[llvm-branch-commits] [llvm] b0234d1 - Revert "[ADT] Refactor Bitset to Be More Constexpr-Usable (#172062)"
Michał Górny via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Sat Dec 20 12:22:41 PST 2025
Author: Michał Górny
Date: 2025-12-20T21:22:28+01:00
New Revision: b0234d1754ce21282d2d4f5508489bf39a1833cd
URL: https://github.com/llvm/llvm-project/commit/b0234d1754ce21282d2d4f5508489bf39a1833cd
DIFF: https://github.com/llvm/llvm-project/commit/b0234d1754ce21282d2d4f5508489bf39a1833cd.diff
LOG: Revert "[ADT] Refactor Bitset to Be More Constexpr-Usable (#172062)"
This reverts commit a71b1d2a385da0f691f76176ed4a13d35e1f970f.
Added:
Modified:
llvm/include/llvm/ADT/Bitset.h
llvm/unittests/ADT/BitsetTest.cpp
Removed:
################################################################################
diff --git a/llvm/include/llvm/ADT/Bitset.h b/llvm/include/llvm/ADT/Bitset.h
index 09c1239f15d2f..1d4cbf8306230 100644
--- a/llvm/include/llvm/ADT/Bitset.h
+++ b/llvm/include/llvm/ADT/Bitset.h
@@ -16,7 +16,7 @@
#ifndef LLVM_ADT_BITSET_H
#define LLVM_ADT_BITSET_H
-#include "llvm/ADT/STLExtras.h"
+#include <llvm/ADT/STLExtras.h>
#include <array>
#include <climits>
#include <cstdint>
@@ -31,10 +31,6 @@ class Bitset {
using BitWord = uintptr_t;
static constexpr unsigned BitwordBits = sizeof(BitWord) * CHAR_BIT;
- static constexpr unsigned RemainderNumBits = NumBits % BitwordBits;
- static constexpr BitWord RemainderMask =
- RemainderNumBits == 0 ? ~BitWord(0)
- : ((BitWord(1) << RemainderNumBits) - 1);
static_assert(BitwordBits == 64 || BitwordBits == 32,
"Unsupported word size");
@@ -42,16 +38,9 @@ class Bitset {
static constexpr unsigned NumWords =
(NumBits + BitwordBits - 1) / BitwordBits;
- // Returns the index of the last word (0-based). The last word may be
- // partially filled and requires masking to maintain the invariant that
- // unused high bits are always zero.
- static constexpr unsigned getLastWordIndex() { return NumWords - 1; }
-
using StorageType = std::array<BitWord, NumWords>;
StorageType Bits{};
- constexpr void maskLastWord() { Bits[getLastWordIndex()] &= RemainderMask; }
-
protected:
constexpr Bitset(const std::array<uint64_t, (NumBits + 63) / 64> &B) {
if constexpr (sizeof(BitWord) == sizeof(uint64_t)) {
@@ -63,13 +52,12 @@ class Bitset {
uint64_t Elt = B[I];
// On a 32-bit system the storage type will be 32-bit, so we may only
// need half of a uint64_t.
