (struct gdbarch *gdbarch)
   struct type *word_type, *wchar_type, *wchar_ptr_type;
   struct type *uni_str_type, *rupp_type, *rupp_ptr_type;
 
-  /* Do not rebuild type if same gdbarch as last time.  */
-  if (last_tlb_type && last_gdbarch == gdbarch)
-    return last_tlb_type;
-  
+  windows_gdbarch_data = get_windows_gdbarch_data (gdbarch);
+  if (windows_gdbarch_data->tib_ptr_type != nullptr)
+    return windows_gdbarch_data->tib_ptr_type;
+
   dword_ptr_type = arch_integer_type (gdbarch, gdbarch_ptr_bit (gdbarch),
 				 1, "DWORD_PTR");
   dword32_type = arch_integer_type (gdbarch, 32,
@@ -369,8 +369,7 @@  windows_get_tlb_type (struct gdbarch *gdbarch)
 			    NULL);
   TYPE_TARGET_TYPE (tib_ptr_type) = tib_type;
 
-  last_tlb_type = tib_ptr_type;
-  last_gdbarch = gdbarch;
+  windows_gdbarch_data->tib_ptr_type = tib_ptr_type;
 
   return tib_ptr_type;
 }