The Tor Browser: js/src/jit/mips/MoveEmitter-mips.cpp@6474c204b198 (annotated)

js/src/jit/mips/MoveEmitter-mips.cpp@6474c204b198 (annotated)

js/src/jit/mips/MoveEmitter-mips.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  * vim: set ts=8 sts=4 et sw=4 tw=99:
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "jit/mips/MoveEmitter-mips.h"
 using namespace js;
 using namespace js::jit;
 MoveEmitterMIPS::MoveEmitterMIPS(MacroAssemblerMIPSCompat &masm)
   : inCycle_(false),
     masm(masm),
     pushedAtCycle_(-1),
     pushedAtSpill_(-1),
     spilledReg_(InvalidReg),
     spilledFloatReg_(InvalidFloatReg)
 {
     pushedAtStart_ = masm.framePushed();
 }
 void
 MoveEmitterMIPS::emit(const MoveResolver &moves)
 {
     if (moves.hasCycles()) {
         // Reserve stack for cycle resolution
         masm.reserveStack(sizeof(double));
         pushedAtCycle_ = masm.framePushed();
     }
     for (size_t i = 0; i < moves.numMoves(); i++)
         emit(moves.getMove(i));
 }
 MoveEmitterMIPS::~MoveEmitterMIPS()
 {
     assertDone();
 }
 Address
 MoveEmitterMIPS::cycleSlot() const
 {
     int offset = masm.framePushed() - pushedAtCycle_;
     MOZ_ASSERT(Imm16::isInSignedRange(offset));
     return Address(StackPointer, offset);
 }
 int32_t
 MoveEmitterMIPS::getAdjustedOffset(const MoveOperand &operand)
 {
     MOZ_ASSERT(operand.isMemoryOrEffectiveAddress());
     if (operand.base() != StackPointer)
         return operand.disp();
     // Adjust offset if stack pointer has been moved.
     return operand.disp() + masm.framePushed() - pushedAtStart_;
 }
 Address
 MoveEmitterMIPS::getAdjustedAddress(const MoveOperand &operand)
 {
     return Address(operand.base(), getAdjustedOffset(operand));
 }
 Register
 MoveEmitterMIPS::tempReg()
 {
     spilledReg_ = SecondScratchReg;
     return SecondScratchReg;
 }
 void
 MoveEmitterMIPS::breakCycle(const MoveOperand &from, const MoveOperand &to, MoveOp::Type type)
 {
     // There is some pattern:
     //   (A -> B)
     //   (B -> A)
     //
     // This case handles (A -> B), which we reach first. We save B, then allow
     // the original move to continue.
     switch (type) {
       case MoveOp::FLOAT32:
         if (to.isMemory()) {
             FloatRegister temp = ScratchFloatReg;
             masm.loadFloat32(getAdjustedAddress(to), temp);
             masm.storeFloat32(temp, cycleSlot());
         } else {
             masm.storeFloat32(to.floatReg(), cycleSlot());
         }
         break;
       case MoveOp::DOUBLE:
         if (to.isMemory()) {
             FloatRegister temp = ScratchFloatReg;
             masm.loadDouble(getAdjustedAddress(to), temp);
             masm.storeDouble(temp, cycleSlot());
         } else {
             masm.storeDouble(to.floatReg(), cycleSlot());
         }
         break;
       case MoveOp::INT32:
         MOZ_ASSERT(sizeof(uintptr_t) == sizeof(int32_t));
       case MoveOp::GENERAL:
         if (to.isMemory()) {
             Register temp = tempReg();
             masm.loadPtr(getAdjustedAddress(to), temp);
             masm.storePtr(temp, cycleSlot());
         } else {
             // Second scratch register should not be moved by MoveEmitter.
             MOZ_ASSERT(to.reg() != spilledReg_);
             masm.storePtr(to.reg(), cycleSlot());
         }
         break;
       default:
         MOZ_ASSUME_UNREACHABLE("Unexpected move type");
     }
 }
 void
 MoveEmitterMIPS::completeCycle(const MoveOperand &from, const MoveOperand &to, MoveOp::Type type)
 {
     // There is some pattern:
     //   (A -> B)
     //   (B -> A)
     //
     // This case handles (B -> A), which we reach last. We emit a move from the
     // saved value of B, to A.
