llvm-project/llvm/unittests/IR/DemandedBitsTest.cpp

67 lines
2.4 KiB
C++

//===- DemandedBitsTest.cpp - DemandedBits tests --------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/DemandedBits.h"
#include "../Support/KnownBitsTest.h"
#include "llvm/Support/KnownBits.h"
#include "gtest/gtest.h"
using namespace llvm;
namespace {
template <typename Fn1, typename Fn2>
static void TestBinOpExhaustive(Fn1 PropagateFn, Fn2 EvalFn) {
unsigned Bits = 4;
unsigned Max = 1 << Bits;
ForeachKnownBits(Bits, [&](const KnownBits &Known1) {
ForeachKnownBits(Bits, [&](const KnownBits &Known2) {
for (unsigned AOut_ = 0; AOut_ < Max; AOut_++) {
APInt AOut(Bits, AOut_);
APInt AB1 = PropagateFn(0, AOut, Known1, Known2);
APInt AB2 = PropagateFn(1, AOut, Known1, Known2);
{
// If the propagator claims that certain known bits
// didn't matter, check it doesn't change its mind
// when they become unknown.
KnownBits Known1Redacted;
KnownBits Known2Redacted;
Known1Redacted.Zero = Known1.Zero & AB1;
Known1Redacted.One = Known1.One & AB1;
Known2Redacted.Zero = Known2.Zero & AB2;
Known2Redacted.One = Known2.One & AB2;
APInt AB1R = PropagateFn(0, AOut, Known1Redacted, Known2Redacted);
APInt AB2R = PropagateFn(1, AOut, Known1Redacted, Known2Redacted);
EXPECT_EQ(AB1, AB1R);
EXPECT_EQ(AB2, AB2R);
}
ForeachNumInKnownBits(Known1, [&](APInt Value1) {
ForeachNumInKnownBits(Known2, [&](APInt Value2) {
APInt ReferenceResult = EvalFn((Value1 & AB1), (Value2 & AB2));
APInt Result = EvalFn(Value1, Value2);
EXPECT_EQ(Result & AOut, ReferenceResult & AOut);
});
});
}
});
});
}
TEST(DemandedBitsTest, Add) {
TestBinOpExhaustive(DemandedBits::determineLiveOperandBitsAdd,
[](APInt N1, APInt N2) -> APInt { return N1 + N2; });
}
TEST(DemandedBitsTest, Sub) {
TestBinOpExhaustive(DemandedBits::determineLiveOperandBitsSub,
[](APInt N1, APInt N2) -> APInt { return N1 - N2; });
}
} // anonymous namespace