Changeset 214901 in webkit for trunk/Source/JavaScriptCore/b3/B3Procedure.h

Timestamp:

Apr 4, 2017, 2:48:41 PM (8 years ago)

Author:

[email protected]

Message:

Air::lowerAfterRegAlloc should bail early if it finds no Shuffles or ColdCCalls
​https://bugs.webkit.org/show_bug.cgi?id=170305

Reviewed by Saam Barati.

This reduces and sometimes completely eliminates the need to run lowerAfterRegAlloc().

This lowers the Shuffle for the arguments of a CCall before register allocation unless
the CCall arguments require a real shuffle (like if the CCall arguments were argument
registers). This lowers a ColdCCall like a CCall for optLevel<2.

Finally, lowerAfterRegAlloc() now checks if there are any Shuffles or CCalls before it
does anything else. For wasm at -O1, this means that the phase doesn't run at all. This
is a ~3% wasm -O1 compile time progression.

To make this easy, I changed optLevel into a property of Procedure and Code rather than
an argument we thread through everything. I like how Procedure and Code are dumping
ground classes. This does not bother me. Note that I cloned optLevel into Procedure and
Code so that it's cheap to query inside Air phases.

• b3/B3Compile.cpp:

(JSC::B3::compile):

• b3/B3Compile.h:
• b3/B3Generate.cpp:

(JSC::B3::prepareForGeneration):
(JSC::B3::generateToAir):

• b3/B3Generate.h:
• b3/B3Procedure.cpp:

(JSC::B3::Procedure::setOptLevel):

• b3/B3Procedure.h:

(JSC::B3::Procedure::optLevel):

• b3/air/AirCode.h:

(JSC::B3::Air::Code::isPinned):
(JSC::B3::Air::Code::setOptLevel):
(JSC::B3::Air::Code::optLevel):

• b3/air/AirEmitShuffle.cpp:

(JSC::B3::Air::ShufflePair::bank):
(JSC::B3::Air::ShufflePair::opcode):
(JSC::B3::Air::ShufflePair::inst):
(JSC::B3::Air::emitShuffle):

• b3/air/AirEmitShuffle.h:

(JSC::B3::Air::moveFor):

• b3/air/AirGenerate.cpp:

(JSC::B3::Air::prepareForGeneration):

• b3/air/AirGenerate.h:
• b3/air/AirLowerAfterRegAlloc.cpp:

(JSC::B3::Air::lowerAfterRegAlloc):

• b3/air/AirLowerMacros.cpp:

(JSC::B3::Air::lowerMacros):

• b3/testb3.cpp:

(JSC::B3::compileProc):

• wasm/WasmB3IRGenerator.cpp:

(JSC::Wasm::parseAndCompile):

File:

• trunk/Source/JavaScriptCore/b3/B3Procedure.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/b3/B3Procedure.h

@@ -234 +234 @@
     JS_EXPORT_PRIVATE void pinRegister(Reg);
     
+    JS_EXPORT_PRIVATE void setOptLevel(unsigned value);
+    unsigned optLevel() const { return m_optLevel; }
+    
     // You can turn off used registers calculation. This may speed up compilation a bit. But if
     // you turn it off then you cannot use StackmapGenerationParams::usedRegisters() or
@@ -274 +277 @@
     const void* m_frontendData;
     PCToOriginMap m_pcToOriginMap;
+    unsigned m_optLevel { defaultOptLevel() };
     bool m_needsUsedRegisters { true };
     bool m_hasQuirks { false };