Re: [PATCH, gimplefe] passes.c: split out pass-skipping logic into subroutines

[Richard Biener <richard dot guenther at gmail dot com>]

On January 6, 2017 2:57:49 AM GMT+01:00, David Malcolm <dmalcolm@redhat.com> wrote:
>The GIMPLE frontend's pass-skipping logic in execute_one_pass is
>somewhat
>awkward.  This patch splits it out into two subroutines to simplify
>things.
>
>No functional change intended (and this may make it easier to
>update the logic so that it can be shared with the RTL frontend).
>
>Successfully bootstrapped&regrtested on x86_64-pc-linux-gnu.
>
>OK for trunk?

OK.

Richard.

>gcc/ChangeLog:
>	* passes.c (execute_one_pass): Split out pass-skipping logic
>	into...
>	(determine_pass_name_match): ...this new function and...
>	(should_skip_pass_p): ...this new function.
>---
>gcc/passes.c | 97
>+++++++++++++++++++++++++++++++++++++++---------------------
> 1 file changed, 63 insertions(+), 34 deletions(-)
>
>diff --git a/gcc/passes.c b/gcc/passes.c
>index 32d964b..31262ed 100644
>--- a/gcc/passes.c
>+++ b/gcc/passes.c
>@@ -2273,6 +2273,67 @@ override_gate_status (opt_pass *pass, tree func,
>bool gate_status)
>   return gate_status;
> }
> 
>+/* Determine if PASS_NAME matches CRITERION.
>+   Not a pure predicate, since it can update CRITERION, to support
>+   matching the Nth invocation of a pass.
>+   Subroutine of should_skip_pass_p.  */
>+
>+static bool
>+determine_pass_name_match (const char *pass_name, char *criterion)
>+{
>+  size_t namelen = strlen (pass_name);
>+  if (! strncmp (pass_name, criterion, namelen))
>+    {
>+      /* The following supports starting with the Nth invocation
>+	 of a pass (where N does not necessarily is equal to the
>+	 dump file suffix).  */
>+      if (criterion[namelen] == '\0'
>+	  || (criterion[namelen] == '1'
>+	      && criterion[namelen + 1] == '\0'))
>+	return true;
>+      else
>+	{
>+	  if (criterion[namelen + 1] == '\0')
>+	    --criterion[namelen];
>+	  return false;
>+	}
>+    }
>+  else
>+    return false;
>+}
>+
>+/* For skipping passes until "startwith" pass.
>+   Return true iff PASS should be skipped.
>+   Clear cfun->pass_startwith when encountering the "startwith" pass,
>+   so that all subsequent passes are run.  */
>+
>+static bool
>+should_skip_pass_p (opt_pass *pass)
>+{
>+  if (!cfun)
>+    return false;
>+  if (!cfun->pass_startwith)
>+    return false;
>+
>+  /* We can't skip the lowering phase yet -- ideally we'd
>+     drive that phase fully via properties.  */
>+  if (!(cfun->curr_properties & PROP_ssa))
>+    return false;
>+
>+  if (determine_pass_name_match (pass->name, cfun->pass_startwith))
>+    {
>+      cfun->pass_startwith = NULL;
>+      return false;
>+    }
>+
>+  /* And also run any property provider.  */
>+  if (pass->properties_provided != 0)
>+    return false;
>+
>+  /* If we get here, then we have a "startwith" that we haven't seen
>yet;
>+     skip the pass.  */
>+  return true;
>+}
> 
> /* Execute PASS. */
> 
>@@ -2313,40 +2374,8 @@ execute_one_pass (opt_pass *pass)
>       return false;
>     }
> 
>-  /* For skipping passes until startwith pass */
>-  if (cfun
>-      && cfun->pass_startwith
>-      /* But we can't skip the lowering phase yet -- ideally we'd
>-         drive that phase fully via properties.  */
>-      && (cfun->curr_properties & PROP_ssa))
>-    {
>-      size_t namelen = strlen (pass->name);
>-      /* We have to at least start when we leave SSA.  */
>-      if (pass->properties_destroyed & PROP_ssa)
>-	cfun->pass_startwith = NULL;
>-      else if (! strncmp (pass->name, cfun->pass_startwith, namelen))
>-	{
>-	  /* The following supports starting with the Nth invocation
>-	     of a pass (where N does not necessarily is equal to the
>-	     dump file suffix).  */
>-	  if (cfun->pass_startwith[namelen] == '\0'
>-	      || (cfun->pass_startwith[namelen] == '1'
>-		  && cfun->pass_startwith[namelen + 1] == '\0'))
>-	    cfun->pass_startwith = NULL;
>-	  else
>-	    {
>-	      if (cfun->pass_startwith[namelen + 1] != '\0')
>-		return true;
>-	      --cfun->pass_startwith[namelen];
>-	      return true;
>-	    }
>-	}
>-      /* And also run any property provider.  */
>-      else if (pass->properties_provided != 0)
>-	;
>-      else
>-	return true;
>-    }
>+  if (should_skip_pass_p (pass))
>+    return true;
> 
>   /* Pass execution event trigger: useful to identify passes being
>      executed.  */