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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ *
+ * Copyright 2016 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// This is an INTERNAL header for Wasm baseline compiler: definitions of
+// registers and the register allocator.
+
+#ifndef wasm_wasm_baseline_regdefs_h
+#define wasm_wasm_baseline_regdefs_h
+
+#include "wasm/WasmBCDefs.h"
+
+namespace js {
+namespace wasm {
+
+struct BaseCompiler;
+
+using namespace js::jit;
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Scratch register configuration.
+
+#if defined(JS_CODEGEN_NONE) || defined(JS_CODEGEN_WASM32)
+# define RABALDR_SCRATCH_I32
+# define RABALDR_SCRATCH_F32
+# define RABALDR_SCRATCH_F64
+
+static constexpr Register RabaldrScratchI32 = Register::Invalid();
+static constexpr FloatRegister RabaldrScratchF32 = InvalidFloatReg;
+static constexpr FloatRegister RabaldrScratchF64 = InvalidFloatReg;
+#endif
+
+#ifdef JS_CODEGEN_ARM64
+# define RABALDR_SCRATCH_I32
+# define RABALDR_SCRATCH_F32
+# define RABALDR_SCRATCH_F64
+# define RABALDR_SCRATCH_V128
+# define RABALDR_SCRATCH_F32_ALIASES_F64
+
+static constexpr Register RabaldrScratchI32{Registers::x15};
+
+// Note, the float scratch regs cannot be registers that are used for parameter
+// passing in any ABI we use. Argregs tend to be low-numbered; register 30
+// should be safe.
+
+static constexpr FloatRegister RabaldrScratchF32{FloatRegisters::s30,
+ FloatRegisters::Single};
+static constexpr FloatRegister RabaldrScratchF64{FloatRegisters::d30,
+ FloatRegisters::Double};
+# ifdef ENABLE_WASM_SIMD
+static constexpr FloatRegister RabaldrScratchV128{FloatRegisters::d30,
+ FloatRegisters::Simd128};
+# endif
+
+static_assert(RabaldrScratchF32 != ScratchFloat32Reg_, "Too busy");
+static_assert(RabaldrScratchF64 != ScratchDoubleReg_, "Too busy");
+# ifdef ENABLE_WASM_SIMD
+static_assert(RabaldrScratchV128 != ScratchSimd128Reg, "Too busy");
+# endif
+#endif
+
+#ifdef JS_CODEGEN_X86
+// The selection of EBX here steps gingerly around: the need for EDX
+// to be allocatable for multiply/divide; ECX to be allocatable for
+// shift/rotate; EAX (= ReturnReg) to be allocatable as the result
+// register; EBX not being one of the WasmTableCall registers; and
+// needing a temp register for load/store that has a single-byte
+// persona.
+//
+// The compiler assumes that RabaldrScratchI32 has a single-byte
+// persona. Code for 8-byte atomic operations assumes that
+// RabaldrScratchI32 is in fact ebx.
+
+# define RABALDR_SCRATCH_I32
+static constexpr Register RabaldrScratchI32 = ebx;
+#endif
+
+#ifdef JS_CODEGEN_ARM
+// We use our own scratch register, because the macro assembler uses
+// the regular scratch register(s) pretty liberally. We could
+// work around that in several cases but the mess does not seem
+// worth it yet. CallTempReg2 seems safe.
+
+# define RABALDR_SCRATCH_I32
+static constexpr Register RabaldrScratchI32 = CallTempReg2;
+#endif
+
+#ifdef JS_CODEGEN_MIPS64
+# define RABALDR_SCRATCH_I32
+static constexpr Register RabaldrScratchI32 = CallTempReg2;
+#endif
+
+#ifdef JS_CODEGEN_LOONG64
+// We use our own scratch register, because the macro assembler uses
+// the regular scratch register(s) pretty liberally. We could
+// work around that in several cases but the mess does not seem
+// worth it yet. CallTempReg2 seems safe.
+
+# define RABALDR_SCRATCH_I32
+static constexpr Register RabaldrScratchI32 = CallTempReg2;
+#endif
+
+#ifdef JS_CODEGEN_RISCV64
+# define RABALDR_SCRATCH_I32
+static constexpr Register RabaldrScratchI32 = CallTempReg2;
+#endif
+
+#ifdef RABALDR_SCRATCH_F32_ALIASES_F64
+# if !defined(RABALDR_SCRATCH_F32) || !defined(RABALDR_SCRATCH_F64)
+# error "Bad configuration"
+# endif
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// ...
