// Copyright 2019 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <string>
#include "common/assert.h"
#include "common/common_types.h"
#include "video_core/shader/ast.h"
#include "video_core/shader/expr.h"
namespace VideoCommon::Shader {
ASTZipper::ASTZipper() = default;
void ASTZipper::Init(ASTNode new_first, ASTNode parent) {
ASSERT(new_first->manager == nullptr);
first = new_first;
last = new_first;
ASTNode current = first;
while (current) {
current->manager = this;
current->parent = parent;
last = current;
current = current->next;
}
}
void ASTZipper::PushBack(ASTNode new_node) {
ASSERT(new_node->manager == nullptr);
new_node->previous = last;
if (last) {
last->next = new_node;
}
new_node->next.reset();
last = new_node;
if (!first) {
first = new_node;
}
new_node->manager = this;
}
void ASTZipper::PushFront(ASTNode new_node) {
ASSERT(new_node->manager == nullptr);
new_node->previous.reset();
new_node->next = first;
if (first) {
first->previous = new_node;
}
if (last == first) {
last = new_node;
}
first = new_node;
new_node->manager = this;
}
void ASTZipper::InsertAfter(ASTNode new_node, ASTNode at_node) {
ASSERT(new_node->manager == nullptr);
if (!at_node) {
PushFront(new_node);
return;
}
ASTNode next = at_node->next;
if (next) {
next->previous = new_node;
}
new_node->previous = at_node;
if (at_node == last) {
last = new_node;
}
new_node->next = next;
at_node->next = new_node;
new_node->manager = this;
}
void ASTZipper::InsertBefore(ASTNode new_node, ASTNode at_node) {
ASSERT(new_node->manager == nullptr);
if (!at_node) {
PushBack(new_node);
return;
}
ASTNode previous = at_node->previous;
if (previous) {
previous->next = new_node;
}
new_node->next = at_node;
if (at_node == first) {
first = new_node;
}
new_node->previous = previous;
at_node->previous = new_node;
new_node->manager = this;
}
void ASTZipper::DetachTail(ASTNode node) {
ASSERT(node->manager == this);
if (node == first) {
first.reset();
last.reset();
return;
}
last = node->previous;
last->next.reset();
node->previous.reset();
ASTNode current = node;
while (current) {
current->manager = nullptr;
current->parent.reset();
current = current->next;
}
}
void ASTZipper::DetachSegment(ASTNode start, ASTNode end) {
ASSERT(start->manager == this && end->manager == this);
if (start == end) {
DetachSingle(start);
return;
}
ASTNode prev = start->previous;
ASTNode post = end->next;
if (!prev) {
first = post;
} else {
prev->next = post;
}
if (!post) {
last = prev;
} else {
post->previous = prev;
}
start->previous.reset();
end->next.reset();
ASTNode current = start;
bool found = false;
while (current) {
current->manager = nullptr;
current->parent.reset();
found |= current == end;
current = current->next;
}
ASSERT(found);
}
void ASTZipper::DetachSingle(ASTNode node) {
ASSERT(node->manager == this);
ASTNode prev = node->previous;
ASTNode post = node->next;
node->previous.reset();
node->next.reset();
if (!prev) {
first = post;
} else {
prev->next = post;
}
if (!post) {
last = prev;
} else {
post->previous = prev;
}
node->manager = nullptr;
node->parent.reset();
}
void ASTZipper::Remove(ASTNode node) {
ASSERT(node->manager == this);
ASTNode next = node->next;
ASTNode previous = node->previous;
if (previous) {
previous->next = next;
}
if (next) {
next->previous = previous;
}
node->parent.reset();
node->manager = nullptr;
if (node == last) {
last = previous;
}
if (node == first) {
first = next;
}
}
class ExprPrinter final {
public:
ExprPrinter() = default;
void operator()(ExprAnd const& expr) {
inner += "( ";
std::visit(*this, *expr.operand1);
inner += " && ";
std::visit(*this, *expr.operand2);
inner += ')';
}
void operator()(ExprOr const& expr) {
inner += "( ";
std::visit(*this, *expr.operand1);
inner += " || ";
std::visit(*this, *expr.operand2);
inner += ')';
}
void operator()(ExprNot const& expr) {
inner += "!";
std::visit(*this, *expr.operand1);
}
void operator()(ExprPredicate const& expr) {
inner += "P" + std::to_string(expr.predicate);
}
void operator()(ExprCondCode const& expr) {
u32 cc = static_cast<u32>(expr.cc);
inner += "CC" + std::to_string(cc);
}
void operator()(ExprVar const& expr) {
inner += "V" + std::to_string(expr.var_index);
}
void operator()(ExprBoolean const& expr) {
inner += expr.value ? "true" : "false";
}
std::string& GetResult() {
return inner;
}
std::string inner{};
};
class ASTPrinter {
public:
ASTPrinter() = default;
void operator()(ASTProgram& ast) {
scope++;
inner += "program {\n";
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
inner += "}\n";
scope--;
}
void operator()(ASTIfThen& ast) {
ExprPrinter expr_parser{};
std::visit(expr_parser, *ast.condition);
inner += Ident() + "if (" + expr_parser.GetResult() + ") {\n";
scope++;
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
scope--;
inner += Ident() + "}\n";
}
void operator()(ASTIfElse& ast) {
inner += Ident() + "else {\n";
scope++;
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
scope--;
inner += Ident() + "}\n";
}
void operator()(ASTBlockEncoded& ast) {
inner += Ident() + "Block(" + std::to_string(ast.start) + ", " + std::to_string(ast.end) +
");\n";
}
void operator()(ASTBlockDecoded& ast) {
inner += Ident() + "Block;\n";
}
void operator()(ASTVarSet& ast) {
ExprPrinter expr_parser{};
std::visit(expr_parser, *ast.condition);
inner +=
Ident() + "V" + std::to_string(ast.index) + " := " + expr_parser.GetResult() + ";\n";
}
void operator()(ASTLabel& ast) {
inner += "Label_" + std::to_string(ast.index) + ":\n";
}
void operator()(ASTGoto& ast) {
ExprPrinter expr_parser{};
std::visit(expr_parser, *ast.condition);
inner += Ident() + "(" + expr_parser.GetResult() + ") -> goto Label_" +
std::to_string(ast.label) + ";\n";
}
void operator()(ASTDoWhile& ast) {
ExprPrinter expr_parser{};
std::visit(expr_parser, *ast.condition);
inner += Ident() + "do {\n";
scope++;
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
scope--;
inner += Ident() + "} while (" + expr_parser.GetResult() + ");\n";
}
void operator()(ASTReturn& ast) {
ExprPrinter expr_parser{};
std::visit(expr_parser, *ast.condition);
inner += Ident() + "(" + expr_parser.GetResult() + ") -> " +
(ast.kills ? "discard" : "exit") + ";\n";
}
void operator()(ASTBreak& ast) {
ExprPrinter expr_parser{};
std::visit(expr_parser, *ast.condition);
inner += Ident() + "(" + expr_parser.GetResult() + ") -> break;\n";
}
std::string& Ident() {
if (memo_scope == scope) {
return tabs_memo;
}
tabs_memo = tabs.substr(0, scope * 2);
memo_scope = scope;
return tabs_memo;
}
void Visit(ASTNode& node) {
std::visit(*this, *node->GetInnerData());
}
std::string& GetResult() {
return inner;
}
private:
std::string inner{};
u32 scope{};
std::string tabs_memo{};
u32 memo_scope{};
static std::string tabs;
};
std::string ASTPrinter::tabs = " ";
std::string ASTManager::Print() {
ASTPrinter printer{};
printer.Visit(main_node);
return printer.GetResult();
}
void ASTManager::Decompile() {
auto it = gotos.begin();
while (it != gotos.end()) {
ASTNode goto_node = *it;
u32 label_index = goto_node->GetGotoLabel();
ASTNode label = labels[label_index];
if (IndirectlyRelated(goto_node, label)) {
while (!DirectlyRelated(goto_node, label)) {
MoveOutward(goto_node);
}
}
if (DirectlyRelated(goto_node, label)) {
u32 goto_level = goto_node->GetLevel();
u32 label_level = label->GetLevel();
while (label_level < goto_level) {
MoveOutward(goto_node);
goto_level--;
}
// TODO(Blinkhawk): Implement Lifting and Inward Movements
}
if (label->GetParent() == goto_node->GetParent()) {
bool is_loop = false;
ASTNode current = goto_node->GetPrevious();
while (current) {
if (current == label) {
is_loop = true;
break;
}
current = current->GetPrevious();
}
if (is_loop) {
EncloseDoWhile(goto_node, label);
} else {
EncloseIfThen(goto_node, label);
}
it = gotos.erase(it);
continue;
}
it++;
}
for (ASTNode label : labels) {
auto& manager = label->GetManager();
manager.Remove(label);
}
labels.clear();
}
bool ASTManager::IndirectlyRelated(ASTNode first, ASTNode second) {
return !(first->GetParent() == second->GetParent() || DirectlyRelated(first, second));
}
bool ASTManager::DirectlyRelated(ASTNode first, ASTNode second) {
if (first->GetParent() == second->GetParent()) {
return false;
}
u32 first_level = first->GetLevel();
u32 second_level = second->GetLevel();
u32 min_level;
u32 max_level;
ASTNode max;
ASTNode min;
if (first_level > second_level) {
min_level = second_level;
min = second;
max_level = first_level;
max = first;
} else {
min_level = first_level;
min = first;
max_level = second_level;
max = second;
}
while (max_level > min_level) {
max_level--;
max = max->GetParent();
}
return (min->GetParent() == max->GetParent());
}
void ASTManager::ShowCurrentState(std::string state) {
