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Diffstat (limited to 'js/src/jit/mips32/Assembler-mips32.cpp')
-rw-r--r--js/src/jit/mips32/Assembler-mips32.cpp369
1 files changed, 369 insertions, 0 deletions
diff --git a/js/src/jit/mips32/Assembler-mips32.cpp b/js/src/jit/mips32/Assembler-mips32.cpp
new file mode 100644
index 0000000000..8073b8e4ec
--- /dev/null
+++ b/js/src/jit/mips32/Assembler-mips32.cpp
@@ -0,0 +1,369 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * 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/mips32/Assembler-mips32.h"
+
+#include "mozilla/DebugOnly.h"
+#include "mozilla/Maybe.h"
+
+#include "jit/AutoWritableJitCode.h"
+
+using mozilla::DebugOnly;
+
+using namespace js;
+using namespace js::jit;
+
+ABIArgGenerator::ABIArgGenerator()
+ : usedArgSlots_(0),
+ firstArgFloatSize_(0),
+ useGPRForFloats_(false),
+ current_() {}
+
+ABIArg ABIArgGenerator::next(MIRType type) {
+ Register destReg;
+ switch (type) {
+ case MIRType::Int32:
+ case MIRType::Pointer:
+ case MIRType::RefOrNull:
+ case MIRType::StackResults:
+ if (GetIntArgReg(usedArgSlots_, &destReg)) {
+ current_ = ABIArg(destReg);
+ } else {
+ current_ = ABIArg(usedArgSlots_ * sizeof(intptr_t));
+ }
+ usedArgSlots_++;
+ break;
+ case MIRType::Int64:
+ if (!usedArgSlots_) {
+ current_ = ABIArg(a0, a1);
+ usedArgSlots_ = 2;
+ } else if (usedArgSlots_ <= 2) {
+ current_ = ABIArg(a2, a3);
+ usedArgSlots_ = 4;
+ } else {
+ if (usedArgSlots_ < NumIntArgRegs) {
+ usedArgSlots_ = NumIntArgRegs;
+ }
+ usedArgSlots_ += usedArgSlots_ % 2;
+ current_ = ABIArg(usedArgSlots_ * sizeof(intptr_t));
+ usedArgSlots_ += 2;
+ }
+ break;
+ case MIRType::Float32:
+ if (!usedArgSlots_) {
+ current_ = ABIArg(f12.asSingle());
+ firstArgFloatSize_ = 1;
+ } else if (usedArgSlots_ == firstArgFloatSize_) {
+ current_ = ABIArg(f14.asSingle());
+ } else if (useGPRForFloats_ && GetIntArgReg(usedArgSlots_, &destReg)) {
+ current_ = ABIArg(destReg);
+ } else {
+ if (usedArgSlots_ < NumIntArgRegs) {
+ usedArgSlots_ = NumIntArgRegs;
+ }
+ current_ = ABIArg(usedArgSlots_ * sizeof(intptr_t));
+ }
+ usedArgSlots_++;
+ break;
+ case MIRType::Double:
+ if (!usedArgSlots_) {
+ current_ = ABIArg(f12);
+ usedArgSlots_ = 2;
+ firstArgFloatSize_ = 2;
+ } else if (usedArgSlots_ == firstArgFloatSize_) {
+ current_ = ABIArg(f14);
+ usedArgSlots_ = 4;
+ } else if (useGPRForFloats_ && usedArgSlots_ <= 2) {
+ current_ = ABIArg(a2, a3);
+ usedArgSlots_ = 4;
+ } else {
+ if (usedArgSlots_ < NumIntArgRegs) {
+ usedArgSlots_ = NumIntArgRegs;
+ }
+ usedArgSlots_ += usedArgSlots_ % 2;
+ current_ = ABIArg(usedArgSlots_ * sizeof(intptr_t));
+ usedArgSlots_ += 2;
+ }
+ break;
+ default:
+ MOZ_CRASH("Unexpected argument type");
+ }
+ return current_;
+}
+
+uint32_t js::jit::RT(FloatRegister r) {
+ MOZ_ASSERT(r.id() < FloatRegisters::RegisterIdLimit);
