1857134 - liveRegs copied when it could be moved

Status: NEW

(Core :: JavaScript Engine: JIT, enhancement, P3)

Description

[Randell Jesup [:jesup] (needinfo me)]

** CID 1547070: Performance inefficiencies (COPY_INSTEAD_OF_MOVE)
/js/src/jit/CodeGenerator.cpp: 13776 in js::jit::CodeGenerator::visitOptimizeGetIteratorCache(js::jit::LOptimizeGetIteratorCache *)()

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*** CID 1547070: Performance inefficiencies (COPY_INSTEAD_OF_MOVE)
/js/src/jit/CodeGenerator.cpp: 13776 in js::jit::CodeGenerator::visitOptimizeGetIteratorCache(js::jit::LOptimizeGetIteratorCache )()
13770 LOptimizeGetIteratorCache lir) {
13771 LiveRegisterSet liveRegs = lir->safepoint()->liveRegs();
13772 ValueOperand val = ToValue(lir, LOptimizeGetIteratorCache::ValueIndex);
13773 Register output = ToRegister(lir->output());
13774 Register temp = ToRegister(lir->temp0());
13775

CID 1547070:  Performance inefficiencies  (COPY_INSTEAD_OF_MOVE)
"liveRegs" is copied in call to copy constructor "js::jit::LiveSet<js::jit::RegisterSet>", when it could be moved instead.

13776 IonOptimizeGetIteratorIC ic(liveRegs, val, output, temp);
13777 addIC(lir, allocateIC(ic));
13778 }
13779
13780 void CodeGenerator::visitIteratorMore(LIteratorMore* lir) {
13781 const Register obj = ToRegister(lir->iterator());

** CID 1547069: Performance inefficiencies (COPY_INSTEAD_OF_MOVE)
/js/src/jit/IonIC.h: 676 in js::jit::IonOptimizeGetIteratorIC::IonOptimizeGetIteratorIC(js::jit::LiveSet<js::jit::RegisterSet>, js::jit::ValueOperand, js::jit::Register, js::jit::Register)()

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*** CID 1547069: Performance inefficiencies (COPY_INSTEAD_OF_MOVE)
/js/src/jit/IonIC.h: 676 in js::jit::IonOptimizeGetIteratorIC::IonOptimizeGetIteratorIC(js::jit::LiveSet<js::jit::RegisterSet>, js::jit::ValueOperand, js::jit::Register, js::jit::Register)()
670 Register temp_;
671
672 public:
673 IonOptimizeGetIteratorIC(LiveRegisterSet liveRegs, ValueOperand value,
674 Register output, Register temp)
675 : IonIC(CacheKind::OptimizeGetIterator),

CID 1547069:  Performance inefficiencies  (COPY_INSTEAD_OF_MOVE)
"liveRegs" is copied in call to copy constructor "js::jit::LiveSet<js::jit::RegisterSet>", when it could be moved instead.

676 liveRegs_(liveRegs),
677 value_(value),
678 output_(output),
679 temp_(temp) {}
680
681 ValueOperand value() const { return value_; }