xref: /llvm-project/llvm/unittests/Support/LEB128Test.cpp (revision 2946cd701067404b99c39fb29dc9c74bd7193eb3)
1 //===- llvm/unittest/Support/LEB128Test.cpp - LEB128 function tests -------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/Support/LEB128.h"
10 #include "llvm/Support/DataTypes.h"
11 #include "llvm/Support/raw_ostream.h"
12 #include "gtest/gtest.h"
13 #include <string>
14 using namespace llvm;
15 
16 namespace {
17 
18 TEST(LEB128Test, EncodeSLEB128) {
19 #define EXPECT_SLEB128_EQ(EXPECTED, VALUE, PAD) \
20   do { \
21     std::string Expected(EXPECTED, sizeof(EXPECTED) - 1); \
22     \
23     /* encodeSLEB128(uint64_t, raw_ostream &, unsigned) */ \
24     std::string Actual1; \
25     raw_string_ostream Stream(Actual1); \
26     encodeSLEB128(VALUE, Stream, PAD); \
27     Stream.flush(); \
28     EXPECT_EQ(Expected, Actual1); \
29     \
30     /* encodeSLEB128(uint64_t, uint8_t *, unsigned) */ \
31     uint8_t Buffer[32]; \
32     unsigned Size = encodeSLEB128(VALUE, Buffer, PAD); \
33     std::string Actual2(reinterpret_cast<const char *>(Buffer), Size); \
34     EXPECT_EQ(Expected, Actual2); \
35   } while (0)
36 
37   // Encode SLEB128
38   EXPECT_SLEB128_EQ("\x00", 0, 0);
39   EXPECT_SLEB128_EQ("\x01", 1, 0);
40   EXPECT_SLEB128_EQ("\x7f", -1, 0);
41   EXPECT_SLEB128_EQ("\x3f", 63, 0);
42   EXPECT_SLEB128_EQ("\x41", -63, 0);
43   EXPECT_SLEB128_EQ("\x40", -64, 0);
44   EXPECT_SLEB128_EQ("\xbf\x7f", -65, 0);
45   EXPECT_SLEB128_EQ("\xc0\x00", 64, 0);
46 
47   // Encode SLEB128 with some extra padding bytes
48   EXPECT_SLEB128_EQ("\x80\x00", 0, 2);
49   EXPECT_SLEB128_EQ("\x80\x80\x00", 0, 3);
50   EXPECT_SLEB128_EQ("\xff\x80\x00", 0x7f, 3);
51   EXPECT_SLEB128_EQ("\xff\x80\x80\x00", 0x7f, 4);
52   EXPECT_SLEB128_EQ("\x80\x81\x00", 0x80, 3);
53   EXPECT_SLEB128_EQ("\x80\x81\x80\x00", 0x80, 4);
54   EXPECT_SLEB128_EQ("\xc0\x7f", -0x40, 2);
55 
56   EXPECT_SLEB128_EQ("\xc0\xff\x7f", -0x40, 3);
57   EXPECT_SLEB128_EQ("\x80\xff\x7f", -0x80, 3);
58   EXPECT_SLEB128_EQ("\x80\xff\xff\x7f", -0x80, 4);
59 
60 #undef EXPECT_SLEB128_EQ
61 }
62 
63 TEST(LEB128Test, EncodeULEB128) {
64 #define EXPECT_ULEB128_EQ(EXPECTED, VALUE, PAD) \
65   do { \
66     std::string Expected(EXPECTED, sizeof(EXPECTED) - 1); \
67     \
68     /* encodeULEB128(uint64_t, raw_ostream &, unsigned) */ \
69     std::string Actual1; \
70     raw_string_ostream Stream(Actual1); \
71     encodeULEB128(VALUE, Stream, PAD); \
72     Stream.flush(); \