+ return r.id() << RTShift;
+}
+
+uint32_t js::jit::RD(FloatRegister r) {
+ MOZ_ASSERT(r.id() < FloatRegisters::RegisterIdLimit);
+ return r.id() << RDShift;
+}
+
+uint32_t js::jit::RZ(FloatRegister r) {
+ MOZ_ASSERT(r.id() < FloatRegisters::RegisterIdLimit);
+ return r.id() << RZShift;
+}
+
+uint32_t js::jit::SA(FloatRegister r) {
+ MOZ_ASSERT(r.id() < FloatRegisters::RegisterIdLimit);
+ return r.id() << SAShift;
+}
+
+void Assembler::executableCopy(uint8_t* buffer) {
+ MOZ_ASSERT(isFinished);
+ m_buffer.executableCopy(buffer);
+}
+
+uintptr_t Assembler::GetPointer(uint8_t* instPtr) {
+ Instruction* inst = (Instruction*)instPtr;
+ return Assembler::ExtractLuiOriValue(inst, inst->next());
+}
+
+static JitCode* CodeFromJump(Instruction* jump) {
+ uint8_t* target = (uint8_t*)Assembler::ExtractLuiOriValue(jump, jump->next());
+ return JitCode::FromExecutable(target);
+}
+
+void Assembler::TraceJumpRelocations(JSTracer* trc, JitCode* code,
+ CompactBufferReader& reader) {
+ while (reader.more()) {
+ JitCode* child =
+ CodeFromJump((Instruction*)(code->raw() + reader.readUnsigned()));
+ TraceManuallyBarrieredEdge(trc, &child, "rel32");
+ }
+}
+
+static void TraceOneDataRelocation(JSTracer* trc,
+ mozilla::Maybe<AutoWritableJitCode>& awjc,
+ JitCode* code, Instruction* inst) {
+ void* ptr = (void*)Assembler::ExtractLuiOriValue(inst, inst->next());
+ void* prior = ptr;
+
+ // No barrier needed since these are constants.
+ TraceManuallyBarrieredGenericPointerEdge(
+ trc, reinterpret_cast<gc::Cell**>(&ptr), "jit-masm-ptr");
+ if (ptr != prior) {
+ if (awjc.isNothing()) {
+ awjc.emplace(code);
+ }
+ AssemblerMIPSShared::UpdateLuiOriValue(inst, inst->next(), uint32_t(ptr));
+ }
+}
+
+/* static */
+void Assembler::TraceDataRelocations(JSTracer* trc, JitCode* code,
+ CompactBufferReader& reader) {
+ mozilla::Maybe<AutoWritableJitCode> awjc;
+ while (reader.more()) {
+ size_t offset = reader.readUnsigned();
+ Instruction* inst = (Instruction*)(code->raw() + offset);
+ TraceOneDataRelocation(trc, awjc, code, inst);
+ }
+}
+
+Assembler::Condition Assembler::UnsignedCondition(Condition cond) {
+ switch (cond) {
+ case Zero:
+ case NonZero:
+ return cond;
+ case LessThan:
+ case Below:
+ return Below;
+ case LessThanOrEqual:
+ case BelowOrEqual:
+ return BelowOrEqual;
+ case GreaterThan:
+ case Above:
+ return Above;
+ case AboveOrEqual:
+ case GreaterThanOrEqual:
+ return AboveOrEqual;
+ default:
+ MOZ_CRASH("unexpected condition");
+ }
+}
+
+Assembler::Condition Assembler::ConditionWithoutEqual(Condition cond) {
+ switch (cond) {
+ case LessThan:
+ case LessThanOrEqual:
+ return LessThan;
+ case Below:
+ case BelowOrEqual:
+ return Below;
+ case GreaterThan:
+ case GreaterThanOrEqual:
+ return GreaterThan;
+ case Above:
+ case AboveOrEqual:
+ return Above;
+ default:
+ MOZ_CRASH("unexpected condition");
+ }
+}
+
+void Assembler::Bind(uint8_t* rawCode, const CodeLabel& label) {
+ if (label.patchAt().bound()) {
+ auto mode = label.linkMode();
+ intptr_t offset = label.patchAt().offset();
+ intptr_t target = label.target().offset();
+
+ if (mode == CodeLabel::RawPointer) {
+ *reinterpret_cast<const void**>(rawCode + offset) = rawCode + target;
+ } else {
+ MOZ_ASSERT(mode == CodeLabel::MoveImmediate ||
+ mode == CodeLabel::JumpImmediate);
+ Instruction* inst = (Instruction*)(rawCode + offset);
+ AssemblerMIPSShared::UpdateLuiOriValue(inst, inst->next(),
+ (uint32_t)(rawCode + target));
+ }
+ }
+}
+
+void Assembler::bind(InstImm* inst, uintptr_t branch, uintptr_t target) {
+ int32_t offset = target - branch;
+ InstImm inst_bgezal = InstImm(op_regimm, zero, rt_bgezal, BOffImm16(0));
+ InstImm inst_beq = InstImm(op_beq, zero, zero, BOffImm16(0));
+
+ // If encoded offset is 4, then the jump must be short
+ if (BOffImm16(inst[0]).decode() == 4) {
+ MOZ_ASSERT(BOffImm16::IsInRange(offset));
+ inst[0].setBOffImm16(BOffImm16(offset));
+ inst[1].makeNop();
+ return;
+ }
+
+ // Generate the long jump for calls because return address has to be the
+ // address after the reserved block.
+ if (inst[0].encode() == inst_bgezal.encode()) {
+ addLongJump(BufferOffset(branch), BufferOffset(target));
+ Assembler::WriteLuiOriInstructions(inst, &inst[1], ScratchRegister,
+ LabelBase::INVALID_OFFSET);
+ inst[2] = InstReg(op_special, ScratchRegister, zero, ra, ff_jalr).encode();
+ // There is 1 nop after this.
+ return;
+ }
+
+ if (BOffImm16::IsInRange(offset)) {
+ bool conditional = (inst[0].encode() != inst_bgezal.encode() &&
+ inst[0].encode() != inst_beq.encode());
+
+ inst[0].setBOffImm16(BOffImm16(offset));
+ inst[1].makeNop();
+
+ // Skip the trailing nops in conditional branches.
+ if (conditional) {
+ inst[2] = InstImm(op_regimm, zero, rt_bgez, BOffImm16(3 * sizeof(void*)))
+ .encode();
+ // There are 2 nops after this
+ }
+ return;
+ }
+
+ if (inst[0].encode() == inst_beq.encode()) {
+ // Handle long unconditional jump.
+ addLongJump(BufferOffset(branch), BufferOffset(target));
+ Assembler::WriteLuiOriInstructions(inst, &inst[1], ScratchRegister,
+ LabelBase::INVALID_OFFSET);
+ inst[2] = InstReg(op_special, ScratchRegister, zero, zero, ff_jr).encode();
+ // There is 1 nop after this.
+ } else {
+ // Handle long conditional jump.
+ inst[0] = invertBranch(inst[0], BOffImm16(5 * sizeof(void*)));
+ // No need for a "nop" here because we can clobber scratch.
+ addLongJump(BufferOffset(branch + sizeof(void*)), BufferOffset(target));
+ Assembler::WriteLuiOriInstructions(&inst[1], &inst[2], ScratchRegister,
+ LabelBase::INVALID_OFFSET);
+ inst[3] = InstReg(op_special, ScratchRegister, zero, zero, ff_jr).encode();
+ // There is 1 nop after this.
