vixl/examples/neon-matrix-multiply.cc
armvixl 0f35e36b7f VIXL Release 1.13
Refer to the README.md and LICENCE files for details.

Change-Id: I922914f4e7da7cb939a8054cded11feb9ea51a86
2016-05-13 15:06:20 +01:00

205 lines
6.8 KiB
C++

// 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 "examples.h"
#define BUF_SIZE (4096)
#define __ masm->
// A vector by scalar multiply helper routine to generate code for
// the multiplication of each column of the resulting 4x4 matrix.
// This function provides a template for the following pattern:
//
// __ Fmul(v<v_out>.V4S(), v4.V4S(), v<s_column>.S(), 0);
// __ Fmla(v<v_out>.V4S(), v5.V4S(), v<s_column>.S(), 1);
// __ Fmla(v<v_out>.V4S(), v6.V4S(), v<s_column>.S(), 2);
// __ Fmla(v<v_out>.V4S(), v7.V4S(), v<s_column>.S(), 3);
//
// v<v_out> corresponds to a column of the output matrix (v0, v1, v2 or v3).
// v<s_column> corresponds to a column of the 2nd input (v16, v17, v18 or v19).
//
static void GenerateMultiplyColumn(MacroAssembler* masm,
unsigned out_column,
unsigned in_column) {
// 'v_out' splits a Q register into 4 lanes of 32 bits each.
VRegister v_out = VRegister(out_column, kQRegSize, 4);
// 'v_in' refers to a single 32 bit 'S' lane.
VRegister v_in = VRegister(in_column, kSRegSize);
__ Fmul(v_out, v4.V4S(), v_in, 0); // e.g. (v0.V4S(), v4.V4S(), v8.S(), 0).
__ Fmla(v_out, v5.V4S(), v_in, 1);
__ Fmla(v_out, v6.V4S(), v_in, 2);
__ Fmla(v_out, v7.V4S(), v_in, 3);
}
void GenerateNEONMatrixMultiply(MacroAssembler* masm) {
// Argument location:
// dst -> x0
// mat1 -> x1
// mat2 -> x2
Label end;
__ And(x3, x0, x1);
__ And(x3, x3, x2);
__ Cbz(x3, &end); // Nothing to do if an input is null.
// Load the first matrix into v4, v5, v6 and v7.
__ Ld1(v4.V4S(), v5.V4S(), v6.V4S(), v7.V4S(), MemOperand(x1));
// Load the first matrix into v16, v17, v18 and v19.
__ Ld1(v16.V4S(), v17.V4S(), v18.V4S(), v19.V4S(), MemOperand(x2));
// Initialise vectors of the output matrix with zeros.
// This is only for the purposes of showing how this can be achived
// but technically this is not required because we overwrite all lanes
// of the output vectors.
__ Movi(v0.V16B(), 0);
__ Movi(v1.V16B(), 0);
__ Movi(v2.V16B(), 0);
__ Movi(v3.V16B(), 0);
GenerateMultiplyColumn(masm, 0, 16);
GenerateMultiplyColumn(masm, 1, 17);
GenerateMultiplyColumn(masm, 2, 18);
GenerateMultiplyColumn(masm, 3, 19);
// Store the resulting matrix from v0, v1, v2 and v3.
__ St1(v0.V4S(), v1.V4S(), v2.V4S(), v3.V4S(), MemOperand(x0));
__ Bind(&end);
__ Ret();
}
#ifndef TEST_EXAMPLES
#ifdef VIXL_INCLUDE_SIMULATOR
int main(void) {
// Create and initialize the assembler and the simulator.
byte assm_buf[BUF_SIZE];
MacroAssembler masm(assm_buf, BUF_SIZE);
Decoder decoder;
Simulator simulator(&decoder);
// Generate the code for the example function.
Label neon_matrix_multiply;
masm.Bind(&neon_matrix_multiply);
GenerateNEONMatrixMultiply(&masm);
masm.FinalizeCode();
// Define the required variables and run the example function.
const int kRowSize = 4;
const int kColSize = 4;
const int kLength = kRowSize * kColSize;
float mat1[kLength], mat2[kLength], output[kLength];
// Initialise the output matrix to the zero matrix.
memset(output, 0, sizeof(output[0]) * kLength);
// Fill the two input matrices with some 32 bit floating point values.
// Array initialisation using curly brackets is also possible like so:
// float mat1[kLength] = { 1.0f, 52.03f, 4.43f, ... };
// However, the following way better shows the "column-major" arrangement.
mat1[0] = 1.0f;
mat1[4] = 2.0f;
mat1[8] = 3.0f;
mat1[12] = 4.0f;
mat1[1] = 52.03f;
mat1[5] = 12.24f;
mat1[9] = 53.56f;
mat1[13] = 22.22f;
mat1[2] = 4.43f;
mat1[6] = 5.00f;
mat1[10] = 7.00f;
mat1[14] = 3.11f;
mat1[3] = 43.47f;
mat1[7] = 10.97f;
mat1[11] = 37.78f;
mat1[15] = 90.91f;
mat2[0] = 1.0f;
mat2[4] = 11.24f;
mat2[8] = 21.00f;
mat2[12] = 21.31f;
mat2[1] = 2.0f;
mat2[5] = 2.24f;
mat2[9] = 8.56f;
mat2[13] = 52.03f;
mat2[2] = 3.0f;
mat2[6] = 51.00f;
mat2[10] = 21.00f;
mat2[14] = 33.11f;
mat2[3] = 4.0f;
mat2[7] = 0.00f;
mat2[11] = 84.00f;
mat2[15] = 1.97f;
simulator.ResetState();
simulator.set_xreg(0, reinterpret_cast<uintptr_t>(output));
simulator.set_xreg(1, reinterpret_cast<uintptr_t>(mat1));
simulator.set_xreg(2, reinterpret_cast<uintptr_t>(mat2));
simulator.RunFrom(masm.GetLabelAddress<Instruction*>(&neon_matrix_multiply));
// Print the 4x4 output matrix along with both 4x4 input matrices.
for (int i = 0; i < kRowSize; i++) {
printf(
"| %8.2f %8.2f %8.2f %8.2f | "
"| %8.2f %8.2f %8.2f %8.2f | "
"| %8.2f %8.2f %8.2f %8.2f |\n",
mat1[i],
mat1[4 + i],
mat1[8 + i],
mat1[12 + i],
mat2[i],
mat2[4 + i],
mat2[8 + i],
mat2[12 + i],
output[i],
output[4 + i],
output[8 + i],
output[12 + i]);
if (i == 0 || i == 2) {
printf(
"| | "
"| | "
"| |\n");
} else if (i == 1) {
printf(
"| | x "
"| | = "
"| |\n");
}
}
return 0;
}
#else
// Without the simulator there is nothing to test.
int main(void) { return 0; }
#endif // VIXL_INCLUDE_SIMULATOR
#endif // TEST_EXAMPLES