Changeset 206472 in webkit

Timestamp:

Sep 27, 2016 4:54:28 PM (8 years ago)

Author:

fpizlo@apple.com

Message:

B3::lowerMacros forgets to before->updatePredecessorsAfter() when lowering ChillMod on ARM64
​https://bugs.webkit.org/show_bug.cgi?id=162644

Reviewed by Keith Miller.

JSTests:

• stress/chill-mod-chill-mod.js: Added.

(foo):

Source/JavaScriptCore:

If you forget to update the predecessors of your successors, then bad things will happen if you
do something that requires accurate predecessors for correctness. lowerMacros() uses
BlockInsertionSet, which relies on accurate predecessors.

• b3/B3LowerMacros.cpp:

Location:

trunk

Files:

• JSTests/ChangeLog (modified) (1 diff)
• JSTests/stress/chill-mod-chill-mod.js (added)
• Source/JavaScriptCore/ChangeLog (modified) (1 diff)
• Source/JavaScriptCore/b3/B3LowerMacros.cpp (modified) (1 diff)

trunk/JSTests/ChangeLog

@@ +1 @@
+2016-09-27  Filip Pizlo  <fpizlo@apple.com>
+
+        B3::lowerMacros forgets to before->updatePredecessorsAfter() when lowering ChillMod on ARM64
+        https://bugs.webkit.org/show_bug.cgi?id=162644
+
+        Reviewed by Keith Miller.
+
+        * stress/chill-mod-chill-mod.js: Added.
+        (foo):
+
 2016-09-26  Csaba Osztrogonác  <oszi@inf.u-szeged.hu>
 

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2016-09-27  Filip Pizlo  <fpizlo@apple.com>
+
+        B3::lowerMacros forgets to before->updatePredecessorsAfter() when lowering ChillMod on ARM64
+        https://bugs.webkit.org/show_bug.cgi?id=162644
+
+        Reviewed by Keith Miller.
+
+        If you forget to update the predecessors of your successors, then bad things will happen if you
+        do something that requires accurate predecessors for correctness. lowerMacros() uses
+        BlockInsertionSet, which relies on accurate predecessors.
+
+        * b3/B3LowerMacros.cpp:
+
 2016-09-27  JF Bastien  <jfbastien@apple.com>
 

trunk/Source/JavaScriptCore/b3/B3LowerMacros.cpp

@@ -148 +148 @@
                     zeroResult->setPhi(phi);
                     m_value->replaceWithIdentity(phi);
+                    before->updatePredecessorsAfter();
                     m_changed = true;
                 } else