     switch (type) {
       case MoveOp::FLOAT32:
         if (to.isMemory()) {
             FloatRegister temp = ScratchFloatReg;
             masm.loadFloat32(cycleSlot(), temp);
             masm.storeFloat32(temp, getAdjustedAddress(to));
         } else {
             masm.loadFloat32(cycleSlot(), to.floatReg());
         }
         break;
       case MoveOp::DOUBLE:
         if (to.isMemory()) {
             FloatRegister temp = ScratchFloatReg;
             masm.loadDouble(cycleSlot(), temp);
             masm.storeDouble(temp, getAdjustedAddress(to));
         } else {
             masm.loadDouble(cycleSlot(), to.floatReg());
         }
         break;
       case MoveOp::INT32:
         MOZ_ASSERT(sizeof(uintptr_t) == sizeof(int32_t));
       case MoveOp::GENERAL:
         if (to.isMemory()) {
             Register temp = tempReg();
             masm.loadPtr(cycleSlot(), temp);
             masm.storePtr(temp, getAdjustedAddress(to));
         } else {
             // Second scratch register should not be moved by MoveEmitter.
             MOZ_ASSERT(to.reg() != spilledReg_);
             masm.loadPtr(cycleSlot(), to.reg());
         }
         break;
       default:
         MOZ_ASSUME_UNREACHABLE("Unexpected move type");
     }
 }
 void
 MoveEmitterMIPS::emitMove(const MoveOperand &from, const MoveOperand &to)
 {
     if (from.isGeneralReg()) {
         // Second scratch register should not be moved by MoveEmitter.
         MOZ_ASSERT(from.reg() != spilledReg_);
         if (to.isGeneralReg())
             masm.movePtr(from.reg(), to.reg());
         else if (to.isMemory())
             masm.storePtr(from.reg(), getAdjustedAddress(to));
         else
             MOZ_ASSUME_UNREACHABLE("Invalid emitMove arguments.");
     } else if (from.isMemory()) {
         if (to.isGeneralReg()) {
             masm.loadPtr(getAdjustedAddress(from), to.reg());
         } else if (to.isMemory()) {
             masm.loadPtr(getAdjustedAddress(from), tempReg());
             masm.storePtr(tempReg(), getAdjustedAddress(to));
         } else {
             MOZ_ASSUME_UNREACHABLE("Invalid emitMove arguments.");
         }
     } else if (from.isEffectiveAddress()) {
         if (to.isGeneralReg()) {
             masm.computeEffectiveAddress(getAdjustedAddress(from), to.reg());
         } else if (to.isMemory()) {
             masm.computeEffectiveAddress(getAdjustedAddress(from), tempReg());
             masm.storePtr(tempReg(), getAdjustedAddress(to));
         } else {
             MOZ_ASSUME_UNREACHABLE("Invalid emitMove arguments.");
         }
     } else {
         MOZ_ASSUME_UNREACHABLE("Invalid emitMove arguments.");
     }
 }
 void
 MoveEmitterMIPS::emitFloat32Move(const MoveOperand &from, const MoveOperand &to)
 {
     // Ensure that we can use ScratchFloatReg in memory move.
     MOZ_ASSERT_IF(from.isFloatReg(), from.floatReg() != ScratchFloatReg);
     MOZ_ASSERT_IF(to.isFloatReg(), to.floatReg() != ScratchFloatReg);
     if (from.isFloatReg()) {
         if (to.isFloatReg()) {
             masm.moveFloat32(from.floatReg(), to.floatReg());
         } else if (to.isGeneralReg()) {
             // This should only be used when passing float parameter in a1,a2,a3
             MOZ_ASSERT(to.reg() == a1 || to.reg() == a2 || to.reg() == a3);
             masm.moveFromFloat32(from.floatReg(), to.reg());
         } else {
             MOZ_ASSERT(to.isMemory());
             masm.storeFloat32(from.floatReg(), getAdjustedAddress(to));
         }
     } else if (to.isFloatReg()) {
         MOZ_ASSERT(from.isMemory());
         masm.loadFloat32(getAdjustedAddress(from), to.floatReg());
     } else if (to.isGeneralReg()) {
