From f976c47008b5a21a87adabb6a08492ef597083b1 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Mon, 30 Jul 2018 13:31:51 +0100
Subject: [PATCH] IR: Initial implementation of FPVectorRoundInt

---
 .../emit_x64_vector_floating_point.cpp        | 50 +++++++++++++++++++
 src/frontend/ir/ir_emitter.cpp                | 11 ++++
 src/frontend/ir/ir_emitter.h                  |  1 +
 src/frontend/ir/opcodes.inc                   |  2 +
 4 files changed, 64 insertions(+)

diff --git a/src/backend_x64/emit_x64_vector_floating_point.cpp b/src/backend_x64/emit_x64_vector_floating_point.cpp
index 62629557..7a1c1d03 100644
--- a/src/backend_x64/emit_x64_vector_floating_point.cpp
+++ b/src/backend_x64/emit_x64_vector_floating_point.cpp
@@ -24,6 +24,7 @@
 #include "common/mp/list.h"
 #include "common/mp/lut.h"
 #include "common/mp/to_tuple.h"
+#include "common/mp/vlift.h"
 #include "common/mp/vllift.h"
 #include "frontend/ir/basic_block.h"
 #include "frontend/ir/microinstruction.h"
@@ -728,6 +729,55 @@ void EmitX64::EmitFPVectorRecipStepFused64(EmitContext& ctx, IR::Inst* inst) {
     EmitRecipStepFused<u64>(code, ctx, inst);
 }
 
+template<size_t fsize>
+void EmitFPVectorRoundInt(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst) {
+    using FPT = mp::unsigned_integer_of_size<fsize>;
+
+    const auto rounding = static_cast<FP::RoundingMode>(inst->GetArg(1).GetU8());
+    const bool exact = inst->GetArg(2).GetU1();
+
+    using rounding_list = mp::list<
+        std::integral_constant<FP::RoundingMode, FP::RoundingMode::ToNearest_TieEven>,
+        std::integral_constant<FP::RoundingMode, FP::RoundingMode::TowardsPlusInfinity>,
+        std::integral_constant<FP::RoundingMode, FP::RoundingMode::TowardsMinusInfinity>,
+        std::integral_constant<FP::RoundingMode, FP::RoundingMode::TowardsZero>,
+        std::integral_constant<FP::RoundingMode, FP::RoundingMode::ToNearest_TieAwayFromZero>
+    >;
+    using exact_list = mp::list<mp::vlift<true>, mp::vlift<false>>;
+
+    using key_type = std::tuple<FP::RoundingMode, bool>;
+    using value_type = void(*)(VectorArray<FPT>&, const VectorArray<FPT>&, FP::FPCR, FP::FPSR&);
+
+    static const auto lut = mp::GenerateLookupTableFromList<key_type, value_type>(
+        [](auto arg) {
+            return std::pair<key_type, value_type>{
+                mp::to_tuple<decltype(arg)>,
+                static_cast<value_type>(
+                    [](VectorArray<FPT>& output, const VectorArray<FPT>& input, FP::FPCR fpcr, FP::FPSR& fpsr) {
+                        constexpr FP::RoundingMode rounding_mode = std::get<0>(mp::to_tuple<decltype(arg)>);
+                        constexpr bool exact = std::get<1>(mp::to_tuple<decltype(arg)>);
+
+                        for (size_t i = 0; i < output.size(); ++i) {
+                            output[i] = static_cast<FPT>(FP::FPRoundInt<FPT>(input[i], fpcr, rounding_mode, exact, fpsr));
+                        }
+                    }
+                )
+            };
+        },
+        mp::cartesian_product<rounding_list, exact_list>{}
+    );
+
+    EmitTwoOpFallback(code, ctx, inst, lut.at(std::make_tuple(rounding, exact)));
+}
+
+void EmitX64::EmitFPVectorRoundInt32(EmitContext& ctx, IR::Inst* inst) {
+    EmitFPVectorRoundInt<32>(code, ctx, inst);
+}
+
+void EmitX64::EmitFPVectorRoundInt64(EmitContext& ctx, IR::Inst* inst) {
+    EmitFPVectorRoundInt<64>(code, ctx, inst);
+}
+
 template<typename FPT>
 static void EmitRSqrtEstimate(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst) {
     EmitTwoOpFallback(code, ctx, inst, [](VectorArray<FPT>& result, const VectorArray<FPT>& operand, FP::FPCR fpcr, FP::FPSR& fpsr) {
diff --git a/src/frontend/ir/ir_emitter.cpp b/src/frontend/ir/ir_emitter.cpp
index 98aad4c3..399af66d 100644
--- a/src/frontend/ir/ir_emitter.cpp
+++ b/src/frontend/ir/ir_emitter.cpp
@@ -1932,6 +1932,17 @@ U128 IREmitter::FPVectorRecipStepFused(size_t esize, const U128& a, const U128&
     return {};
 }
 
