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 kDefaultInstructionCount = 100000;
37
38 // This program focuses on emitting branch instructions.
39 //
40 // This code will emit a given number of branch immediate to the next
41 // instructions in a fixed size buffer, looping over the buffer if necessary.
42 // This code therefore focuses on Emit and label binding/patching.
main(int argc,char * argv[])43 int main(int argc, char* argv[]) {
44 int instructions = 0;
45
46 switch (argc) {
47 case 1:
48 instructions = kDefaultInstructionCount;
49 break;
50 case 2:
51 instructions = atoi(argv[1]);
52 break;
53 default:
54 printf("Usage: %s [#instructions]\n", argv[0]);
55 exit(1);
56 }
57
58 const int buffer_size = 256 * KBytes;
59 const int buffer_instruction_count = buffer_size / kInstructionSize;
60 timeval start;
61 gettimeofday(&start, NULL);
62 MacroAssembler masm(buffer_size);
63
64 #define __ masm.
65 // We emit a branch to the next instruction.
66
67 int rounds = instructions / buffer_instruction_count;
68 for (int i = 0; i < rounds; ++i) {
69 {
70 ExactAssemblyScope scope(&masm, buffer_size);
71 for (int j = 0; j < buffer_instruction_count; ++j) {
72 Label target;
73 __ b(&target);
74 __ bind(&target);
75 }
76 }
77 masm.Reset();
78 }
79
80 int remaining = instructions % buffer_instruction_count;
81 {
82 ExactAssemblyScope scope(&masm, remaining * kInstructionSize);
83 for (int i = 0; i < remaining; ++i) {
84 Label target;
85 __ b(&target);
86 __ bind(&target);
87 }
88 }
89
90 masm.FinalizeCode();
91 timeval end;
92 gettimeofday(&end, NULL);
93 double delta = (end.tv_sec - start.tv_sec) +
94 static_cast<double>(end.tv_usec - start.tv_usec) / 1000000;
95 printf("A64: time for %d instructions: %gs\n", instructions, delta);
96
97 return 0;
98 }
99