diff mbox series

[4/4] resource.cc: Remove redundant conditionals

Message ID 20240527175406.EFF8920433@pchp3.se.axis.com
State New
Headers show
Series Some improvements to resource.cc, including fixing PR115182 | expand

Commit Message

Hans-Peter Nilsson May 27, 2024, 5:54 p.m. UTC 
Regtested cris-elf.  Ok to commit?

-- >8 --
No functional change.

- We always have a target_hash_table and bb_ticks because
init_resource_info is always called.  These conditionals are
an ancient artifact: it's been quite a while since
resource.cc was used elsewhere than exclusively from reorg.cc

- In mark_target_live_regs, get rid of a now-redundant "if
(tinfo != NULL)" conditional and replace an "if (bb)" with a
gcc_assert.

A "git diff -wb" (ignore whitespace diff) is better at
showing the actual changes.

	* resource.cc (free_resource_info, clear_hashed_info_for_insn): Don't
	check for non-null target_hash_table and bb_ticks.
	(mark_target_live_regs): Ditto.  Replace check for non-NULL result from
	BLOCK_FOR_INSN with a call to gcc_assert.  Fold code conditioned on
	tinfo != NULL.
---
 gcc/resource.cc | 123 ++++++++++++++++++++----------------------------
 1 file changed, 52 insertions(+), 71 deletions(-)

Comments

Jeff Law May 27, 2024, 6:59 p.m. UTC | #1 
On 5/27/24 11:54 AM, Hans-Peter Nilsson wrote:
> Regtested cris-elf.  Ok to commit?
> 
> -- >8 --
> No functional change.
> 
> - We always have a target_hash_table and bb_ticks because
> init_resource_info is always called.  These conditionals are
> an ancient artifact: it's been quite a while since
> resource.cc was used elsewhere than exclusively from reorg.cc
> 
> - In mark_target_live_regs, get rid of a now-redundant "if
> (tinfo != NULL)" conditional and replace an "if (bb)" with a
> gcc_assert.
> 
> A "git diff -wb" (ignore whitespace diff) is better at
> showing the actual changes.
> 
> 	* resource.cc (free_resource_info, clear_hashed_info_for_insn): Don't
> 	check for non-null target_hash_table and bb_ticks.
> 	(mark_target_live_regs): Ditto.  Replace check for non-NULL result from
> 	BLOCK_FOR_INSN with a call to gcc_assert.  Fold code conditioned on
> 	tinfo != NULL.
OK once prereqs are fully ack'd.

jeff
diff mbox series

Patch

diff --git a/gcc/resource.cc b/gcc/resource.cc
index 62bd46f786eb..7c1de8864327 100644
--- a/gcc/resource.cc
+++ b/gcc/resource.cc
@@ -658,49 +658,42 @@  mark_target_live_regs (rtx_insn *insns, rtx target_maybe_return, struct resource
   res->cc = 0;
 
   /* See if we have computed this value already.  */
-  if (target_hash_table != NULL)
-    {
-      for (tinfo = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
-	   tinfo; tinfo = tinfo->next)
-	if (tinfo->uid == INSN_UID (target))
-	  break;
-
-      /* Start by getting the basic block number.  If we have saved
-	 information, we can get it from there unless the insn at the
-	 start of the basic block has been deleted.  */
-      if (tinfo && tinfo->block != -1
-	  && ! BB_HEAD (BASIC_BLOCK_FOR_FN (cfun, tinfo->block))->deleted ())
-	b = tinfo->block;
-    }
+  for (tinfo = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
+       tinfo; tinfo = tinfo->next)
+    if (tinfo->uid == INSN_UID (target))
+      break;
+
+  /* Start by getting the basic block number.  If we have saved
+     information, we can get it from there unless the insn at the
+     start of the basic block has been deleted.  */
+  if (tinfo && tinfo->block != -1
+      && ! BB_HEAD (BASIC_BLOCK_FOR_FN (cfun, tinfo->block))->deleted ())
+    b = tinfo->block;
 
   if (b == -1)
     b = BLOCK_FOR_INSN (target)->index;
   gcc_assert (b != -1);
 
