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// AsmJit - Machine code generation for C++
//
// * Official AsmJit Home Page: https://asmjit.com
// * Official Github Repository: https://github.com/asmjit/asmjit
//
// Copyright (c) 2008-2020 The AsmJit Authors
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
#include "../core/api-build_p.h"
#ifndef ASMJIT_NO_COMPILER
#include "../core/formatter.h"
#include "../core/ralocal_p.h"
#include "../core/rapass_p.h"
#include "../core/support.h"
#include "../core/type.h"
#include "../core/zonestack.h"
ASMJIT_BEGIN_NAMESPACE
// ============================================================================
// [asmjit::RABlock - Control Flow]
// ============================================================================
Error RABlock::appendSuccessor(RABlock* successor) noexcept {
RABlock* predecessor = this;
if (predecessor->_successors.contains(successor))
return kErrorOk;
ASMJIT_ASSERT(!successor->_predecessors.contains(predecessor));
ASMJIT_PROPAGATE(successor->_predecessors.willGrow(allocator()));
ASMJIT_PROPAGATE(predecessor->_successors.willGrow(allocator()));
predecessor->_successors.appendUnsafe(successor);
successor->_predecessors.appendUnsafe(predecessor);
return kErrorOk;
}
Error RABlock::prependSuccessor(RABlock* successor) noexcept {
RABlock* predecessor = this;
if (predecessor->_successors.contains(successor))
return kErrorOk;
ASMJIT_ASSERT(!successor->_predecessors.contains(predecessor));
ASMJIT_PROPAGATE(successor->_predecessors.willGrow(allocator()));
ASMJIT_PROPAGATE(predecessor->_successors.willGrow(allocator()));
predecessor->_successors.prependUnsafe(successor);
successor->_predecessors.prependUnsafe(predecessor);
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Construction / Destruction]
// ============================================================================
BaseRAPass::BaseRAPass() noexcept : FuncPass("BaseRAPass") {}
BaseRAPass::~BaseRAPass() noexcept {}
// ============================================================================
// [asmjit::BaseRAPass - RunOnFunction]
// ============================================================================
static void RAPass_reset(BaseRAPass* self, FuncDetail* funcDetail) noexcept {
ZoneAllocator* allocator = self->allocator();
self->_blocks.reset();
self->_exits.reset();
self->_pov.reset();
self->_workRegs.reset();
self->_instructionCount = 0;
self->_createdBlockCount = 0;
self->_sharedAssignments.reset();
self->_lastTimestamp = 0;
self->_archTraits = nullptr;
self->_physRegIndex.reset();
self->_physRegCount.reset();
self->_physRegTotal = 0;
for (size_t i = 0; i < ASMJIT_ARRAY_SIZE(self->_scratchRegIndexes); i++)
self->_scratchRegIndexes[i] = BaseReg::kIdBad;
self->_availableRegs.reset();
self->_availableRegCount.reset();
self->_clobberedRegs.reset();
self->_workRegs.reset();
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++) {
self->_workRegsOfGroup[group].reset();
self->_strategy[group].reset();
self->_globalLiveSpans[group] = nullptr;
}
self->_globalMaxLiveCount.reset();
self->_temporaryMem.reset();
self->_stackAllocator.reset(allocator);
self->_argsAssignment.reset(funcDetail);
self->_numStackArgsToStackSlots = 0;
self->_maxWorkRegNameSize = 0;
}
static void RAPass_resetVirtRegData(BaseRAPass* self) noexcept {
// Zero everything so it cannot be used by accident.
for (RAWorkReg* wReg : self->_workRegs) {
VirtReg* vReg = wReg->virtReg();
vReg->_workReg = nullptr;
}
}
Error BaseRAPass::runOnFunction(Zone* zone, Logger* logger, FuncNode* func) {
_allocator.reset(zone);
#ifndef ASMJIT_NO_LOGGING
_logger = logger;
_debugLogger = nullptr;
if (logger) {
_loggerFlags = logger->flags();
if (_loggerFlags & FormatOptions::kFlagDebugPasses)
_debugLogger = logger;
}
#else
DebugUtils::unused(logger);
#endif
// Initialize all core structures to use `zone` and `func`.
BaseNode* end = func->endNode();
_func = func;
_stop = end->next();
_extraBlock = end;
RAPass_reset(this, &_func->_funcDetail);
// Initialize architecture-specific members.
onInit();
// Perform all allocation steps required.
Error err = onPerformAllSteps();
// Must be called regardless of the allocation status.
onDone();
// Reset possible connections introduced by the register allocator.
RAPass_resetVirtRegData(this);
// Reset all core structures and everything that depends on the passed `Zone`.
RAPass_reset(this, nullptr);
_allocator.reset(nullptr);
#ifndef ASMJIT_NO_LOGGING
_logger = nullptr;
_debugLogger = nullptr;
_loggerFlags = 0;
#endif
_func = nullptr;
_stop = nullptr;
_extraBlock = nullptr;
// Reset `Zone` as nothing should persist between `runOnFunction()` calls.
zone->reset();
// We alter the compiler cursor, because it doesn't make sense to reference
// it after the compilation - some nodes may disappear and the old cursor
// can go out anyway.
cc()->_setCursor(cc()->lastNode());
return err;
}
Error BaseRAPass::onPerformAllSteps() noexcept {
ASMJIT_PROPAGATE(buildCFG());
ASMJIT_PROPAGATE(buildViews());
ASMJIT_PROPAGATE(removeUnreachableBlocks());
ASMJIT_PROPAGATE(buildDominators());
ASMJIT_PROPAGATE(buildLiveness());
ASMJIT_PROPAGATE(assignArgIndexToWorkRegs());
#ifndef ASMJIT_NO_LOGGING
if (logger() && logger()->hasFlag(FormatOptions::kFlagAnnotations))
ASMJIT_PROPAGATE(annotateCode());
#endif
ASMJIT_PROPAGATE(runGlobalAllocator());
ASMJIT_PROPAGATE(runLocalAllocator());
ASMJIT_PROPAGATE(updateStackFrame());
ASMJIT_PROPAGATE(insertPrologEpilog());
ASMJIT_PROPAGATE(rewrite());
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - CFG - Basic Block Management]
// ============================================================================
RABlock* BaseRAPass::newBlock(BaseNode* initialNode) noexcept {
RABlock* block = zone()->newT<RABlock>(this);
if (ASMJIT_UNLIKELY(!block))
return nullptr;
block->setFirst(initialNode);
block->setLast(initialNode);
_createdBlockCount++;
return block;
}
RABlock* BaseRAPass::newBlockOrExistingAt(LabelNode* cbLabel, BaseNode** stoppedAt) noexcept {
if (cbLabel->hasPassData())
return cbLabel->passData<RABlock>();
FuncNode* func = this->func();
BaseNode* node = cbLabel->prev();
RABlock* block = nullptr;
// Try to find some label, but terminate the loop on any code. We try hard to
// coalesce code that contains two consecutive labels or a combination of
// non-code nodes between 2 or more labels.
//
// Possible cases that would share the same basic block:
//
// 1. Two or more consecutive labels:
// Label1:
// Label2:
//
// 2. Two or more labels separated by non-code nodes:
// Label1:
// ; Some comment...
// .align 16
// Label2:
size_t nPendingLabels = 0;
while (node) {
if (node->type() == BaseNode::kNodeLabel) {
// Function has a different NodeType, just make sure this was not messed
// up as we must never associate BasicBlock with a `func` itself.
ASMJIT_ASSERT(node != func);
block = node->passData<RABlock>();
if (block) {
// Exit node has always a block associated with it. If we went here it
// means that `cbLabel` passed here is after the end of the function
// and cannot be merged with the function exit block.
if (node == func->exitNode())
block = nullptr;
break;
}
nPendingLabels++;
}
else if (node->type() == BaseNode::kNodeAlign) {
// Align node is fine.