+
+template <MIRType t>
+struct RegTypeOf {
+#ifdef ENABLE_WASM_SIMD
+ static_assert(t == MIRType::Float32 || t == MIRType::Double ||
+ t == MIRType::Simd128,
+ "Float mask type");
+#else
+ static_assert(t == MIRType::Float32 || t == MIRType::Double,
+ "Float mask type");
+#endif
+};
+
+template <>
+struct RegTypeOf<MIRType::Float32> {
+ static constexpr RegTypeName value = RegTypeName::Float32;
+};
+template <>
+struct RegTypeOf<MIRType::Double> {
+ static constexpr RegTypeName value = RegTypeName::Float64;
+};
+#ifdef ENABLE_WASM_SIMD
+template <>
+struct RegTypeOf<MIRType::Simd128> {
+ static constexpr RegTypeName value = RegTypeName::Vector128;
+};
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Strongly typed register wrappers.
+
+// The strongly typed register wrappers are especially useful to distinguish
+// float registers from double registers, but they also clearly distinguish
+// 32-bit registers from 64-bit register pairs on 32-bit systems.
+
+struct RegI32 : public Register {
+ RegI32() : Register(Register::Invalid()) {}
+ explicit RegI32(Register reg) : Register(reg) {
+ MOZ_ASSERT(reg != Invalid());
+ }
+ bool isInvalid() const { return *this == Invalid(); }
+ bool isValid() const { return !isInvalid(); }
+ static RegI32 Invalid() { return RegI32(); }
+};
+
+struct RegI64 : public Register64 {
+ RegI64() : Register64(Register64::Invalid()) {}
+ explicit RegI64(Register64 reg) : Register64(reg) {
+ MOZ_ASSERT(reg != Invalid());
+ }
+ bool isInvalid() const { return *this == Invalid(); }
+ bool isValid() const { return !isInvalid(); }
+ static RegI64 Invalid() { return RegI64(); }
+};
+
+// RegRef is for GC-pointers, for non GC-pointers use RegPtr
+struct RegRef : public Register {
+ RegRef() : Register(Register::Invalid()) {}
+ explicit RegRef(Register reg) : Register(reg) {
+ MOZ_ASSERT(reg != Invalid());
+ }
+ bool isInvalid() const { return *this == Invalid(); }
+ bool isValid() const { return !isInvalid(); }
+ static RegRef Invalid() { return RegRef(); }
+};
+
+// RegPtr is for non GC-pointers, for GC-pointers use RegRef
+struct RegPtr : public Register {
+ RegPtr() : Register(Register::Invalid()) {}
+ explicit RegPtr(Register reg) : Register(reg) {
+ MOZ_ASSERT(reg != Invalid());
+ }
+ bool isInvalid() const { return *this == Invalid(); }
+ bool isValid() const { return !isInvalid(); }
+ static RegPtr Invalid() { return RegPtr(); }
+};
+
+struct RegF32 : public FloatRegister {
+ RegF32() {}
+ explicit RegF32(FloatRegister reg) : FloatRegister(reg) {
+ MOZ_ASSERT(isSingle());
+ }
+ bool isValid() const { return !isInvalid(); }
+ static RegF32 Invalid() { return RegF32(); }
+};
+
+struct RegF64 : public FloatRegister {
+ RegF64() {}
+ explicit RegF64(FloatRegister reg) : FloatRegister(reg) {
+ MOZ_ASSERT(isDouble());
+ }
+ bool isValid() const { return !isInvalid(); }
+ static RegF64 Invalid() { return RegF64(); }
+};
+
+#ifdef ENABLE_WASM_SIMD
+struct RegV128 : public FloatRegister {
+ RegV128() {}
+ explicit RegV128(FloatRegister reg) : FloatRegister(reg) {
+ MOZ_ASSERT(isSimd128());
+ }
+ bool isValid() const { return !isInvalid(); }
+ static RegV128 Invalid() { return RegV128(); }
+};
+#endif
+
+struct AnyReg {
+ union {
+ RegI32 i32_;
+ RegI64 i64_;
