glasm: Changes to GLASM register allocator and emit context

src/shader_recompiler/backend/glasm/emit_context.cpp

@@ -2,6 +2,10 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#pragma once
-
 #include "shader_recompiler/backend/glasm/emit_context.h"
+
+namespace Shader::Backend::GLASM {
+
+EmitContext::EmitContext() = default;
+
+} // namespace Shader::Backend::GLASM

src/shader_recompiler/backend/glasm/emit_context.h

@@ -5,17 +5,38 @@
 #pragma once
 
 #include <string>
+#include <utility>
+
+#include <fmt/format.h>
 
 #include "shader_recompiler/backend/glasm/reg_alloc.h"
 
+namespace Shader::IR {
+class Inst;
+}
+
 namespace Shader::Backend::GLASM {
 
 class EmitContext {
 public:
-    std::string code;
-    RegAlloc reg_alloc;
+    explicit EmitContext();
 
-private:
+    template <typename... Args>
+    void Add(const char* fmt, IR::Inst& inst, Args&&... args) {
+        code += fmt::format(fmt, reg_alloc.Define(inst), std::forward<Args>(args)...);
+        // TODO: Remove this
+        code += '\n';
+    }
+
+    template <typename... Args>
+    void Add(const char* fmt, Args&&... args) {
+        code += fmt::format(fmt, std::forward<Args>(args)...);
+        // TODO: Remove this
+        code += '\n';
+    }
+
+    std::string code;
+    RegAlloc reg_alloc{*this};
 };
 
 } // namespace Shader::Backend::GLASM

src/shader_recompiler/backend/glasm/reg_alloc.cpp

@@ -3,18 +3,16 @@
 // Refer to the license.txt file included.
 
 #include <string>
-#include <string_view>
 
 #include <fmt/format.h>
 
+#include "shader_recompiler/backend/glasm/emit_context.h"
 #include "shader_recompiler/backend/glasm/reg_alloc.h"
 #include "shader_recompiler/exception.h"
 #include "shader_recompiler/frontend/ir/value.h"
 
 namespace Shader::Backend::GLASM {
 namespace {
-constexpr std::string_view SWIZZLE = "xyzw";
-
 std::string Representation(Id id) {
     if (id.is_condition_code != 0) {
         throw NotImplementedException("Condition code");
@@ -22,27 +20,36 @@ std::string Representation(Id id) {
     if (id.is_spill != 0) {
         throw NotImplementedException("Spilling");
     }
-    const u32 num_elements{id.num_elements_minus_one + 1};
     const u32 index{static_cast<u32>(id.index)};
-    if (num_elements == 4) {
-        return fmt::format("R{}", index);
-    } else {
-        return fmt::format("R{}.{}", index, SWIZZLE.substr(id.base_element, num_elements));
+    return fmt::format("R{}.x", index);
+}
+
+std::string ImmValue(const IR::Value& value) {
+    switch (value.Type()) {
+    case IR::Type::U1:
+        return value.U1() ? "-1" : "0";
+    case IR::Type::U32:
+        return fmt::format("{}", value.U32());
+    case IR::Type::F32:
+        return fmt::format("{}", value.F32());
+    default:
+        throw NotImplementedException("Immediate type", value.Type());
     }
 }
 } // Anonymous namespace
 
-std::string RegAlloc::Define(IR::Inst& inst, u32 num_elements, u32 alignment) {
-    const Id id{Alloc(num_elements, alignment)};
+std::string RegAlloc::Define(IR::Inst& inst) {
+    const Id id{Alloc()};
     inst.SetDefinition<Id>(id);
     return Representation(id);
 }
 
 std::string RegAlloc::Consume(const IR::Value& value) {
-    if (!value.IsImmediate()) {
-        return Consume(*value.Inst());
+    if (value.IsImmediate()) {
+        return ImmValue(value);
+    } else {
+        return Consume(*value.InstRecursive());
     }
-    throw NotImplementedException("Immediate loading");
 }
 
 std::string RegAlloc::Consume(IR::Inst& inst) {
@@ -54,7 +61,7 @@ std::string RegAlloc::Consume(IR::Inst& inst) {
     return Representation(inst.Definition<Id>());
 }
 
-Id RegAlloc::Alloc(u32 num_elements, [[maybe_unused]] u32 alignment) {
+Id RegAlloc::Alloc() {
     for (size_t reg = 0; reg < NUM_REGS; ++reg) {
         if (register_use[reg]) {
             continue;
@@ -62,8 +69,6 @@ Id RegAlloc::Alloc(u32 num_elements, [[maybe_unused]] u32 alignment) {
         num_used_registers = std::max(num_used_registers, reg + 1);
         register_use[reg] = true;
         return Id{
-            .base_element = 0,
-            .num_elements_minus_one = num_elements - 1,
             .index = static_cast<u32>(reg),
             .is_spill = 0,
             .is_condition_code = 0,

src/shader_recompiler/backend/glasm/reg_alloc.h

@@ -15,27 +15,35 @@ class Value;
 
 namespace Shader::Backend::GLASM {
 
+class EmitContext;
+
 struct Id {
-    u32 base_element : 2;
-    u32 num_elements_minus_one : 2;
-    u32 index : 26;
+    u32 index : 30;
     u32 is_spill : 1;
     u32 is_condition_code : 1;
 };
 
 class RegAlloc {
 public:
-    std::string Define(IR::Inst& inst, u32 num_elements = 1, u32 alignment = 1);
+    RegAlloc(EmitContext& ctx_) : ctx{ctx_} {}
+
+    std::string Define(IR::Inst& inst);
 
     std::string Consume(const IR::Value& value);
 
+    [[nodiscard]] size_t NumUsedRegisters() const noexcept {
+        return num_used_registers;
+    }
+
 private:
     static constexpr size_t NUM_REGS = 4096;
     static constexpr size_t NUM_ELEMENTS = 4;
 
+    EmitContext& ctx;
+
     std::string Consume(IR::Inst& inst);
 
-    Id Alloc(u32 num_elements, u32 alignment);
+    Id Alloc();
 
     void Free(Id id);