- for (size_t Offset = 0; Offset != 2 && BitsToAssign; ++Offset) {
- Bits[2 * I + Offset] = static_cast<uint32_t>(Elt >> (32 * Offset));
+ for (size_t offset = 0; offset != 2 && BitsToAssign; ++offset) {
+ Bits[2 * I + offset] = static_cast<uint32_t>(Elt >> (32 * offset));
BitsToAssign = BitsToAssign >= 32 ? BitsToAssign - 32 : 0;
}
}
}
- maskLastWord();
}
public:
@@ -79,11 +67,8 @@ class Bitset {
set(I);
}
- constexpr Bitset &set() {
- constexpr const BitWord AllOnes = ~BitWord(0);
- for (BitWord &B : Bits)
- B = AllOnes;
- maskLastWord();
+ Bitset &set() {
+ llvm::fill(Bits, -BitWord(0));
return *this;
}
@@ -111,24 +96,14 @@ class Bitset {
constexpr size_t size() const { return NumBits; }
- constexpr bool any() const {
+ bool any() const {
return llvm::any_of(Bits, [](BitWord I) { return I != 0; });
}
-
- constexpr bool none() const { return !any(); }
-
- constexpr bool all() const {
- constexpr const BitWord AllOnes = ~BitWord(0);
- for (unsigned I = 0; I < getLastWordIndex(); ++I)
- if (Bits[I] != AllOnes)
- return false;
- return Bits[getLastWordIndex()] == RemainderMask;
- }
-
- constexpr size_t count() const {
+ bool none() const { return !any(); }
+ size_t count() const {
size_t Count = 0;
- for (BitWord Word : Bits)
- Count += popcount(Word);
+ for (auto B : Bits)
+ Count += llvm::popcount(B);
return Count;
}
@@ -169,22 +144,18 @@ class Bitset {
constexpr Bitset operator~() const {
Bitset Result = *this;
- for (BitWord &B : Result.Bits)
+ for (auto &B : Result.Bits)
B = ~B;
- Result.maskLastWord();
return Result;
}
- constexpr bool operator==(const Bitset &RHS) const {
- for (unsigned I = 0; I < NumWords; ++I)
- if (Bits[I] != RHS.Bits[I])
- return false;
- return true;
+ bool operator==(const Bitset &RHS) const {
+ return std::equal(std::begin(Bits), std::end(Bits), std::begin(RHS.Bits));
}
- constexpr bool operator!=(const Bitset &RHS) const { return !(*this == RHS); }
+ bool operator!=(const Bitset &RHS) const { return !(*this == RHS); }
- constexpr bool operator<(const Bitset &Other) const {
+ bool operator < (const Bitset &Other) const {
for (unsigned I = 0, E = size(); I != E; ++I) {
bool LHS = test(I), RHS = Other.test(I);
if (LHS != RHS)
diff --git a/llvm/unittests/ADT/BitsetTest.cpp b/llvm/unittests/ADT/BitsetTest.cpp
index 678197e31a379..0ecd213d6a781 100644
--- a/llvm/unittests/ADT/BitsetTest.cpp
+++ b/llvm/unittests/ADT/BitsetTest.cpp
@@ -68,230 +68,4 @@ TEST(BitsetTest, Construction) {
EXPECT_TRUE(Test33.verifyValue(TestSingleVal));
Test33.verifyStorageSize(1, 2);
}
-
-TEST(BitsetTest, SetAndQuery) {
- // Test set() with all bits.
- Bitset<64> A;
- A.set();
- EXPECT_TRUE(A.all());
- EXPECT_TRUE(A.any());
- EXPECT_FALSE(A.none());
-
- static_assert(Bitset<64>().set().all());
- static_assert(Bitset<33>().set().all());
-
- // Test set() with single bit.
- Bitset<64> B;
- B.set(10);
- B.set(20);
- EXPECT_TRUE(B.test(10));
- EXPECT_TRUE(B.test(20));
- EXPECT_FALSE(B.test(15));
-
- static_assert(Bitset<64>().set(10).test(10));
- static_assert(Bitset<64>().set(0).set(63).test(0) &&
- Bitset<64>().set(0).set(63).test(63));
- static_assert(Bitset<33>().set(32).test(32));
- static_assert(Bitset<128>().set(64).set(127).test(64) &&
- Bitset<128>().set(64).set(127).test(127));
-
- // Test reset() with single bit.
- Bitset<64> C({10, 20, 30});
- C.reset(20);
- EXPECT_TRUE(C.test(10));
- EXPECT_FALSE(C.test(20));
- EXPECT_TRUE(C.test(30));
-
- static_assert(!Bitset<64>({10, 20}).reset(10).test(10));
- static_assert(Bitset<64>({10, 20}).reset(10).test(20));
- static_assert(!Bitset<96>({31, 32, 63}).reset(32).test(32));
- static_assert(Bitset<33>({0, 32}).reset(0).test(32));
-
- // Test flip() with single bit.
