From 6c4cc0cd062fbbba5349da1108d3c23cb330ca8a Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Tue, 2 Feb 2021 21:07:00 -0300
Subject: shader: SSA and dominance

---
 src/shader_recompiler/frontend/maxwell/program.cpp | 75 +++++++++++++---------
 1 file changed, 44 insertions(+), 31 deletions(-)

(limited to 'src/shader_recompiler/frontend/maxwell/program.cpp')

diff --git a/src/shader_recompiler/frontend/maxwell/program.cpp b/src/shader_recompiler/frontend/maxwell/program.cpp
index 67a98ba57..49d1f4bfb 100644
--- a/src/shader_recompiler/frontend/maxwell/program.cpp
+++ b/src/shader_recompiler/frontend/maxwell/program.cpp
@@ -8,40 +8,53 @@
 #include "shader_recompiler/frontend/maxwell/program.h"
 #include "shader_recompiler/frontend/maxwell/termination_code.h"
 #include "shader_recompiler/frontend/maxwell/translate/translate.h"
+#include "shader_recompiler/ir_opt/passes.h"
 
 namespace Shader::Maxwell {
+namespace {
+void TranslateCode(Environment& env, const Flow::Function& cfg_function, IR::Function& function,
+                   std::span<IR::Block*> block_map, IR::Block* block_memory) {
+    const size_t num_blocks{cfg_function.blocks.size()};
+    function.blocks.reserve(num_blocks);
 
-Program::Function::~Function() {
-    std::ranges::for_each(blocks, &std::destroy_at<IR::Block>);
-}
-
-Program::Program(Environment& env, const Flow::CFG& cfg) {
-    std::vector<IR::Block*> block_map;
-    functions.reserve(cfg.Functions().size());
+    for (const Flow::BlockId block_id : cfg_function.blocks) {
+        const Flow::Block& flow_block{cfg_function.blocks_data[block_id]};
 
-    for (const Flow::Function& cfg_function : cfg.Functions()) {
-        Function& function{functions.emplace_back()};
+        function.blocks.emplace_back(std::construct_at(block_memory, Translate(env, flow_block)));
+        block_map[flow_block.id] = function.blocks.back().get();
+        ++block_memory;
+    }
+}
 
-        const size_t num_blocks{cfg_function.blocks.size()};
-        IR::Block* block_memory{block_alloc_pool.allocate(num_blocks)};
-        function.blocks.reserve(num_blocks);
+void EmitTerminationInsts(const Flow::Function& cfg_function,
+                          std::span<IR::Block* const> block_map) {
+    for (const Flow::BlockId block_id : cfg_function.blocks) {
+        const Flow::Block& flow_block{cfg_function.blocks_data[block_id]};
+        EmitTerminationCode(flow_block, block_map);
+    }
+}
 
-        block_map.resize(cfg_function.blocks_data.size());
+void TranslateFunction(Environment& env, const Flow::Function& cfg_function, IR::Function& function,
+                       IR::Block* block_memory) {
+    std::vector<IR::Block*> block_map;
+    block_map.resize(cfg_function.blocks_data.size());
 
-        // Visit the instructions of all blocks
-        for (const Flow::BlockId block_id : cfg_function.blocks) {
-            const Flow::Block& flow_block{cfg_function.blocks_data[block_id]};
+    TranslateCode(env, cfg_function, function, block_map, block_memory);
+    EmitTerminationInsts(cfg_function, block_map);
+}
+} // Anonymous namespace
 
-            IR::Block* const block{std::construct_at(block_memory, Translate(env, flow_block))};
-            ++block_memory;
-            function.blocks.push_back(block);
-            block_map[flow_block.id] = block;
-        }
-        // Now that all blocks are defined, emit the termination instructions
-        for (const Flow::BlockId block_id : cfg_function.blocks) {
-            const Flow::Block& flow_block{cfg_function.blocks_data[block_id]};
-            EmitTerminationCode(flow_block, block_map);
-        }
+Program::Program(Environment& env, const Flow::CFG& cfg) {
+    functions.reserve(cfg.Functions().size());
+    for (const Flow::Function& cfg_function : cfg.Functions()) {
+        TranslateFunction(env, cfg_function, functions.emplace_back(),
+                          block_alloc_pool.allocate(cfg_function.blocks.size()));
+    }
+    std::ranges::for_each(functions, Optimization::SsaRewritePass);
+    for (IR::Function& function : functions) {
+        Optimization::Invoke(Optimization::DeadCodeEliminationPass, function);
+        Optimization::Invoke(Optimization::IdentityRemovalPass, function);
+        // Optimization::Invoke(Optimization::VerificationPass, function);
     }
 }
 
@@ -50,16 +63,16 @@ std::string DumpProgram(const Program& program) {
     std::map<const IR::Inst*, size_t> inst_to_index;
     std::map<const IR::Block*, size_t> block_to_index;
 
-    for (const Program::Function& function : program.functions) {
-        for (const IR::Block* const block : function.blocks) {
-            block_to_index.emplace(block, index);
+    for (const IR::Function& function : program.functions) {
+        for (const auto& block : function.blocks) {
+            block_to_index.emplace(block.get(), index);
             ++index;
         }
     }
     std::string ret;
-    for (const Program::Function& function : program.functions) {
+    for (const IR::Function& function : program.functions) {
         ret += fmt::format("Function\n");
-        for (const IR::Block* const block : function.blocks) {
+        for (const auto& block : function.blocks) {
             ret += IR::DumpBlock(*block, block_to_index, inst_to_index, index) + '\n';
         }
     }
-- 
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