From: Jeff Law <law@redhat.com>
Date: Thu, 12 Jun 2014 17:12:18 +0000 (-0600)
Subject: re PR tree-optimization/61009 (Incorrect jump threading in dom)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=551a6341d5d0fed634c71f710bdae6d7b6b1491e;p=gcc.git

re PR tree-optimization/61009 (Incorrect jump threading in dom)

        PR tree-optimization/61009
	* tree-ssa-threadedge.c (thread_through_normal_block): Correct return
	value when we stop processing a block due to problematic PHIs.

From-SVN: r211586
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a42b94d3a1e..d68262fd341 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-06-12  Jeff Law  <law@redhat.com>
+
+        PR tree-optimization/61009
+	* tree-ssa-threadedge.c (thread_through_normal_block): Correct return
+	value when we stop processing a block due to problematic PHIs.
+
 2014-06-12  Alan Lawrence  <alan.lawrence@arm.com>
 
 	* config/aarch64/arm_neon.h (vmlaq_n_f64, vmlsq_n_f64, vrsrtsq_f64,
diff --git a/gcc/tree-ssa-threadedge.c b/gcc/tree-ssa-threadedge.c
index ba9e1fe30f4..a76a7ce6587 100644
--- a/gcc/tree-ssa-threadedge.c
+++ b/gcc/tree-ssa-threadedge.c
@@ -948,9 +948,12 @@ thread_through_normal_block (edge e,
   if (*backedge_seen_p)
     simplify = dummy_simplify;
 
-  /* PHIs create temporary equivalences.  */
+  /* PHIs create temporary equivalences.
+     Note that if we found a PHI that made the block non-threadable, then
+     we need to bubble that up to our caller in the same manner we do
+     when we prematurely stop processing statements below.  */
   if (!record_temporary_equivalences_from_phis (e, stack))
-    return 0;
+    return -1;
 
   /* Now walk each statement recording any context sensitive
      temporary equivalences we can detect.  */