suyu/src/video_core/shader/track.cpp
Lioncash bebbdc2067 shader_ir: std::move Node instance where applicable
These are std::shared_ptr instances underneath the hood, which means
copying them isn't as cheap as a regular pointer. Particularly so on
weakly-ordered systems.

This avoids atomic reference count increments and decrements where they
aren't necessary for the core set of operations.
2019-07-16 19:49:23 -04:00

111 lines
4 KiB
C++

// Copyright 2018 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <utility>
#include <variant>
#include "common/common_types.h"
#include "video_core/shader/shader_ir.h"
namespace VideoCommon::Shader {
namespace {
std::pair<Node, s64> FindOperation(const NodeBlock& code, s64 cursor,
OperationCode operation_code) {
for (; cursor >= 0; --cursor) {
Node node = code.at(cursor);
if (const auto operation = std::get_if<OperationNode>(&*node)) {
if (operation->GetCode() == operation_code) {
return {std::move(node), cursor};
}
}
if (const auto conditional = std::get_if<ConditionalNode>(&*node)) {
const auto& conditional_code = conditional->GetCode();
auto [found, internal_cursor] = FindOperation(
conditional_code, static_cast<s64>(conditional_code.size() - 1), operation_code);
if (found) {
return {std::move(found), cursor};
}
}
}
return {};
}
} // Anonymous namespace
std::tuple<Node, u32, u32> ShaderIR::TrackCbuf(Node tracked, const NodeBlock& code,
s64 cursor) const {
if (const auto cbuf = std::get_if<CbufNode>(&*tracked)) {
// Constant buffer found, test if it's an immediate
const auto offset = cbuf->GetOffset();
if (const auto immediate = std::get_if<ImmediateNode>(&*offset)) {
return {tracked, cbuf->GetIndex(), immediate->GetValue()};
}
return {};
}
if (const auto gpr = std::get_if<GprNode>(&*tracked)) {
if (gpr->GetIndex() == Tegra::Shader::Register::ZeroIndex) {
return {};
}
// Reduce the cursor in one to avoid infinite loops when the instruction sets the same
// register that it uses as operand
const auto [source, new_cursor] = TrackRegister(gpr, code, cursor - 1);
if (!source) {
return {};
}
return TrackCbuf(source, code, new_cursor);
}
if (const auto operation = std::get_if<OperationNode>(&*tracked)) {
for (std::size_t i = 0; i < operation->GetOperandsCount(); ++i) {
if (auto found = TrackCbuf((*operation)[i], code, cursor); std::get<0>(found)) {
// Cbuf found in operand.
return found;
}
}
return {};
}
if (const auto conditional = std::get_if<ConditionalNode>(&*tracked)) {
const auto& conditional_code = conditional->GetCode();
return TrackCbuf(tracked, conditional_code, static_cast<s64>(conditional_code.size()));
}
return {};
}
std::optional<u32> ShaderIR::TrackImmediate(Node tracked, const NodeBlock& code, s64 cursor) const {
// Reduce the cursor in one to avoid infinite loops when the instruction sets the same register
// that it uses as operand
const auto [found, found_cursor] =
TrackRegister(&std::get<GprNode>(*tracked), code, cursor - 1);
if (!found) {
return {};
}
if (const auto immediate = std::get_if<ImmediateNode>(&*found)) {
return immediate->GetValue();
}
return {};
}
std::pair<Node, s64> ShaderIR::TrackRegister(const GprNode* tracked, const NodeBlock& code,
s64 cursor) const {
for (; cursor >= 0; --cursor) {
const auto [found_node, new_cursor] = FindOperation(code, cursor, OperationCode::Assign);
if (!found_node) {
return {};
}
const auto operation = std::get_if<OperationNode>(&*found_node);
ASSERT(operation);
const auto& target = (*operation)[0];
if (const auto gpr_target = std::get_if<GprNode>(&*target)) {
if (gpr_target->GetIndex() == tracked->GetIndex()) {
return {(*operation)[1], new_cursor};
}
}
}
return {};
}
} // namespace VideoCommon::Shader