}
else {
break;
}
node = node->prev();
}
if (stoppedAt)
*stoppedAt = node;
if (!block) {
block = newBlock();
if (ASMJIT_UNLIKELY(!block))
return nullptr;
}
cbLabel->setPassData<RABlock>(block);
node = cbLabel;
while (nPendingLabels) {
node = node->prev();
for (;;) {
if (node->type() == BaseNode::kNodeLabel) {
node->setPassData<RABlock>(block);
nPendingLabels--;
break;
}
node = node->prev();
ASMJIT_ASSERT(node != nullptr);
}
}
if (!block->first()) {
block->setFirst(node);
block->setLast(cbLabel);
}
return block;
}
Error BaseRAPass::addBlock(RABlock* block) noexcept {
ASMJIT_PROPAGATE(_blocks.willGrow(allocator()));
block->_blockId = blockCount();
_blocks.appendUnsafe(block);
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - CFG - Build]
// ============================================================================
Error BaseRAPass::initSharedAssignments(const ZoneVector<uint32_t>& sharedAssignmentsMap) noexcept {
if (sharedAssignmentsMap.empty())
return kErrorOk;
uint32_t count = 0;
for (RABlock* block : _blocks) {
if (block->hasSharedAssignmentId()) {
uint32_t sharedAssignmentId = sharedAssignmentsMap[block->sharedAssignmentId()];
block->setSharedAssignmentId(sharedAssignmentId);
count = Support::max(count, sharedAssignmentId + 1);
}
}
ASMJIT_PROPAGATE(_sharedAssignments.resize(allocator(), count));
// Aggregate all entry scratch GP regs from blocks of the same assignment to
// the assignment itself. It will then be used instead of RABlock's own scratch
// regs mask, as shared assignments have precedence.
for (RABlock* block : _blocks) {
if (block->hasJumpTable()) {
const RABlocks& successors = block->successors();
if (!successors.empty()) {
RABlock* firstSuccessor = successors[0];
// NOTE: Shared assignments connect all possible successors so we only
// need the first to propagate exit scratch gp registers.
ASMJIT_ASSERT(firstSuccessor->hasSharedAssignmentId());
RASharedAssignment& sa = _sharedAssignments[firstSuccessor->sharedAssignmentId()];
sa.addEntryScratchGpRegs(block->exitScratchGpRegs());
}
}
if (block->hasSharedAssignmentId()) {
RASharedAssignment& sa = _sharedAssignments[block->sharedAssignmentId()];
sa.addEntryScratchGpRegs(block->_entryScratchGpRegs);
}
}
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - CFG - Views Order]
// ============================================================================
class RABlockVisitItem {
public:
inline RABlockVisitItem(RABlock* block, uint32_t index) noexcept
: _block(block),
_index(index) {}
inline RABlockVisitItem(const RABlockVisitItem& other) noexcept
: _block(other._block),
_index(other._index) {}
inline RABlockVisitItem& operator=(const RABlockVisitItem& other) noexcept = default;
inline RABlock* block() const noexcept { return _block; }
inline uint32_t index() const noexcept { return _index; }
RABlock* _block;
uint32_t _index;
};
Error BaseRAPass::buildViews() noexcept {
#ifndef ASMJIT_NO_LOGGING
Logger* logger = debugLogger();
ASMJIT_RA_LOG_FORMAT("[RAPass::BuildViews]\n");
#endif
uint32_t count = blockCount();
if (ASMJIT_UNLIKELY(!count)) return kErrorOk;
ASMJIT_PROPAGATE(_pov.reserve(allocator(), count));
ZoneStack<RABlockVisitItem> stack;
ASMJIT_PROPAGATE(stack.init(allocator()));
ZoneBitVector visited;
ASMJIT_PROPAGATE(visited.resize(allocator(), count));
RABlock* current = _blocks[0];
uint32_t i = 0;
for (;;) {
for (;;) {
if (i >= current->successors().size())
break;
// Skip if already visited.
RABlock* child = current->successors()[i++];
if (visited.bitAt(child->blockId()))
continue;
// Mark as visited to prevent visiting the same block multiple times.
visited.setBit(child->blockId(), true);
// Add the current block on the stack, we will get back to it later.
ASMJIT_PROPAGATE(stack.append(RABlockVisitItem(current, i)));
current = child;
i = 0;
}
current->makeReachable();
current->_povOrder = _pov.size();
_pov.appendUnsafe(current);
if (stack.empty())
break;
RABlockVisitItem top = stack.pop();
current = top.block();
i = top.index();
}
ASMJIT_RA_LOG_COMPLEX({
StringTmp<1024> sb;
for (RABlock* block : blocks()) {
sb.clear();
if (block->hasSuccessors()) {
sb.appendFormat(" #%u -> {", block->blockId());
_dumpBlockIds(sb, block->successors());
sb.append("}\n");
}
else {
sb.appendFormat(" #%u -> {Exit}\n", block->blockId());
}
logger->log(sb);
}
});
visited.release(allocator());
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - CFG - Dominators]
// ============================================================================
static ASMJIT_INLINE RABlock* intersectBlocks(RABlock* b1, RABlock* b2) noexcept {
while (b1 != b2) {
while (b2->povOrder() > b1->povOrder()) b1 = b1->iDom();
while (b1->povOrder() > b2->povOrder()) b2 = b2->iDom();
}
return b1;
}
// Based on "A Simple, Fast Dominance Algorithm".
Error BaseRAPass::buildDominators() noexcept {
#ifndef ASMJIT_NO_LOGGING
Logger* logger = debugLogger();
ASMJIT_RA_LOG_FORMAT("[RAPass::BuildDominators]\n");
#endif
if (_blocks.empty())
return kErrorOk;
RABlock* entryBlock = this->entryBlock();
entryBlock->setIDom(entryBlock);
bool changed = true;
uint32_t nIters = 0;
while (changed) {
nIters++;
changed = false;
uint32_t i = _pov.size();
while (i) {
RABlock* block = _pov[--i];
if (block == entryBlock)
continue;
RABlock* iDom = nullptr;
const RABlocks& preds = block->predecessors();
uint32_t j = preds.size();
while (j) {
RABlock* p = preds[--j];
if (!p->iDom()) continue;
iDom = !iDom ? p : intersectBlocks(iDom, p);
}
if (block->iDom() != iDom) {
ASMJIT_RA_LOG_FORMAT(" IDom of #%u -> #%u\n", block->blockId(), iDom->blockId());
block->setIDom(iDom);
changed = true;
}
}
}
ASMJIT_RA_LOG_FORMAT(" Done (%u iterations)\n", nIters);
return kErrorOk;
}
bool BaseRAPass::_strictlyDominates(const RABlock* a, const RABlock* b) const noexcept {
ASMJIT_ASSERT(a != nullptr); // There must be at least one block if this function is
ASMJIT_ASSERT(b != nullptr); // called, as both `a` and `b` must be valid blocks.
ASMJIT_ASSERT(a != b); // Checked by `dominates()` and `strictlyDominates()`.
// Nothing strictly dominates the entry block.
const RABlock* entryBlock = this->entryBlock();
if (a == entryBlock)
return false;
const RABlock* iDom = b->iDom();
while (iDom != a && iDom != entryBlock)
iDom = iDom->iDom();
return iDom != entryBlock;
}
const RABlock* BaseRAPass::_nearestCommonDominator(const RABlock* a, const RABlock* b) const noexcept {
ASMJIT_ASSERT(a != nullptr); // There must be at least one block if this function is
ASMJIT_ASSERT(b != nullptr); // called, as both `a` and `b` must be valid blocks.
