dart-sdk/runtime/vm/instructions_riscv.cc
Ryan Macnak 2ebfc9fa6d [vm, ffi] Fix some confused register usage during callbacks.
EmitNativeMove is also used during NativeParamterInstr, not just FfiCallInstr, so the trick with WithIntermediateMarshalling doesn't work. Instead, move arguments to their final register in the prologue of FfiCallInstr and remove conflicting uses within FfiCallInstr.

TEST=ffi_2/function_callbacks_test
Bug: https://github.com/dart-lang/sdk/issues/48164
Change-Id: I652ab714dbfcb092dc5a23e4596f77136d91ffde
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/240324
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2022-04-07 19:44:48 +00:00

466 lines
15 KiB
C++

// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/globals.h" // Needed here to get TARGET_ARCH_RISCV*.
#if defined(TARGET_ARCH_RISCV32) || defined(TARGET_ARCH_RISCV64)
#include "vm/instructions.h"
#include "vm/instructions_riscv.h"
#include "vm/constants.h"
#include "vm/cpu.h"
#include "vm/object.h"
#include "vm/object_store.h"
#include "vm/reverse_pc_lookup_cache.h"
namespace dart {
CallPattern::CallPattern(uword pc, const Code& code)
: object_pool_(ObjectPool::Handle(code.GetObjectPool())),
target_code_pool_index_(-1) {
ASSERT(code.ContainsInstructionAt(pc));
// [lui,add,]lx CODE_REG, ##(pp)
// xxxxxxxx lx ra, ##(CODE_REG)
// xxxx jalr ra
// Last instruction: jalr ra.
ASSERT(*reinterpret_cast<uint16_t*>(pc - 2) == 0x9082);
Register reg;
InstructionPattern::DecodeLoadWordFromPool(pc - 6, &reg,
&target_code_pool_index_);
ASSERT(reg == CODE_REG);
}
ICCallPattern::ICCallPattern(uword pc, const Code& code)
: object_pool_(ObjectPool::Handle(code.GetObjectPool())),
target_pool_index_(-1),
data_pool_index_(-1) {
ASSERT(code.ContainsInstructionAt(pc));
// [lui,add,]lx IC_DATA_REG, ##(pp)
// [lui,add,]lx CODE_REG, ##(pp)
// xxxxxxxx lx ra, ##(CODE_REG)
// xxxx jalr ra
// Last instruction: jalr ra.
ASSERT(*reinterpret_cast<uint16_t*>(pc - 2) == 0x9082);
Register reg;
uword data_load_end = InstructionPattern::DecodeLoadWordFromPool(
pc - 6, &reg, &target_pool_index_);
ASSERT(reg == CODE_REG);
InstructionPattern::DecodeLoadWordFromPool(data_load_end, &reg,
&data_pool_index_);
ASSERT(reg == IC_DATA_REG);
}
NativeCallPattern::NativeCallPattern(uword pc, const Code& code)
: object_pool_(ObjectPool::Handle(code.GetObjectPool())),
end_(pc),
native_function_pool_index_(-1),
target_code_pool_index_(-1) {
ASSERT(code.ContainsInstructionAt(pc));
// [lui,add,]lx t5, ##(pp)
// [lui,add,]lx CODE_REG, ##(pp)
// xxxxxxxx lx ra, ##(CODE_REG)
// xxxx jalr ra
// Last instruction: jalr ra.
ASSERT(*reinterpret_cast<uint16_t*>(pc - 2) == 0x9082);
Register reg;
uword native_function_load_end = InstructionPattern::DecodeLoadWordFromPool(
pc - 6, &reg, &target_code_pool_index_);
ASSERT(reg == CODE_REG);
InstructionPattern::DecodeLoadWordFromPool(native_function_load_end, &reg,
&native_function_pool_index_);
ASSERT(reg == T5);
}
CodePtr NativeCallPattern::target() const {
return static_cast<CodePtr>(object_pool_.ObjectAt(target_code_pool_index_));
}
void NativeCallPattern::set_target(const Code& target) const {
object_pool_.SetObjectAt(target_code_pool_index_, target);
// No need to flush the instruction cache, since the code is not modified.
