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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/IonOptimizationLevels.h"
#include "jit/Ion.h"
#include "jit/JitHints.h"
#include "jit/JitRuntime.h"
#include "vm/JSScript.h"
#include "vm/JSScript-inl.h"
using namespace js;
using namespace js::jit;
namespace js {
namespace jit {
/*static*/
uint32_t OptimizationInfo::baseWarmUpThresholdForScript(JSContext* cx,
JSScript* script) {
// If an Ion counter hint is present, override the threshold.
if (cx->runtime()->jitRuntime()->hasJitHintsMap()) {
JitHintsMap* jitHints = cx->runtime()->jitRuntime()->getJitHintsMap();
uint32_t hintThreshold;
if (jitHints->getIonThresholdHint(script, hintThreshold)) {
return hintThreshold;
}
}
return JitOptions.normalIonWarmUpThreshold;
}
/*static*/
uint32_t OptimizationInfo::warmUpThresholdForPC(JSScript* script,
jsbytecode* pc,
uint32_t baseThreshold) {
MOZ_ASSERT(pc == nullptr || pc == script->code() ||
JSOp(*pc) == JSOp::LoopHead);
// The script must not start with a LoopHead op or the code below would be
MOZ_ASSERT_IF(pc && JSOp(*pc) == JSOp::LoopHead, pc > script->code());
uint32_t warmUpThreshold = baseThreshold;
if (pc == script->code()) {
pc = nullptr;
}
// If the script is too large to compile on the main thread, we can still
// compile it off thread. In these cases, increase the warm-up counter
// threshold to improve the compilation's type information and hopefully
// avoid later recompilation.
if (script->length() > JitOptions.ionMaxScriptSizeMainThread) {
warmUpThreshold *=
(script->length() / double(JitOptions.ionMaxScriptSizeMainThread));
}
uint32_t numLocalsAndArgs = NumLocalsAndArgs(script);
if (numLocalsAndArgs > JitOptions.ionMaxLocalsAndArgsMainThread) {
warmUpThreshold *=
(numLocalsAndArgs / double(JitOptions.ionMaxLocalsAndArgsMainThread));
}
if (!pc || JitOptions.eagerIonCompilation()) {
return warmUpThreshold;
}
// It's more efficient to enter outer loops, rather than inner loops, via OSR.
// To accomplish this, we use a slightly higher threshold for inner loops.
// Note that the loop depth is always > 0 so we will prefer non-OSR over OSR.
uint32_t loopDepth = LoopHeadDepthHint(pc);
MOZ_ASSERT(loopDepth > 0);
return warmUpThreshold + loopDepth * (baseThreshold / 10);
}
OptimizationLevel OptimizationLevelInfo::levelForScript(JSContext* cx,
JSScript* script,
jsbytecode* pc) const {
uint32_t baseThreshold =
OptimizationInfo::baseWarmUpThresholdForScript(cx, script);
if (script->getWarmUpCount() <
OptimizationInfo::warmUpThresholdForPC(script, pc, baseThreshold)) {
return OptimizationLevel::DontCompile;
}
return OptimizationLevel::Normal;
}
} // namespace jit
} // namespace js