ASMJIT_ASSERT(a != b); // Checked by `dominates()` and `properlyDominates()`.
if (a == b)
return a;
// If `a` strictly dominates `b` then `a` is the nearest common dominator.
if (_strictlyDominates(a, b))
return a;
// If `b` strictly dominates `a` then `b` is the nearest common dominator.
if (_strictlyDominates(b, a))
return b;
const RABlock* entryBlock = this->entryBlock();
uint64_t timestamp = nextTimestamp();
// Mark all A's dominators.
const RABlock* block = a->iDom();
while (block != entryBlock) {
block->setTimestamp(timestamp);
block = block->iDom();
}
// Check all B's dominators against marked dominators of A.
block = b->iDom();
while (block != entryBlock) {
if (block->hasTimestamp(timestamp))
return block;
block = block->iDom();
}
return entryBlock;
}
// ============================================================================
// [asmjit::BaseRAPass - CFG - Utilities]
// ============================================================================
Error BaseRAPass::removeUnreachableBlocks() noexcept {
uint32_t numAllBlocks = blockCount();
uint32_t numReachableBlocks = reachableBlockCount();
// All reachable -> nothing to do.
if (numAllBlocks == numReachableBlocks)
return kErrorOk;
#ifndef ASMJIT_NO_LOGGING
Logger* logger = debugLogger();
ASMJIT_RA_LOG_FORMAT("[RAPass::RemoveUnreachableBlocks (%u of %u unreachable)]\n", numAllBlocks - numReachableBlocks, numAllBlocks);
#endif
for (uint32_t i = 0; i < numAllBlocks; i++) {
RABlock* block = _blocks[i];
if (block->isReachable())
continue;
ASMJIT_RA_LOG_FORMAT(" Removing block {%u}\n", i);
BaseNode* first = block->first();
BaseNode* last = block->last();
BaseNode* beforeFirst = first->prev();
BaseNode* afterLast = last->next();
BaseNode* node = first;
while (node != afterLast) {
BaseNode* next = node->next();
if (node->isCode() || node->isRemovable())
cc()->removeNode(node);
node = next;
}
if (beforeFirst->next() == afterLast) {
block->setFirst(nullptr);
block->setLast(nullptr);
}
else {
block->setFirst(beforeFirst->next());
block->setLast(afterLast->prev());
}
}
return kErrorOk;
}
BaseNode* BaseRAPass::findSuccessorStartingAt(BaseNode* node) noexcept {
while (node && (node->isInformative() || node->hasNoEffect()))
node = node->next();
return node;
}
bool BaseRAPass::isNextTo(BaseNode* node, BaseNode* target) noexcept {
for (;;) {
node = node->next();
if (node == target)
return true;
if (!node)
return false;
if (node->isCode() || node->isData())
return false;
}
}
// ============================================================================
// [asmjit::BaseRAPass - ?]
// ============================================================================
Error BaseRAPass::_asWorkReg(VirtReg* vReg, RAWorkReg** out) noexcept {
// Checked by `asWorkReg()` - must be true.
ASMJIT_ASSERT(vReg->_workReg == nullptr);
uint32_t group = vReg->group();
ASMJIT_ASSERT(group < BaseReg::kGroupVirt);
RAWorkRegs& wRegs = workRegs();
RAWorkRegs& wRegsByGroup = workRegs(group);
ASMJIT_PROPAGATE(wRegs.willGrow(allocator()));
ASMJIT_PROPAGATE(wRegsByGroup.willGrow(allocator()));
RAWorkReg* wReg = zone()->newT<RAWorkReg>(vReg, wRegs.size());
if (ASMJIT_UNLIKELY(!wReg))
return DebugUtils::errored(kErrorOutOfMemory);
vReg->setWorkReg(wReg);
if (!vReg->isStack())
wReg->setRegByteMask(Support::lsbMask<uint64_t>(vReg->virtSize()));
wRegs.appendUnsafe(wReg);
wRegsByGroup.appendUnsafe(wReg);
// Only used by RA logging.
_maxWorkRegNameSize = Support::max(_maxWorkRegNameSize, vReg->nameSize());
*out = wReg;
return kErrorOk;
}
RAAssignment::WorkToPhysMap* BaseRAPass::newWorkToPhysMap() noexcept {
uint32_t count = workRegCount();
size_t size = WorkToPhysMap::sizeOf(count);
// If no registers are used it could be zero, in that case return a dummy
// map instead of NULL.
if (ASMJIT_UNLIKELY(!size)) {
static const RAAssignment::WorkToPhysMap nullMap = {{ 0 }};
return const_cast<RAAssignment::WorkToPhysMap*>(&nullMap);
}
WorkToPhysMap* map = zone()->allocT<WorkToPhysMap>(size);
if (ASMJIT_UNLIKELY(!map))
return nullptr;
map->reset(count);
return map;
}
RAAssignment::PhysToWorkMap* BaseRAPass::newPhysToWorkMap() noexcept {
uint32_t count = physRegTotal();
size_t size = PhysToWorkMap::sizeOf(count);
PhysToWorkMap* map = zone()->allocT<PhysToWorkMap>(size);
if (ASMJIT_UNLIKELY(!map))
return nullptr;
map->reset(count);
return map;
}
// ============================================================================
// [asmjit::BaseRAPass - Registers - Liveness Analysis and Statistics]
// ============================================================================
namespace LiveOps {
typedef ZoneBitVector::BitWord BitWord;
struct In {
static ASMJIT_INLINE BitWord op(BitWord dst, BitWord out, BitWord gen, BitWord kill) noexcept {
DebugUtils::unused(dst);
return (out | gen) & ~kill;
}
};
template<typename Operator>
static ASMJIT_INLINE bool op(BitWord* dst, const BitWord* a, uint32_t n) noexcept {
BitWord changed = 0;
for (uint32_t i = 0; i < n; i++) {
BitWord before = dst[i];
BitWord after = Operator::op(before, a[i]);
dst[i] = after;
changed |= (before ^ after);
}
return changed != 0;
}
template<typename Operator>
static ASMJIT_INLINE bool op(BitWord* dst, const BitWord* a, const BitWord* b, uint32_t n) noexcept {
BitWord changed = 0;
for (uint32_t i = 0; i < n; i++) {
BitWord before = dst[i];
BitWord after = Operator::op(before, a[i], b[i]);
dst[i] = after;
changed |= (before ^ after);
}
return changed != 0;
}
template<typename Operator>
static ASMJIT_INLINE bool op(BitWord* dst, const BitWord* a, const BitWord* b, const BitWord* c, uint32_t n) noexcept {
BitWord changed = 0;
for (uint32_t i = 0; i < n; i++) {
BitWord before = dst[i];
BitWord after = Operator::op(before, a[i], b[i], c[i]);
dst[i] = after;
changed |= (before ^ after);
}
return changed != 0;
}
static ASMJIT_INLINE bool recalcInOut(RABlock* block, uint32_t numBitWords, bool initial = false) noexcept {
bool changed = initial;
const RABlocks& successors = block->successors();
uint32_t numSuccessors = successors.size();
// Calculate `OUT` based on `IN` of all successors.
for (uint32_t i = 0; i < numSuccessors; i++)
changed |= op<Support::Or>(block->liveOut().data(), successors[i]->liveIn().data(), numBitWords);
// Calculate `IN` based on `OUT`, `GEN`, and `KILL` bits.
if (changed)
changed = op<In>(block->liveIn().data(), block->liveOut().data(), block->gen().data(), block->kill().data(), numBitWords);
return changed;
}
}
ASMJIT_FAVOR_SPEED Error BaseRAPass::buildLiveness() noexcept {
#ifndef ASMJIT_NO_LOGGING
Logger* logger = debugLogger();
StringTmp<512> sb;
#endif
ASMJIT_RA_LOG_FORMAT("[RAPass::BuildLiveness]\n");
uint32_t i;
uint32_t numAllBlocks = blockCount();
uint32_t numReachableBlocks = reachableBlockCount();
uint32_t numVisits = numReachableBlocks;
uint32_t numWorkRegs = workRegCount();
uint32_t numBitWords = ZoneBitVector::_wordsPerBits(numWorkRegs);
if (!numWorkRegs) {
ASMJIT_RA_LOG_FORMAT(" Done (no virtual registers)\n");
return kErrorOk;
}
ZoneVector<uint32_t> nUsesPerWorkReg; // Number of USEs of each RAWorkReg.