+ }
+}
+
+void Assembler::processCodeLabels(uint8_t* rawCode) {
+ for (const CodeLabel& label : codeLabels_) {
+ Bind(rawCode, label);
+ }
+}
+
+uint32_t Assembler::PatchWrite_NearCallSize() { return 4 * sizeof(uint32_t); }
+
+void Assembler::PatchWrite_NearCall(CodeLocationLabel start,
+ CodeLocationLabel toCall) {
+ Instruction* inst = (Instruction*)start.raw();
+ uint8_t* dest = toCall.raw();
+
+ // Overwrite whatever instruction used to be here with a call.
+ // Always use long jump for two reasons:
+ // - Jump has to be the same size because of PatchWrite_NearCallSize.
+ // - Return address has to be at the end of replaced block.
+ // Short jump wouldn't be more efficient.
+ Assembler::WriteLuiOriInstructions(inst, &inst[1], ScratchRegister,
+ (uint32_t)dest);
+ inst[2] = InstReg(op_special, ScratchRegister, zero, ra, ff_jalr);
+ inst[3] = InstNOP();
+}
+
+uint32_t Assembler::ExtractLuiOriValue(Instruction* inst0, Instruction* inst1) {
+ InstImm* i0 = (InstImm*)inst0;
+ InstImm* i1 = (InstImm*)inst1;
+ MOZ_ASSERT(i0->extractOpcode() == ((uint32_t)op_lui >> OpcodeShift));
+ MOZ_ASSERT(i1->extractOpcode() == ((uint32_t)op_ori >> OpcodeShift));
+
+ uint32_t value = i0->extractImm16Value() << 16;
+ value = value | i1->extractImm16Value();
+ return value;
+}
+
+void Assembler::WriteLuiOriInstructions(Instruction* inst0, Instruction* inst1,
+ Register reg, uint32_t value) {
+ *inst0 = InstImm(op_lui, zero, reg, Imm16::Upper(Imm32(value)));
+ *inst1 = InstImm(op_ori, reg, reg, Imm16::Lower(Imm32(value)));
+}
+
+void Assembler::PatchDataWithValueCheck(CodeLocationLabel label,
+ ImmPtr newValue, ImmPtr expectedValue) {
+ PatchDataWithValueCheck(label, PatchedImmPtr(newValue.value),
+ PatchedImmPtr(expectedValue.value));
+}
+
+void Assembler::PatchDataWithValueCheck(CodeLocationLabel label,
+ PatchedImmPtr newValue,
+ PatchedImmPtr expectedValue) {
+ Instruction* inst = (Instruction*)label.raw();
+
+ // Extract old Value
+ DebugOnly<uint32_t> value = Assembler::ExtractLuiOriValue(&inst[0], &inst[1]);
+ MOZ_ASSERT(value == uint32_t(expectedValue.value));
+
+ // Replace with new value
+ AssemblerMIPSShared::UpdateLuiOriValue(inst, inst->next(),
+ uint32_t(newValue.value));
+}
+
+uint32_t Assembler::ExtractInstructionImmediate(uint8_t* code) {
+ InstImm* inst = (InstImm*)code;
+ return Assembler::ExtractLuiOriValue(inst, inst->next());
+}
+
+void Assembler::ToggleCall(CodeLocationLabel inst_, bool enabled) {
+ Instruction* inst = (Instruction*)inst_.raw();
+ InstImm* i0 = (InstImm*)inst;
+ InstImm* i1 = (InstImm*)i0->next();
+ Instruction* i2 = (Instruction*)i1->next();
+
+ MOZ_ASSERT(i0->extractOpcode() == ((uint32_t)op_lui >> OpcodeShift));
+ MOZ_ASSERT(i1->extractOpcode() == ((uint32_t)op_ori >> OpcodeShift));
+
+ if (enabled) {
+ InstReg jalr = InstReg(op_special, ScratchRegister, zero, ra, ff_jalr);
+ *i2 = jalr;
+ } else {
+ InstNOP nop;
+ *i2 = nop;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-20 14:34:57 +0000