- Bitset<64> D({10, 20});
- D.flip(10);
- D.flip(30);
- EXPECT_FALSE(D.test(10));
- EXPECT_TRUE(D.test(20));
- EXPECT_TRUE(D.test(30));
-
- static_assert(!Bitset<64>({10, 20}).flip(10).test(10));
- static_assert(Bitset<64>({10, 20}).flip(30).test(30));
- static_assert(Bitset<100>({50, 99}).flip(50).test(99) &&
- !Bitset<100>({50, 99}).flip(50).test(50));
- static_assert(Bitset<33>().flip(32).test(32));
-
- // Test operator[].
- Bitset<64> E({5, 15, 25});
- EXPECT_TRUE(E[5]);
- EXPECT_FALSE(E[10]);
- EXPECT_TRUE(E[15]);
-
- static_assert(Bitset<64>({10, 20})[10]);
- static_assert(!Bitset<64>({10, 20})[15]);
- static_assert(Bitset<128>({127})[127]);
- static_assert(Bitset<96>({63, 64})[63] && Bitset<96>({63, 64})[64]);
-
- // Test size().
- EXPECT_EQ(A.size(), 64u);
- Bitset<33> F;
- EXPECT_EQ(F.size(), 33u);
-
- static_assert(Bitset<64>().size() == 64);
- static_assert(Bitset<128>().size() == 128);
- static_assert(Bitset<33>().size() == 33);
-
- // Test any() and none().
- static_assert(!Bitset<64>().any());
- static_assert(Bitset<64>().none());
- static_assert(Bitset<64>({10}).any());
- static_assert(!Bitset<64>({10}).none());
-}
-
-TEST(BitsetTest, ComparisonOperators) {
- // Test operator==.
- Bitset<64> A({10, 20, 30});
- Bitset<64> B({10, 20, 30});
- Bitset<64> C({10, 20, 31});
- EXPECT_TRUE(A == B);
- EXPECT_FALSE(A == C);
-
- static_assert(Bitset<64>({10, 20}) == Bitset<64>({10, 20}));
- static_assert(Bitset<64>({10, 20}) != Bitset<64>({10, 21}));
-
- // Test operator< (lexicographic comparison, bit 0 is least significant).
- static_assert(Bitset<64>({5, 11}) <
- Bitset<64>({5, 10})); // At bit 10: A=0, B=1.
- static_assert(!(Bitset<64>({5, 10}) < Bitset<64>({5, 10})));
-}
-
-TEST(BitsetTest, BitwiseNot) {
- // Test operator~.
- Bitset<64> A;
- A.set();
- Bitset<64> B = ~A;
- EXPECT_TRUE(B.none());
-
- static_assert((~Bitset<64>()).all());
- static_assert((~Bitset<64>().set()).none());
- static_assert((~Bitset<33>().set()).none());
-}
-
-TEST(BitsetTest, BitwiseOperators) {
- // Test operator&.
- Bitset<64> A({10, 20, 30});
- Bitset<64> B({20, 30, 40});
- Bitset<64> Result1 = A & B;
- EXPECT_FALSE(Result1.test(10));
- EXPECT_TRUE(Result1.test(20));
- EXPECT_TRUE(Result1.test(30));
- EXPECT_FALSE(Result1.test(40));
- EXPECT_EQ(Result1.count(), 2u);
-
- static_assert((Bitset<64>({10, 20}) & Bitset<64>({20, 30})).test(20));
- static_assert(!(Bitset<64>({10, 20}) & Bitset<64>({20, 30})).test(10));
- static_assert((Bitset<64>({10, 20}) & Bitset<64>({20, 30})).count() == 1);
- static_assert(
- (Bitset<96>({31, 32, 63, 64}) & Bitset<96>({32, 64, 95})).count() == 2);
- static_assert((Bitset<33>({0, 32}) & Bitset<33>({32})).test(32));
-
- // Test operator&=.
