1/*
2 * Copyright (c) 2016 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Nathanael Premillieu
38 */
39
40#ifndef __CPU_INST_RES_HH__
41#define __CPU_INST_RES_HH__
42
43#include <type_traits>
44
45#include "arch/generic/types.hh"
46#include "arch/generic/vec_reg.hh"
47
48class InstResult {
49 using VecRegContainer = TheISA::VecRegContainer;
50 using VecElem = TheISA::VecElem;
51 public:
52 union MultiResult {
53 uint64_t integer;
54 double dbl;
55 VecRegContainer vector;
56 VecElem vecElem;
57 MultiResult() {}
58 };
59
60 enum class ResultType {
61 Scalar,
62 VecElem,
63 VecReg,
64 NumResultTypes,
65 Invalid
66 };
67
68 private:
69 MultiResult result;
70 ResultType type;
71
72 public:
73 /** Default constructor creates an invalid result. */
74 InstResult() : type(ResultType::Invalid) { }
75 /** Scalar result from scalar. */
76 template<typename T>
77 explicit InstResult(T i, const ResultType& t) : type(t) {
78 static_assert(std::is_integral<T>::value ^
79 std::is_floating_point<T>::value,
80 "Parameter type is neither integral nor fp, or it is both");
81 if (std::is_integral<T>::value) {
82 result.integer = i;
83 } else if (std::is_floating_point<T>::value) {
84 result.dbl = i;
85 }
86 }
87 /** Vector result. */
88 explicit InstResult(const VecRegContainer& v, const ResultType& t)
89 : type(t) { result.vector = v; }
90
91 InstResult& operator=(const InstResult& that) {
92 type = that.type;
93 switch (type) {
94 /* Given that misc regs are not written to, there may be invalids in
95 * the result stack. */
96 case ResultType::Invalid:
97 break;
98 case ResultType::Scalar:
99 result.integer = that.result.integer;
100 break;
101 case ResultType::VecElem:
102 result.vecElem = that.result.vecElem;
103 break;
104 case ResultType::VecReg:
105 result.vector = that.result.vector;
106 break;
107 default:
108 panic("Assigning result from unknown result type");
109 break;
110 }
111 return *this;
112 }
113 /**
114 * Result comparison
115 * Two invalid results always differ.
116 */
117 bool operator==(const InstResult& that) const {
118 if (this->type != that.type)
119 return false;
120 switch (type) {
121 case ResultType::Scalar:
122 return result.integer == that.result.integer;
123 case ResultType::VecElem:
124 return result.vecElem == that.result.vecElem;
125 case ResultType::VecReg:
126 return result.vector == that.result.vector;
127 case ResultType::Invalid:
128 return false;
129 default:
130 panic("Unknown type of result: %d\n", (int)type);
131 }
132 }
133
134 bool operator!=(const InstResult& that) const {
135 return !operator==(that);
136 }
137
138 /** Checks */
139 /** @{ */
140 /** Is this a scalar result?. */
141 bool isScalar() const { return type == ResultType::Scalar; }
142 /** Is this a vector result?. */
143 bool isVector() const { return type == ResultType::VecReg; }
144 /** Is this a vector element result?. */
145 bool isVecElem() const { return type == ResultType::VecElem; }
146 /** Is this a valid result?. */
147 bool isValid() const { return type != ResultType::Invalid; }
148 /** @} */
149
150 /** Explicit cast-like operations. */
151 /** @{ */
152 const uint64_t&
153 asInteger() const
154 {
155 assert(isScalar());
156 return result.integer;
157 }
158
159 /** Cast to integer without checking type.
160 * This is required to have the o3 cpu checker happy, as it
161 * compares results as integers without being fully aware of
162 * their nature. */
163 const uint64_t&
164 asIntegerNoAssert() const
165 {
166 return result.integer;
167 }
168 const VecRegContainer&
169 asVector() const
170 {
171 panic_if(!isVector(), "Converting scalar (or invalid) to vector!!");
172 return result.vector;
173 }
174 const VecElem&
175 asVectorElem() const
176 {
177 panic_if(!isVecElem(), "Converting scalar (or invalid) to vector!!");
178 return result.vecElem;
179 }
180 /** @} */
181};
182
183#endif // __CPU_INST_RES_HH__