}
NativeFunction NativeCallPattern::native_function() const {
return reinterpret_cast<NativeFunction>(
object_pool_.RawValueAt(native_function_pool_index_));
}
void NativeCallPattern::set_native_function(NativeFunction func) const {
object_pool_.SetRawValueAt(native_function_pool_index_,
reinterpret_cast<uword>(func));
}
// Decodes a load sequence ending at 'end' (the last instruction of the load
// sequence is the instruction before the one at end). Returns a pointer to
// the first instruction in the sequence. Returns the register being loaded
// and the loaded immediate value in the output parameters 'reg' and 'value'
// respectively.
uword InstructionPattern::DecodeLoadWordImmediate(uword end,
Register* reg,
intptr_t* value) {
UNIMPLEMENTED();
return 0;
}
static bool DecodeLoadX(uword end,
Register* dst,
Register* base,
intptr_t* offset,
intptr_t* length) {
Instr instr(*reinterpret_cast<uint32_t*>(end - 4));
#if XLEN == 32
if (instr.opcode() == LOAD && instr.funct3() == LW) {
#elif XLEN == 64
if (instr.opcode() == LOAD && instr.funct3() == LD) {
#endif
*dst = instr.rd();
*base = instr.rs1();
*offset = instr.itype_imm();
*length = 4;
return true;
}
CInstr cinstr(*reinterpret_cast<uint16_t*>(end - 2));
#if XLEN == 32
if (cinstr.opcode() == C_LW) {
#elif XLEN == 64
if (cinstr.opcode() == C_LD) {
#endif
*dst = cinstr.rdp();
*base = cinstr.rs1p();
#if XLEN == 32
*offset = cinstr.mem4_imm();
#elif XLEN == 64
*offset = cinstr.mem8_imm();
#endif
*length = 2;
return true;
}
return false;
}
static bool DecodeLUI(uword end,
Register* dst,
intptr_t* imm,
intptr_t* length) {
Instr instr(*reinterpret_cast<uint32_t*>(end - 4));
if (instr.opcode() == LUI) {
*dst = instr.rd();
*imm = instr.utype_imm();
*length = 4;
return true;
}
CInstr cinstr(*reinterpret_cast<uint16_t*>(end - 2));
if (cinstr.opcode() == C_LUI) {
*dst = cinstr.rd();
*imm = cinstr.u_imm();
*length = 2;
return true;
}
return false;
}
// See comment in instructions_arm64.h
uword InstructionPattern::DecodeLoadWordFromPool(uword end,
Register* reg,
intptr_t* index) {
// [c.]lx dst, offset(pp)
// or
// [c.]lui dst, hi
// c.add dst, dst, pp
// [c.]lx dst, lo(dst)
Register base;
intptr_t lo, length;
if (!DecodeLoadX(end, reg, &base, &lo, &length)) {
UNREACHABLE();
}
if (base == PP) {
// PP is untagged on RISCV.
*index = ObjectPool::IndexFromOffset(lo - kHeapObjectTag);
return end - length;
}
ASSERT(base == *reg);
end -= length;
CInstr add_instr(*reinterpret_cast<uint16_t*>(end - 2));
ASSERT(add_instr.opcode() ==
C_MV); // Not C_ADD, which extends past the opcode proper.
ASSERT(add_instr.rd() == base);
ASSERT(add_instr.rs1() == base);
ASSERT(add_instr.rs2() == PP);
end -= 2;
Register dst;
intptr_t hi;
if (!DecodeLUI(end, &dst, &hi, &length)) {
UNREACHABLE();
}
ASSERT(dst == base);
// PP is untagged on RISC-V.
*index = ObjectPool::IndexFromOffset(hi + lo - kHeapObjectTag);
return end - length;
}
bool DecodeLoadObjectFromPoolOrThread(uword pc, const Code& code, Object* obj) {
ASSERT(code.ContainsInstructionAt(pc));
uint16_t parcel = *reinterpret_cast<uint16_t*>(pc);
if (IsCInstruction(parcel)) {
CInstr instr(parcel);
#if XLEN == 32
if (instr.opcode() == C_LW) {
intptr_t offset = instr.mem4_imm();
#elif XLEN == 64
if (instr.opcode() == C_LD) {
intptr_t offset = instr.mem8_imm();
#endif
if (instr.rs1p() == PP) {
// PP is untagged on RISC-V.
if (!Utils::IsAligned(offset, kWordSize)) {
return false; // Being used as argument register A5.