+ RegRef ref_;
+ RegF32 f32_;
+ RegF64 f64_;
+#ifdef ENABLE_WASM_SIMD
+ RegV128 v128_;
+#endif
+ };
+
+ enum {
+ I32,
+ I64,
+ REF,
+ F32,
+ F64,
+#ifdef ENABLE_WASM_SIMD
+ V128
+#endif
+ } tag;
+
+ explicit AnyReg(RegI32 r) {
+ tag = I32;
+ i32_ = r;
+ }
+ explicit AnyReg(RegI64 r) {
+ tag = I64;
+ i64_ = r;
+ }
+ explicit AnyReg(RegF32 r) {
+ tag = F32;
+ f32_ = r;
+ }
+ explicit AnyReg(RegF64 r) {
+ tag = F64;
+ f64_ = r;
+ }
+#ifdef ENABLE_WASM_SIMD
+ explicit AnyReg(RegV128 r) {
+ tag = V128;
+ v128_ = r;
+ }
+#endif
+ explicit AnyReg(RegRef r) {
+ tag = REF;
+ ref_ = r;
+ }
+
+ RegI32 i32() const {
+ MOZ_ASSERT(tag == I32);
+ return i32_;
+ }
+ RegI64 i64() const {
+ MOZ_ASSERT(tag == I64);
+ return i64_;
+ }
+ RegF32 f32() const {
+ MOZ_ASSERT(tag == F32);
+ return f32_;
+ }
+ RegF64 f64() const {
+ MOZ_ASSERT(tag == F64);
+ return f64_;
+ }
+#ifdef ENABLE_WASM_SIMD
+ RegV128 v128() const {
+ MOZ_ASSERT(tag == V128);
+ return v128_;
+ }
+#endif
+ RegRef ref() const {
+ MOZ_ASSERT(tag == REF);
+ return ref_;
+ }
+
+ AnyRegister any() const {
+ switch (tag) {
+ case F32:
+ return AnyRegister(f32_);
+ case F64:
+ return AnyRegister(f64_);
+#ifdef ENABLE_WASM_SIMD
+ case V128:
+ return AnyRegister(v128_);
+#endif
+ case I32:
+ return AnyRegister(i32_);
+ case I64:
+#ifdef JS_PUNBOX64
+ return AnyRegister(i64_.reg);
+#else
+ // The compiler is written so that this is never needed: any() is
+ // called on arbitrary registers for asm.js but asm.js does not have
+ // 64-bit ints. For wasm, any() is called on arbitrary registers
+ // only on 64-bit platforms.
+ MOZ_CRASH("AnyReg::any() on 32-bit platform");
+#endif
+ case REF:
+ MOZ_CRASH("AnyReg::any() not implemented for ref types");
+ default:
+ MOZ_CRASH();
+ }
+ // Work around GCC 5 analysis/warning bug.
+ MOZ_CRASH("AnyReg::any(): impossible case");
+ }
+};
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Platform-specific registers.
+//
+// All platforms must define struct SpecificRegs. All 32-bit platforms must
+// have an abiReturnRegI64 member in that struct.
+
+#if defined(JS_CODEGEN_X64)
+struct SpecificRegs {
+ RegI32 eax, ecx, edx, edi, esi;
+ RegI64 rax, rcx, rdx;
+
+ SpecificRegs()
+ : eax(RegI32(js::jit::eax)),
+ ecx(RegI32(js::jit::ecx)),
+ edx(RegI32(js::jit::edx)),
+ edi(RegI32(js::jit::edi)),
+ esi(RegI32(js::jit::esi)),
+ rax(RegI64(Register64(js::jit::rax))),
+ rcx(RegI64(Register64(js::jit::rcx))),
+ rdx(RegI64(Register64(js::jit::rdx))) {}
+};
+#elif defined(JS_CODEGEN_X86)
+struct SpecificRegs {
+ RegI32 eax, ecx, edx, edi, esi;
+ RegI64 ecx_ebx, edx_eax, abiReturnRegI64;
+
+ SpecificRegs()
+ : eax(RegI32(js::jit::eax)),
+ ecx(RegI32(js::jit::ecx)),
+ edx(RegI32(js::jit::edx)),
+ edi(RegI32(js::jit::edi)),
+ esi(RegI32(js::jit::esi)),
+ ecx_ebx(RegI64(Register64(js::jit::ecx, js::jit::ebx))),
+ edx_eax(RegI64(Register64(js::jit::edx, js::jit::eax))),
+ abiReturnRegI64(edx_eax) {}
+};
+#elif defined(JS_CODEGEN_ARM)
+struct SpecificRegs {
+ RegI64 abiReturnRegI64;
+
+ SpecificRegs() : abiReturnRegI64(ReturnReg64) {}
+};
+#elif defined(JS_CODEGEN_ARM64) || defined(JS_CODEGEN_MIPS64) || \
+ defined(JS_CODEGEN_LOONG64) || defined(JS_CODEGEN_RISCV64)
+struct SpecificRegs {
+ // Required by gcc.
