diff mbox series

PHIOPT: Improve readability of tree_ssa_phiopt_worker

Message ID 20230420010535.336618-1-apinski@marvell.com
State New
Headers
Series PHIOPT: Improve readability of tree_ssa_phiopt_worker |

Commit Message

Andrew Pinski April 20, 2023, 1:05 a.m. UTC 
  This small patch just changes around the code slightly to
make it easier to understand that the cases were handling diamond
shaped BB for both do_store_elim/do_hoist_loads.
There is no effect on code output at all since all of the checks
are the same still.

Note this depends on
https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616241.html
as that allows this to be done.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

gcc/ChangeLog:

	* tree-ssa-phiopt.cc (tree_ssa_phiopt_worker):
	Change the code around slightly to move diamond
	handling for do_store_elim/do_hoist_loads out of
	the big if/else.
---
 gcc/tree-ssa-phiopt.cc | 46 +++++++++++++++++++-----------------------
 1 file changed, 21 insertions(+), 25 deletions(-)

Comments

Jeff Law April 22, 2023, 10 p.m. UTC | #1 
On 4/19/23 19:05, Andrew Pinski via Gcc-patches wrote:
> This small patch just changes around the code slightly to
> make it easier to understand that the cases were handling diamond
> shaped BB for both do_store_elim/do_hoist_loads.
> There is no effect on code output at all since all of the checks
> are the same still.
> 
> Note this depends on
> https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616241.html
> as that allows this to be done.
> 
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
> 
> gcc/ChangeLog:
> 
> 	* tree-ssa-phiopt.cc (tree_ssa_phiopt_worker):
> 	Change the code around slightly to move diamond
> 	handling for do_store_elim/do_hoist_loads out of
> 	the big if/else.
OK.
jeff
diff mbox series

Patch

diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index 8c5c8d8c250..d886c88215b 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -175,28 +175,38 @@  tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads, bool early_p)
 	  std::swap (bb1, bb2);
 	  std::swap (e1, e2);
 	}
-      else if (do_store_elim
-	       && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest)
+      else if (EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest)
+	{
+	  diamond_p = true;
+	  e2 = EDGE_SUCC (bb2, 0);
+	}
+      else
+	continue;
+
+      e1 = EDGE_SUCC (bb1, 0);
+
+      /* Make sure that bb1 is just a fall through.  */
+      if (!single_succ_p (bb1)
+	  || (e1->flags & EDGE_FALLTHRU) == 0)
+	continue;
+
+      if (do_store_elim && diamond_p)
 	{
-	  basic_block bb3 = EDGE_SUCC (bb1, 0)->dest;
+	  basic_block bb3 = e1->dest;
 
-	  if (!single_succ_p (bb1)
-	      || (EDGE_SUCC (bb1, 0)->flags & EDGE_FALLTHRU) == 0
-	      || !single_succ_p (bb2)
-	      || (EDGE_SUCC (bb2, 0)->flags & EDGE_FALLTHRU) == 0
+	  if (!single_succ_p (bb2)
+	      || (e2->flags & EDGE_FALLTHRU) == 0
 	      || EDGE_COUNT (bb3->preds) != 2)
 	    continue;
 	  if (cond_if_else_store_replacement (bb1, bb2, bb3))
 	    cfgchanged = true;
 	  continue;
 	}
-      else if (do_hoist_loads
-	       && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest)
+      else if (do_hoist_loads && diamond_p)
 	{
-	  basic_block bb3 = EDGE_SUCC (bb1, 0)->dest;
+	  basic_block bb3 = e1->dest;
 
 	  if (!FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (cond_stmt)))
-	      && single_succ_p (bb1)
 	      && single_succ_p (bb2)
 	      && single_pred_p (bb1)
 	      && single_pred_p (bb2)
@@ -209,20 +219,6 @@  tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads, bool early_p)
 	    hoist_adjacent_loads (bb, bb1, bb2, bb3);
 	  continue;
 	}
-      else if (EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest)
-	{
-	  diamond_p = true;
-	  e2 = EDGE_SUCC (bb2, 0);
-	}
-      else
-	continue;
-
-      e1 = EDGE_SUCC (bb1, 0);
-
-      /* Make sure that bb1 is just a fall through.  */
-      if (!single_succ_p (bb1)
-	  || (e1->flags & EDGE_FALLTHRU) == 0)
-        continue;
 
       if (do_store_elim && !diamond_p)
 	{