[PATCH 1/8] [AArch64] Refactor aarch64_make_prologue_cache

[Pierre Langlois <pierre.langlois@arm.com>]

We would previously have to make sure the frame cache was not already
created before calling aarch64_make_prologue_cache.  This patch makes
this function check it so that the caller does not need to do so.

gdb/ChangeLog:

	* aarch64-tdep.c (aarch64_prologue_cache): New argument
	this_cache.  Return early if this_cache is already set.  Set
	this_cache.
	(aarch64_prologue_this_id): Update call to
	aarch64_prologue_cache.
	(aarch64_prologue_prev_register): Likewise.
	(aarch64_normal_frame_base): Likewise.
---
 gdb/aarch64-tdep.c | 27 +++++++++++----------------
 1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
index 9650a7a..c4b7fe8 100644
--- a/gdb/aarch64-tdep.c
+++ b/gdb/aarch64-tdep.c
@@ -934,14 +934,18 @@ aarch64_scan_prologue (struct frame_info *this_frame,
    about the prologue of *THIS_FRAME.  */
 
 static struct aarch64_prologue_cache *
-aarch64_make_prologue_cache (struct frame_info *this_frame)
+aarch64_make_prologue_cache (struct frame_info *this_frame, void **this_cache)
 {
   struct aarch64_prologue_cache *cache;
   CORE_ADDR unwound_fp;
   int reg;
 
+  if (*this_cache)
+    return *this_cache;
+
   cache = FRAME_OBSTACK_ZALLOC (struct aarch64_prologue_cache);
   cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
+  *this_cache = cache;
 
   aarch64_scan_prologue (this_frame, cache);
 
@@ -970,14 +974,11 @@ static void
 aarch64_prologue_this_id (struct frame_info *this_frame,
 			  void **this_cache, struct frame_id *this_id)
 {
-  struct aarch64_prologue_cache *cache;
+  struct aarch64_prologue_cache *cache
+    = aarch64_make_prologue_cache (this_frame, this_cache);
   struct frame_id id;
   CORE_ADDR pc, func;
 
-  if (*this_cache == NULL)
-    *this_cache = aarch64_make_prologue_cache (this_frame);
-  cache = *this_cache;
-
   /* This is meant to halt the backtrace at "_start".  */
   pc = get_frame_pc (this_frame);
   if (pc <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc)
@@ -999,11 +1000,8 @@ aarch64_prologue_prev_register (struct frame_info *this_frame,
 				void **this_cache, int prev_regnum)
 {
   struct gdbarch *gdbarch = get_frame_arch (this_frame);
-  struct aarch64_prologue_cache *cache;
-
-  if (*this_cache == NULL)
-    *this_cache = aarch64_make_prologue_cache (this_frame);
-  cache = *this_cache;
+  struct aarch64_prologue_cache *cache
+    = aarch64_make_prologue_cache (this_frame, this_cache);
 
   /* If we are asked to unwind the PC, then we need to return the LR
      instead.  The prologue may save PC, but it will point into this
@@ -1120,11 +1118,8 @@ struct frame_unwind aarch64_stub_unwind =
 static CORE_ADDR
 aarch64_normal_frame_base (struct frame_info *this_frame, void **this_cache)
 {
-  struct aarch64_prologue_cache *cache;
-
-  if (*this_cache == NULL)
-    *this_cache = aarch64_make_prologue_cache (this_frame);
-  cache = *this_cache;
+  struct aarch64_prologue_cache *cache
+    = aarch64_make_prologue_cache (this_frame, this_cache);
 
   return cache->prev_sp - cache->framesize;
 }
-- 
2.1.0