+ SpecificRegs() {}
+};
+#else
+struct SpecificRegs {
+# ifndef JS_64BIT
+ RegI64 abiReturnRegI64;
+# endif
+
+ SpecificRegs() { MOZ_CRASH("BaseCompiler porting interface: SpecificRegs"); }
+};
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Register allocator.
+
+class BaseRegAlloc {
+ // Notes on float register allocation.
+ //
+ // The general rule in SpiderMonkey is that float registers can alias double
+ // registers, but there are predicates to handle exceptions to that rule:
+ // hasUnaliasedDouble() and hasMultiAlias(). The way aliasing actually
+ // works is platform dependent and exposed through the aliased(n, &r)
+ // predicate, etc.
+ //
+ // - hasUnaliasedDouble(): on ARM VFPv3-D32 there are double registers that
+ // cannot be treated as float.
+ // - hasMultiAlias(): on ARM and MIPS a double register aliases two float
+ // registers.
+ //
+ // On some platforms (x86, x64, ARM64) but not all (ARM)
+ // ScratchFloat32Register is the same as ScratchDoubleRegister.
+ //
+ // It's a basic invariant of the AllocatableRegisterSet that it deals
+ // properly with aliasing of registers: if s0 or s1 are allocated then d0 is
+ // not allocatable; if s0 and s1 are freed individually then d0 becomes
+ // allocatable.
+
+ BaseCompiler* bc;
+ AllocatableGeneralRegisterSet availGPR;
+ AllocatableFloatRegisterSet availFPU;
+#ifdef DEBUG
+ // The registers available after removing ScratchReg, HeapReg, etc.
+ AllocatableGeneralRegisterSet allGPR;
+ AllocatableFloatRegisterSet allFPU;
+ uint32_t scratchTaken;
+#endif
+#ifdef JS_CODEGEN_X86
+ AllocatableGeneralRegisterSet singleByteRegs;
+#endif
+
+ bool hasGPR() { return !availGPR.empty(); }
+
+ bool hasGPR64() {
+#ifdef JS_PUNBOX64
+ return !availGPR.empty();
+#else
+ if (availGPR.empty()) {
+ return false;
+ }
+ Register r = allocGPR();
+ bool available = !availGPR.empty();
+ freeGPR(r);
+ return available;
+#endif
+ }
+
+ template <MIRType t>
+ bool hasFPU() {
+ return availFPU.hasAny<RegTypeOf<t>::value>();
+ }
+
+ bool isAvailableGPR(Register r) { return availGPR.has(r); }
+
+ bool isAvailableFPU(FloatRegister r) { return availFPU.has(r); }
+
+ void allocGPR(Register r) {
+ MOZ_ASSERT(isAvailableGPR(r));
+ availGPR.take(r);
+ }
+
+ Register allocGPR() {
+ MOZ_ASSERT(hasGPR());
+ return availGPR.takeAny();
+ }
+
+ void allocInt64(Register64 r) {
+#ifdef JS_PUNBOX64
+ allocGPR(r.reg);
+#else
+ allocGPR(r.low);
+ allocGPR(r.high);
+#endif
+ }
+
+ Register64 allocInt64() {
+ MOZ_ASSERT(hasGPR64());
+#ifdef JS_PUNBOX64
+ return Register64(availGPR.takeAny());
+#else
+ Register high = availGPR.takeAny();
+ Register low = availGPR.takeAny();
+ return Register64(high, low);
+#endif
+ }
+
+#ifdef JS_CODEGEN_ARM
+ // r12 is normally the ScratchRegister and r13 is always the stack pointer,
+ // so the highest possible pair has r10 as the even-numbered register.