ZoneVector<uint32_t> nOutsPerWorkReg; // Number of OUTs of each RAWorkReg.
ZoneVector<uint32_t> nInstsPerBlock; // Number of instructions of each RABlock.
ASMJIT_PROPAGATE(nUsesPerWorkReg.resize(allocator(), numWorkRegs));
ASMJIT_PROPAGATE(nOutsPerWorkReg.resize(allocator(), numWorkRegs));
ASMJIT_PROPAGATE(nInstsPerBlock.resize(allocator(), numAllBlocks));
// --------------------------------------------------------------------------
// Calculate GEN/KILL of each block.
// --------------------------------------------------------------------------
for (i = 0; i < numReachableBlocks; i++) {
RABlock* block = _pov[i];
ASMJIT_PROPAGATE(block->resizeLiveBits(numWorkRegs));
BaseNode* node = block->last();
BaseNode* stop = block->first();
uint32_t nInsts = 0;
for (;;) {
if (node->isInst()) {
InstNode* inst = node->as<InstNode>();
RAInst* raInst = inst->passData<RAInst>();
ASMJIT_ASSERT(raInst != nullptr);
RATiedReg* tiedRegs = raInst->tiedRegs();
uint32_t count = raInst->tiedCount();
for (uint32_t j = 0; j < count; j++) {
RATiedReg* tiedReg = &tiedRegs[j];
uint32_t workId = tiedReg->workId();
// Update `nUses` and `nOuts`.
nUsesPerWorkReg[workId] += 1u;
nOutsPerWorkReg[workId] += uint32_t(tiedReg->isWrite());
// Mark as:
// KILL - if this VirtReg is killed afterwards.
// LAST - if this VirtReg is last in this basic block.
if (block->kill().bitAt(workId))
tiedReg->addFlags(RATiedReg::kKill);
else if (!block->gen().bitAt(workId))
tiedReg->addFlags(RATiedReg::kLast);
if (tiedReg->isWriteOnly()) {
// KILL.
block->kill().setBit(workId, true);
}
else {
// GEN.
block->kill().setBit(workId, false);
block->gen().setBit(workId, true);
}
}
nInsts++;
}
if (node == stop)
break;
node = node->prev();
ASMJIT_ASSERT(node != nullptr);
}
nInstsPerBlock[block->blockId()] = nInsts;
}
// --------------------------------------------------------------------------
// Calculate IN/OUT of each block.
// --------------------------------------------------------------------------
{
ZoneStack<RABlock*> workList;
ZoneBitVector workBits;
ASMJIT_PROPAGATE(workList.init(allocator()));
ASMJIT_PROPAGATE(workBits.resize(allocator(), blockCount(), true));
for (i = 0; i < numReachableBlocks; i++) {
RABlock* block = _pov[i];
LiveOps::recalcInOut(block, numBitWords, true);
ASMJIT_PROPAGATE(workList.append(block));
}
while (!workList.empty()) {
RABlock* block = workList.popFirst();
uint32_t blockId = block->blockId();
workBits.setBit(blockId, false);
if (LiveOps::recalcInOut(block, numBitWords)) {
const RABlocks& predecessors = block->predecessors();
uint32_t numPredecessors = predecessors.size();
for (uint32_t j = 0; j < numPredecessors; j++) {
RABlock* pred = predecessors[j];
if (!workBits.bitAt(pred->blockId())) {
workBits.setBit(pred->blockId(), true);
ASMJIT_PROPAGATE(workList.append(pred));
}
}
}
numVisits++;
}
workList.reset();
workBits.release(allocator());
}
ASMJIT_RA_LOG_COMPLEX({
logger->logf(" LiveIn/Out Done (%u visits)\n", numVisits);
for (i = 0; i < numAllBlocks; i++) {
RABlock* block = _blocks[i];
ASMJIT_PROPAGATE(sb.assignFormat(" {#%u}\n", block->blockId()));
ASMJIT_PROPAGATE(_dumpBlockLiveness(sb, block));
logger->log(sb);
}
});
// --------------------------------------------------------------------------
// Reserve the space in each `RAWorkReg` for references.
// --------------------------------------------------------------------------
for (i = 0; i < numWorkRegs; i++) {
RAWorkReg* workReg = workRegById(i);
ASMJIT_PROPAGATE(workReg->_refs.reserve(allocator(), nUsesPerWorkReg[i]));
ASMJIT_PROPAGATE(workReg->_writes.reserve(allocator(), nOutsPerWorkReg[i]));
}
// --------------------------------------------------------------------------
// Assign block and instruction positions, build LiveCount and LiveSpans.
// --------------------------------------------------------------------------
uint32_t position = 2;
for (i = 0; i < numAllBlocks; i++) {
RABlock* block = _blocks[i];
if (!block->isReachable())
continue;
BaseNode* node = block->first();
BaseNode* stop = block->last();
uint32_t endPosition = position + nInstsPerBlock[i] * 2;
block->setFirstPosition(position);
block->setEndPosition(endPosition);
RALiveCount curLiveCount;
RALiveCount maxLiveCount;
// Process LIVE-IN.
ZoneBitVector::ForEachBitSet it(block->liveIn());
while (it.hasNext()) {
RAWorkReg* workReg = _workRegs[uint32_t(it.next())];
curLiveCount[workReg->group()]++;
ASMJIT_PROPAGATE(workReg->liveSpans().openAt(allocator(), position, endPosition));
}
for (;;) {
if (node->isInst()) {
InstNode* inst = node->as<InstNode>();
RAInst* raInst = inst->passData<RAInst>();
ASMJIT_ASSERT(raInst != nullptr);
RATiedReg* tiedRegs = raInst->tiedRegs();
uint32_t count = raInst->tiedCount();
inst->setPosition(position);
raInst->_liveCount = curLiveCount;
for (uint32_t j = 0; j < count; j++) {
RATiedReg* tiedReg = &tiedRegs[j];
uint32_t workId = tiedReg->workId();
// Create refs and writes.
RAWorkReg* workReg = workRegById(workId);
workReg->_refs.appendUnsafe(node);
if (tiedReg->isWrite())
workReg->_writes.appendUnsafe(node);
// We couldn't calculate this in previous steps, but since we know all LIVE-OUT
// at this point it becomes trivial. If this is the last instruction that uses
// this `workReg` and it's not LIVE-OUT then it is KILLed here.
if (tiedReg->isLast() && !block->liveOut().bitAt(workId))
tiedReg->addFlags(RATiedReg::kKill);
LiveRegSpans& liveSpans = workReg->liveSpans();
bool wasOpen;
ASMJIT_PROPAGATE(liveSpans.openAt(allocator(), position + !tiedReg->isRead(), endPosition, wasOpen));
uint32_t group = workReg->group();
if (!wasOpen) {
curLiveCount[group]++;
raInst->_liveCount[group]++;
}
if (tiedReg->isKill()) {
liveSpans.closeAt(position + !tiedReg->isRead() + 1);
curLiveCount[group]--;
}
// Update `RAWorkReg::hintRegId`.
if (tiedReg->hasUseId() && !workReg->hasHintRegId()) {
uint32_t useId = tiedReg->useId();
if (!(raInst->_clobberedRegs[group] & Support::bitMask(useId)))
workReg->setHintRegId(useId);
}
// Update `RAWorkReg::clobberedSurvivalMask`.
if (raInst->_clobberedRegs[group] && !tiedReg->isOutOrKill())
workReg->addClobberSurvivalMask(raInst->_clobberedRegs[group]);
}
position += 2;
maxLiveCount.op<Support::Max>(raInst->_liveCount);
}
if (node == stop)
break;
node = node->next();
ASMJIT_ASSERT(node != nullptr);
}
block->_maxLiveCount = maxLiveCount;
_globalMaxLiveCount.op<Support::Max>(maxLiveCount);
ASMJIT_ASSERT(position == block->endPosition());
}
// --------------------------------------------------------------------------
// Calculate WorkReg statistics.
