5 files changed, 68 insertions, 12 deletions

diff --git a/src/shader_recompiler/frontend/ir/ir_emitter.cpp b/src/shader_recompiler/frontend/ir/ir_emitter.cpp
index 0209d5540..7c3908398 100644
--- a/src/shader_recompiler/frontend/ir/ir_emitter.cpp
+++ b/src/shader_recompiler/frontend/ir/ir_emitter.cpp
@@ -804,6 +804,10 @@ U32 IREmitter::BitFieldExtract(const U32& base, const U32& offset, const U32& co
                      count);
 }
 
+U32 IREmitter::BitReverse(const U32& value) {
+    return Inst<U32>(Opcode::BitReverse32, value);
+}
+
 U1 IREmitter::ILessThan(const U32& lhs, const U32& rhs, bool is_signed) {
     return Inst<U1>(is_signed ? Opcode::SLessThan : Opcode::ULessThan, lhs, rhs);
 }
diff --git a/src/shader_recompiler/frontend/ir/ir_emitter.h b/src/shader_recompiler/frontend/ir/ir_emitter.h
index 2c923716a..f7998e156 100644
--- a/src/shader_recompiler/frontend/ir/ir_emitter.h
+++ b/src/shader_recompiler/frontend/ir/ir_emitter.h
@@ -159,6 +159,7 @@ public:
                                      const U32& count);
     [[nodiscard]] U32 BitFieldExtract(const U32& base, const U32& offset, const U32& count,
                                       bool is_signed);
+    [[nodiscard]] U32 BitReverse(const U32& value);
 
     [[nodiscard]] U1 ILessThan(const U32& lhs, const U32& rhs, bool is_signed);
     [[nodiscard]] U1 IEqual(const U32& lhs, const U32& rhs);
diff --git a/src/shader_recompiler/frontend/ir/opcodes.inc b/src/shader_recompiler/frontend/ir/opcodes.inc
index 289e76f32..f420f1161 100644
--- a/src/shader_recompiler/frontend/ir/opcodes.inc
+++ b/src/shader_recompiler/frontend/ir/opcodes.inc
@@ -231,6 +231,7 @@ OPCODE(BitwiseXor32,                                        U32,            U32,
 OPCODE(BitFieldInsert,                                      U32,            U32,            U32,            U32,            U32,            )
 OPCODE(BitFieldSExtract,                                    U32,            U32,            U32,            U32,                            )
 OPCODE(BitFieldUExtract,                                    U32,            U32,            U32,            U32,                            )
+OPCODE(BitReverse32,                                        U32,            U32,                                                            )
 
 OPCODE(SLessThan,                                           U1,             U32,            U32,                                            )
 OPCODE(ULessThan,                                           U1,             U32,            U32,                                            )
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/integer_shift_right.cpp b/src/shader_recompiler/frontend/maxwell/translate/impl/integer_shift_right.cpp
new file mode 100644
index 000000000..a34ccb851
--- /dev/null
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/integer_shift_right.cpp
@@ -0,0 +1,62 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/bit_field.h"
+#include "common/common_types.h"
+#include "shader_recompiler/frontend/maxwell/translate/impl/impl.h"
+
+namespace Shader::Maxwell {
+namespace {
+void SHR(TranslatorVisitor& v, u64 insn, const IR::U32& shift) {
+    union {
+        u64 insn;
+        BitField<0, 8, IR::Reg> dest_reg;
+        BitField<8, 8, IR::Reg> src_reg_a;
+        BitField<39, 1, u64> is_wrapped;
+        BitField<40, 1, u64> brev;
+        BitField<43, 1, u64> xmode;
+        BitField<48, 1, u64> is_arithmetic;
+    } const shr{insn};
+
+    if (shr.xmode != 0) {
+        throw NotImplementedException("SHR.XMODE");
+    }
+
+    IR::U32 base{v.X(shr.src_reg_a)};
+    if (shr.brev == 1) {
+        base = v.ir.BitReverse(base);
+    }
+    IR::U32 result;
+    const IR::U32 safe_shift = shr.is_wrapped == 0 ? shift : v.ir.BitwiseAnd(shift, v.ir.Imm32(31));
+    if (shr.is_arithmetic == 1) {
+        result = IR::U32{v.ir.ShiftRightArithmetic(base, safe_shift)};
+    } else {
+        result = IR::U32{v.ir.ShiftRightLogical(base, safe_shift)};
+    }
+
+    if (shr.is_wrapped == 0) {
+        const IR::U32 zero{v.ir.Imm32(0)};
+        const IR::U32 safe_bits{v.ir.Imm32(32)};
+
+        const IR::U1 is_negative{v.ir.ILessThan(result, zero, true)};
+        const IR::U1 is_safe{v.ir.ILessThan(shift, safe_bits, false)};
+        const IR::U32 clamped_value{v.ir.Select(is_negative, v.ir.Imm32(-1), zero)};
+        result = IR::U32{v.ir.Select(is_safe, result, clamped_value)};
+    }
+    v.X(shr.dest_reg, result);
+}
+} // Anonymous namespace
+
+void TranslatorVisitor::SHR_reg(u64 insn) {
+    SHR(*this, insn, GetReg20(insn));
+}
+
+void TranslatorVisitor::SHR_cbuf(u64 insn) {
+    SHR(*this, insn, GetCbuf(insn));
+}
+
+void TranslatorVisitor::SHR_imm(u64 insn) {
+    SHR(*this, insn, GetImm20(insn));
+}
+} // namespace Shader::Maxwell
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp b/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
index 82c73bf8c..45ed04e25 100644
--- a/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
@@ -757,18 +757,6 @@ void TranslatorVisitor::SHFL(u64) {
     ThrowNotImplemented(Opcode::SHFL);
 }
 
-void TranslatorVisitor::SHR_reg(u64) {
-    ThrowNotImplemented(Opcode::SHR_reg);
-}
-
-void TranslatorVisitor::SHR_cbuf(u64) {
-    ThrowNotImplemented(Opcode::SHR_cbuf);
-}
-
-void TranslatorVisitor::SHR_imm(u64) {
-    ThrowNotImplemented(Opcode::SHR_imm);
-}
-
 void TranslatorVisitor::SSY() {
     // SSY is a no-op
 }