[llvm] r231043 - LowerBitSets: Use byte arrays instead of bit sets to represent in-memory bit sets.
Peter Collingbourne
peter at pcc.me.uk
Mon Mar 2 16:49:28 PST 2015
Author: pcc
Date: Mon Mar 2 18:49:28 2015
New Revision: 231043
URL: http://llvm.org/viewvc/llvm-project?rev=231043&view=rev
Log:
LowerBitSets: Use byte arrays instead of bit sets to represent in-memory bit sets.
By loading from indexed offsets into a byte array and applying a mask, a
program can test bits from the bit set with a relatively short instruction
sequence. For example, suppose we have 15 bit sets to lay out:
A (16 bits), B (15 bits), C (14 bits), D (13 bits), E (12 bits),
F (11 bits), G (10 bits), H (9 bits), I (7 bits), J (6 bits), K (5 bits),
L (4 bits), M (3 bits), N (2 bits), O (1 bit)
These bits can be laid out in a 16-byte array like this:
Byte Offset
0123456789ABCDEF
Bit
7 HHHHHHHHHIIIIIII
6 GGGGGGGGGGJJJJJJ
5 FFFFFFFFFFFKKKKK
4 EEEEEEEEEEEELLLL
3 DDDDDDDDDDDDDMMM
2 CCCCCCCCCCCCCCNN
1 BBBBBBBBBBBBBBBO
0 AAAAAAAAAAAAAAAA
For example, to test bit X of A, we evaluate ((bits[X] & 1) != 0), or to
test bit X of I, we evaluate ((bits[9 + X] & 0x80) != 0). This can be done
in 1-2 machine instructions on x86, or 4-6 instructions on ARM.
This uses the LPT multiprocessor scheduling algorithm to lay out the bits
efficiently.
Saves ~450KB of instructions in a recent build of Chromium.
Differential Revision: http://reviews.llvm.org/D7954
Modified:
llvm/trunk/include/llvm/Transforms/IPO/LowerBitSets.h
llvm/trunk/lib/Transforms/IPO/LowerBitSets.cpp
llvm/trunk/test/Transforms/LowerBitSets/simple.ll
llvm/trunk/unittests/Transforms/IPO/LowerBitSets.cpp
Modified: llvm/trunk/include/llvm/Transforms/IPO/LowerBitSets.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/IPO/LowerBitSets.h?rev=231043&r1=231042&r2=231043&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/IPO/LowerBitSets.h (original)
+++ llvm/trunk/include/llvm/Transforms/IPO/LowerBitSets.h Mon Mar 2 18:49:28 2015
@@ -30,8 +30,8 @@ class GlobalVariable;
class Value;
struct BitSetInfo {
- // The actual bitset.
- std::vector<uint8_t> Bits;
+ // The indices of the set bits in the bitset.
+ std::set<uint64_t> Bits;
// The byte offset into the combined global represented by the bitset.
