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1 // Copyright 2015, VIXL authors
2 // All rights reserved.
3 //
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are met:
6 //
7 //   * Redistributions of source code must retain the above copyright notice,
8 //     this list of conditions and the following disclaimer.
9 //   * Redistributions in binary form must reproduce the above copyright notice,
10 //     this list of conditions and the following disclaimer in the documentation
11 //     and/or other materials provided with the distribution.
12 //   * Neither the name of ARM Limited nor the names of its contributors may be
13 //     used to endorse or promote products derived from this software without
14 //     specific prior written permission.
15 //
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND
17 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
20 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 
27 #include <sys/time.h>
28 #include "globals-vixl.h"
29 
30 #include "aarch64/instructions-aarch64.h"
31 #include "aarch64/macro-assembler-aarch64.h"
32 
33 using namespace vixl;
34 using namespace vixl::aarch64;
35 
36 static const int kDefaultIterationCount = 100000;
37 
38 // This program focuses on emitting branch instructions targeting a label bound
39 // very closely. Here the MacroAssembler is used. This exercises label binding
40 // and patching mechanisms, as well as the veneer resolving mechanisms for
41 // branches not requiring veneers.
main(int argc,char * argv[])42 int main(int argc, char* argv[]) {
43   int iterations = 0;
44 
45   switch (argc) {
46     case 1:
47       iterations = kDefaultIterationCount;
48       break;
49     case 2:
50       iterations = atoi(argv[1]);
51       break;
52     default:
53       printf("Usage: %s [#iterations]\n", argv[0]);
54       exit(1);
55   }
56 
57   const int buffer_size = 256 * KBytes;
58   const int instructions_per_iteration = 4;
59   const int max_buffer_iterations =
60       buffer_size / (instructions_per_iteration * kInstructionSize);
61 
62   timeval start;
63   gettimeofday(&start, NULL);
64   MacroAssembler masm(buffer_size);
65 
66 #define __ masm.
67 
68   for (int i = 0; i < iterations;) {
69     masm.Reset();
70     for (int j = 0; (j < max_buffer_iterations) && (i < iterations); ++j, ++i) {
71       Label target;
72       __ B(&target);
73       __ B(eq, &target);
74       __ Cbz(x2, &target);
75       __ Tbz(x3, 2, &target);
76       __ Bind(&target);
77     }
78   }
79 
80   masm.FinalizeCode();
81 
82   timeval end;
83   gettimeofday(&end, NULL);
84   double delta = (end.tv_sec - start.tv_sec) +
85                  static_cast<double>(end.tv_usec - start.tv_usec) / 1000000;
86   printf("A64: time for %d iterations: %gs\n", iterations, delta);
87 
88   return 0;
89 }
90