From ef906dbbfa47a80d5b90df84ca275f69f2772676 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Mon, 5 Feb 2018 12:25:04 +0000
Subject: [PATCH] A64: Implement FCCMP

---
 src/CMakeLists.txt                            |  1 +
 src/frontend/A64/decoder/a64.inc              |  2 +-
 .../floating_point_conditional_compare.cpp    | 41 +++++++++++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 src/frontend/A64/translate/impl/floating_point_conditional_compare.cpp

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 5b4949d8..e8d2fdf0 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -77,6 +77,7 @@ add_library(dynarmic
     frontend/A64/translate/impl/exception_generating.cpp
     frontend/A64/translate/impl/floating_point_compare.cpp
     frontend/A64/translate/impl/floating_point_conversion_integer.cpp
+    frontend/A64/translate/impl/floating_point_conditional_compare.cpp
     frontend/A64/translate/impl/floating_point_conditional_select.cpp
     frontend/A64/translate/impl/floating_point_data_processing_one_register.cpp
     frontend/A64/translate/impl/floating_point_data_processing_two_register.cpp
diff --git a/src/frontend/A64/decoder/a64.inc b/src/frontend/A64/decoder/a64.inc
index f7646460..c3b76900 100644
--- a/src/frontend/A64/decoder/a64.inc
+++ b/src/frontend/A64/decoder/a64.inc
@@ -912,7 +912,7 @@ INST(FCMPE_float,            "FCMPE",                                     "00011
 INST(FMOV_float_imm,         "FMOV (scalar, immediate)",                  "00011110yy1iiiiiiii10000000ddddd")
 
 // Data Processing - FP and SIMD - Floating point conditional compare
-//INST(FCCMP_float,            "FCCMP",                                     "00011110yy1mmmmmcccc01nnnnn0ffff")
+INST(FCCMP_float,            "FCCMP",                                     "00011110yy1mmmmmcccc01nnnnn0ffff")
 //INST(FCCMPE_float,           "FCCMPE",                                    "00011110yy1mmmmmcccc01nnnnn1ffff")
 
 // Data Processing - FP and SIMD - Floating point data processing two register
diff --git a/src/frontend/A64/translate/impl/floating_point_conditional_compare.cpp b/src/frontend/A64/translate/impl/floating_point_conditional_compare.cpp
new file mode 100644
index 00000000..dbe710ed
--- /dev/null
+++ b/src/frontend/A64/translate/impl/floating_point_conditional_compare.cpp
@@ -0,0 +1,41 @@
+/* This file is part of the dynarmic project.
+ * Copyright (c) 2018 MerryMage
+ * This software may be used and distributed according to the terms of the GNU
+ * General Public License version 2 or any later version.
+ */
+
+#include <boost/optional.hpp>
+
+#include "frontend/A64/translate/impl/impl.h"
+
+namespace Dynarmic::A64 {
+
+static boost::optional<size_t> GetDataSize(Imm<2> type) {
+    switch (type.ZeroExtend()) {
+    case 0b00:
+        return 32;
+    case 0b01:
+        return 64;
+    case 0b11:
+        return 16;
+    }
+    return boost::none;
+}
+
+bool TranslatorVisitor::FCCMP_float(Imm<2> type, Vec Vm, Cond cond, Vec Vn, Imm<4> nzcv) {
+    const auto datasize = GetDataSize(type);
+    if (!datasize || *datasize == 16) {
+        return UnallocatedEncoding();
+    }
+    const u32 flags = nzcv.ZeroExtend<u32>() << 28;
+
+    const IR::U32U64 operand1 = V_scalar(*datasize, Vn);
+    const IR::U32U64 operand2 = V_scalar(*datasize, Vm);
+
+    const IR::NZCV then_flags = ir.FPCompare(operand1, operand2, false, true);
+    const IR::NZCV else_flags = ir.NZCVFromPackedFlags(ir.Imm32(flags));
+    ir.SetNZCV(ir.ConditionalSelect(cond, then_flags, else_flags));
+    return true;
+}
+
+} // namespace Dynarmic::A64