         MOZ_ASSERT(from.isMemory());
         // This should only be used when passing float parameter in a1,a2,a3
         MOZ_ASSERT(to.reg() == a1 || to.reg() == a2 || to.reg() == a3);
         masm.loadPtr(getAdjustedAddress(from), to.reg());
     } else {
         MOZ_ASSERT(from.isMemory());
         MOZ_ASSERT(to.isMemory());
         masm.loadFloat32(getAdjustedAddress(from), ScratchFloatReg);
         masm.storeFloat32(ScratchFloatReg, getAdjustedAddress(to));
     }
 }
 void
 MoveEmitterMIPS::emitDoubleMove(const MoveOperand &from, const MoveOperand &to)
 {
     // Ensure that we can use ScratchFloatReg in memory move.
     MOZ_ASSERT_IF(from.isFloatReg(), from.floatReg() != ScratchFloatReg);
     MOZ_ASSERT_IF(to.isFloatReg(), to.floatReg() != ScratchFloatReg);
     if (from.isFloatReg()) {
         if (to.isFloatReg()) {
             masm.moveDouble(from.floatReg(), to.floatReg());
         } else if (to.isGeneralReg()) {
             // Used for passing double parameter in a2,a3 register pair.
             // Two moves are added for one double parameter by
             // MacroAssemblerMIPSCompat::passABIArg
             if(to.reg() == a2)
                 masm.moveFromDoubleLo(from.floatReg(), a2);
             else if(to.reg() == a3)
                 masm.moveFromDoubleHi(from.floatReg(), a3);
             else
                 MOZ_ASSUME_UNREACHABLE("Invalid emitDoubleMove arguments.");
         } else {
             MOZ_ASSERT(to.isMemory());
             masm.storeDouble(from.floatReg(), getAdjustedAddress(to));
         }
     } else if (to.isFloatReg()) {
         MOZ_ASSERT(from.isMemory());
         masm.loadDouble(getAdjustedAddress(from), to.floatReg());
     } else if (to.isGeneralReg()) {
         MOZ_ASSERT(from.isMemory());
         // Used for passing double parameter in a2,a3 register pair.
         // Two moves are added for one double parameter by
         // MacroAssemblerMIPSCompat::passABIArg
         if(to.reg() == a2)
             masm.loadPtr(getAdjustedAddress(from), a2);
         else if(to.reg() == a3)
             masm.loadPtr(Address(from.base(), getAdjustedOffset(from) + sizeof(uint32_t)), a3);
         else
             MOZ_ASSUME_UNREACHABLE("Invalid emitDoubleMove arguments.");
     } else {
         MOZ_ASSERT(from.isMemory());
         MOZ_ASSERT(to.isMemory());
         masm.loadDouble(getAdjustedAddress(from), ScratchFloatReg);
         masm.storeDouble(ScratchFloatReg, getAdjustedAddress(to));
     }
 }
 void
 MoveEmitterMIPS::emit(const MoveOp &move)
 {
     const MoveOperand &from = move.from();
     const MoveOperand &to = move.to();
     if (move.isCycleEnd()) {
         MOZ_ASSERT(inCycle_);
         completeCycle(from, to, move.type());
         inCycle_ = false;
         return;
     }
     if (move.isCycleBegin()) {
         MOZ_ASSERT(!inCycle_);
         breakCycle(from, to, move.endCycleType());
         inCycle_ = true;
     }
     switch (move.type()) {
       case MoveOp::FLOAT32:
         emitFloat32Move(from, to);
         break;
       case MoveOp::DOUBLE:
         emitDoubleMove(from, to);
         break;
       case MoveOp::INT32:
         MOZ_ASSERT(sizeof(uintptr_t) == sizeof(int32_t));
       case MoveOp::GENERAL:
         emitMove(from, to);
         break;
       default:
         MOZ_ASSUME_UNREACHABLE("Unexpected move type");
     }
 }
 void
 MoveEmitterMIPS::assertDone()
 {
     MOZ_ASSERT(!inCycle_);
 }
 void
 MoveEmitterMIPS::finish()
 {
     assertDone();
     masm.freeStack(masm.framePushed() - pushedAtStart_);
 }

The Tor Browser / annotate

js/src/jit/mips/MoveEmitter-mips.cpp@6474c204b198 (annotated)

js/src/jit/mips/MoveEmitter-mips.cpp