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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:
* 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
#include "jit/JitContext.h"
#include "mozilla/Assertions.h"
#include "mozilla/ThreadLocal.h"
#include <stdlib.h>
#include "jit/CacheIRSpewer.h"
#include "jit/CompileWrappers.h"
#include "jit/Ion.h"
#include "jit/JitCode.h"
#include "jit/JitOptions.h"
#include "jit/JitSpewer.h"
#include "jit/MacroAssembler.h"
#include "jit/PerfSpewer.h"
#include "js/HeapAPI.h"
#include "vm/JSContext.h"
#ifdef JS_CODEGEN_ARM64
# include "jit/arm64/vixl/Cpu-vixl.h"
#endif
#if defined(ANDROID)
# include <sys/system_properties.h>
#endif
using namespace js;
using namespace js::jit;
namespace js::jit {
class TempAllocator;
}
// Assert that JitCode is gc::Cell aligned.
static_assert(sizeof(JitCode) % gc::CellAlignBytes == 0);
static MOZ_THREAD_LOCAL(JitContext*) TlsJitContext;
static JitContext* CurrentJitContext() {
if (!TlsJitContext.init()) {
return nullptr;
}
return TlsJitContext.get();
}
void jit::SetJitContext(JitContext* ctx) {
MOZ_ASSERT(!TlsJitContext.get());
TlsJitContext.set(ctx);
}
JitContext* jit::GetJitContext() {
MOZ_ASSERT(CurrentJitContext());
return CurrentJitContext();
}
JitContext* jit::MaybeGetJitContext() { return CurrentJitContext(); }
JitContext::JitContext(CompileRuntime* rt) : runtime(rt) {
MOZ_ASSERT(rt);
SetJitContext(this);
}
JitContext::JitContext(JSContext* cx)
: cx(cx), runtime(CompileRuntime::get(cx->runtime())) {
SetJitContext(this);
}
JitContext::JitContext() {
#ifdef DEBUG
isCompilingWasm_ = true;
#endif
SetJitContext(this);
}
JitContext::~JitContext() {
MOZ_ASSERT(TlsJitContext.get() == this);
TlsJitContext.set(nullptr);
}
bool jit::InitializeJit() {
if (!TlsJitContext.init()) {
return false;
}
CheckLogging();
#ifdef JS_CACHEIR_SPEW
const char* env = getenv("CACHEIR_LOGS");
if (env && env[0] && env[0] != '0') {
CacheIRSpewer::singleton().init(env);
}
#endif
#if defined(JS_CODEGEN_X86) || defined(JS_CODEGEN_X64)
// Compute flags.
js::jit::CPUInfo::ComputeFlags();
#endif
#if defined(JS_CODEGEN_ARM)
InitARMFlags();
#endif
#ifdef JS_CODEGEN_ARM64
// Initialize instruction cache flushing.
vixl::CPU::SetUp();
#endif
#ifndef JS_CODEGEN_NONE
MOZ_ASSERT(js::jit::CPUFlagsHaveBeenComputed());
#endif
// Note: jit flags need to be initialized after the InitARMFlags call above.
// This is the final point where we can set disableJitBackend = true, before
// we use this flag below with the HasJitBackend call.
if (!MacroAssembler::SupportsFloatingPoint()) {
JitOptions.disableJitBackend = true;
}
JitOptions.supportsUnalignedAccesses =
MacroAssembler::SupportsUnalignedAccesses();
if (HasJitBackend()) {
if (!InitProcessExecutableMemory()) {
return false;
}
}
PerfSpewer::Init();
return true;
}
void jit::ShutdownJit() {
if (HasJitBackend() && !JSRuntime::hasLiveRuntimes()) {
ReleaseProcessExecutableMemory();
}
}
bool jit::JitSupportsWasmSimd() {
#if defined(ENABLE_WASM_SIMD)
return js::jit::MacroAssembler::SupportsWasmSimd();
#else
return false;
#endif
}
bool jit::JitSupportsAtomics() {
#if defined(JS_CODEGEN_ARM)
// operations on ARM only when the CPU has byte, halfword, and
// doubleword load-exclusive and store-exclusive instructions,
// until we can add support for systems that don't have those.
return js::jit::HasLDSTREXBHD();
#else
return true;
#endif
}