uint64_t ByteOffset;
@@ -45,18 +45,11 @@ struct BitSetInfo {
unsigned AlignLog2;
bool isSingleOffset() const {
- return Bits.size() == 1 && Bits[0] == 1;
+ return Bits.size() == 1;
}
bool isAllOnes() const {
- for (unsigned I = 0; I != Bits.size() - 1; ++I)
- if (Bits[I] != 0xFF)
- return false;
-
- if (BitSize % 8 == 0)
- return Bits[Bits.size() - 1] == 0xFF;
-
- return Bits[Bits.size() - 1] == (1 << (BitSize % 8)) - 1;
+ return Bits.size() == BitSize;
}
bool containsGlobalOffset(uint64_t Offset) const;
@@ -64,7 +57,6 @@ struct BitSetInfo {
bool containsValue(const DataLayout *DL,
const DenseMap<GlobalVariable *, uint64_t> &GlobalLayout,
Value *V, uint64_t COffset = 0) const;
-
};
struct BitSetBuilder {
@@ -148,6 +140,59 @@ struct GlobalLayoutBuilder {
void addFragment(const std::set<uint64_t> &F);
};
+/// This class is used to build a byte array containing overlapping bit sets. By
+/// loading from indexed offsets into the byte array and applying a mask, a
+/// program can test bits from the bit set with a relatively short instruction
+/// sequence. For example, suppose we have 15 bit sets to lay out:
+///
+/// A (16 bits), B (15 bits), C (14 bits), D (13 bits), E (12 bits),
+/// F (11 bits), G (10 bits), H (9 bits), I (7 bits), J (6 bits), K (5 bits),
+/// L (4 bits), M (3 bits), N (2 bits), O (1 bit)
+///
+/// These bits can be laid out in a 16-byte array like this:
+///
+/// Byte Offset
+/// 0123456789ABCDEF
+/// Bit
+/// 7 HHHHHHHHHIIIIIII
+/// 6 GGGGGGGGGGJJJJJJ
+/// 5 FFFFFFFFFFFKKKKK
+/// 4 EEEEEEEEEEEELLLL
+/// 3 DDDDDDDDDDDDDMMM
+/// 2 CCCCCCCCCCCCCCNN
+/// 1 BBBBBBBBBBBBBBBO
+/// 0 AAAAAAAAAAAAAAAA
+///
+/// For example, to test bit X of A, we evaluate ((bits[X] & 1) != 0), or to
+/// test bit X of I, we evaluate ((bits[9 + X] & 0x80) != 0). This can be done
+/// in 1-2 machine instructions on x86, or 4-6 instructions on ARM.
+///
+/// This is a byte array, rather than (say) a 2-byte array or a 4-byte array,
+/// because for one thing it gives us better packing (the more bins there are,
+/// the less evenly they will be filled), and for another, the instruction
+/// sequences can be slightly shorter, both on x86 and ARM.
+struct ByteArrayBuilder {
+ /// The byte array built so far.
+ std::vector<uint8_t> Bytes;
+
+ enum { BitsPerByte = 8 };
+
+ /// The number of bytes allocated so far for each of the bits.
+ uint64_t BitAllocs[BitsPerByte];
+
+ ByteArrayBuilder() {
+ memset(BitAllocs, 0, sizeof(BitAllocs));
+ }
+
+ /// Allocate BitSize bits in the byte array where Bits contains the bits to
+ /// set. AllocByteOffset is set to the offset within the byte array and
+ /// AllocMask is set to the bitmask for those bits. This uses the LPT (Longest
+ /// Processing Time) multiprocessor scheduling algorithm to lay out the bits
+ /// efficiently; the pass allocates bit sets in decreasing size order.
+ void allocate(const std::set<uint64_t> &Bits, uint64_t BitSize,
+ uint64_t &AllocByteOffset, uint8_t &AllocMask);
+};
+
} // namespace llvm
#endif
Modified: llvm/trunk/lib/Transforms/IPO/LowerBitSets.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/LowerBitSets.cpp?rev=231043&r1=231042&r2=231043&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/LowerBitSets.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/LowerBitSets.cpp Mon Mar 2 18:49:28 2015
@@ -31,7 +31,9 @@ using namespace llvm;
#define DEBUG_TYPE "lowerbitsets"
-STATISTIC(NumBitSetsCreated, "Number of bitsets created");
+STATISTIC(ByteArraySizeBits, "Byte array size in bits");
+STATISTIC(ByteArraySizeBytes, "Byte array size in bytes");
+STATISTIC(NumByteArraysCreated, "Number of byte arrays created");
STATISTIC(NumBitSetCallsLowered, "Number of bitset calls lowered");
STATISTIC(NumBitSetDisjointSets, "Number of disjoint sets of bitsets");
@@ -46,7 +48,7 @@ bool BitSetInfo::containsGlobalOffset(ui
if (BitOffset >= BitSize)
return false;
- return (Bits[BitOffset / 8] >> (BitOffset % 8)) & 1;
+ return Bits.count(BitOffset);
}
bool BitSetInfo::containsValue(
@@ -101,18 +103,15 @@ BitSetInfo BitSetBuilder::build() {
BSI.ByteOffset = Min;
BSI.AlignLog2 = 0;
- // FIXME: Can probably do something smarter if all offsets are 0.
if (Mask != 0)
BSI.AlignLog2 = countTrailingZeros(Mask, ZB_Undefined);
// Build the compressed bitset while normalizing the offsets against the
// computed alignment.
