[PATCH 01/11] btrace: Use struct btrace_thread_info fields directly.

[Tim Wiederhake <tim dot wiederhake at intel dot com>]

This will later allow to remove BEGIN and END fields.

2017-02-17  Tim Wiederhake  <tim.wiederhake@intel.com>

gdb/ChangeLog:

	* btrace.c (btrace_compute_ftrace_bts, ftrace_add_pt): Use struct
	btrace_thread_info fields directly.
	(btrace_compute_ftrace_pt): Adjusted for change in ftrace_add_pt.


---
 gdb/btrace.c | 94 +++++++++++++++++++++++++++---------------------------------
 1 file changed, 43 insertions(+), 51 deletions(-)

diff --git a/gdb/btrace.c b/gdb/btrace.c
index 95dc7ab..14a16a2 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -976,16 +976,13 @@ btrace_compute_ftrace_bts (struct thread_info *tp,
 			   VEC (bfun_s) **gaps)
 {
   struct btrace_thread_info *btinfo;
-  struct btrace_function *begin, *end;
   struct gdbarch *gdbarch;
   unsigned int blk;
   int level;
 
   gdbarch = target_gdbarch ();
   btinfo = &tp->btrace;
-  begin = btinfo->begin;
-  end = btinfo->end;
-  level = begin != NULL ? -btinfo->level : INT_MAX;
+  level = btinfo->begin != NULL ? -btinfo->level : INT_MAX;
   blk = VEC_length (btrace_block_s, btrace->blocks);
 
   while (blk != 0)
@@ -1007,27 +1004,27 @@ btrace_compute_ftrace_bts (struct thread_info *tp,
 	  if (block->end < pc)
 	    {
 	      /* Indicate the gap in the trace.  */
-	      end = ftrace_new_gap (end, BDE_BTS_OVERFLOW);
-	      if (begin == NULL)
-		begin = end;
+	      btinfo->end = ftrace_new_gap (btinfo->end, BDE_BTS_OVERFLOW);
+	      if (btinfo->begin == NULL)
+		btinfo->begin = btinfo->end;
 
-	      VEC_safe_push (bfun_s, *gaps, end);
+	      VEC_safe_push (bfun_s, *gaps, btinfo->end);
 
 	      warning (_("Recorded trace may be corrupted at instruction "
-			 "%u (pc = %s)."), end->insn_offset - 1,
+			 "%u (pc = %s)."), btinfo->end->insn_offset - 1,
 		       core_addr_to_string_nz (pc));
 
 	      break;
 	    }
 
-	  end = ftrace_update_function (end, pc);
-	  if (begin == NULL)
-	    begin = end;
+	  btinfo->end = ftrace_update_function (btinfo->end, pc);
+	  if (btinfo->begin == NULL)
+	    btinfo->begin = btinfo->end;
 
 	  /* Maintain the function level offset.
 	     For all but the last block, we do it here.  */
 	  if (blk != 0)
-	    level = std::min (level, end->level);
+	    level = std::min (level, btinfo->end->level);
 
 	  size = 0;
 	  TRY
@@ -1044,7 +1041,7 @@ btrace_compute_ftrace_bts (struct thread_info *tp,
 	  insn.iclass = ftrace_classify_insn (gdbarch, pc);
 	  insn.flags = 0;
 
-	  ftrace_update_insns (end, &insn);
+	  ftrace_update_insns (btinfo->end, &insn);
 
 	  /* We're done once we pushed the instruction at the end.  */
 	  if (block->end == pc)
@@ -1055,12 +1052,12 @@ btrace_compute_ftrace_bts (struct thread_info *tp,
 	    {
 	      /* Indicate the gap in the trace.  We just added INSN so we're
 		 not at the beginning.  */
-	      end = ftrace_new_gap (end, BDE_BTS_INSN_SIZE);
+	      btinfo->end = ftrace_new_gap (btinfo->end, BDE_BTS_INSN_SIZE);
 
-	      VEC_safe_push (bfun_s, *gaps, end);
+	      VEC_safe_push (bfun_s, *gaps, btinfo->end);
 
 	      warning (_("Recorded trace may be incomplete at instruction %u "
-			 "(pc = %s)."), end->insn_offset - 1,
+			 "(pc = %s)."), btinfo->end->insn_offset - 1,
 		       core_addr_to_string_nz (pc));
 
 	      break;
@@ -1075,13 +1072,10 @@ btrace_compute_ftrace_bts (struct thread_info *tp,
 	     and is not really part of the execution history, it shouldn't
 	     affect the level.  */
 	  if (blk == 0)
-	    level = std::min (level, end->level);
+	    level = std::min (level, btinfo->end->level);
 	}
     }
 
-  btinfo->begin = begin;
-  btinfo->end = end;
-
   /* LEVEL is the minimal function level of all btrace function segments.
      Define the global level offset to -LEVEL so all function levels are
      normalized to start at zero.  */
@@ -1126,16 +1120,13 @@ pt_btrace_insn_flags (const struct pt_insn *insn)
 
 static void
 ftrace_add_pt (struct pt_insn_decoder *decoder,
-	       struct btrace_function **pbegin,
-	       struct btrace_function **pend, int *plevel,
-	       VEC (bfun_s) **gaps)
+	       struct btrace_thread_info *btinfo,
+	       int *plevel, VEC (bfun_s) **gaps)
 {
-  struct btrace_function *begin, *end, *upd;
+  struct btrace_function *upd;
   uint64_t offset;
   int errcode;
 
