// 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_AARCH64 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_AARCH64 #endif // TEST_EXAMPLES