-  if (target_hash_table != NULL)
+  if (tinfo)
     {
-      if (tinfo)
+      /* If the information is up-to-date, use it.  Otherwise, we will
+	 update it below.  */
+      if (b == tinfo->block && tinfo->bb_tick == bb_ticks[b])
 	{
-	  /* If the information is up-to-date, use it.  Otherwise, we will
-	     update it below.  */
-	  if (b == tinfo->block && tinfo->bb_tick == bb_ticks[b])
-	    {
-	      res->regs = tinfo->live_regs;
-	      return;
-	    }
-	}
-      else
-	{
-	  /* Allocate a place to put our results and chain it into the
-	     hash table.  */
-	  tinfo = XNEW (struct target_info);
-	  tinfo->uid = INSN_UID (target);
-	  tinfo->block = b;
-	  tinfo->next
-	    = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
-	  target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME] = tinfo;
+	  res->regs = tinfo->live_regs;
+	  return;
 	}
     }
+  else
+    {
+      /* Allocate a place to put our results and chain it into the hash
+	 table.  */
+      tinfo = XNEW (struct target_info);
+      tinfo->uid = INSN_UID (target);
+      tinfo->block = b;
+      tinfo->next = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
+      target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME] = tinfo;
+    }
 
   CLEAR_HARD_REG_SET (pending_dead_regs);
 
@@ -825,13 +818,12 @@  mark_target_live_regs (rtx_insn *insns, rtx target_maybe_return, struct resource
 	     to be live here still are.  The fallthrough edge may have
 	     left a live register uninitialized.  */
 	  bb = BLOCK_FOR_INSN (real_insn);
-	  if (bb)
-	    {
-	      HARD_REG_SET extra_live;
+	  gcc_assert (bb);
 
-	      REG_SET_TO_HARD_REG_SET (extra_live, DF_LR_IN (bb));
-	      current_live_regs |= extra_live;
-	    }
+	  HARD_REG_SET extra_live;
+
+	  REG_SET_TO_HARD_REG_SET (extra_live, DF_LR_IN (bb));
+	  current_live_regs |= extra_live;
 	}
 
       /* The beginning of the epilogue corresponds to the end of the
@@ -847,10 +839,8 @@  mark_target_live_regs (rtx_insn *insns, rtx target_maybe_return, struct resource
     {
       tinfo->block = b;
       tinfo->bb_tick = bb_ticks[b];
+      tinfo->live_regs = res->regs;
     }
-
-  if (tinfo != NULL)
-    tinfo->live_regs = res->regs;
 }
 
 /* Initialize the resources required by mark_target_live_regs ().
@@ -939,31 +929,25 @@  init_resource_info (rtx_insn *epilogue_insn)
 void
 free_resource_info (void)
 {
-  if (target_hash_table != NULL)
+  int i;
+
+  for (i = 0; i < TARGET_HASH_PRIME; ++i)
     {
-      int i;
+      struct target_info *ti = target_hash_table[i];
 
-      for (i = 0; i < TARGET_HASH_PRIME; ++i)
+      while (ti)
 	{
-	  struct target_info *ti = target_hash_table[i];
-
-	  while (ti)
-	    {
-	      struct target_info *next = ti->next;
-	      free (ti);
-	      ti = next;
-	    }
+	  struct target_info *next = ti->next;
+	  free (ti);
+	  ti = next;
 	}
-
-      free (target_hash_table);
-      target_hash_table = NULL;
     }
 
-  if (bb_ticks != NULL)
-    {
-      free (bb_ticks);
-      bb_ticks = NULL;
-    }
+  free (target_hash_table);
+  target_hash_table = NULL;
+
+  free (bb_ticks);
+  bb_ticks = NULL;
 
   free_bb_for_insn ();
 }
@@ -975,16 +959,13 @@  clear_hashed_info_for_insn (rtx_insn *insn)
 {
   struct target_info *tinfo;
 
-  if (target_hash_table != NULL)
-    {
-      for (tinfo = target_hash_table[INSN_UID (insn) % TARGET_HASH_PRIME];
-	   tinfo; tinfo = tinfo->next)
-	if (tinfo->uid == INSN_UID (insn))
-	  break;
+  for (tinfo = target_hash_table[INSN_UID (insn) % TARGET_HASH_PRIME];
+       tinfo; tinfo = tinfo->next)
+    if (tinfo->uid == INSN_UID (insn))
+      break;
 
-      if (tinfo)
-	tinfo->block = -1;
-    }
+  if (tinfo)
+    tinfo->block = -1;
 }
 
 /* Clear any hashed information that we have stored for instructions