// --------------------------------------------------------------------------
for (i = 0; i < numWorkRegs; i++) {
RAWorkReg* workReg = _workRegs[i];
LiveRegSpans& spans = workReg->liveSpans();
uint32_t width = spans.width();
float freq = width ? float(double(workReg->_refs.size()) / double(width)) : float(0);
RALiveStats& stats = workReg->liveStats();
stats._width = width;
stats._freq = freq;
stats._priority = freq + float(int(workReg->virtReg()->weight())) * 0.01f;
}
ASMJIT_RA_LOG_COMPLEX({
sb.clear();
_dumpLiveSpans(sb);
logger->log(sb);
});
nUsesPerWorkReg.release(allocator());
nOutsPerWorkReg.release(allocator());
nInstsPerBlock.release(allocator());
return kErrorOk;
}
Error BaseRAPass::assignArgIndexToWorkRegs() noexcept {
ZoneBitVector& liveIn = entryBlock()->liveIn();
uint32_t argCount = func()->argCount();
for (uint32_t argIndex = 0; argIndex < argCount; argIndex++) {
for (uint32_t valueIndex = 0; valueIndex < Globals::kMaxValuePack; valueIndex++) {
// Unassigned argument.
VirtReg* virtReg = func()->argPack(argIndex)[valueIndex];
if (!virtReg)
continue;
// Unreferenced argument.
RAWorkReg* workReg = virtReg->workReg();
if (!workReg)
continue;
// Overwritten argument.
uint32_t workId = workReg->workId();
if (!liveIn.bitAt(workId))
continue;
workReg->setArgIndex(argIndex, valueIndex);
const FuncValue& arg = func()->detail().arg(argIndex, valueIndex);
if (arg.isReg() && _archTraits->regTypeToGroup(arg.regType()) == workReg->group()) {
workReg->setHintRegId(arg.regId());
}
}
}
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Allocation - Global]
// ============================================================================
#ifndef ASMJIT_NO_LOGGING
static void RAPass_dumpSpans(String& sb, uint32_t index, const LiveRegSpans& liveSpans) noexcept {
sb.appendFormat(" %02u: ", index);
for (uint32_t i = 0; i < liveSpans.size(); i++) {
const LiveRegSpan& liveSpan = liveSpans[i];
if (i) sb.append(", ");
sb.appendFormat("[%u:%u@%u]", liveSpan.a, liveSpan.b, liveSpan.id);
}
sb.append('\n');
}
#endif
Error BaseRAPass::runGlobalAllocator() noexcept {
ASMJIT_PROPAGATE(initGlobalLiveSpans());
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++) {
ASMJIT_PROPAGATE(binPack(group));
}
return kErrorOk;
}
ASMJIT_FAVOR_SPEED Error BaseRAPass::initGlobalLiveSpans() noexcept {
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++) {
size_t physCount = _physRegCount[group];
LiveRegSpans* liveSpans = nullptr;
if (physCount) {
liveSpans = allocator()->allocT<LiveRegSpans>(physCount * sizeof(LiveRegSpans));
if (ASMJIT_UNLIKELY(!liveSpans))
return DebugUtils::errored(kErrorOutOfMemory);
for (size_t physId = 0; physId < physCount; physId++)
new(&liveSpans[physId]) LiveRegSpans();
}
_globalLiveSpans[group] = liveSpans;
}
return kErrorOk;
}
ASMJIT_FAVOR_SPEED Error BaseRAPass::binPack(uint32_t group) noexcept {
if (workRegCount(group) == 0)
return kErrorOk;
#ifndef ASMJIT_NO_LOGGING
Logger* logger = debugLogger();
StringTmp<512> sb;
ASMJIT_RA_LOG_FORMAT("[RAPass::BinPack] Available=%u (0x%08X) Count=%u\n",
Support::popcnt(_availableRegs[group]),
_availableRegs[group],
workRegCount(group));
#endif
uint32_t i;
uint32_t physCount = _physRegCount[group];
RAWorkRegs workRegs;
LiveRegSpans tmpSpans;
ASMJIT_PROPAGATE(workRegs.concat(allocator(), this->workRegs(group)));
workRegs.sort([](const RAWorkReg* a, const RAWorkReg* b) noexcept {
return b->liveStats().priority() - a->liveStats().priority();
});
uint32_t numWorkRegs = workRegs.size();
uint32_t availableRegs = _availableRegs[group];
// First try to pack everything that provides register-id hint as these are
// most likely function arguments and fixed (precolored) virtual registers.
if (!workRegs.empty()) {
uint32_t dstIndex = 0;
for (i = 0; i < numWorkRegs; i++) {
RAWorkReg* workReg = workRegs[i];
if (workReg->hasHintRegId()) {
uint32_t physId = workReg->hintRegId();
if (availableRegs & Support::bitMask(physId)) {
LiveRegSpans& live = _globalLiveSpans[group][physId];
Error err = tmpSpans.nonOverlappingUnionOf(allocator(), live, workReg->liveSpans(), LiveRegData(workReg->virtId()));
if (err == kErrorOk) {
workReg->setHomeRegId(physId);
live.swap(tmpSpans);
continue;
}
if (ASMJIT_UNLIKELY(err != 0xFFFFFFFFu))
return err;
}
}
workRegs[dstIndex++] = workReg;
}
workRegs._setSize(dstIndex);
numWorkRegs = dstIndex;
}
// Try to pack the rest.
if (!workRegs.empty()) {
uint32_t dstIndex = 0;
for (i = 0; i < numWorkRegs; i++) {
RAWorkReg* workReg = workRegs[i];
uint32_t physRegs = availableRegs;
while (physRegs) {
uint32_t physId = Support::ctz(physRegs);
if (workReg->clobberSurvivalMask()) {
uint32_t preferredMask = physRegs & workReg->clobberSurvivalMask();
if (preferredMask)
physId = Support::ctz(preferredMask);
}
LiveRegSpans& live = _globalLiveSpans[group][physId];
Error err = tmpSpans.nonOverlappingUnionOf(allocator(), live, workReg->liveSpans(), LiveRegData(workReg->virtId()));
if (err == kErrorOk) {
workReg->setHomeRegId(physId);
live.swap(tmpSpans);
break;
}
if (ASMJIT_UNLIKELY(err != 0xFFFFFFFFu))
return err;
physRegs ^= Support::bitMask(physId);
}
// Keep it in `workRegs` if it was not allocated.
if (!physRegs)
workRegs[dstIndex++] = workReg;
}
workRegs._setSize(dstIndex);
numWorkRegs = dstIndex;
}
ASMJIT_RA_LOG_COMPLEX({
for (uint32_t physId = 0; physId < physCount; physId++) {
LiveRegSpans& live = _globalLiveSpans[group][physId];
if (live.empty())
continue;
sb.clear();
RAPass_dumpSpans(sb, physId, live);
logger->log(sb);
}
});
// Maybe unused if logging is disabled.
DebugUtils::unused(physCount);
if (workRegs.empty()) {
ASMJIT_RA_LOG_FORMAT(" Completed.\n");
}
else {
_strategy[group].setType(RAStrategy::kStrategyComplex);
for (RAWorkReg* workReg : workRegs)
workReg->markStackPreferred();
ASMJIT_RA_LOG_COMPLEX({
uint32_t count = workRegs.size();
sb.clear();
sb.appendFormat(" Unassigned (%u): ", count);
for (i = 0; i < numWorkRegs; i++) {
RAWorkReg* workReg = workRegs[i];
if (i) sb.append(", ");
sb.append(workReg->name());
}
sb.append('\n');
logger->log(sb);
});
}
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Allocation - Local]
// ============================================================================
Error BaseRAPass::runLocalAllocator() noexcept {
RALocalAllocator lra(this);
ASMJIT_PROPAGATE(lra.init());
if (!blockCount())
return kErrorOk;
// The allocation is done when this reaches zero.
uint32_t blocksRemaining = reachableBlockCount();
// Current block.
uint32_t blockId = 0;
RABlock* block = _blocks[blockId];
// The first block (entry) must always be reachable.