+
+ static constexpr uint32_t PAIR_LIMIT = 10;
+
+ bool hasGPRPair() {
+ for (uint32_t i = 0; i <= PAIR_LIMIT; i += 2) {
+ if (isAvailableGPR(Register::FromCode(i)) &&
+ isAvailableGPR(Register::FromCode(i + 1))) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ void allocGPRPair(Register* low, Register* high) {
+ MOZ_ASSERT(hasGPRPair());
+ for (uint32_t i = 0; i <= PAIR_LIMIT; i += 2) {
+ if (isAvailableGPR(Register::FromCode(i)) &&
+ isAvailableGPR(Register::FromCode(i + 1))) {
+ *low = Register::FromCode(i);
+ *high = Register::FromCode(i + 1);
+ allocGPR(*low);
+ allocGPR(*high);
+ return;
+ }
+ }
+ MOZ_CRASH("No pair");
+ }
+#endif
+
+ void allocFPU(FloatRegister r) {
+ MOZ_ASSERT(isAvailableFPU(r));
+ availFPU.take(r);
+ }
+
+ template <MIRType t>
+ FloatRegister allocFPU() {
+ return availFPU.takeAny<RegTypeOf<t>::value>();
+ }
+
+ void freeGPR(Register r) { availGPR.add(r); }
+
+ void freeInt64(Register64 r) {
+#ifdef JS_PUNBOX64
+ freeGPR(r.reg);
+#else
+ freeGPR(r.low);
+ freeGPR(r.high);
+#endif
+ }
+
+ void freeFPU(FloatRegister r) { availFPU.add(r); }
+
+ public:
+ explicit BaseRegAlloc()
+ : bc(nullptr),
+ availGPR(GeneralRegisterSet::All()),
+ availFPU(FloatRegisterSet::All())
+#ifdef DEBUG
+ ,
+ scratchTaken(0)
+#endif
+#ifdef JS_CODEGEN_X86
+ ,
+ singleByteRegs(GeneralRegisterSet(Registers::SingleByteRegs))
+#endif
+ {
+ RegisterAllocator::takeWasmRegisters(availGPR);
+
+#ifdef RABALDR_PIN_INSTANCE
+ // If the InstanceReg is pinned then it is never available for
+ // allocation.
+ availGPR.take(InstanceReg);
+#endif
+
+ // Allocate any private scratch registers.
+#if defined(RABALDR_SCRATCH_I32)
+ if (RabaldrScratchI32 != RegI32::Invalid()) {
+ availGPR.take(RabaldrScratchI32);
+ }
+#endif
+
+#ifdef RABALDR_SCRATCH_F32_ALIASES_F64
+ static_assert(RabaldrScratchF32 != InvalidFloatReg, "Float reg definition");
+ static_assert(RabaldrScratchF64 != InvalidFloatReg, "Float reg definition");
+#endif
+
+#if defined(RABALDR_SCRATCH_F32) && !defined(RABALDR_SCRATCH_F32_ALIASES_F64)
+ if (RabaldrScratchF32 != RegF32::Invalid()) {
+ availFPU.take(RabaldrScratchF32);
+ }
+#endif
+
+#if defined(RABALDR_SCRATCH_F64)
+# ifdef RABALDR_SCRATCH_F32_ALIASES_F64
+ MOZ_ASSERT(availFPU.has(RabaldrScratchF32));
+# endif
+ if (RabaldrScratchF64 != RegF64::Invalid()) {
+ availFPU.take(RabaldrScratchF64);
+ }
+# ifdef RABALDR_SCRATCH_F32_ALIASES_F64
+ MOZ_ASSERT(!availFPU.has(RabaldrScratchF32));
+# endif
+#endif
+
+#ifdef DEBUG
+ allGPR = availGPR;
+ allFPU = availFPU;
+#endif
+ }
+
+ void init(BaseCompiler* bc) { this->bc = bc; }
+
+ enum class ScratchKind { I32 = 1, F32 = 2, F64 = 4, V128 = 8 };
+
+#ifdef DEBUG
+ bool isScratchRegisterTaken(ScratchKind s) const {
+ return (scratchTaken & uint32_t(s)) != 0;
+ }
+
+ void setScratchRegisterTaken(ScratchKind s, bool state) {
+ if (state) {
+ scratchTaken |= uint32_t(s);
+ } else {
+ scratchTaken &= ~uint32_t(s);
+ }
+ }
+#endif
+
+#ifdef JS_CODEGEN_X86
+ bool isSingleByteI32(Register r) { return singleByteRegs.has(r); }
