// Copyright 2015, ARM Limited
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of ARM Limited nor the names of its contributors may be
// used to endorse or promote products derived from this software without
// specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "vixl/globals.h"
#include "vixl/a64/macro-assembler-a64.h"
#include "vixl/a64/instructions-a64.h"
using namespace vixl;
static const int kDefaultIterationCount = 100000;
// This program focuses on emitting branch instructions targeting a label bound
// very closely. Here the MacroAssembler is used. This exercises label binding
// and patching mechanisms, as well as the veneer resolving mechanisms for
// branches not requiring veneers.
int main(int argc, char* argv[]) {
int iterations = 0;
switch (argc) {
case 1: iterations = kDefaultIterationCount; break;
case 2: iterations = atoi(argv[1]); break;
default:
printf("Usage: %s [#iterations]\n", argv[0]);
exit(1);
}
const int buffer_size = 256 * KBytes;
const int instructions_per_iteration = 4;
const int max_buffer_iterations =
buffer_size / (instructions_per_iteration * kInstructionSize);
MacroAssembler masm(buffer_size);
#define __ masm.
for (int i = 0; i < iterations;) {
masm.Reset();
for (int j = 0; (j < max_buffer_iterations) && (i < iterations); ++j, ++i) {
Label target;
__ B(&target);
__ B(eq, &target);
__ Cbz(x2, &target);
__ Tbz(x3, 2, &target);
__ Bind(&target);
}
}
masm.FinalizeCode();
return 0;
}