Changeset 221176 in webkit for trunk/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp

Timestamp:

Aug 24, 2017, 6:55:53 PM (8 years ago)

Author:

[email protected]

Message:

Unreviewed, rolling out r221119, r221124, and r221143.
​https://bugs.webkit.org/show_bug.cgi?id=175973

"I think it regressed JSBench by 20%" (Requested by saamyjoon
on #webkit).

Reverted changesets:

"Support compiling catch in the DFG"
​https://bugs.webkit.org/show_bug.cgi?id=174590
​http://trac.webkit.org/changeset/221119

"Unreviewed, build fix in GTK port"
​https://bugs.webkit.org/show_bug.cgi?id=174590
​http://trac.webkit.org/changeset/221124

"DFG::JITCode::osrEntry should get sorted since we perform a
binary search on it"
​https://bugs.webkit.org/show_bug.cgi?id=175893
​http://trac.webkit.org/changeset/221143

File:

• trunk/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp (modified) (6 diffs)

trunk/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp

@@ -42 +42 @@
 BasicBlock* createPreHeader(Graph& graph, BlockInsertionSet& insertionSet, BasicBlock* block)
 {
-    ASSERT_WITH_MESSAGE(!graph.isEntrypoint(block), "An entrypoint should not be in a loop");
-
     // FIXME: If we run this utility on SSA IR, then we may end up with a bizarre arrangement of
     // Upsilons and Phis, like:
@@ -72 +70 @@
     float frequency = 0;
     for (BasicBlock* predecessor : block->predecessors) {
-        ASSERT(graph.m_form != SSA);
-        if (graph.m_cpsDominators->dominates(block, predecessor))
+        if (graph.m_dominators->dominates(block, predecessor))
             continue;
         frequency = std::max(frequency, predecessor->executionCount);
@@ -107 +104 @@
     for (unsigned predecessorIndex = 0; predecessorIndex < block->predecessors.size(); predecessorIndex++) {
         BasicBlock* predecessor = block->predecessors[predecessorIndex];
-        if (graph.m_cpsDominators->dominates(block, predecessor))
+        if (graph.m_dominators->dominates(block, predecessor))
             continue;
         block->predecessors[predecessorIndex--] = block->predecessors.last();
@@ -134 +131 @@
     bool run()
     {
-        m_graph.ensureCPSDominators();
-        m_graph.ensureCPSNaturalLoops();
+        m_graph.ensureDominators();
+        m_graph.ensureNaturalLoops();
         
-        for (unsigned loopIndex = m_graph.m_cpsNaturalLoops->numLoops(); loopIndex--;) {
-            const CPSNaturalLoop& loop = m_graph.m_cpsNaturalLoops->loop(loopIndex);
-            BasicBlock* existingPreHeader = nullptr;
+        for (unsigned loopIndex = m_graph.m_naturalLoops->numLoops(); loopIndex--;) {
+            const NaturalLoop& loop = m_graph.m_naturalLoops->loop(loopIndex);
+            BasicBlock* existingPreHeader = 0;
             bool needsNewPreHeader = false;
-            for (unsigned predecessorIndex = loop.header().node()->predecessors.size(); predecessorIndex--;) {
-                BasicBlock* predecessor = loop.header().node()->predecessors[predecessorIndex];
-                if (m_graph.m_cpsDominators->dominates(loop.header().node(), predecessor))
+            for (unsigned predecessorIndex = loop.header()->predecessors.size(); predecessorIndex--;) {
+                BasicBlock* predecessor = loop.header()->predecessors[predecessorIndex];
+                if (m_graph.m_dominators->dominates(loop.header(), predecessor))
                     continue;
                 if (!existingPreHeader) {
@@ -169 +166 @@
             // if the terminal of the existing pre-header doesn't allow for exit, but the first
             // origin of the loop header does, then we should create a new pre-header.
-            if (!needsNewPreHeader && loop.header().node()->at(0)->origin.exitOK
+            if (!needsNewPreHeader && loop.header()->at(0)->origin.exitOK
                 && !existingPreHeader->terminal()->origin.exitOK)
                 needsNewPreHeader = true;
@@ -176 +173 @@
                 continue;
             
-            createPreHeader(m_graph, m_insertionSet, loop.header().node());
+            createPreHeader(m_graph, m_insertionSet, loop.header());
         }