+#endif
+
+ bool isAvailableI32(RegI32 r) { return isAvailableGPR(r); }
+
+ bool isAvailableI64(RegI64 r) {
+#ifdef JS_PUNBOX64
+ return isAvailableGPR(r.reg);
+#else
+ return isAvailableGPR(r.low) && isAvailableGPR(r.high);
+#endif
+ }
+
+ bool isAvailableRef(RegRef r) { return isAvailableGPR(r); }
+
+ bool isAvailablePtr(RegPtr r) { return isAvailableGPR(r); }
+
+ bool isAvailableF32(RegF32 r) { return isAvailableFPU(r); }
+
+ bool isAvailableF64(RegF64 r) { return isAvailableFPU(r); }
+
+#ifdef ENABLE_WASM_SIMD
+ bool isAvailableV128(RegV128 r) { return isAvailableFPU(r); }
+#endif
+
+ [[nodiscard]] inline RegI32 needI32();
+ inline void needI32(RegI32 specific);
+
+ [[nodiscard]] inline RegI64 needI64();
+ inline void needI64(RegI64 specific);
+
+ [[nodiscard]] inline RegRef needRef();
+ inline void needRef(RegRef specific);
+
+ [[nodiscard]] inline RegPtr needPtr();
+ inline void needPtr(RegPtr specific);
+
+ [[nodiscard]] inline RegF32 needF32();
+ inline void needF32(RegF32 specific);
+
+ [[nodiscard]] inline RegF64 needF64();
+ inline void needF64(RegF64 specific);
+
+#ifdef ENABLE_WASM_SIMD
+ [[nodiscard]] inline RegV128 needV128();
+ inline void needV128(RegV128 specific);
+#endif
+
+ inline void freeI32(RegI32 r);
+ inline void freeI64(RegI64 r);
+ inline void freeRef(RegRef r);
+ inline void freePtr(RegPtr r);
+ inline void freeF64(RegF64 r);
+ inline void freeF32(RegF32 r);
+#ifdef ENABLE_WASM_SIMD
+ inline void freeV128(RegV128 r);
+#endif
+
+ // Use when you need a register for a short time but explicitly want to avoid
+ // a full sync().
+ [[nodiscard]] inline RegPtr needTempPtr(RegPtr fallback, bool* saved);
+ inline void freeTempPtr(RegPtr r, bool saved);
+
+#ifdef JS_CODEGEN_ARM
+ [[nodiscard]] inline RegI64 needI64Pair();
+#endif
+
+#ifdef DEBUG
+ friend class LeakCheck;
+
+ class MOZ_RAII LeakCheck {
+ private:
+ const BaseRegAlloc& ra;
+ AllocatableGeneralRegisterSet knownGPR_;
+ AllocatableFloatRegisterSet knownFPU_;
+
+ public:
+ explicit LeakCheck(const BaseRegAlloc& ra) : ra(ra) {
+ knownGPR_ = ra.availGPR;
+ knownFPU_ = ra.availFPU;
+ }
+
+ ~LeakCheck() {
+ MOZ_ASSERT(knownGPR_.bits() == ra.allGPR.bits());
+ MOZ_ASSERT(knownFPU_.bits() == ra.allFPU.bits());
+ }
+
+ void addKnownI32(RegI32 r) { knownGPR_.add(r); }
+
+ void addKnownI64(RegI64 r) {
+# ifdef JS_PUNBOX64
+ knownGPR_.add(r.reg);
+# else
+ knownGPR_.add(r.high);
+ knownGPR_.add(r.low);
+# endif
+ }
+
+ void addKnownF32(RegF32 r) { knownFPU_.add(r); }
+
+ void addKnownF64(RegF64 r) { knownFPU_.add(r); }
+
+# ifdef ENABLE_WASM_SIMD
+ void addKnownV128(RegV128 r) { knownFPU_.add(r); }
+# endif
+
+ void addKnownRef(RegRef r) { knownGPR_.add(r); }
+ };
+#endif
+};
+
+// Scratch register abstractions.
+//
+// We define our own scratch registers when the platform doesn't provide what we
+// need. A notable use case is that we will need a private scratch register
+// when the platform masm uses its scratch register very frequently (eg, ARM).