73     EXPECT_EQ(Expected, Actual1); \
74     \
75     /* encodeULEB128(uint64_t, uint8_t *, unsigned) */ \
76     uint8_t Buffer[32]; \
77     unsigned Size = encodeULEB128(VALUE, Buffer, PAD); \
78     std::string Actual2(reinterpret_cast<const char *>(Buffer), Size); \
79     EXPECT_EQ(Expected, Actual2); \
80   } while (0)
81 
82   // Encode ULEB128
83   EXPECT_ULEB128_EQ("\x00", 0, 0);
84   EXPECT_ULEB128_EQ("\x01", 1, 0);
85   EXPECT_ULEB128_EQ("\x3f", 63, 0);
86   EXPECT_ULEB128_EQ("\x40", 64, 0);
87   EXPECT_ULEB128_EQ("\x7f", 0x7f, 0);
88   EXPECT_ULEB128_EQ("\x80\x01", 0x80, 0);
89   EXPECT_ULEB128_EQ("\x81\x01", 0x81, 0);
90   EXPECT_ULEB128_EQ("\x90\x01", 0x90, 0);
91   EXPECT_ULEB128_EQ("\xff\x01", 0xff, 0);
92   EXPECT_ULEB128_EQ("\x80\x02", 0x100, 0);
93   EXPECT_ULEB128_EQ("\x81\x02", 0x101, 0);
94 
95   // Encode ULEB128 with some extra padding bytes
96   EXPECT_ULEB128_EQ("\x80\x00", 0, 2);
97   EXPECT_ULEB128_EQ("\x80\x80\x00", 0, 3);
98   EXPECT_ULEB128_EQ("\xff\x00", 0x7f, 2);
99   EXPECT_ULEB128_EQ("\xff\x80\x00", 0x7f, 3);
100   EXPECT_ULEB128_EQ("\x80\x81\x00", 0x80, 3);
101   EXPECT_ULEB128_EQ("\x80\x81\x80\x00", 0x80, 4);
102 
103 #undef EXPECT_ULEB128_EQ
104 }
105 
106 TEST(LEB128Test, DecodeULEB128) {
107 #define EXPECT_DECODE_ULEB128_EQ(EXPECTED, VALUE) \
108   do { \
109     unsigned ActualSize = 0; \
110     uint64_t Actual = decodeULEB128(reinterpret_cast<const uint8_t *>(VALUE), \
111                                     &ActualSize); \
112     EXPECT_EQ(sizeof(VALUE) - 1, ActualSize); \
113     EXPECT_EQ(EXPECTED, Actual); \
114   } while (0)
115 
116   // Decode ULEB128
117   EXPECT_DECODE_ULEB128_EQ(0u, "\x00");
118   EXPECT_DECODE_ULEB128_EQ(1u, "\x01");
119   EXPECT_DECODE_ULEB128_EQ(63u, "\x3f");
120   EXPECT_DECODE_ULEB128_EQ(64u, "\x40");
121   EXPECT_DECODE_ULEB128_EQ(0x7fu, "\x7f");
122   EXPECT_DECODE_ULEB128_EQ(0x80u, "\x80\x01");
123   EXPECT_DECODE_ULEB128_EQ(0x81u, "\x81\x01");
124   EXPECT_DECODE_ULEB128_EQ(0x90u, "\x90\x01");
125   EXPECT_DECODE_ULEB128_EQ(0xffu, "\xff\x01");
126   EXPECT_DECODE_ULEB128_EQ(0x100u, "\x80\x02");
127   EXPECT_DECODE_ULEB128_EQ(0x101u, "\x81\x02");
128   EXPECT_DECODE_ULEB128_EQ(4294975616ULL, "\x80\xc1\x80\x80\x10");
129 
130   // Decode ULEB128 with extra padding bytes
131   EXPECT_DECODE_ULEB128_EQ(0u, "\x80\x00");
132   EXPECT_DECODE_ULEB128_EQ(0u, "\x80\x80\x00");
133   EXPECT_DECODE_ULEB128_EQ(0x7fu, "\xff\x00");
