Merge pull request #1927 from ReinUsesLisp/shader-ir

video_core: Replace gl_shader_decompiler with an IR based decompiler

1 files changed, 67 insertions, 0 deletions

diff --git a/src/video_core/shader/decode/half_set.cpp b/src/video_core/shader/decode/half_set.cpp
new file mode 100644
index 000000000..dfd7cb98f
--- /dev/null
+++ b/src/video_core/shader/decode/half_set.cpp
@@ -0,0 +1,67 @@
+// Copyright 2018 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <array>
+
+#include "common/assert.h"
+#include "common/common_types.h"
+#include "video_core/engines/shader_bytecode.h"
+#include "video_core/shader/shader_ir.h"
+
+namespace VideoCommon::Shader {
+
+using Tegra::Shader::Instruction;
+using Tegra::Shader::OpCode;
+
+u32 ShaderIR::DecodeHalfSet(BasicBlock& bb, const BasicBlock& code, u32 pc) {
+    const Instruction instr = {program_code[pc]};
+    const auto opcode = OpCode::Decode(instr);
+
+    UNIMPLEMENTED_IF(instr.hset2.ftz != 0);
+
+    // instr.hset2.type_a
+    // instr.hset2.type_b
+    Node op_a = GetRegister(instr.gpr8);
+    Node op_b = [&]() {
+        switch (opcode->get().GetId()) {
+        case OpCode::Id::HSET2_R:
+            return GetRegister(instr.gpr20);
+        default:
+            UNREACHABLE();
+            return Immediate(0);
+        }
+    }();
+
+    op_a = GetOperandAbsNegHalf(op_a, instr.hset2.abs_a, instr.hset2.negate_a);
+    op_b = GetOperandAbsNegHalf(op_b, instr.hset2.abs_b, instr.hset2.negate_b);
+
+    const Node second_pred = GetPredicate(instr.hset2.pred39, instr.hset2.neg_pred);
+
+    MetaHalfArithmetic meta{false, {instr.hset2.type_a, instr.hset2.type_b}};
+    const Node comparison_pair = GetPredicateComparisonHalf(instr.hset2.cond, meta, op_a, op_b);
+
+    const OperationCode combiner = GetPredicateCombiner(instr.hset2.op);
+
+    // HSET2 operates on each half float in the pack.
+    std::array<Node, 2> values;
+    for (u32 i = 0; i < 2; ++i) {
+        const u32 raw_value = instr.hset2.bf ? 0x3c00 : 0xffff;
+        const Node true_value = Immediate(raw_value << (i * 16));
+        const Node false_value = Immediate(0);
+
+        const Node comparison =
+            Operation(OperationCode::LogicalPick2, comparison_pair, Immediate(i));
+        const Node predicate = Operation(combiner, comparison, second_pred);
+
+        values[i] =
+            Operation(OperationCode::Select, NO_PRECISE, predicate, true_value, false_value);
+    }
+
+    const Node value = Operation(OperationCode::UBitwiseOr, NO_PRECISE, values[0], values[1]);
+    SetRegister(bb, instr.gpr0, value);
+
+    return pc;
+}
+
+} // namespace VideoCommon::Shader
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