Merge pull request #344 from bunnei/shader-decompiler-p2

Shader decompiler changes part 2

src/video_core/engines/shader_bytecode.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <cstring>
 #include <map>
 #include <string>
 #include "common/bit_field.h"
@@ -12,14 +13,10 @@ namespace Tegra {
 namespace Shader {
 
 struct Register {
-    Register() = default;
+    constexpr Register() = default;
 
     constexpr Register(u64 value) : value(value) {}
 
-    constexpr u64 GetIndex() const {
-        return value;
-    }
-
     constexpr operator u64() const {
         return value;
     }
@@ -43,13 +40,13 @@ struct Register {
     }
 
 private:
-    u64 value;
+    u64 value{};
 };
 
 union Attribute {
     Attribute() = default;
 
-    constexpr Attribute(u64 value) : value(value) {}
+    constexpr explicit Attribute(u64 value) : value(value) {}
 
     enum class Index : u64 {
         Position = 7,
@@ -68,7 +65,20 @@ union Attribute {
     } fmt28;
 
     BitField<39, 8, u64> reg;
-    u64 value;
+    u64 value{};
+};
+
+union Sampler {
+    Sampler() = default;
+
+    constexpr explicit Sampler(u64 value) : value(value) {}
+
+    enum class Index : u64 {
+        Sampler_0 = 8,
+    };
+
+    BitField<36, 13, Index> index;
+    u64 value{};
 };
 
 union Uniform {
@@ -238,7 +248,7 @@ union OpCode {
     BitField<55, 9, Id> op3;
     BitField<52, 12, Id> op4;
     BitField<51, 13, Id> op5;
-    u64 value;
+    u64 value{};
 };
 static_assert(sizeof(OpCode) == 0x8, "Incorrect structure size");
 
@@ -280,6 +290,7 @@ enum class SubOp : u64 {
     Lg2 = 0x3,
     Rcp = 0x4,
     Rsq = 0x5,
+    Min = 0x8,
 };
 
 union Instruction {
@@ -295,15 +306,25 @@ union Instruction {
     BitField<20, 8, Register> gpr20;
     BitField<20, 7, SubOp> sub_op;
     BitField<28, 8, Register> gpr28;
-    BitField<36, 13, u64> imm36;
     BitField<39, 8, Register> gpr39;
 
     union {
+        BitField<20, 19, u64> imm20;
         BitField<45, 1, u64> negate_b;
         BitField<46, 1, u64> abs_a;
         BitField<48, 1, u64> negate_a;
         BitField<49, 1, u64> abs_b;
         BitField<50, 1, u64> abs_d;
+        BitField<56, 1, u64> negate_imm;
+
+        float GetImm20() const {
+            float result{};
+            u32 imm{static_cast<u32>(imm20)};
+            imm <<= 12;
+            imm |= negate_imm ? 0x80000000 : 0;
+            std::memcpy(&result, &imm, sizeof(imm));
+            return result;
+        }
     } alu;
 
     union {
@@ -311,11 +332,13 @@ union Instruction {
         BitField<49, 1, u64> negate_c;
     } ffma;
 
+    BitField<61, 1, u64> is_b_imm;
     BitField<60, 1, u64> is_b_gpr;
     BitField<59, 1, u64> is_c_gpr;
 
     Attribute attribute;
     Uniform uniform;
+    Sampler sampler;
 
     u64 hex;
 };