134   EXPECT_DECODE_ULEB128_EQ(0x7fu, "\xff\x80\x00");
135   EXPECT_DECODE_ULEB128_EQ(0x80u, "\x80\x81\x00");
136   EXPECT_DECODE_ULEB128_EQ(0x80u, "\x80\x81\x80\x00");
137 
138 #undef EXPECT_DECODE_ULEB128_EQ
139 }
140 
141 TEST(LEB128Test, DecodeSLEB128) {
142 #define EXPECT_DECODE_SLEB128_EQ(EXPECTED, VALUE) \
143   do { \
144     unsigned ActualSize = 0; \
145     int64_t Actual = decodeSLEB128(reinterpret_cast<const uint8_t *>(VALUE), \
146                                     &ActualSize); \
147     EXPECT_EQ(sizeof(VALUE) - 1, ActualSize); \
148     EXPECT_EQ(EXPECTED, Actual); \
149   } while (0)
150 
151   // Decode SLEB128
152   EXPECT_DECODE_SLEB128_EQ(0L, "\x00");
153   EXPECT_DECODE_SLEB128_EQ(1L, "\x01");
154   EXPECT_DECODE_SLEB128_EQ(63L, "\x3f");
155   EXPECT_DECODE_SLEB128_EQ(-64L, "\x40");
156   EXPECT_DECODE_SLEB128_EQ(-63L, "\x41");
157   EXPECT_DECODE_SLEB128_EQ(-1L, "\x7f");
158   EXPECT_DECODE_SLEB128_EQ(128L, "\x80\x01");
159   EXPECT_DECODE_SLEB128_EQ(129L, "\x81\x01");
160   EXPECT_DECODE_SLEB128_EQ(-129L, "\xff\x7e");
161   EXPECT_DECODE_SLEB128_EQ(-128L, "\x80\x7f");
162   EXPECT_DECODE_SLEB128_EQ(-127L, "\x81\x7f");
163   EXPECT_DECODE_SLEB128_EQ(64L, "\xc0\x00");
164   EXPECT_DECODE_SLEB128_EQ(-12345L, "\xc7\x9f\x7f");
165 
166   // Decode unnormalized SLEB128 with extra padding bytes.
167   EXPECT_DECODE_SLEB128_EQ(0L, "\x80\x00");
168   EXPECT_DECODE_SLEB128_EQ(0L, "\x80\x80\x00");
169   EXPECT_DECODE_SLEB128_EQ(0x7fL, "\xff\x00");
170   EXPECT_DECODE_SLEB128_EQ(0x7fL, "\xff\x80\x00");
171   EXPECT_DECODE_SLEB128_EQ(0x80L, "\x80\x81\x00");
172   EXPECT_DECODE_SLEB128_EQ(0x80L, "\x80\x81\x80\x00");
173 
174 #undef EXPECT_DECODE_SLEB128_EQ
175 }
176 
177 TEST(LEB128Test, SLEB128Size) {
178   // Positive Value Testing Plan:
179   // (1) 128 ^ n - 1 ........ need (n+1) bytes
180   // (2) 128 ^ n ............ need (n+1) bytes
181   // (3) 128 ^ n * 63 ....... need (n+1) bytes
182   // (4) 128 ^ n * 64 - 1 ... need (n+1) bytes
183   // (5) 128 ^ n * 64 ....... need (n+2) bytes
184 
185   EXPECT_EQ(1u, getSLEB128Size(0x0LL));
186   EXPECT_EQ(1u, getSLEB128Size(0x1LL));
187   EXPECT_EQ(1u, getSLEB128Size(0x3fLL));
188   EXPECT_EQ(1u, getSLEB128Size(0x3fLL));
189   EXPECT_EQ(2u, getSLEB128Size(0x40LL));
190 
191   EXPECT_EQ(2u, getSLEB128Size(0x7fLL));
192   EXPECT_EQ(2u, getSLEB128Size(0x80LL));
193   EXPECT_EQ(2u, getSLEB128Size(0x1f80LL));
194   EXPECT_EQ(2u, getSLEB128Size(0x1fffLL));
195   EXPECT_EQ(3u, getSLEB128Size(0x2000LL));