}
intptr_t index = ObjectPool::IndexFromOffset(offset - kHeapObjectTag);
const ObjectPool& pool = ObjectPool::Handle(code.GetObjectPool());
if (!pool.IsNull() && (index < pool.Length()) &&
(pool.TypeAt(index) == ObjectPool::EntryType::kTaggedObject)) {
*obj = pool.ObjectAt(index);
return true;
}
} else if (instr.rs1p() == THR) {
return Thread::ObjectAtOffset(offset, obj);
}
}
} else {
Instr instr(*reinterpret_cast<uint32_t*>(pc));
#if XLEN == 32
if (instr.opcode() == LOAD && instr.funct3() == LW) {
#elif XLEN == 64
if (instr.opcode() == LOAD && instr.funct3() == LD) {
#endif
intptr_t offset = instr.itype_imm();
if (instr.rs1() == PP) {
// PP is untagged on RISC-V.
if (!Utils::IsAligned(offset, kWordSize)) {
return false; // Being used as argument register A5.
}
intptr_t index = ObjectPool::IndexFromOffset(offset - kHeapObjectTag);
const ObjectPool& pool = ObjectPool::Handle(code.GetObjectPool());
if (!pool.IsNull() && (index < pool.Length()) &&
(pool.TypeAt(index) == ObjectPool::EntryType::kTaggedObject)) {
*obj = pool.ObjectAt(index);
return true;
}
} else if (instr.rs1() == THR) {
return Thread::ObjectAtOffset(offset, obj);
}
}
if ((instr.opcode() == OPIMM) && (instr.funct3() == ADDI) &&
(instr.rs1() == NULL_REG)) {
if (instr.itype_imm() == 0) {
*obj = Object::null();
return true;
}
if (instr.itype_imm() == kTrueOffsetFromNull) {
*obj = Object::bool_true().ptr();
return true;
}
if (instr.itype_imm() == kFalseOffsetFromNull) {
*obj = Object::bool_false().ptr();
return true;
}
}
}
// TODO(riscv): Loads with offsets beyond 12 bits.
return false;
}
// Encodes a load sequence ending at 'end'. Encodes a fixed length two
// instruction load from the pool pointer in PP using the destination
// register reg as a temporary for the base address.
// Assumes that the location has already been validated for patching.
void InstructionPattern::EncodeLoadWordFromPoolFixed(uword end,
int32_t offset) {
UNIMPLEMENTED();
}
CodePtr CallPattern::TargetCode() const {
return static_cast<CodePtr>(object_pool_.ObjectAt(target_code_pool_index_));
}
void CallPattern::SetTargetCode(const Code& target) const {
object_pool_.SetObjectAt(target_code_pool_index_, target);
// No need to flush the instruction cache, since the code is not modified.
}
ObjectPtr ICCallPattern::Data() const {
return object_pool_.ObjectAt(data_pool_index_);
}
void ICCallPattern::SetData(const Object& data) const {
ASSERT(data.IsArray() || data.IsICData() || data.IsMegamorphicCache());
object_pool_.SetObjectAt(data_pool_index_, data);
}
CodePtr ICCallPattern::TargetCode() const {
return static_cast<CodePtr>(object_pool_.ObjectAt(target_pool_index_));
}
void ICCallPattern::SetTargetCode(const Code& target) const {
object_pool_.SetObjectAt(target_pool_index_, target);
// No need to flush the instruction cache, since the code is not modified.
}
SwitchableCallPatternBase::SwitchableCallPatternBase(
const ObjectPool& object_pool)
: object_pool_(object_pool), data_pool_index_(-1), target_pool_index_(-1) {}
ObjectPtr SwitchableCallPatternBase::data() const {
return object_pool_.ObjectAt(data_pool_index_);
}
void SwitchableCallPatternBase::SetData(const Object& data) const {
ASSERT(!Object::Handle(object_pool_.ObjectAt(data_pool_index_)).IsCode());
object_pool_.SetObjectAt(data_pool_index_, data);
}
SwitchableCallPattern::SwitchableCallPattern(uword pc, const Code& code)
: SwitchableCallPatternBase(ObjectPool::Handle(code.GetObjectPool())) {
ASSERT(code.ContainsInstructionAt(pc));
UNIMPLEMENTED();
}
uword SwitchableCallPattern::target_entry() const {
return Code::Handle(Code::RawCast(object_pool_.ObjectAt(target_pool_index_)))
.MonomorphicEntryPoint();
}
void SwitchableCallPattern::SetTarget(const Code& target) const {
ASSERT(Object::Handle(object_pool_.ObjectAt(target_pool_index_)).IsCode());
object_pool_.SetObjectAt(target_pool_index_, target);
}
BareSwitchableCallPattern::BareSwitchableCallPattern(uword pc)
: SwitchableCallPatternBase(ObjectPool::Handle(
IsolateGroup::Current()->object_store()->global_object_pool())) {
// [lui,add,]lx RA, ##(pp)
// [lui,add,]lx IC_DATA_REG, ##(pp)
// xxxx jalr RA
// Last instruction: jalr ra.
