From c218ae4b022a9b47366e88441220fa6c66bcae4b Mon Sep 17 00:00:00 2001
From: Fernando Sahmkow <fsahmkow27@gmail.com>
Date: Mon, 24 Jun 2019 21:01:49 -0400
Subject: [PATCH] shader_ir: Remove the old scanner.
---
src/video_core/shader/decode.cpp | 66 -------------------------------
src/video_core/shader/shader_ir.h | 11 ------
2 files changed, 77 deletions(-)
diff --git a/src/video_core/shader/decode.cpp b/src/video_core/shader/decode.cpp
index 7f433c56b0..65029d35e7 100644
--- a/src/video_core/shader/decode.cpp
+++ b/src/video_core/shader/decode.cpp
@@ -22,20 +22,6 @@ using Tegra::Shader::OpCode;
namespace {
-/// Merges exit method of two parallel branches.
-constexpr ExitMethod ParallelExit(ExitMethod a, ExitMethod b) {
- if (a == ExitMethod::Undetermined) {
- return b;
- }
- if (b == ExitMethod::Undetermined) {
- return a;
- }
- if (a == b) {
- return a;
- }
- return ExitMethod::Conditional;
-}
-
/**
* Returns whether the instruction at the specified offset is a 'sched' instruction.
* Sched instructions always appear before a sequence of 3 instructions.
@@ -79,58 +65,6 @@ void ShaderIR::Decode() {
return;
}
-ExitMethod ShaderIR::Scan(u32 begin, u32 end, std::set<u32>& labels) {
- const auto [iter, inserted] =
- exit_method_map.emplace(std::make_pair(begin, end), ExitMethod::Undetermined);
- ExitMethod& exit_method = iter->second;
- if (!inserted)
- return exit_method;
-
- for (u32 offset = begin; offset != end && offset != MAX_PROGRAM_LENGTH; ++offset) {
- coverage_begin = std::min(coverage_begin, offset);
- coverage_end = std::max(coverage_end, offset + 1);
-
- const Instruction instr = {program_code[offset]};
- const auto opcode = OpCode::Decode(instr);
- if (!opcode)
- continue;
- switch (opcode->get().GetId()) {
- case OpCode::Id::EXIT: {
- // The EXIT instruction can be predicated, which means that the shader can conditionally
- // end on this instruction. We have to consider the case where the condition is not met
- // and check the exit method of that other basic block.
- using Tegra::Shader::Pred;
- if (instr.pred.pred_index == static_cast<u64>(Pred::UnusedIndex)) {
- return exit_method = ExitMethod::AlwaysEnd;
- } else {
- const ExitMethod not_met = Scan(offset + 1, end, labels);
- return exit_method = ParallelExit(ExitMethod::AlwaysEnd, not_met);
- }
- }
- case OpCode::Id::BRA: {
- const u32 target = offset + instr.bra.GetBranchTarget();
- labels.insert(target);
- const ExitMethod no_jmp = Scan(offset + 1, end, labels);
- const ExitMethod jmp = Scan(target, end, labels);
- return exit_method = ParallelExit(no_jmp, jmp);
- }
- case OpCode::Id::SSY:
- case OpCode::Id::PBK: {
- // The SSY and PBK use a similar encoding as the BRA instruction.
- UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
- "Constant buffer branching is not supported");
- const u32 target = offset + instr.bra.GetBranchTarget();
- labels.insert(target);
- // Continue scanning for an exit method.
- break;
- }
- default:
- break;
- }
- }
- return exit_method = ExitMethod::AlwaysReturn;
-}
-
NodeBlock ShaderIR::DecodeRange(u32 begin, u32 end) {
NodeBlock basic_block;
for (u32 pc = begin; pc < (begin > end ? MAX_PROGRAM_LENGTH : end);) {
diff --git a/src/video_core/shader/shader_ir.h b/src/video_core/shader/shader_ir.h
index e225482081..e71462e024 100644
--- a/src/video_core/shader/shader_ir.h
+++ b/src/video_core/shader/shader_ir.h
@@ -26,14 +26,6 @@ using ProgramCode = std::vector<u64>;
constexpr u32 MAX_PROGRAM_LENGTH = 0x1000;
-/// Describes the behaviour of code path of a given entry point and a return point.
-enum class ExitMethod {
- Undetermined, ///< Internal value. Only occur when analyzing JMP loop.
- AlwaysReturn, ///< All code paths reach the return point.
- Conditional, ///< Code path reaches the return point or an END instruction conditionally.
- AlwaysEnd, ///< All code paths reach a END instruction.
-};
-
class ConstBuffer {
public:
explicit ConstBuffer(u32 max_offset, bool is_indirect)
@@ -132,8 +124,6 @@ public:
private:
void Decode();
- ExitMethod Scan(u32 begin, u32 end, std::set<u32>& labels);
-
NodeBlock DecodeRange(u32 begin, u32 end);
/**
@@ -329,7 +319,6 @@ private:
u32 coverage_begin{};
u32 coverage_end{};
- std::map<std::pair<u32, u32>, ExitMethod> exit_method_map;
std::map<u32, NodeBlock> basic_blocks;
NodeBlock global_code;