196 
197   EXPECT_EQ(3u, getSLEB128Size(0x3fffLL));
198   EXPECT_EQ(3u, getSLEB128Size(0x4000LL));
199   EXPECT_EQ(3u, getSLEB128Size(0xfc000LL));
200   EXPECT_EQ(3u, getSLEB128Size(0xfffffLL));
201   EXPECT_EQ(4u, getSLEB128Size(0x100000LL));
202 
203   EXPECT_EQ(4u, getSLEB128Size(0x1fffffLL));
204   EXPECT_EQ(4u, getSLEB128Size(0x200000LL));
205   EXPECT_EQ(4u, getSLEB128Size(0x7e00000LL));
206   EXPECT_EQ(4u, getSLEB128Size(0x7ffffffLL));
207   EXPECT_EQ(5u, getSLEB128Size(0x8000000LL));
208 
209   EXPECT_EQ(5u, getSLEB128Size(0xfffffffLL));
210   EXPECT_EQ(5u, getSLEB128Size(0x10000000LL));
211   EXPECT_EQ(5u, getSLEB128Size(0x3f0000000LL));
212   EXPECT_EQ(5u, getSLEB128Size(0x3ffffffffLL));
213   EXPECT_EQ(6u, getSLEB128Size(0x400000000LL));
214 
215   EXPECT_EQ(6u, getSLEB128Size(0x7ffffffffLL));
216   EXPECT_EQ(6u, getSLEB128Size(0x800000000LL));
217   EXPECT_EQ(6u, getSLEB128Size(0x1f800000000LL));
218   EXPECT_EQ(6u, getSLEB128Size(0x1ffffffffffLL));
219   EXPECT_EQ(7u, getSLEB128Size(0x20000000000LL));
220 
221   EXPECT_EQ(7u, getSLEB128Size(0x3ffffffffffLL));
222   EXPECT_EQ(7u, getSLEB128Size(0x40000000000LL));
223   EXPECT_EQ(7u, getSLEB128Size(0xfc0000000000LL));
224   EXPECT_EQ(7u, getSLEB128Size(0xffffffffffffLL));
225   EXPECT_EQ(8u, getSLEB128Size(0x1000000000000LL));
226 
227   EXPECT_EQ(8u, getSLEB128Size(0x1ffffffffffffLL));
228   EXPECT_EQ(8u, getSLEB128Size(0x2000000000000LL));
229   EXPECT_EQ(8u, getSLEB128Size(0x7e000000000000LL));
230   EXPECT_EQ(8u, getSLEB128Size(0x7fffffffffffffLL));
231   EXPECT_EQ(9u, getSLEB128Size(0x80000000000000LL));
232 
233   EXPECT_EQ(9u, getSLEB128Size(0xffffffffffffffLL));
234   EXPECT_EQ(9u, getSLEB128Size(0x100000000000000LL));
235   EXPECT_EQ(9u, getSLEB128Size(0x3f00000000000000LL));
236   EXPECT_EQ(9u, getSLEB128Size(0x3fffffffffffffffLL));
237   EXPECT_EQ(10u, getSLEB128Size(0x4000000000000000LL));
238 
239   EXPECT_EQ(10u, getSLEB128Size(0x7fffffffffffffffLL));
240   EXPECT_EQ(10u, getSLEB128Size(INT64_MAX));
241 
242   // Negative Value Testing Plan:
243   // (1) - 128 ^ n - 1 ........ need (n+1) bytes
244   // (2) - 128 ^ n ............ need (n+1) bytes
245   // (3) - 128 ^ n * 63 ....... need (n+1) bytes
246   // (4) - 128 ^ n * 64 ....... need (n+1) bytes (different from positive one)
247   // (5) - 128 ^ n * 65 - 1 ... need (n+2) bytes (if n > 0)
248   // (6) - 128 ^ n * 65 ....... need (n+2) bytes
249 
250   EXPECT_EQ(1u, getSLEB128Size(0x0LL));
