RegExpExec/RegExpTest should not unconditionally speculate cell
https://bugs.webkit.org/show_bug.cgi?id=154901
Reviewed by Benjamin Poulain.
This is a three part change. It all started with a simple goal: end the rage-recompiles in
Octane/regexp by enabling the DFG and FTL to do untyped RegExpExec/RegExpTest. This keeps us
in the optimized code when you do a regexp match on a number, for example.
While implementing this, I realized that DFGOperations.cpp was bad at exception checking. When
it did check for exceptions, it used exec->hadException() instead of vm.exception(). So I
fixed that. I also made sure that the regexp operations checked for exception after doing
toString().
Unfortunately, the introduction of untyped RegExpExec/RegExpTest caused a regression on
Octane/regexp. This was because we were simultaneously scheduling replacement and OSR compiles
of some large functions with the FTL JIT. The OSR compiles were not useful. This was a
regression from the previous changes to make OSR compiles happen sooner. The problem is that
this change also removed the throttling of OSR compiles even in those cases where we suspect
that replacement is more likely. This patch reintroduces that throttling, but only in the
replacement path.
This change ends up being neutral overall.
* dfg/DFGFixupPhase.cpp:
(JSC::DFG::FixupPhase::fixupNode):
* dfg/DFGOperations.cpp:
* dfg/DFGOperations.h:
* dfg/DFGSpeculativeJIT32_64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* dfg/DFGSpeculativeJIT64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* ftl/FTLLowerDFGToB3.cpp:
(JSC::FTL::DFG::LowerDFGToB3::compileRegExpExec):
(JSC::FTL::DFG::LowerDFGToB3::compileRegExpTest):
(JSC::FTL::DFG::LowerDFGToB3::compileNewRegexp):
* tests/stress/regexp-exec-effect-after-exception.js: Added.
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@197492 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp b/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
index af86a46..6b83dcb 100644
--- a/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
+++ b/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
@@ -879,8 +879,14 @@
case RegExpExec:
case RegExpTest: {
- fixEdge<CellUse>(node->child1());
- fixEdge<CellUse>(node->child2());
+ // FIXME: These should probably speculate something stronger than cell.
+ // https://bugs.webkit.org/show_bug.cgi?id=154900
+ if (node->child1()->shouldSpeculateCell()
+ && node->child2()->shouldSpeculateCell()) {
+ fixEdge<CellUse>(node->child1());
+ fixEdge<CellUse>(node->child2());
+ break;
+ }
break;
}