LOG_CRITICAL(HW_GPU, "\nState {}:\n\n{}\n", state, Print());
SanityCheck();
}
void ASTManager::SanityCheck() {
for (auto label : labels) {
if (!label->GetParent()) {
LOG_CRITICAL(HW_GPU, "Sanity Check Failed");
}
}
}
void ASTManager::EncloseDoWhile(ASTNode goto_node, ASTNode label) {
// ShowCurrentState("Before DoWhile Enclose");
enclose_count++;
ASTZipper& zipper = goto_node->GetManager();
ASTNode loop_start = label->GetNext();
if (loop_start == goto_node) {
zipper.Remove(goto_node);
// ShowCurrentState("Ignore DoWhile Enclose");
return;
}
ASTNode parent = label->GetParent();
Expr condition = goto_node->GetGotoCondition();
zipper.DetachSegment(loop_start, goto_node);
ASTNode do_while_node = ASTBase::Make<ASTDoWhile>(parent, condition);
ASTZipper* sub_zipper = do_while_node->GetSubNodes();
sub_zipper->Init(loop_start, do_while_node);
zipper.InsertAfter(do_while_node, label);
sub_zipper->Remove(goto_node);
// ShowCurrentState("After DoWhile Enclose");
}
void ASTManager::EncloseIfThen(ASTNode goto_node, ASTNode label) {
// ShowCurrentState("Before IfThen Enclose");
enclose_count++;
ASTZipper& zipper = goto_node->GetManager();
ASTNode if_end = label->GetPrevious();
if (if_end == goto_node) {
zipper.Remove(goto_node);
// ShowCurrentState("Ignore IfThen Enclose");
return;
}
ASTNode prev = goto_node->GetPrevious();
Expr condition = goto_node->GetGotoCondition();
bool do_else = false;
if (prev->IsIfThen()) {
Expr if_condition = prev->GetIfCondition();
do_else = ExprAreEqual(if_condition, condition);
}
ASTNode parent = label->GetParent();
zipper.DetachSegment(goto_node, if_end);
ASTNode if_node;
if (do_else) {
if_node = ASTBase::Make<ASTIfElse>(parent);
} else {
Expr neg_condition = MakeExprNot(condition);
if_node = ASTBase::Make<ASTIfThen>(parent, neg_condition);
}
ASTZipper* sub_zipper = if_node->GetSubNodes();
sub_zipper->Init(goto_node, if_node);
zipper.InsertAfter(if_node, prev);
sub_zipper->Remove(goto_node);
// ShowCurrentState("After IfThen Enclose");
}
void ASTManager::MoveOutward(ASTNode goto_node) {
// ShowCurrentState("Before MoveOutward");
outward_count++;
ASTZipper& zipper = goto_node->GetManager();
ASTNode parent = goto_node->GetParent();
ASTZipper& zipper2 = parent->GetManager();
ASTNode grandpa = parent->GetParent();
bool is_loop = parent->IsLoop();
bool is_else = parent->IsIfElse();
bool is_if = parent->IsIfThen();
ASTNode prev = goto_node->GetPrevious();
ASTNode post = goto_node->GetNext();
Expr condition = goto_node->GetGotoCondition();
zipper.DetachSingle(goto_node);
if (is_loop) {
u32 var_index = NewVariable();
Expr var_condition = MakeExpr<ExprVar>(var_index);
ASTNode var_node = ASTBase::Make<ASTVarSet>(parent, var_index, condition);
ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, true_condition);
zipper2.InsertBefore(var_node_init, parent);
zipper.InsertAfter(var_node, prev);
goto_node->SetGotoCondition(var_condition);
ASTNode break_node = ASTBase::Make<ASTBreak>(parent, var_condition);
zipper.InsertAfter(break_node, var_node);
} else if (is_if || is_else) {
if (post) {
u32 var_index = NewVariable();
Expr var_condition = MakeExpr<ExprVar>(var_index);
ASTNode var_node = ASTBase::Make<ASTVarSet>(parent, var_index, condition);
ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, true_condition);
if (is_if) {
zipper2.InsertBefore(var_node_init, parent);
} else {
zipper2.InsertBefore(var_node_init, parent->GetPrevious());
}
zipper.InsertAfter(var_node, prev);
goto_node->SetGotoCondition(var_condition);
zipper.DetachTail(post);
ASTNode if_node = ASTBase::Make<ASTIfThen>(parent, MakeExprNot(var_condition));
ASTZipper* sub_zipper = if_node->GetSubNodes();
sub_zipper->Init(post, if_node);
zipper.InsertAfter(if_node, var_node);
} else {
Expr if_condition;
if (is_if) {
if_condition = parent->GetIfCondition();
} else {
ASTNode if_node = parent->GetPrevious();
if_condition = MakeExprNot(if_node->GetIfCondition());
}
Expr new_condition = MakeExprAnd(if_condition, condition);
goto_node->SetGotoCondition(new_condition);
}
} else {
UNREACHABLE();
}
ASTNode next = parent->GetNext();
if (is_if && next && next->IsIfElse()) {
zipper2.InsertAfter(goto_node, next);
goto_node->SetParent(grandpa);
// ShowCurrentState("After MoveOutward");
return;
}
zipper2.InsertAfter(goto_node, parent);
goto_node->SetParent(grandpa);
// ShowCurrentState("After MoveOutward");
}
} // namespace VideoCommon::Shader