ASMJIT_ASSERT(block->isReachable());
// Assign function arguments for the initial block. The `lra` is valid now.
lra.makeInitialAssignment();
ASMJIT_PROPAGATE(setBlockEntryAssignment(block, block, lra._curAssignment));
// The loop starts from the first block and iterates blocks in order, however,
// the algorithm also allows to jump to any other block when finished if it's
// a jump target. In-order iteration just makes sure that all blocks are visited.
for (;;) {
BaseNode* first = block->first();
BaseNode* last = block->last();
BaseNode* terminator = block->hasTerminator() ? last : nullptr;
BaseNode* beforeFirst = first->prev();
BaseNode* afterLast = last->next();
bool unconditionalJump = false;
RABlock* consecutive = nullptr;
if (block->hasSuccessors())
consecutive = block->successors()[0];
lra.setBlock(block);
block->makeAllocated();
BaseNode* node = first;
while (node != afterLast) {
BaseNode* next = node->next();
if (node->isInst()) {
InstNode* inst = node->as<InstNode>();
if (ASMJIT_UNLIKELY(inst == terminator)) {
const RABlocks& successors = block->successors();
if (block->hasConsecutive()) {
ASMJIT_PROPAGATE(lra.allocBranch(inst, successors.last(), successors.first()));
node = next;
continue;
}
else if (successors.size() > 1) {
RABlock* cont = block->hasConsecutive() ? successors.first() : nullptr;
ASMJIT_PROPAGATE(lra.allocJumpTable(inst, successors, cont));
node = next;
continue;
}
else {
// Otherwise this is an unconditional jump, special handling isn't required.
unconditionalJump = true;
}
}
ASMJIT_PROPAGATE(lra.allocInst(inst));
if (inst->type() == BaseNode::kNodeInvoke)
ASMJIT_PROPAGATE(emitPreCall(inst->as<InvokeNode>()));
else
ASMJIT_PROPAGATE(lra.spillAfterAllocation(inst));
}
node = next;
}
if (consecutive) {
BaseNode* prev = afterLast ? afterLast->prev() : cc()->lastNode();
cc()->_setCursor(unconditionalJump ? prev->prev() : prev);
if (consecutive->hasEntryAssignment()) {
ASMJIT_PROPAGATE(
lra.switchToAssignment(
consecutive->entryPhysToWorkMap(),
consecutive->entryWorkToPhysMap(),
consecutive->liveIn(),
consecutive->isAllocated(),
false));
}
else {
ASMJIT_PROPAGATE(lra.spillRegsBeforeEntry(consecutive));
ASMJIT_PROPAGATE(setBlockEntryAssignment(consecutive, block, lra._curAssignment));
lra._curAssignment.copyFrom(consecutive->entryPhysToWorkMap(), consecutive->entryWorkToPhysMap());
}
}
// Important as the local allocator can insert instructions before
// and after any instruction within the basic block.
block->setFirst(beforeFirst->next());
block->setLast(afterLast ? afterLast->prev() : cc()->lastNode());
if (--blocksRemaining == 0)
break;
// Switch to the next consecutive block, if any.
if (consecutive) {
block = consecutive;
if (!block->isAllocated())
continue;
}
// Get the next block.
for (;;) {
if (++blockId >= blockCount())
blockId = 0;
block = _blocks[blockId];
if (!block->isReachable() || block->isAllocated() || !block->hasEntryAssignment())
continue;
break;
}
// If we switched to some block we have to update the local allocator.
lra.replaceAssignment(block->entryPhysToWorkMap(), block->entryWorkToPhysMap());
}
_clobberedRegs.op<Support::Or>(lra._clobberedRegs);
return kErrorOk;
}
Error BaseRAPass::setBlockEntryAssignment(RABlock* block, const RABlock* fromBlock, const RAAssignment& fromAssignment) noexcept {
if (block->hasSharedAssignmentId()) {
uint32_t sharedAssignmentId = block->sharedAssignmentId();
// Shouldn't happen. Entry assignment of a block that has a shared-state
// will assign to all blocks with the same sharedAssignmentId. It's a bug if
// the shared state has been already assigned.
if (!_sharedAssignments[sharedAssignmentId].empty())
return DebugUtils::errored(kErrorInvalidState);
return setSharedAssignment(sharedAssignmentId, fromAssignment);
}
PhysToWorkMap* physToWorkMap = clonePhysToWorkMap(fromAssignment.physToWorkMap());
WorkToPhysMap* workToPhysMap = cloneWorkToPhysMap(fromAssignment.workToPhysMap());
if (ASMJIT_UNLIKELY(!physToWorkMap || !workToPhysMap))
return DebugUtils::errored(kErrorOutOfMemory);
block->setEntryAssignment(physToWorkMap, workToPhysMap);
// True if this is the first (entry) block, nothing to do in this case.
if (block == fromBlock) {
// Entry block should never have a shared state.
if (block->hasSharedAssignmentId())
return DebugUtils::errored(kErrorInvalidState);
return kErrorOk;
}
RAAssignment as;
as.initLayout(_physRegCount, workRegs());
as.initMaps(physToWorkMap, workToPhysMap);
const ZoneBitVector& liveOut = fromBlock->liveOut();
const ZoneBitVector& liveIn = block->liveIn();
// It's possible that `fromBlock` has LIVE-OUT regs that `block` doesn't
// have in LIVE-IN, these have to be unassigned.
{
ZoneBitVector::ForEachBitOp<Support::AndNot> it(liveOut, liveIn);
while (it.hasNext()) {
uint32_t workId = uint32_t(it.next());
RAWorkReg* workReg = workRegById(workId);
uint32_t group = workReg->group();
uint32_t physId = as.workToPhysId(group, workId);
if (physId != RAAssignment::kPhysNone)
as.unassign(group, workId, physId);
}
}
return blockEntryAssigned(as);
}
Error BaseRAPass::setSharedAssignment(uint32_t sharedAssignmentId, const RAAssignment& fromAssignment) noexcept {
ASMJIT_ASSERT(_sharedAssignments[sharedAssignmentId].empty());
PhysToWorkMap* physToWorkMap = clonePhysToWorkMap(fromAssignment.physToWorkMap());
WorkToPhysMap* workToPhysMap = cloneWorkToPhysMap(fromAssignment.workToPhysMap());
if (ASMJIT_UNLIKELY(!physToWorkMap || !workToPhysMap))
return DebugUtils::errored(kErrorOutOfMemory);
_sharedAssignments[sharedAssignmentId].assignMaps(physToWorkMap, workToPhysMap);
ZoneBitVector& sharedLiveIn = _sharedAssignments[sharedAssignmentId]._liveIn;
ASMJIT_PROPAGATE(sharedLiveIn.resize(allocator(), workRegCount()));
RAAssignment as;
as.initLayout(_physRegCount, workRegs());
uint32_t sharedAssigned[BaseReg::kGroupVirt] {};
for (RABlock* block : blocks()) {
if (block->sharedAssignmentId() == sharedAssignmentId) {
ASMJIT_ASSERT(!block->hasEntryAssignment());
PhysToWorkMap* entryPhysToWorkMap = clonePhysToWorkMap(fromAssignment.physToWorkMap());
WorkToPhysMap* entryWorkToPhysMap = cloneWorkToPhysMap(fromAssignment.workToPhysMap());
if (ASMJIT_UNLIKELY(!entryPhysToWorkMap || !entryWorkToPhysMap))
return DebugUtils::errored(kErrorOutOfMemory);
block->setEntryAssignment(entryPhysToWorkMap, entryWorkToPhysMap);
as.initMaps(entryPhysToWorkMap, entryWorkToPhysMap);
const ZoneBitVector& liveIn = block->liveIn();
sharedLiveIn.or_(liveIn);
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++) {
sharedAssigned[group] |= entryPhysToWorkMap->assigned[group];
Support::BitWordIterator<uint32_t> it(entryPhysToWorkMap->assigned[group]);
while (it.hasNext()) {
uint32_t physId = it.next();
uint32_t workId = as.physToWorkId(group, physId);
if (!liveIn.bitAt(workId))
as.unassign(group, workId, physId);
}
}
}
}
{
as.initMaps(physToWorkMap, workToPhysMap);
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++) {
Support::BitWordIterator<uint32_t> it(_availableRegs[group] & ~sharedAssigned[group]);
while (it.hasNext()) {
uint32_t physId = it.next();
if (as.isPhysAssigned(group, physId)) {
uint32_t workId = as.physToWorkId(group, physId);
as.unassign(group, workId, physId);
}
}
}
}
return blockEntryAssigned(as);
}
Error BaseRAPass::blockEntryAssigned(const RAAssignment& as) noexcept {
// Complex allocation strategy requires to record register assignments upon
// block entry (or per shared state).
