Merge pull request #6585 from ameerj/hades

Shader Decompiler Rewrite

1 files changed, 186 insertions, 0 deletions

diff --git a/src/shader_recompiler/backend/glasm/reg_alloc.cpp b/src/shader_recompiler/backend/glasm/reg_alloc.cpp
new file mode 100644
index 000000000..4c046db6e
--- /dev/null
+++ b/src/shader_recompiler/backend/glasm/reg_alloc.cpp
@@ -0,0 +1,186 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <string>
+
+#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 {
+
+Register RegAlloc::Define(IR::Inst& inst) {
+    return Define(inst, false);
+}
+
+Register RegAlloc::LongDefine(IR::Inst& inst) {
+    return Define(inst, true);
+}
+
+Value RegAlloc::Peek(const IR::Value& value) {
+    if (value.IsImmediate()) {
+        return MakeImm(value);
+    } else {
+        return PeekInst(*value.Inst());
+    }
+}
+
+Value RegAlloc::Consume(const IR::Value& value) {
+    if (value.IsImmediate()) {
+        return MakeImm(value);
+    } else {
+        return ConsumeInst(*value.Inst());
+    }
+}
+
+void RegAlloc::Unref(IR::Inst& inst) {
+    IR::Inst& value_inst{AliasInst(inst)};
+    value_inst.DestructiveRemoveUsage();
+    if (!value_inst.HasUses()) {
+        Free(value_inst.Definition<Id>());
+    }
+}
+
+Register RegAlloc::AllocReg() {
+    Register ret;
+    ret.type = Type::Register;
+    ret.id = Alloc(false);
+    return ret;
+}
+
+Register RegAlloc::AllocLongReg() {
+    Register ret;
+    ret.type = Type::Register;
+    ret.id = Alloc(true);
+    return ret;
+}
+
+void RegAlloc::FreeReg(Register reg) {
+    Free(reg.id);
+}
+
+Value RegAlloc::MakeImm(const IR::Value& value) {
+    Value ret;
+    switch (value.Type()) {
+    case IR::Type::Void:
+        ret.type = Type::Void;
+        break;
+    case IR::Type::U1:
+        ret.type = Type::U32;
+        ret.imm_u32 = value.U1() ? 0xffffffff : 0;
+        break;
+    case IR::Type::U32:
+        ret.type = Type::U32;
+        ret.imm_u32 = value.U32();
+        break;
+    case IR::Type::F32:
+        ret.type = Type::U32;
+        ret.imm_u32 = Common::BitCast<u32>(value.F32());
+        break;
+    case IR::Type::U64:
+        ret.type = Type::U64;
+        ret.imm_u64 = value.U64();
+        break;
+    case IR::Type::F64:
+        ret.type = Type::U64;
+        ret.imm_u64 = Common::BitCast<u64>(value.F64());
+        break;
+    default:
+        throw NotImplementedException("Immediate type {}", value.Type());
+    }
+    return ret;
+}
+
+Register RegAlloc::Define(IR::Inst& inst, bool is_long) {
+    if (inst.HasUses()) {
+        inst.SetDefinition<Id>(Alloc(is_long));
+    } else {
+        Id id{};
+        id.is_long.Assign(is_long ? 1 : 0);
+        id.is_null.Assign(1);
+        inst.SetDefinition<Id>(id);
+    }
+    return Register{PeekInst(inst)};
+}
+
+Value RegAlloc::PeekInst(IR::Inst& inst) {
+    Value ret;
+    ret.type = Type::Register;
+    ret.id = inst.Definition<Id>();
+    return ret;
+}
+
+Value RegAlloc::ConsumeInst(IR::Inst& inst) {
+    Unref(inst);
+    return PeekInst(inst);
+}
+
+Id RegAlloc::Alloc(bool is_long) {
+    size_t& num_regs{is_long ? num_used_long_registers : num_used_registers};
+    std::bitset<NUM_REGS>& use{is_long ? long_register_use : register_use};
+    if (num_used_registers + num_used_long_registers < NUM_REGS) {
+        for (size_t reg = 0; reg < NUM_REGS; ++reg) {
+            if (use[reg]) {
+                continue;
+            }
+            num_regs = std::max(num_regs, reg + 1);
+            use[reg] = true;
+            Id ret{};
+            ret.is_valid.Assign(1);
+            ret.is_long.Assign(is_long ? 1 : 0);
+            ret.is_spill.Assign(0);
+            ret.is_condition_code.Assign(0);
+            ret.is_null.Assign(0);
+            ret.index.Assign(static_cast<u32>(reg));
+            return ret;
+        }
+    }
+    throw NotImplementedException("Register spilling");
+}
+
+void RegAlloc::Free(Id id) {
+    if (id.is_valid == 0) {
+        throw LogicError("Freeing invalid register");
+    }
+    if (id.is_spill != 0) {
+        throw NotImplementedException("Free spill");
+    }
+    if (id.is_long != 0) {
+        long_register_use[id.index] = false;
+    } else {
+        register_use[id.index] = false;
+    }
+}
+
+/*static*/ bool RegAlloc::IsAliased(const IR::Inst& inst) {
+    switch (inst.GetOpcode()) {
+    case IR::Opcode::Identity:
+    case IR::Opcode::BitCastU16F16:
+    case IR::Opcode::BitCastU32F32:
+    case IR::Opcode::BitCastU64F64:
+    case IR::Opcode::BitCastF16U16:
+    case IR::Opcode::BitCastF32U32:
+    case IR::Opcode::BitCastF64U64:
+        return true;
+    default:
+        return false;
+    }
+}
+
+/*static*/ IR::Inst& RegAlloc::AliasInst(IR::Inst& inst) {
+    IR::Inst* it{&inst};
+    while (IsAliased(*it)) {
+        const IR::Value arg{it->Arg(0)};
+        if (arg.IsImmediate()) {
+            break;
+        }
+        it = arg.InstRecursive();
+    }
+    return *it;
+}
+
+} // namespace Shader::Backend::GLASM