ASSERT(*reinterpret_cast<uint16_t*>(pc - 2) == 0x9082);
Register reg;
uword target_load_end = InstructionPattern::DecodeLoadWordFromPool(
pc - 2, &reg, &data_pool_index_);
ASSERT_EQUAL(reg, IC_DATA_REG);
InstructionPattern::DecodeLoadWordFromPool(target_load_end, &reg,
&target_pool_index_);
ASSERT_EQUAL(reg, RA);
}
uword BareSwitchableCallPattern::target_entry() const {
return object_pool_.RawValueAt(target_pool_index_);
}
void BareSwitchableCallPattern::SetTarget(const Code& target) const {
ASSERT(object_pool_.TypeAt(target_pool_index_) ==
ObjectPool::EntryType::kImmediate);
object_pool_.SetRawValueAt(target_pool_index_,
target.MonomorphicEntryPoint());
}
ReturnPattern::ReturnPattern(uword pc) : pc_(pc) {}
bool ReturnPattern::IsValid() const {
return *reinterpret_cast<uint16_t*>(pc_) == 0x8082;
}
bool PcRelativeCallPattern::IsValid() const {
Instr aupic(*reinterpret_cast<uint32_t*>(pc_));
if (aupic.opcode() != AUIPC) return false;
Instr jalr(*reinterpret_cast<uint32_t*>(pc_ + 4));
if (jalr.opcode() != JALR) return false;
if (aupic.rd() != jalr.rs1()) return false;
if (jalr.rd() != RA) return false;
return true;
}
bool PcRelativeTailCallPattern::IsValid() const {
Instr aupic(*reinterpret_cast<uint32_t*>(pc_));
if (aupic.opcode() != AUIPC) return false;
Instr jr(*reinterpret_cast<uint32_t*>(pc_ + 4));
if (jr.opcode() != JALR) return false;
if (aupic.rd() != jr.rs1()) return false;
if (jr.rd() != ZR) return false;
return true;
}
void PcRelativeTrampolineJumpPattern::Initialize() {
UNREACHABLE();
}
int32_t PcRelativeTrampolineJumpPattern::distance() {
UNREACHABLE();
return 0;
}
void PcRelativeTrampolineJumpPattern::set_distance(int32_t distance) {
UNREACHABLE();
}
bool PcRelativeTrampolineJumpPattern::IsValid() const {
UNREACHABLE();
return false;
}
intptr_t TypeTestingStubCallPattern::GetSubtypeTestCachePoolIndex() {
// Calls to the type testing stubs look like:
// lx s3, ...
// lx Rn, idx(pp)
// jalr s3
// where Rn = TypeTestABI::kSubtypeTestCacheReg.
// Ensure the caller of the type testing stub (whose return address is [pc_])
// branched via `blr R9` or a pc-relative call.
if (*reinterpret_cast<uint16_t*>(pc_ - 2) == 0x9982) { // jalr s3
// indirect call
// xxxx c.jalr s3
Register reg;
intptr_t pool_index = -1;
InstructionPattern::DecodeLoadWordFromPool(pc_ - 2, &reg, &pool_index);
ASSERT_EQUAL(reg, TypeTestABI::kSubtypeTestCacheReg);
return pool_index;
} else {
ASSERT(FLAG_precompiled_mode);
// pc-relative call
// xxxxxxxx aupic ra, hi
// xxxxxxxx jalr ra, lo
Instr jalr(*reinterpret_cast<uint32_t*>(pc_ - 4));
ASSERT(jalr.opcode() == JALR);
Instr auipc(*reinterpret_cast<uint32_t*>(pc_ - 8));
ASSERT(auipc.opcode() == AUIPC);
Register reg;
intptr_t pool_index = -1;
InstructionPattern::DecodeLoadWordFromPool(pc_ - 8, &reg, &pool_index);
ASSERT_EQUAL(reg, TypeTestABI::kSubtypeTestCacheReg);
return pool_index;
}
}
} // namespace dart
#endif // defined TARGET_ARCH_RISCV