BSI.BitSize = ((Max - Min) >> BSI.AlignLog2) + 1;
- uint64_t ByteSize = (BSI.BitSize + 7) / 8;
- BSI.Bits.resize(ByteSize);
for (uint64_t Offset : Offsets) {
Offset >>= BSI.AlignLog2;
- BSI.Bits[Offset / 8] |= 1 << (Offset % 8);
+ BSI.Bits.insert(Offset);
}
return BSI;
@@ -147,14 +146,46 @@ void GlobalLayoutBuilder::addFragment(co
FragmentMap[ObjIndex] = FragmentIndex;
}
+void ByteArrayBuilder::allocate(const std::set<uint64_t> &Bits,
+ uint64_t BitSize, uint64_t &AllocByteOffset,
+ uint8_t &AllocMask) {
+ // Find the smallest current allocation.
+ unsigned Bit = 0;
+ for (unsigned I = 1; I != BitsPerByte; ++I)
+ if (BitAllocs[I] < BitAllocs[Bit])
+ Bit = I;
+
+ AllocByteOffset = BitAllocs[Bit];
+
+ // Add our size to it.
+ unsigned ReqSize = AllocByteOffset + BitSize;
+ BitAllocs[Bit] = ReqSize;
+ if (Bytes.size() < ReqSize)
+ Bytes.resize(ReqSize);
+
+ // Set our bits.
+ AllocMask = 1 << Bit;
+ for (uint64_t B : Bits)
+ Bytes[AllocByteOffset + B] |= AllocMask;
+}
+
namespace {
+struct ByteArrayInfo {
+ std::set<uint64_t> Bits;
+ uint64_t BitSize;
+ GlobalVariable *ByteArray;
+ Constant *Mask;
+};
+
struct LowerBitSets : public ModulePass {
static char ID;
LowerBitSets() : ModulePass(ID) {
initializeLowerBitSetsPass(*PassRegistry::getPassRegistry());
}
+ Module *M;
+
const DataLayout *DL;
IntegerType *Int1Ty;
IntegerType *Int8Ty;
@@ -169,20 +200,23 @@ struct LowerBitSets : public ModulePass
// Mapping from bitset mdstrings to the call sites that test them.
