Changeset 214901 in webkit for trunk/Source/JavaScriptCore/b3/B3Generate.cpp

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/B3Generate.cpp (modified) (5 diffs)

trunk/Source/JavaScriptCore/b3/B3Generate.cpp

@@ -53 +53 @@
 namespace JSC { namespace B3 {
 
-void prepareForGeneration(Procedure& procedure, unsigned optLevel)
+void prepareForGeneration(Procedure& procedure)
 {
     TimingScope timingScope("prepareForGeneration");
 
-    generateToAir(procedure, optLevel);
-    Air::prepareForGeneration(procedure.code(), optLevel);
+    generateToAir(procedure);
+    Air::prepareForGeneration(procedure.code());
 }
 
@@ -66 +66 @@
 }
 
-void generateToAir(Procedure& procedure, unsigned optLevel)
+void generateToAir(Procedure& procedure)
 {
     TimingScope timingScope("generateToAir");
@@ -81 +81 @@
         validate(procedure);
 
-    if (optLevel >= 2) {
+    if (procedure.optLevel() >= 2) {
         reduceDoubleToFloat(procedure);
         reduceStrength(procedure);
@@ -92 +92 @@
         // FIXME: Add more optimizations here.
         // https://bugs.webkit.org/show_bug.cgi?id=150507
-    } else if (optLevel >= 1) {
+    } else if (procedure.optLevel() >= 1) {
         // FIXME: Explore better "quick mode" optimizations.
         reduceStrength(procedure);
@@ -100 +100 @@
     lowerMacros(procedure);
 
-    if (optLevel >= 2) {
+    if (procedure.optLevel() >= 2) {
         reduceStrength(procedure);