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++) {
if (!_strategy[group].isComplex())
continue;
Support::BitWordIterator<uint32_t> it(as.assigned(group));
while (it.hasNext()) {
uint32_t physId = it.next();
uint32_t workId = as.physToWorkId(group, physId);
RAWorkReg* workReg = workRegById(workId);
workReg->addAllocatedMask(Support::bitMask(physId));
}
}
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Allocation - Utilities]
// ============================================================================
Error BaseRAPass::useTemporaryMem(BaseMem& out, uint32_t size, uint32_t alignment) noexcept {
ASMJIT_ASSERT(alignment <= 64);
if (_temporaryMem.isNone()) {
ASMJIT_PROPAGATE(cc()->_newStack(&_temporaryMem.as<BaseMem>(), size, alignment));
}
else {
ASMJIT_ASSERT(_temporaryMem.as<BaseMem>().isRegHome());
uint32_t virtId = _temporaryMem.as<BaseMem>().baseId();
VirtReg* virtReg = cc()->virtRegById(virtId);
cc()->setStackSize(virtId, Support::max(virtReg->virtSize(), size),
Support::max(virtReg->alignment(), alignment));
}
out = _temporaryMem.as<BaseMem>();
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Allocation - Prolog / Epilog]
// ============================================================================
Error BaseRAPass::updateStackFrame() noexcept {
// Update some StackFrame information that we updated during allocation. The
// only information we don't have at the moment is final local stack size,
// which is calculated last.
FuncFrame& frame = func()->frame();
for (uint32_t group = 0; group < BaseReg::kGroupVirt; group++)
frame.addDirtyRegs(group, _clobberedRegs[group]);
frame.setLocalStackAlignment(_stackAllocator.alignment());
// If there are stack arguments that are not assigned to registers upon entry
// and the function doesn't require dynamic stack alignment we keep these
// arguments where they are. This will also mark all stack slots that match
// these arguments as allocated.
if (_numStackArgsToStackSlots)
ASMJIT_PROPAGATE(_markStackArgsToKeep());
// Calculate offsets of all stack slots and update StackSize to reflect the calculated local stack size.
ASMJIT_PROPAGATE(_stackAllocator.calculateStackFrame());
frame.setLocalStackSize(_stackAllocator.stackSize());
// Update the stack frame based on `_argsAssignment` and finalize it.
// Finalization means to apply final calculation to the stack layout.
ASMJIT_PROPAGATE(_argsAssignment.updateFuncFrame(frame));
ASMJIT_PROPAGATE(frame.finalize());
// StackAllocator allocates all stots starting from [0], adjust them when necessary.
if (frame.localStackOffset() != 0)
ASMJIT_PROPAGATE(_stackAllocator.adjustSlotOffsets(int32_t(frame.localStackOffset())));
// Again, if there are stack arguments allocated in function's stack we have
// to handle them. This handles all cases (either regular or dynamic stack
// alignment).
if (_numStackArgsToStackSlots)
ASMJIT_PROPAGATE(_updateStackArgs());
return kErrorOk;
}
Error BaseRAPass::_markStackArgsToKeep() noexcept {
FuncFrame& frame = func()->frame();
bool hasSAReg = frame.hasPreservedFP() || !frame.hasDynamicAlignment();
RAWorkRegs& workRegs = _workRegs;
uint32_t numWorkRegs = workRegCount();
for (uint32_t workId = 0; workId < numWorkRegs; workId++) {
RAWorkReg* workReg = workRegs[workId];
if (workReg->hasFlag(RAWorkReg::kFlagStackArgToStack)) {
ASMJIT_ASSERT(workReg->hasArgIndex());
const FuncValue& srcArg = _func->detail().arg(workReg->argIndex());
// If the register doesn't have stack slot then we failed. It doesn't
// make much sense as it was marked as `kFlagStackArgToStack`, which
// requires the WorkReg was live-in upon function entry.
RAStackSlot* slot = workReg->stackSlot();
if (ASMJIT_UNLIKELY(!slot))
return DebugUtils::errored(kErrorInvalidState);
if (hasSAReg && srcArg.isStack() && !srcArg.isIndirect()) {
uint32_t typeSize = Type::sizeOf(srcArg.typeId());
if (typeSize == slot->size()) {
slot->addFlags(RAStackSlot::kFlagStackArg);
continue;
}
}
// NOTE: Update StackOffset here so when `_argsAssignment.updateFuncFrame()`
// is called it will take into consideration moving to stack slots. Without
// this we may miss some scratch registers later.
FuncValue& dstArg = _argsAssignment.arg(workReg->argIndex(), workReg->argValueIndex());
dstArg.assignStackOffset(0);
}
}
return kErrorOk;
}
Error BaseRAPass::_updateStackArgs() noexcept {
FuncFrame& frame = func()->frame();
RAWorkRegs& workRegs = _workRegs;
uint32_t numWorkRegs = workRegCount();
for (uint32_t workId = 0; workId < numWorkRegs; workId++) {
RAWorkReg* workReg = workRegs[workId];
if (workReg->hasFlag(RAWorkReg::kFlagStackArgToStack)) {
ASMJIT_ASSERT(workReg->hasArgIndex());
RAStackSlot* slot = workReg->stackSlot();
if (ASMJIT_UNLIKELY(!slot))
return DebugUtils::errored(kErrorInvalidState);
if (slot->isStackArg()) {
const FuncValue& srcArg = _func->detail().arg(workReg->argIndex());
if (frame.hasPreservedFP()) {
slot->setBaseRegId(_fp.id());
slot->setOffset(int32_t(frame.saOffsetFromSA()) + srcArg.stackOffset());
}
else {
slot->setOffset(int32_t(frame.saOffsetFromSP()) + srcArg.stackOffset());
}
}
else {
FuncValue& dstArg = _argsAssignment.arg(workReg->argIndex(), workReg->argValueIndex());
dstArg.setStackOffset(slot->offset());
}
}
}
return kErrorOk;
}
Error BaseRAPass::insertPrologEpilog() noexcept {
FuncFrame& frame = _func->frame();
cc()->_setCursor(func());
ASMJIT_PROPAGATE(cc()->emitProlog(frame));
ASMJIT_PROPAGATE(_iEmitHelper->emitArgsAssignment(frame, _argsAssignment));
cc()->_setCursor(func()->exitNode());
ASMJIT_PROPAGATE(cc()->emitEpilog(frame));
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Rewriter]
// ============================================================================
Error BaseRAPass::rewrite() noexcept {
#ifndef ASMJIT_NO_LOGGING
Logger* logger = debugLogger();
ASMJIT_RA_LOG_FORMAT("[RAPass::Rewrite]\n");
#endif
return _rewrite(_func, _stop);
}
ASMJIT_FAVOR_SPEED Error BaseRAPass::_rewrite(BaseNode* first, BaseNode* stop) noexcept {
uint32_t virtCount = cc()->_vRegArray.size();
BaseNode* node = first;
while (node != stop) {
BaseNode* next = node->next();
if (node->isInst()) {
InstNode* inst = node->as<InstNode>();
RAInst* raInst = node->passData<RAInst>();
Operand* operands = inst->operands();
uint32_t opCount = inst->opCount();
uint32_t i;
// Rewrite virtual registers into physical registers.
if (ASMJIT_LIKELY(raInst)) {
// If the instruction contains pass data (raInst) then it was a subject
// for register allocation and must be rewritten to use physical regs.
