Changeset 242865 in webkit

Timestamp:

Mar 13, 2019, 2:24:50 AM (7 years ago)

Author:

Carlos Garcia Campos

Message:

Merge r242276 - DFG: Loop-invariant code motion (LICM) should not hoist dead code
​https://bugs.webkit.org/show_bug.cgi?id=194945
<rdar://problem/48311657>

Reviewed by Saam Barati.

• dfg/DFGLICMPhase.cpp:

(JSC::DFG::LICMPhase::run):

Location:

releases/WebKitGTK/webkit-2.24

Files:

• JSTests/ChangeLog (modified) (1 diff)
• JSTests/stress/licm-dead-code.js (added)
• Source/JavaScriptCore/ChangeLog (modified) (1 diff)
• Source/JavaScriptCore/dfg/DFGLICMPhase.cpp (modified) (2 diffs)

releases/WebKitGTK/webkit-2.24/JSTests/ChangeLog

@@ -56 +56 @@
         Added a test and a microbenchmark for corner cases of
         Array.prototype.join() with an uninitialized array.
+
+2019-02-27  Robin Morisset  <rmorisset@apple.com>
+
+        DFG: Loop-invariant code motion (LICM) should not hoist dead code
+        https://bugs.webkit.org/show_bug.cgi?id=194945
+        <rdar://problem/48311657>
+
+        Reviewed by Mark Lam.
+
+        * stress/licm-dead-code.js: Added.
 
         * microbenchmarks/array-prototype-join-uninitialized.js: Added.

releases/WebKitGTK/webkit-2.24/Source/JavaScriptCore/ChangeLog

@@ -416 +416 @@
         * runtime/JSString.h:
         * runtime/NativeExecutable.cpp:
+2019-02-27  Robin Morisset  <rmorisset@apple.com>
+
+        DFG: Loop-invariant code motion (LICM) should not hoist dead code
+        https://bugs.webkit.org/show_bug.cgi?id=194945
+        <rdar://problem/48311657>
+
+        Reviewed by Saam Barati.
+
+        * dfg/DFGLICMPhase.cpp:
+        (JSC::DFG::LICMPhase::run):
+
         (JSC::NativeExecutable::hashFor const):
         * runtime/NativeExecutable.h:

releases/WebKitGTK/webkit-2.24/Source/JavaScriptCore/dfg/DFGLICMPhase.cpp

@@ -185 +185 @@
         bool changed = false;
         for (BasicBlock* block : m_graph.blocksInPreOrder()) {
+            if (!block->cfaHasVisited)
+                continue;
+
             const NaturalLoop* loop = m_graph.m_ssaNaturalLoops->innerMostLoopOf(block);
             if (!loop)
@@ -211 +214 @@
             for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
                 Node*& nodeRef = block->at(nodeIndex);
+                if (nodeRef->op() == ForceOSRExit)
+                    break;
                 for (unsigned stackIndex = loopStack.size(); stackIndex--;)
                     changed |= attemptHoist(block, nodeRef, loopStack[stackIndex]);