DenseMap<MDString *, std::vector<CallInst *>> BitSetTestCallSites;
+ std::vector<ByteArrayInfo> ByteArrayInfos;
+
BitSetInfo
buildBitSet(MDString *BitSet,
const DenseMap<GlobalVariable *, uint64_t> &GlobalLayout);
- Value *createBitSetTest(IRBuilder<> &B, const BitSetInfo &BSI,
- GlobalVariable *BitSetGlobal, Value *BitOffset);
+ ByteArrayInfo *createByteArray(BitSetInfo &BSI);
+ void allocateByteArrays();
+ Value *createBitSetTest(IRBuilder<> &B, BitSetInfo &BSI, ByteArrayInfo *&BAI,
+ Value *BitOffset);
Value *
- lowerBitSetCall(CallInst *CI, const BitSetInfo &BSI,
- GlobalVariable *BitSetGlobal, GlobalVariable *CombinedGlobal,
+ lowerBitSetCall(CallInst *CI, BitSetInfo &BSI, ByteArrayInfo *&BAI,
+ GlobalVariable *CombinedGlobal,
const DenseMap<GlobalVariable *, uint64_t> &GlobalLayout);
- void buildBitSetsFromGlobals(Module &M,
- const std::vector<MDString *> &BitSets,
+ void buildBitSetsFromGlobals(const std::vector<MDString *> &BitSets,
const std::vector<GlobalVariable *> &Globals);
- bool buildBitSets(Module &M);
- bool eraseBitSetMetadata(Module &M);
+ bool buildBitSets();
+ bool eraseBitSetMetadata();
bool doInitialization(Module &M) override;
bool runOnModule(Module &M) override;
@@ -198,19 +232,21 @@ char LowerBitSets::ID = 0;
ModulePass *llvm::createLowerBitSetsPass() { return new LowerBitSets; }
-bool LowerBitSets::doInitialization(Module &M) {
- DL = M.getDataLayout();
+bool LowerBitSets::doInitialization(Module &Mod) {
+ M = &Mod;
+
+ DL = M->getDataLayout();
if (!DL)
report_fatal_error("Data layout required");
- Int1Ty = Type::getInt1Ty(M.getContext());
- Int8Ty = Type::getInt8Ty(M.getContext());
- Int32Ty = Type::getInt32Ty(M.getContext());
+ Int1Ty = Type::getInt1Ty(M->getContext());
+ Int8Ty = Type::getInt8Ty(M->getContext());
+ Int32Ty = Type::getInt32Ty(M->getContext());
Int32PtrTy = PointerType::getUnqual(Int32Ty);
- Int64Ty = Type::getInt64Ty(M.getContext());
- IntPtrTy = DL->getIntPtrType(M.getContext(), 0);
+ Int64Ty = Type::getInt64Ty(M->getContext());
+ IntPtrTy = DL->getIntPtrType(M->getContext(), 0);
- BitSetNM = M.getNamedMetadata("llvm.bitsets");
+ BitSetNM = M->getNamedMetadata("llvm.bitsets");
BitSetTestCallSites.clear();
@@ -259,52 +295,113 @@ static Value *createMaskedBitTest(IRBuil
return B.CreateICmpNE(MaskedBits, ConstantInt::get(BitsType, 0));
}
+ByteArrayInfo *LowerBitSets::createByteArray(BitSetInfo &BSI) {
+ // Create globals to stand in for byte arrays and masks. These never actually
+ // get initialized, we RAUW and erase them later in allocateByteArrays() once
+ // we know the offset and mask to use.
+ auto ByteArrayGlobal = new GlobalVariable(
+ *M, Int8Ty, /*isConstant=*/true, GlobalValue::PrivateLinkage, nullptr);
+ auto MaskGlobal = new GlobalVariable(
+ *M, Int8Ty, /*isConstant=*/true, GlobalValue::PrivateLinkage, nullptr);
+
+ ByteArrayInfos.emplace_back();
+ ByteArrayInfo *BAI = &ByteArrayInfos.back();
+
+ BAI->Bits = BSI.Bits;
+ BAI->BitSize = BSI.BitSize;
+ BAI->ByteArray = ByteArrayGlobal;