RATiedReg* tiedRegs = raInst->tiedRegs();
uint32_t tiedCount = raInst->tiedCount();
for (i = 0; i < tiedCount; i++) {
RATiedReg* tiedReg = &tiedRegs[i];
Support::BitWordIterator<uint32_t> useIt(tiedReg->useRewriteMask());
uint32_t useId = tiedReg->useId();
while (useIt.hasNext()) inst->rewriteIdAtIndex(useIt.next(), useId);
Support::BitWordIterator<uint32_t> outIt(tiedReg->outRewriteMask());
uint32_t outId = tiedReg->outId();
while (outIt.hasNext()) inst->rewriteIdAtIndex(outIt.next(), outId);
}
// This data is allocated by Zone passed to `runOnFunction()`, which
// will be reset after the RA pass finishes. So reset this data to
// prevent having a dead pointer after RA pass is complete.
node->resetPassData();
if (ASMJIT_UNLIKELY(node->type() != BaseNode::kNodeInst)) {
// FuncRet terminates the flow, it must either be removed if the exit
// label is next to it (optimization) or patched to an architecture
// dependent jump instruction that jumps to the function's exit before
// the epilog.
if (node->type() == BaseNode::kNodeFuncRet) {
RABlock* block = raInst->block();
if (!isNextTo(node, _func->exitNode())) {
cc()->_setCursor(node->prev());
ASMJIT_PROPAGATE(emitJump(_func->exitNode()->label()));
}
BaseNode* prev = node->prev();
cc()->removeNode(node);
block->setLast(prev);
}
}
}
// Rewrite stack slot addresses.
for (i = 0; i < opCount; i++) {
Operand& op = operands[i];
if (op.isMem()) {
BaseMem& mem = op.as<BaseMem>();
if (mem.isRegHome()) {
uint32_t virtIndex = Operand::virtIdToIndex(mem.baseId());
if (ASMJIT_UNLIKELY(virtIndex >= virtCount))
return DebugUtils::errored(kErrorInvalidVirtId);
VirtReg* virtReg = cc()->virtRegByIndex(virtIndex);
RAWorkReg* workReg = virtReg->workReg();
ASMJIT_ASSERT(workReg != nullptr);
RAStackSlot* slot = workReg->stackSlot();
int32_t offset = slot->offset();
mem._setBase(_sp.type(), slot->baseRegId());
mem.clearRegHome();
mem.addOffsetLo32(offset);
}
}
}
}
node = next;
}
return kErrorOk;
}
// ============================================================================
// [asmjit::BaseRAPass - Logging]
// ============================================================================
#ifndef ASMJIT_NO_LOGGING
static void RAPass_dumpRAInst(BaseRAPass* pass, String& sb, const RAInst* raInst) noexcept {
const RATiedReg* tiedRegs = raInst->tiedRegs();
uint32_t tiedCount = raInst->tiedCount();
for (uint32_t i = 0; i < tiedCount; i++) {
const RATiedReg& tiedReg = tiedRegs[i];
if (i != 0)
sb.append(' ');
sb.appendFormat("%s{", pass->workRegById(tiedReg.workId())->name());
sb.append(tiedReg.isReadWrite() ? 'X' :
tiedReg.isRead() ? 'R' :
tiedReg.isWrite() ? 'W' : '?');
if (tiedReg.hasUseId())
sb.appendFormat("|Use=%u", tiedReg.useId());
else if (tiedReg.isUse())
sb.append("|Use");
if (tiedReg.hasOutId())
sb.appendFormat("|Out=%u", tiedReg.outId());
else if (tiedReg.isOut())
sb.append("|Out");
if (tiedReg.isLast())
sb.append("|Last");
if (tiedReg.isKill())
sb.append("|Kill");
sb.append("}");
}
}
ASMJIT_FAVOR_SIZE Error BaseRAPass::annotateCode() noexcept {
uint32_t loggerFlags = _loggerFlags;
StringTmp<1024> sb;
for (const RABlock* block : _blocks) {
BaseNode* node = block->first();
if (!node) continue;
BaseNode* last = block->last();
for (;;) {
sb.clear();
Formatter::formatNode(sb, loggerFlags, cc(), node);
if ((loggerFlags & FormatOptions::kFlagDebugRA) != 0 && node->isInst() && node->hasPassData()) {
const RAInst* raInst = node->passData<RAInst>();
if (raInst->tiedCount() > 0) {
sb.padEnd(40);
sb.append(" | ");
RAPass_dumpRAInst(this, sb, raInst);
}
}
node->setInlineComment(
static_cast<char*>(
cc()->_dataZone.dup(sb.data(), sb.size(), true)));
if (node == last)
break;
node = node->next();
}
}
return kErrorOk;
}
ASMJIT_FAVOR_SIZE Error BaseRAPass::_dumpBlockIds(String& sb, const RABlocks& blocks) noexcept {
for (uint32_t i = 0, size = blocks.size(); i < size; i++) {
const RABlock* block = blocks[i];
if (i != 0)
ASMJIT_PROPAGATE(sb.appendFormat(", #%u", block->blockId()));
else
ASMJIT_PROPAGATE(sb.appendFormat("#%u", block->blockId()));
}
return kErrorOk;
}
ASMJIT_FAVOR_SIZE Error BaseRAPass::_dumpBlockLiveness(String& sb, const RABlock* block) noexcept {
for (uint32_t liveType = 0; liveType < RABlock::kLiveCount; liveType++) {
const char* bitsName = liveType == RABlock::kLiveIn ? "IN " :
liveType == RABlock::kLiveOut ? "OUT " :
liveType == RABlock::kLiveGen ? "GEN " : "KILL";
const ZoneBitVector& bits = block->_liveBits[liveType];
uint32_t size = bits.size();
ASMJIT_ASSERT(size <= workRegCount());
uint32_t n = 0;
for (uint32_t workId = 0; workId < size; workId++) {
if (bits.bitAt(workId)) {
RAWorkReg* wReg = workRegById(workId);
if (!n)
sb.appendFormat(" %s [", bitsName);
else
sb.append(", ");
sb.append(wReg->name());
n++;
}
}
if (n)
sb.append("]\n");
}
return kErrorOk;
}
ASMJIT_FAVOR_SIZE Error BaseRAPass::_dumpLiveSpans(String& sb) noexcept {
uint32_t numWorkRegs = _workRegs.size();
uint32_t maxSize = _maxWorkRegNameSize;
for (uint32_t workId = 0; workId < numWorkRegs; workId++) {
RAWorkReg* workReg = _workRegs[workId];
sb.append(" ");
size_t oldSize = sb.size();
sb.append(workReg->name());
sb.padEnd(oldSize + maxSize);
RALiveStats& stats = workReg->liveStats();
sb.appendFormat(" {id:%04u width: %-4u freq: %0.4f priority=%0.4f}",
workReg->virtId(),
stats.width(),
stats.freq(),
stats.priority());
sb.append(": ");
LiveRegSpans& liveSpans = workReg->liveSpans();
for (uint32_t x = 0; x < liveSpans.size(); x++) {
const LiveRegSpan& liveSpan = liveSpans[x];
if (x)
sb.append(", ");
sb.appendFormat("[%u:%u]", liveSpan.a, liveSpan.b);
}
sb.append('\n');
}
return kErrorOk;
}
#endif
ASMJIT_END_NAMESPACE
#endif // !ASMJIT_NO_COMPILER