-  begin = *pbegin;
-  end = *pend;
   for (;;)
     {
       struct btrace_insn btinsn;
@@ -1158,7 +1149,7 @@ ftrace_add_pt (struct pt_insn_decoder *decoder,
 	    break;
 
 	  /* Look for gaps in the trace - unless we're at the beginning.  */
-	  if (begin != NULL)
+	  if (btinfo->begin != NULL)
 	    {
 	      /* Tracing is disabled and re-enabled each time we enter the
 		 kernel.  Most times, we continue from the same instruction we
@@ -1167,69 +1158,70 @@ ftrace_add_pt (struct pt_insn_decoder *decoder,
 		 from some other instruction.  Indicate this as a trace gap.  */
 	      if (insn.enabled)
 		{
-		  *pend = end = ftrace_new_gap (end, BDE_PT_DISABLED);
+		  btinfo->end = ftrace_new_gap (btinfo->end, BDE_PT_DISABLED);
 
-		  VEC_safe_push (bfun_s, *gaps, end);
+		  VEC_safe_push (bfun_s, *gaps, btinfo->end);
 
 		  pt_insn_get_offset (decoder, &offset);
 
 		  warning (_("Non-contiguous trace at instruction %u (offset "
 			     "= 0x%" PRIx64 ", pc = 0x%" PRIx64 ")."),
-			   end->insn_offset - 1, offset, insn.ip);
+			   btinfo->end->insn_offset - 1, offset, insn.ip);
 		}
 	    }
 
 	  /* Indicate trace overflows.  */
 	  if (insn.resynced)
 	    {
-	      *pend = end = ftrace_new_gap (end, BDE_PT_OVERFLOW);
-	      if (begin == NULL)
-		*pbegin = begin = end;
+	      btinfo->end = ftrace_new_gap (btinfo->end, BDE_PT_OVERFLOW);
+	      if (btinfo->begin == NULL)
+		btinfo->begin = btinfo->end;
 
-	      VEC_safe_push (bfun_s, *gaps, end);
+	      VEC_safe_push (bfun_s, *gaps, btinfo->end);
 
 	      pt_insn_get_offset (decoder, &offset);
 
 	      warning (_("Overflow at instruction %u (offset = 0x%" PRIx64
-			 ", pc = 0x%" PRIx64 ")."), end->insn_offset - 1,
-		       offset, insn.ip);
+			 ", pc = 0x%" PRIx64 ")."),
+		       btinfo->end->insn_offset - 1, offset, insn.ip);
 	    }
 
-	  upd = ftrace_update_function (end, insn.ip);
-	  if (upd != end)
+	  upd = ftrace_update_function (btinfo->end, insn.ip);
+	  if (upd != btinfo->end)
 	    {
-	      *pend = end = upd;
+	      btinfo->end = upd;
 
-	      if (begin == NULL)
-		*pbegin = begin = upd;
+	      if (btinfo->begin == NULL)
+		btinfo->begin = upd;
 	    }
 
 	  /* Maintain the function level offset.  */
-	  *plevel = std::min (*plevel, end->level);
+	  *plevel = std::min (*plevel, btinfo->end->level);
 
 	  btinsn.pc = (CORE_ADDR) insn.ip;
 	  btinsn.size = (gdb_byte) insn.size;
 	  btinsn.iclass = pt_reclassify_insn (insn.iclass);
 	  btinsn.flags = pt_btrace_insn_flags (&insn);
 
-	  ftrace_update_insns (end, &btinsn);
+	  ftrace_update_insns (btinfo->end, &btinsn);
 	}
 
       if (errcode == -pte_eos)
 	break;
 
       /* Indicate the gap in the trace.  */
-      *pend = end = ftrace_new_gap (end, errcode);
-      if (begin == NULL)
-	*pbegin = begin = end;
+      btinfo->end = ftrace_new_gap (btinfo->end, errcode);
+      if (btinfo->begin == NULL)
+	btinfo->begin = btinfo->end;
 
-      VEC_safe_push (bfun_s, *gaps, end);
+      VEC_safe_push (bfun_s, *gaps, btinfo->end);
 
       pt_insn_get_offset (decoder, &offset);
 
       warning (_("Decode error (%d) at instruction %u (offset = 0x%" PRIx64
-		 ", pc = 0x%" PRIx64 "): %s."), errcode, end->insn_offset - 1,
-	       offset, insn.ip, pt_errstr (pt_errcode (errcode)));
+		 ", pc = 0x%" PRIx64 "): %s."), errcode,
+	       btinfo->end->insn_offset - 1, offset, insn.ip,
+	       pt_errstr (pt_errcode (errcode)));
     }
 }
 
@@ -1343,7 +1335,7 @@ btrace_compute_ftrace_pt (struct thread_info *tp,
 	error (_("Failed to configure the Intel Processor Trace decoder: "
 		 "%s."), pt_errstr (pt_errcode (errcode)));
 
-      ftrace_add_pt (decoder, &btinfo->begin, &btinfo->end, &level, gaps);
+      ftrace_add_pt (decoder, btinfo, &level, gaps);
     }
   CATCH (error, RETURN_MASK_ALL)
     {
-- 
2.7.4