Changeset 206841 in webkit for trunk/Source/JavaScriptCore/dfg/DFGJITCompiler.cpp

Timestamp:

Oct 5, 2016, 5:50:59 PM (9 years ago)

Author:

[email protected]

Message:

PCToCodeOriginMap builder should use labelIgnoringWatchpoints() inside the DFG
​https://bugs.webkit.org/show_bug.cgi?id=162936

Reviewed by Michael Saboff.

label() may insert nops because of an InvalidationPoint. It does that
because we don't want code that comes after an InvalidationPoint that isn't
effected by the invalidation point to be overwritten if we fire the
InvalidationPoint. PCToCodeOriginMap just grabs labels to build
a mapping, it never emits code that actually jumps to those labels.
Therefore, it should never cause us to emit nops.

• dfg/DFGJITCompiler.cpp:

(JSC::DFG::JITCompiler::compile):
(JSC::DFG::JITCompiler::compileFunction):

• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::runSlowPathGenerators):
(JSC::DFG::SpeculativeJIT::compileCurrentBlock):

File:

• trunk/Source/JavaScriptCore/dfg/DFGJITCompiler.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/dfg/DFGJITCompiler.cpp

@@ -367 +367 @@
     // Generate slow path code.
     m_speculative->runSlowPathGenerators(m_pcToCodeOriginMapBuilder);
-    m_pcToCodeOriginMapBuilder.appendItem(label(), PCToCodeOriginMapBuilder::defaultCodeOrigin());
+    m_pcToCodeOriginMapBuilder.appendItem(labelIgnoringWatchpoints(), PCToCodeOriginMapBuilder::defaultCodeOrigin());
     
     compileExceptionHandlers();
@@ -460 +460 @@
     // Generate slow path code.
     m_speculative->runSlowPathGenerators(m_pcToCodeOriginMapBuilder);
-    m_pcToCodeOriginMapBuilder.appendItem(label(), PCToCodeOriginMapBuilder::defaultCodeOrigin());
+    m_pcToCodeOriginMapBuilder.appendItem(labelIgnoringWatchpoints(), PCToCodeOriginMapBuilder::defaultCodeOrigin());
     
     compileExceptionHandlers();