Merge "apf: Add immediate encoding tests for LI"

This commit is contained in:
Treehugger Robot
2018-04-20 01:09:33 +00:00
committed by Gerrit Code Review

View File

@@ -150,15 +150,24 @@ public class ApfTest {
assertVerdict(DROP, program, packet);
}
private void assertDataMemoryContents(
int expected, byte[] program, byte[] packet, byte[] data, byte[] expected_data)
throws IllegalInstructionException, Exception {
private void assertProgramEquals(byte[] expected, byte[] program) throws AssertionError {
// assertArrayEquals() would only print one byte, making debugging difficult.
if (!java.util.Arrays.equals(expected, program)) {
throw new AssertionError(
"\nexpected: " + HexDump.toHexString(expected) +
"\nactual: " + HexDump.toHexString(program));
}
}
private void assertDataMemoryContents(
int expected, byte[] program, byte[] packet, byte[] data, byte[] expected_data)
throws IllegalInstructionException, Exception {
assertReturnCodesEqual(expected, apfSimulate(program, packet, data, 0 /* filterAge */));
// assertArrayEquals() would only print one byte, making debugging difficult.
if (!java.util.Arrays.equals(expected_data, data)) {
throw new Exception(
"program: " + HexDump.toHexString(program) +
"\nprogram: " + HexDump.toHexString(program) +
"\ndata memory: " + HexDump.toHexString(data) +
"\nexpected: " + HexDump.toHexString(expected_data));
}
@@ -622,6 +631,64 @@ public class ApfTest {
}
}
/**
* Test that the generator emits immediates using the shortest possible encoding.
*/
@Test
public void testImmediateEncoding() throws IllegalInstructionException {
final int LI_OPCODE = 13 << 3;
ApfGenerator gen;
// 0-byte immediate: li R0, 0
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R0, 0);
assertProgramEquals(new byte[]{LI_OPCODE | (0 << 1)}, gen.generate());
// 1-byte immediate: li R0, 42
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R0, 42);
assertProgramEquals(new byte[]{LI_OPCODE | (1 << 1), 42}, gen.generate());
// 2-byte immediate: li R1, 0x1234
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R1, 0x1234);
assertProgramEquals(new byte[]{LI_OPCODE | (2 << 1) | 1 , 0x12, 0x34}, gen.generate());
// 4-byte immediate: li R0, 0x12345678
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R0, 0x12345678);
assertProgramEquals(
new byte[]{LI_OPCODE | (3 << 1), 0x12, 0x34, 0x56, 0x78},
gen.generate());
}
/**
* Test that the generator emits negative immediates using the shortest possible encoding.
*/
@Test
public void testNegativeImmediateEncoding() throws IllegalInstructionException {
final int LI_OPCODE = 13 << 3;
ApfGenerator gen;
// 1-byte negative immediate: li R0, -42
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R0, -42);
assertProgramEquals(new byte[]{LI_OPCODE | (1 << 1), -42}, gen.generate());
// 2-byte negative immediate: li R1, -0x1234
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R1, -0x1122);
assertProgramEquals(new byte[]{LI_OPCODE | (2 << 1) | 1, (byte)0xEE, (byte)0xDE},
gen.generate());
// 4-byte negative immediate: li R0, -0x11223344
gen = new ApfGenerator(3);
gen.addLoadImmediate(Register.R0, -0x11223344);
assertProgramEquals(
new byte[]{LI_OPCODE | (3 << 1), (byte)0xEE, (byte)0xDD, (byte)0xCC, (byte)0xBC},
gen.generate());
}
@Test
public void testApfDataWrite() throws IllegalInstructionException, Exception {
byte[] packet = new byte[MIN_PKT_SIZE];