+ BAI->Mask = ConstantExpr::getPtrToInt(MaskGlobal, Int8Ty);
+ return BAI;
+}
+
+void LowerBitSets::allocateByteArrays() {
+ std::stable_sort(ByteArrayInfos.begin(), ByteArrayInfos.end(),
+ [](const ByteArrayInfo &BAI1, const ByteArrayInfo &BAI2) {
+ return BAI1.BitSize > BAI2.BitSize;
+ });
+
+ std::vector<uint64_t> ByteArrayOffsets(ByteArrayInfos.size());
+
+ ByteArrayBuilder BAB;
+ for (unsigned I = 0; I != ByteArrayInfos.size(); ++I) {
+ ByteArrayInfo *BAI = &ByteArrayInfos[I];
+
+ uint8_t Mask;
+ BAB.allocate(BAI->Bits, BAI->BitSize, ByteArrayOffsets[I], Mask);
+
+ BAI->Mask->replaceAllUsesWith(ConstantInt::get(Int8Ty, Mask));
+ cast<GlobalVariable>(BAI->Mask->getOperand(0))->eraseFromParent();
+ }
+
+ Constant *ByteArrayConst = ConstantDataArray::get(M->getContext(), BAB.Bytes);
+ auto ByteArray =
+ new GlobalVariable(*M, ByteArrayConst->getType(), /*isConstant=*/true,
+ GlobalValue::PrivateLinkage, ByteArrayConst);
+
+ for (unsigned I = 0; I != ByteArrayInfos.size(); ++I) {
+ ByteArrayInfo *BAI = &ByteArrayInfos[I];
+
+ Constant *Idxs[] = {ConstantInt::get(IntPtrTy, 0),
+ ConstantInt::get(IntPtrTy, ByteArrayOffsets[I])};
+ Constant *GEP = ConstantExpr::getInBoundsGetElementPtr(ByteArray, Idxs);
+
+ // Create an alias instead of RAUW'ing the gep directly. On x86 this ensures
+ // that the pc-relative displacement is folded into the lea instead of the
+ // test instruction getting another displacement.
+ GlobalAlias *Alias = GlobalAlias::create(
+ Int8Ty, 0, GlobalValue::PrivateLinkage, "bits", GEP, M);
+ BAI->ByteArray->replaceAllUsesWith(Alias);
+ BAI->ByteArray->eraseFromParent();
+ }
+
+ ByteArraySizeBits = BAB.BitAllocs[0] + BAB.BitAllocs[1] + BAB.BitAllocs[2] +
+ BAB.BitAllocs[3] + BAB.BitAllocs[4] + BAB.BitAllocs[5] +
+ BAB.BitAllocs[6] + BAB.BitAllocs[7];
+ ByteArraySizeBytes = BAB.Bytes.size();
+}
+
/// Build a test that bit BitOffset is set in BSI, where
/// BitSetGlobal is a global containing the bits in BSI.
-Value *LowerBitSets::createBitSetTest(IRBuilder<> &B, const BitSetInfo &BSI,
- GlobalVariable *BitSetGlobal,
- Value *BitOffset) {
- if (BSI.Bits.size() <= 8) {
+Value *LowerBitSets::createBitSetTest(IRBuilder<> &B, BitSetInfo &BSI,
+ ByteArrayInfo *&BAI, Value *BitOffset) {
+ if (BSI.BitSize <= 64) {
// If the bit set is sufficiently small, we can avoid a load by bit testing
// a constant.
IntegerType *BitsTy;
- if (BSI.Bits.size() <= 4)
+ if (BSI.BitSize <= 32)
BitsTy = Int32Ty;
else
BitsTy = Int64Ty;
uint64_t Bits = 0;
- for (auto I = BSI.Bits.rbegin(), E = BSI.Bits.rend(); I != E; ++I) {
- Bits <<= 8;
- Bits |= *I;
- }
+ for (auto Bit : BSI.Bits)
+ Bits |= uint64_t(1) << Bit;
Constant *BitsConst = ConstantInt::get(BitsTy, Bits);
return createMaskedBitTest(B, BitsConst, BitOffset);
} else {
- // TODO: We might want to use the memory variant of the bt instruction
- // with the previously computed bit offset at -Os. This instruction does
- // exactly what we want but has been benchmarked as being slower than open
- // coding the load+bt.
