shader_ir: Implement BRX & BRA.CC

3 files changed, 42 insertions, 4 deletions

diff --git a/src/video_core/shader/control_flow.cpp b/src/video_core/shader/control_flow.cpp
index fcf22c7f2..a9de8f814 100644
--- a/src/video_core/shader/control_flow.cpp
+++ b/src/video_core/shader/control_flow.cpp
@@ -284,6 +284,9 @@ ParseResult ParseCode(CFGRebuildState& state, u32 address, ParseInfo& parse_info
             state.pbk_labels.emplace(offset, target);
             break;
         }
+        case OpCode::Id::BRX: {
+            return ParseResult::AbnormalFlow;
+        }
         default:
             break;
         }
diff --git a/src/video_core/shader/decode/other.cpp b/src/video_core/shader/decode/other.cpp
index d46a8ab82..ed3c63781 100644
--- a/src/video_core/shader/decode/other.cpp
+++ b/src/video_core/shader/decode/other.cpp
@@ -91,11 +91,45 @@ u32 ShaderIR::DecodeOther(NodeBlock& bb, u32 pc) {
         break;
     }
     case OpCode::Id::BRA: {
-        UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
-                             "BRA with constant buffers are not implemented");
+        Node branch;
+        if (instr.bra.constant_buffer == 0) {
+            const u32 target = pc + instr.bra.GetBranchTarget();
+            branch = Operation(OperationCode::Branch, Immediate(target));
+        } else {
+            const u32 target = pc + 1;
+            const Node op_a = GetConstBuffer(instr.cbuf36.index, instr.cbuf36.GetOffset());
+            const Node convert = SignedOperation(OperationCode::IArithmeticShiftRight,
+                                               true, PRECISE, op_a, Immediate(3));
+            const Node operand = Operation(OperationCode::IAdd, PRECISE, convert, Immediate(target));
+            branch = Operation(OperationCode::BranchIndirect, convert);
+        }
 
-        const u32 target = pc + instr.bra.GetBranchTarget();
-        const Node branch = Operation(OperationCode::Branch, Immediate(target));
+        const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
+        if (cc != Tegra::Shader::ConditionCode::T) {
+            bb.push_back(Conditional(GetConditionCode(cc), {branch}));
+        } else {
+            bb.push_back(branch);
+        }
+        break;
+    }
+    case OpCode::Id::BRX: {
+        Node operand;
+        if (instr.brx.constant_buffer != 0) {
+            const s32 target = pc + 1;
+            const Node index = GetRegister(instr.gpr8);
+            const Node op_a =
+                GetConstBufferIndirect(instr.cbuf36.index, instr.cbuf36.GetOffset() + 0, index);
+            const Node convert = SignedOperation(OperationCode::IArithmeticShiftRight,
+                                               true, PRECISE, op_a, Immediate(3));
+            operand = Operation(OperationCode::IAdd, PRECISE, convert, Immediate(target));
+        } else {
+            const s32 target = pc + instr.brx.GetBranchExtend();
+            const Node op_a = GetRegister(instr.gpr8);
+            const Node convert = SignedOperation(OperationCode::IArithmeticShiftRight,
+                                               true, PRECISE, op_a, Immediate(3));
+            operand = Operation(OperationCode::IAdd, PRECISE, convert, Immediate(target));
+        }
+        const Node branch = Operation(OperationCode::BranchIndirect, operand);
 
         const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
         if (cc != Tegra::Shader::ConditionCode::T) {
diff --git a/src/video_core/shader/node.h b/src/video_core/shader/node.h
index 0ac83fcf0..e468758a6 100644
--- a/src/video_core/shader/node.h
+++ b/src/video_core/shader/node.h
@@ -149,6 +149,7 @@ enum class OperationCode {
     ImageStore, /// (MetaImage, float[N] coords) -> void
 
     Branch,        /// (uint branch_target) -> void
+    BranchIndirect,/// (uint branch_target) -> void
     PushFlowStack, /// (uint branch_target) -> void
     PopFlowStack,  /// () -> void
     Exit,          /// () -> void