From 6312eec5ef650ca5363ef4cfa08c2d38ffb6a0fe Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Mon, 15 Oct 2018 02:10:15 -0300
Subject: [PATCH] gl_shader_decompiler: Implement HSET2_R

---
 src/video_core/engines/shader_bytecode.h      | 18 ++++++++
 .../renderer_opengl/gl_shader_decompiler.cpp  | 44 +++++++++++++++++++
 2 files changed, 62 insertions(+)

diff --git a/src/video_core/engines/shader_bytecode.h b/src/video_core/engines/shader_bytecode.h
index a6e764ea4..39ae065de 100644
--- a/src/video_core/engines/shader_bytecode.h
+++ b/src/video_core/engines/shader_bytecode.h
@@ -831,6 +831,21 @@ union Instruction {
         BitField<56, 1, u64> neg_imm;
     } fset;
 
+    union {
+        BitField<49, 1, u64> bf;
+        BitField<35, 3, PredCondition> cond;
+        BitField<50, 1, u64> ftz;
+        BitField<45, 2, PredOperation> op;
+        BitField<43, 1, u64> negate_a;
+        BitField<44, 1, u64> abs_a;
+        BitField<47, 2, HalfType> type_a;
+        BitField<31, 1, u64> negate_b;
+        BitField<30, 1, u64> abs_b;
+        BitField<28, 2, HalfType> type_b;
+        BitField<42, 1, u64> neg_pred;
+        BitField<39, 3, u64> pred39;
+    } hset2;
+
     union {
         BitField<39, 3, u64> pred39;
         BitField<42, 1, u64> neg_pred;
@@ -1257,6 +1272,7 @@ public:
         HFMA2_RR,
         HFMA2_IMM_R,
         HSETP2_R,
+        HSET2_R,
         POPC_C,
         POPC_R,
         POPC_IMM,
@@ -1343,6 +1359,7 @@ public:
         FloatSetPredicate,
         IntegerSet,
         IntegerSetPredicate,
+        HalfSet,
         HalfSetPredicate,
         PredicateSetPredicate,
         PredicateSetRegister,
@@ -1516,6 +1533,7 @@ private:
             INST("0101110100000---", Id::HFMA2_RR, Type::Hfma2, "HFMA2_RR"),
             INST("01110---0-------", Id::HFMA2_IMM_R, Type::Hfma2, "HFMA2_R_IMM"),
             INST("0101110100100---", Id::HSETP2_R, Type::HalfSetPredicate, "HSETP_R"),
+            INST("0101110100011---", Id::HSET2_R, Type::HalfSet, "HSET2_R"),
             INST("0101000010000---", Id::MUFU, Type::Arithmetic, "MUFU"),
             INST("0100110010010---", Id::RRO_C, Type::Arithmetic, "RRO_C"),
             INST("0101110010010---", Id::RRO_R, Type::Arithmetic, "RRO_R"),
diff --git a/src/video_core/renderer_opengl/gl_shader_decompiler.cpp b/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
index 06f85fad2..23349b1a1 100644
--- a/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
@@ -2996,6 +2996,50 @@ private:
             }
             break;
         }
+        case OpCode::Type::HalfSet: {
+            ASSERT_MSG(instr.hset2.ftz == 0, "Unimplemented");
+
+            const std::string op_a =
+                GetHalfFloat(regs.GetRegisterAsInteger(instr.gpr8, 0, false), instr.hset2.type_a,
+                             instr.hset2.abs_a != 0, instr.hset2.negate_a != 0);
+
+            const std::string op_b = [&]() {
+                switch (opcode->GetId()) {
+                case OpCode::Id::HSET2_R:
+                    return GetHalfFloat(regs.GetRegisterAsInteger(instr.gpr20, 0, false),
+                                        instr.hset2.type_b, instr.hset2.abs_b != 0,
+                                        instr.hset2.negate_b != 0);
+                default:
+                    UNREACHABLE();
+                    return std::string("vec2(0)");
+                }
+            }();
+
+            const std::string second_pred =
+                GetPredicateCondition(instr.hset2.pred39, instr.hset2.neg_pred != 0);
+
+            const std::string combiner = GetPredicateCombiner(instr.hset2.op);
+
+            // HSET2 operates on each half float in the pack.
+            std::string result;
+            for (int i = 0; i < 2; ++i) {
+                const std::string float_value = i == 0 ? "0x00003c00" : "0x3c000000";
+                const std::string integer_value = i == 0 ? "0x0000ffff" : "0xffff0000";
+                const std::string value = instr.hset2.bf == 1 ? float_value : integer_value;
+
+                const std::string comp = std::string(".") + "xy"[i];
+                const std::string predicate =
+                    "((" + GetPredicateComparison(instr.hset2.cond, op_a + comp, op_b + comp) +
+                    ") " + combiner + " (" + second_pred + "))";
+
+                result += '(' + predicate + " ? " + value + " : 0)";
+                if (i == 0) {
+                    result += " | ";
+                }
+            }
+            regs.SetRegisterToInteger(instr.gpr0, false, 0, '(' + result + ')', 1, 1);
+            break;
+        }
         case OpCode::Type::Xmad: {
             ASSERT_MSG(!instr.xmad.sign_a, "Unimplemented");
             ASSERT_MSG(!instr.xmad.sign_b, "Unimplemented");