- Value *BitSetGlobalOffset =
- B.CreateLShr(BitOffset, ConstantInt::get(IntPtrTy, 5));
- Value *BitSetEntryAddr = B.CreateGEP(
- ConstantExpr::getBitCast(BitSetGlobal, Int32PtrTy), BitSetGlobalOffset);
- Value *BitSetEntry = B.CreateLoad(BitSetEntryAddr);
+ if (!BAI) {
+ ++NumByteArraysCreated;
+ BAI = createByteArray(BSI);
+ }
+
+ Value *ByteAddr = B.CreateGEP(BAI->ByteArray, BitOffset);
+ Value *Byte = B.CreateLoad(ByteAddr);
- return createMaskedBitTest(B, BitSetEntry, BitOffset);
+ Value *ByteAndMask = B.CreateAnd(Byte, BAI->Mask);
+ return B.CreateICmpNE(ByteAndMask, ConstantInt::get(Int8Ty, 0));
}
}
/// Lower a llvm.bitset.test call to its implementation. Returns the value to
/// replace the call with.
Value *LowerBitSets::lowerBitSetCall(
- CallInst *CI, const BitSetInfo &BSI, GlobalVariable *BitSetGlobal,
+ CallInst *CI, BitSetInfo &BSI, ByteArrayInfo *&BAI,
GlobalVariable *CombinedGlobal,
const DenseMap<GlobalVariable *, uint64_t> &GlobalLayout) {
Value *Ptr = CI->getArgOperand(0);
if (BSI.containsValue(DL, GlobalLayout, Ptr))
- return ConstantInt::getTrue(BitSetGlobal->getParent()->getContext());
+ return ConstantInt::getTrue(CombinedGlobal->getParent()->getContext());
Constant *GlobalAsInt = ConstantExpr::getPtrToInt(CombinedGlobal, IntPtrTy);
Constant *OffsetedGlobalAsInt = ConstantExpr::getAdd(
@@ -353,7 +450,7 @@ Value *LowerBitSets::lowerBitSetCall(
// Now that we know that the offset is in range and aligned, load the
// appropriate bit from the bitset.
- Value *Bit = createBitSetTest(ThenB, BSI, BitSetGlobal, BitOffset);
+ Value *Bit = createBitSetTest(ThenB, BSI, BAI, BitOffset);
// The value we want is 0 if we came directly from the initial block
// (having failed the range or alignment checks), or the loaded bit if
@@ -368,7 +465,6 @@ Value *LowerBitSets::lowerBitSetCall(
/// Given a disjoint set of bitsets and globals, layout the globals, build the
/// bit sets and lower the llvm.bitset.test calls.
void LowerBitSets::buildBitSetsFromGlobals(
- Module &M,
const std::vector<MDString *> &BitSets,
const std::vector<GlobalVariable *> &Globals) {
// Build a new global with the combined contents of the referenced globals.
@@ -391,9 +487,9 @@ void LowerBitSets::buildBitSetsFromGloba
}
if (!GlobalInits.empty())
GlobalInits.pop_back();
- Constant *NewInit = ConstantStruct::getAnon(M.getContext(), GlobalInits);
+ Constant *NewInit = ConstantStruct::getAnon(M->getContext(), GlobalInits);
auto CombinedGlobal =
- new GlobalVariable(M, NewInit->getType(), /*isConstant=*/true,
+ new GlobalVariable(*M, NewInit->getType(), /*isConstant=*/true,
GlobalValue::PrivateLinkage, NewInit);
const StructLayout *CombinedGlobalLayout =
@@ -410,18 +506,12 @@ void LowerBitSets::buildBitSetsFromGloba
// Build the bitset.
BitSetInfo BSI = buildBitSet(BS, GlobalLayout);
- // Create a global in which to store it.
- ++NumBitSetsCreated;
- Constant *BitsConst = ConstantDataArray::get(M.getContext(), BSI.Bits);
- auto BitSetGlobal = new GlobalVariable(
- M, BitsConst->getType(), /*isConstant=*/true,
- GlobalValue::PrivateLinkage, BitsConst, BS->getString() + ".bits");
+ ByteArrayInfo *BAI = 0;
// Lower each call to llvm.bitset.test for this bitset.