+U128 IREmitter::FPVectorRoundInt(size_t esize, const U128& operand, FP::RoundingMode rounding, bool exact) {
+    switch (esize) {
+    case 32:
+        return Inst<U128>(Opcode::FPVectorRoundInt32, operand, Imm8(static_cast<u8>(rounding)), Imm1(exact));
+    case 64:
+        return Inst<U128>(Opcode::FPVectorRoundInt64, operand, Imm8(static_cast<u8>(rounding)), Imm1(exact));
+    }
+    UNREACHABLE();
+    return {};
+}
+
 U128 IREmitter::FPVectorRSqrtEstimate(size_t esize, const U128& a) {
     switch (esize) {
     case 32:
diff --git a/src/frontend/ir/ir_emitter.h b/src/frontend/ir/ir_emitter.h
index 47c005ee..fa7a907e 100644
--- a/src/frontend/ir/ir_emitter.h
+++ b/src/frontend/ir/ir_emitter.h
@@ -320,6 +320,7 @@ public:
     U128 FPVectorPairedAddLower(size_t esize, const U128& a, const U128& b);
     U128 FPVectorRecipEstimate(size_t esize, const U128& a);
     U128 FPVectorRecipStepFused(size_t esize, const U128& a, const U128& b);
+    U128 FPVectorRoundInt(size_t esize, const U128& operand, FP::RoundingMode rounding, bool exact);
     U128 FPVectorRSqrtEstimate(size_t esize, const U128& a);
     U128 FPVectorRSqrtStepFused(size_t esize, const U128& a, const U128& b);
     U128 FPVectorS32ToSingle(const U128& a);
diff --git a/src/frontend/ir/opcodes.inc b/src/frontend/ir/opcodes.inc
index 5890433e..105da9dc 100644
--- a/src/frontend/ir/opcodes.inc
+++ b/src/frontend/ir/opcodes.inc
@@ -491,6 +491,8 @@ OPCODE(FPVectorRecipEstimate32,                 T::U128,        T::U128
 OPCODE(FPVectorRecipEstimate64,                 T::U128,        T::U128                                         )
 OPCODE(FPVectorRecipStepFused32,                T::U128,        T::U128,        T::U128                         )
 OPCODE(FPVectorRecipStepFused64,                T::U128,        T::U128,        T::U128                         )
+OPCODE(FPVectorRoundInt32,                      T::U128,        T::U128,        T::U8,          T::U1           )
+OPCODE(FPVectorRoundInt64,                      T::U128,        T::U128,        T::U8,          T::U1           )
 OPCODE(FPVectorRSqrtEstimate32,                 T::U128,        T::U128                                         )
 OPCODE(FPVectorRSqrtEstimate64,                 T::U128,        T::U128                                         )
 OPCODE(FPVectorRSqrtStepFused32,                T::U128,        T::U128,        T::U128                         )