251   EXPECT_EQ(1u, getSLEB128Size(-0x1LL));
252   EXPECT_EQ(1u, getSLEB128Size(-0x3fLL));
253   EXPECT_EQ(1u, getSLEB128Size(-0x40LL));
254   EXPECT_EQ(1u, getSLEB128Size(-0x40LL)); // special case
255   EXPECT_EQ(2u, getSLEB128Size(-0x41LL));
256 
257   EXPECT_EQ(2u, getSLEB128Size(-0x7fLL));
258   EXPECT_EQ(2u, getSLEB128Size(-0x80LL));
259   EXPECT_EQ(2u, getSLEB128Size(-0x1f80LL));
260   EXPECT_EQ(2u, getSLEB128Size(-0x2000LL));
261   EXPECT_EQ(3u, getSLEB128Size(-0x207fLL));
262   EXPECT_EQ(3u, getSLEB128Size(-0x2080LL));
263 
264   EXPECT_EQ(3u, getSLEB128Size(-0x3fffLL));
265   EXPECT_EQ(3u, getSLEB128Size(-0x4000LL));
266   EXPECT_EQ(3u, getSLEB128Size(-0xfc000LL));
267   EXPECT_EQ(3u, getSLEB128Size(-0x100000LL));
268   EXPECT_EQ(4u, getSLEB128Size(-0x103fffLL));
269   EXPECT_EQ(4u, getSLEB128Size(-0x104000LL));
270 
271   EXPECT_EQ(4u, getSLEB128Size(-0x1fffffLL));
272   EXPECT_EQ(4u, getSLEB128Size(-0x200000LL));
273   EXPECT_EQ(4u, getSLEB128Size(-0x7e00000LL));
274   EXPECT_EQ(4u, getSLEB128Size(-0x8000000LL));
275   EXPECT_EQ(5u, getSLEB128Size(-0x81fffffLL));
276   EXPECT_EQ(5u, getSLEB128Size(-0x8200000LL));
277 
278   EXPECT_EQ(5u, getSLEB128Size(-0xfffffffLL));
279   EXPECT_EQ(5u, getSLEB128Size(-0x10000000LL));
280   EXPECT_EQ(5u, getSLEB128Size(-0x3f0000000LL));
281   EXPECT_EQ(5u, getSLEB128Size(-0x400000000LL));
282   EXPECT_EQ(6u, getSLEB128Size(-0x40fffffffLL));
283   EXPECT_EQ(6u, getSLEB128Size(-0x410000000LL));
284 
285   EXPECT_EQ(6u, getSLEB128Size(-0x7ffffffffLL));
286   EXPECT_EQ(6u, getSLEB128Size(-0x800000000LL));
287   EXPECT_EQ(6u, getSLEB128Size(-0x1f800000000LL));
288   EXPECT_EQ(6u, getSLEB128Size(-0x20000000000LL));
289   EXPECT_EQ(7u, getSLEB128Size(-0x207ffffffffLL));
290   EXPECT_EQ(7u, getSLEB128Size(-0x20800000000LL));
291 
292   EXPECT_EQ(7u, getSLEB128Size(-0x3ffffffffffLL));
293   EXPECT_EQ(7u, getSLEB128Size(-0x40000000000LL));
294   EXPECT_EQ(7u, getSLEB128Size(-0xfc0000000000LL));
295   EXPECT_EQ(7u, getSLEB128Size(-0x1000000000000LL));
296   EXPECT_EQ(8u, getSLEB128Size(-0x103ffffffffffLL));
297   EXPECT_EQ(8u, getSLEB128Size(-0x1040000000000LL));
298 
299   EXPECT_EQ(8u, getSLEB128Size(-0x1ffffffffffffLL));
300   EXPECT_EQ(8u, getSLEB128Size(-0x2000000000000LL));
301   EXPECT_EQ(8u, getSLEB128Size(-0x7e000000000000LL));
302   EXPECT_EQ(8u, getSLEB128Size(-0x80000000000000LL));
303   EXPECT_EQ(9u, getSLEB128Size(-0x81ffffffffffffLL));
304   EXPECT_EQ(9u, getSLEB128Size(-0x82000000000000LL));