- Bitset<64> C({10, 20, 30});
- C &= Bitset<64>({20, 30, 40});
- EXPECT_FALSE(C.test(10));
- EXPECT_TRUE(C.test(20));
- EXPECT_TRUE(C.test(30));
- EXPECT_FALSE(C.test(40));
-
- constexpr Bitset<64> TestAnd = [] {
- Bitset<64> X({10, 20, 30});
- X &= Bitset<64>({20, 30, 40});
- return X;
- }();
- static_assert(TestAnd.test(20) && TestAnd.test(30) && !TestAnd.test(10));
-
- constexpr Bitset<100> TestAnd100 = [] {
- Bitset<100> X({10, 50, 99});
- X &= Bitset<100>({50, 99});
- return X;
- }();
- static_assert(TestAnd100.count() == 2 && TestAnd100.test(50) &&
- TestAnd100.test(99));
-
- // Test operator|.
- Bitset<64> D({10, 20});
- Bitset<64> E({20, 30});
- Bitset<64> Result2 = D | E;
- EXPECT_TRUE(Result2.test(10));
- EXPECT_TRUE(Result2.test(20));
- EXPECT_TRUE(Result2.test(30));
- EXPECT_EQ(Result2.count(), 3u);
-
- static_assert((Bitset<64>({10}) | Bitset<64>({20})).count() == 2);
- static_assert((Bitset<128>({0, 64, 127}) | Bitset<128>({64, 100})).count() ==
- 4);
- static_assert((Bitset<33>({0, 16}) | Bitset<33>({16, 32})).count() == 3);
-
- // Test operator|=.
- Bitset<64> F({10, 20});
- F |= Bitset<64>({20, 30});
- EXPECT_TRUE(F.test(10));
- EXPECT_TRUE(F.test(20));
- EXPECT_TRUE(F.test(30));
-
- constexpr Bitset<64> TestOr = [] {
- Bitset<64> X({10});
- X |= Bitset<64>({20});
- return X;
- }();
- static_assert(TestOr.test(10) && TestOr.test(20));
-
- constexpr Bitset<96> TestOr96 = [] {
- Bitset<96> X({31, 63});
- X |= Bitset<96>({32, 64});
- return X;
- }();
- static_assert(TestOr96.count() == 4);
-
- // Test operator^.
- Bitset<64> G({10, 20, 30});
- Bitset<64> H({20, 30, 40});
- Bitset<64> Result3 = G ^ H;
- EXPECT_TRUE(Result3.test(10));
- EXPECT_FALSE(Result3.test(20));
- EXPECT_FALSE(Result3.test(30));
- EXPECT_TRUE(Result3.test(40));
- EXPECT_EQ(Result3.count(), 2u);
-
- static_assert((Bitset<64>({10, 20}) ^ Bitset<64>({20, 30})).test(10));
- static_assert(!(Bitset<64>({10, 20}) ^ Bitset<64>({20, 30})).test(20));
- static_assert((Bitset<64>({10, 20}) ^ Bitset<64>({20, 30})).test(30));
- static_assert((Bitset<64>({10, 20}) ^ Bitset<64>({20, 30})).count() == 2);
- static_assert((Bitset<100>({0, 50, 99}) ^ Bitset<100>({50})).count() == 2);
- static_assert((Bitset<33>({0, 32}) ^ Bitset<33>({0, 16})).count() == 2);
-
- // Test operator^=.
- Bitset<64> I({10, 20, 30});
- I ^= Bitset<64>({20, 30, 40});
- EXPECT_TRUE(I.test(10));
- EXPECT_FALSE(I.test(20));
- EXPECT_FALSE(I.test(30));
- EXPECT_TRUE(I.test(40));
-
- constexpr Bitset<64> TestXor = [] {
- Bitset<64> X({10, 20});
- X ^= Bitset<64>({20, 30});
- return X;
- }();
- static_assert(TestXor.test(10) && !TestXor.test(20) && TestXor.test(30));
-
- constexpr Bitset<128> TestXor128 = [] {
- Bitset<128> X({0, 64, 127});
- X ^= Bitset<128>({64});
- return X;
- }();
- static_assert(TestXor128.count() == 2 && TestXor128.test(0) &&
- TestXor128.test(127));
-}
-
} // namespace
More information about the llvm-branch-commits
mailing list