+
+class BaseScratchRegister {
+#ifdef DEBUG
+ BaseRegAlloc& ra;
+ BaseRegAlloc::ScratchKind kind_;
+
+ public:
+ explicit BaseScratchRegister(BaseRegAlloc& ra, BaseRegAlloc::ScratchKind kind)
+ : ra(ra), kind_(kind) {
+ MOZ_ASSERT(!ra.isScratchRegisterTaken(kind_));
+ ra.setScratchRegisterTaken(kind_, true);
+ }
+ ~BaseScratchRegister() {
+ MOZ_ASSERT(ra.isScratchRegisterTaken(kind_));
+ ra.setScratchRegisterTaken(kind_, false);
+ }
+#else
+ public:
+ explicit BaseScratchRegister(BaseRegAlloc& ra,
+ BaseRegAlloc::ScratchKind kind) {}
+#endif
+};
+
+#ifdef ENABLE_WASM_SIMD
+# ifdef RABALDR_SCRATCH_V128
+class ScratchV128 : public BaseScratchRegister {
+ public:
+ explicit ScratchV128(BaseRegAlloc& ra)
+ : BaseScratchRegister(ra, BaseRegAlloc::ScratchKind::V128) {}
+ operator RegV128() const { return RegV128(RabaldrScratchV128); }
+};
+# else
+class ScratchV128 : public ScratchSimd128Scope {
+ public:
+ explicit ScratchV128(MacroAssembler& m) : ScratchSimd128Scope(m) {}
+ operator RegV128() const { return RegV128(FloatRegister(*this)); }
+};
+# endif
+#endif
+
+#ifdef RABALDR_SCRATCH_F64
+class ScratchF64 : public BaseScratchRegister {
+ public:
+ explicit ScratchF64(BaseRegAlloc& ra)
+ : BaseScratchRegister(ra, BaseRegAlloc::ScratchKind::F64) {}
+ operator RegF64() const { return RegF64(RabaldrScratchF64); }
+};
+#else
+class ScratchF64 : public ScratchDoubleScope {
+ public:
+ explicit ScratchF64(MacroAssembler& m) : ScratchDoubleScope(m) {}
+ operator RegF64() const { return RegF64(FloatRegister(*this)); }
+};
+#endif
+
+#ifdef RABALDR_SCRATCH_F32
+class ScratchF32 : public BaseScratchRegister {
+ public:
+ explicit ScratchF32(BaseRegAlloc& ra)
+ : BaseScratchRegister(ra, BaseRegAlloc::ScratchKind::F32) {}
+ operator RegF32() const { return RegF32(RabaldrScratchF32); }
+};
+#else
+class ScratchF32 : public ScratchFloat32Scope {
+ public:
+ explicit ScratchF32(MacroAssembler& m) : ScratchFloat32Scope(m) {}
+ operator RegF32() const { return RegF32(FloatRegister(*this)); }
+};
+#endif
+
+#ifdef RABALDR_SCRATCH_I32
+template <class RegType>
+class ScratchGPR : public BaseScratchRegister {
+ public:
+ explicit ScratchGPR(BaseRegAlloc& ra)
+ : BaseScratchRegister(ra, BaseRegAlloc::ScratchKind::I32) {}
+ operator RegType() const { return RegType(RabaldrScratchI32); }
+};
+#else
+template <class RegType>
+class ScratchGPR : public ScratchRegisterScope {
+ public:
+ explicit ScratchGPR(MacroAssembler& m) : ScratchRegisterScope(m) {}
+ operator RegType() const { return RegType(Register(*this)); }
+};
+#endif
+
+using ScratchI32 = ScratchGPR<RegI32>;
+using ScratchPtr = ScratchGPR<RegPtr>;
+using ScratchRef = ScratchGPR<RegRef>;
+
+#if defined(JS_CODEGEN_X86)
+// ScratchEBX is a mnemonic device: For some atomic ops we really need EBX,
+// no other register will do. And we would normally have to allocate that
+// register using ScratchI32 since normally the scratch register is EBX.
+// But the whole point of ScratchI32 is to hide that relationship. By using
+// the ScratchEBX alias, we document that at that point we require the
+// scratch register to be EBX.
+using ScratchEBX = ScratchI32;
+
+// ScratchI8 is a mnemonic device: For some ops we need a register with a
+// byte subregister.
+using ScratchI8 = ScratchI32;
+#endif
+
+} // namespace wasm
+} // namespace js
+
+#endif // wasm_wasm_baseline_regdefs_h