305 
306   EXPECT_EQ(9u, getSLEB128Size(-0xffffffffffffffLL));
307   EXPECT_EQ(9u, getSLEB128Size(-0x100000000000000LL));
308   EXPECT_EQ(9u, getSLEB128Size(-0x3f00000000000000LL));
309   EXPECT_EQ(9u, getSLEB128Size(-0x4000000000000000LL));
310   EXPECT_EQ(10u, getSLEB128Size(-0x40ffffffffffffffLL));
311   EXPECT_EQ(10u, getSLEB128Size(-0x4100000000000000LL));
312 
313   EXPECT_EQ(10u, getSLEB128Size(-0x7fffffffffffffffLL));
314   EXPECT_EQ(10u, getSLEB128Size(-0x8000000000000000LL));
315   EXPECT_EQ(10u, getSLEB128Size(INT64_MIN));
316 }
317 
318 TEST(LEB128Test, ULEB128Size) {
319   // Testing Plan:
320   // (1) 128 ^ n ............ need (n+1) bytes
321   // (2) 128 ^ n * 64 ....... need (n+1) bytes
322   // (3) 128 ^ (n+1) - 1 .... need (n+1) bytes
323 
324   EXPECT_EQ(1u, getULEB128Size(0)); // special case
325 
326   EXPECT_EQ(1u, getULEB128Size(0x1ULL));
327   EXPECT_EQ(1u, getULEB128Size(0x40ULL));
328   EXPECT_EQ(1u, getULEB128Size(0x7fULL));
329 
330   EXPECT_EQ(2u, getULEB128Size(0x80ULL));
331   EXPECT_EQ(2u, getULEB128Size(0x2000ULL));
332   EXPECT_EQ(2u, getULEB128Size(0x3fffULL));
333 
334   EXPECT_EQ(3u, getULEB128Size(0x4000ULL));
335   EXPECT_EQ(3u, getULEB128Size(0x100000ULL));
336   EXPECT_EQ(3u, getULEB128Size(0x1fffffULL));
337 
338   EXPECT_EQ(4u, getULEB128Size(0x200000ULL));
339   EXPECT_EQ(4u, getULEB128Size(0x8000000ULL));
340   EXPECT_EQ(4u, getULEB128Size(0xfffffffULL));
341 
342   EXPECT_EQ(5u, getULEB128Size(0x10000000ULL));
343   EXPECT_EQ(5u, getULEB128Size(0x400000000ULL));
344   EXPECT_EQ(5u, getULEB128Size(0x7ffffffffULL));
345 
346   EXPECT_EQ(6u, getULEB128Size(0x800000000ULL));
347   EXPECT_EQ(6u, getULEB128Size(0x20000000000ULL));
348   EXPECT_EQ(6u, getULEB128Size(0x3ffffffffffULL));
349 
350   EXPECT_EQ(7u, getULEB128Size(0x40000000000ULL));
351   EXPECT_EQ(7u, getULEB128Size(0x1000000000000ULL));
352   EXPECT_EQ(7u, getULEB128Size(0x1ffffffffffffULL));
353 
354   EXPECT_EQ(8u, getULEB128Size(0x2000000000000ULL));
355   EXPECT_EQ(8u, getULEB128Size(0x80000000000000ULL));
356   EXPECT_EQ(8u, getULEB128Size(0xffffffffffffffULL));
357 
358   EXPECT_EQ(9u, getULEB128Size(0x100000000000000ULL));
359   EXPECT_EQ(9u, getULEB128Size(0x4000000000000000ULL));
360   EXPECT_EQ(9u, getULEB128Size(0x7fffffffffffffffULL));
361 
362   EXPECT_EQ(10u, getULEB128Size(0x8000000000000000ULL));
363 
364   EXPECT_EQ(10u, getULEB128Size(UINT64_MAX));
365 }
366 
367 }  // anonymous namespace
368