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// Copyright 2014, VIXL authors
// 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 "examples.h"
#define __ masm->
void GenerateCheckBounds(MacroAssembler* masm) {
// uint64_t check_bounds(uint64_t value, uint64_t low, uint64_t high)
// Argument locations:
// value -> x0
// low -> x1
// high -> x2
// First we compare 'value' with the 'low' bound. If x1 <= x0 the N flag will
// be cleared. This configuration can be checked with the 'pl' condition.
__ Cmp(x0, x1);
// Now we will compare 'value' and 'high' (x0 and x2) but only if the 'pl'
// condition is verified. If the condition is not verified, we will clear
// all the flags except the carry one (C flag).
__ Ccmp(x0, x2, CFlag, pl);
// We set x0 to 1 only if the 'ls' condition is satisfied.
// 'ls' performs the following test: !(C==1 && Z==0). If the previous
// comparison has been skipped we have C==1 and Z==0, so the 'ls' test
// will fail and x0 will be set to 0.
// Otherwise if the previous comparison occurred, x0 will be set to 1
// only if x0 is less than or equal to x2.
__ Cset(x0, ls);
__ Ret();
}
#ifndef TEST_EXAMPLES
#ifdef VIXL_INCLUDE_SIMULATOR
void run_function(Simulator* simulator,
Instruction* function,
uint64_t value,
uint64_t low,
uint64_t high) {
simulator->WriteXRegister(0, value);
simulator->WriteXRegister(1, low);
simulator->WriteXRegister(2, high);
simulator->RunFrom(function);
printf("%" PRIu64 " %s between %" PRIu64 " and %" PRIu64 "\n",
value,
simulator->ReadXRegister(0) ? "is" : "is not",
low,
high);
simulator->ResetState();
}
int main(void) {
MacroAssembler masm;
Decoder decoder;
Simulator simulator(&decoder);
// Generate the code for the example function.
Label check_bounds;
masm.Bind(&check_bounds);
GenerateCheckBounds(&masm);
masm.FinalizeCode();
// Run the example function.
Instruction* function = masm.GetLabelAddress<Instruction*>(&check_bounds);
run_function(&simulator, function, 546, 50, 1000);
run_function(&simulator, function, 62, 100, 200);
run_function(&simulator, function, 200, 100, 200);
return 0;
}
#else
// Without the simulator there is nothing to test.
int main(void) { return 0; }
#endif // VIXL_INCLUDE_SIMULATOR
#endif // TEST_EXAMPLES
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