for (CallInst *CI : BitSetTestCallSites[BS]) {
++NumBitSetCallsLowered;
- Value *Lowered =
- lowerBitSetCall(CI, BSI, BitSetGlobal, CombinedGlobal, GlobalLayout);
+ Value *Lowered = lowerBitSetCall(CI, BSI, BAI, CombinedGlobal, GlobalLayout);
CI->replaceAllUsesWith(Lowered);
CI->eraseFromParent();
}
@@ -439,7 +529,7 @@ void LowerBitSets::buildBitSetsFromGloba
GlobalAlias *GAlias = GlobalAlias::create(
Globals[I]->getType()->getElementType(),
Globals[I]->getType()->getAddressSpace(), Globals[I]->getLinkage(),
- "", CombinedGlobalElemPtr, &M);
+ "", CombinedGlobalElemPtr, M);
GAlias->takeName(Globals[I]);
Globals[I]->replaceAllUsesWith(GAlias);
Globals[I]->eraseFromParent();
@@ -447,9 +537,9 @@ void LowerBitSets::buildBitSetsFromGloba
}
/// Lower all bit sets in this module.
-bool LowerBitSets::buildBitSets(Module &M) {
+bool LowerBitSets::buildBitSets() {
Function *BitSetTestFunc =
- M.getFunction(Intrinsic::getName(Intrinsic::bitset_test));
+ M->getFunction(Intrinsic::getName(Intrinsic::bitset_test));
if (!BitSetTestFunc)
return false;
@@ -591,22 +681,24 @@ bool LowerBitSets::buildBitSets(Module &
});
// Build the bitsets from this disjoint set.
- buildBitSetsFromGlobals(M, BitSets, OrderedGlobals);
+ buildBitSetsFromGlobals(BitSets, OrderedGlobals);
}
+ allocateByteArrays();
+
return true;
}
-bool LowerBitSets::eraseBitSetMetadata(Module &M) {
+bool LowerBitSets::eraseBitSetMetadata() {
if (!BitSetNM)
return false;
- M.eraseNamedMetadata(BitSetNM);
+ M->eraseNamedMetadata(BitSetNM);
return true;
}
bool LowerBitSets::runOnModule(Module &M) {
- bool Changed = buildBitSets(M);
- Changed |= eraseBitSetMetadata(M);
+ bool Changed = buildBitSets();
+ Changed |= eraseBitSetMetadata();
return Changed;
}
Modified: llvm/trunk/test/Transforms/LowerBitSets/simple.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LowerBitSets/simple.ll?rev=231043&r1=231042&r2=231043&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/LowerBitSets/simple.ll (original)
+++ llvm/trunk/test/Transforms/LowerBitSets/simple.ll Mon Mar 2 18:49:28 2015
@@ -9,8 +9,9 @@ target datalayout = "e-p:32:32"
@c = constant i32 3
@d = constant [2 x i32] [i32 4, i32 5]
+; CHECK: [[BA:@[^ ]*]] = private constant [68 x i8] c"\03\01\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\02\00\01"
+
; Offset 0, 4 byte alignment
-; CHECK: @bitset1.bits = private constant [9 x i8] c"\03\00\00\00\00\00\00\00\08"
!0 = !{!"bitset1", i32* @a, i32 0}
; CHECK-NODISCARD-DAG: !{!"bitset1", i32* @a, i32 0}
!1 = !{!"bitset1", [63 x i32]* @b, i32 0}
@@ -19,14 +20,12 @@ target datalayout = "e-p:32:32"
; CHECK-NODISCARD-DAG: !{!"bitset1", [2 x i32]* @d, i32 4}
; Offset 4, 256 byte alignment
-; CHECK: @bitset2.bits = private constant [1 x i8] c"\03"
!3 = !{!"bitset2", [63 x i32]* @b, i32 0}
; CHECK-NODISCARD-DAG: !{!"bitset2", [63 x i32]* @b, i32 0}
!4 = !{!"bitset2", i32* @c, i32 0}
; CHECK-NODISCARD-DAG: !{!"bitset2", i32* @c, i32 0}
; Offset 0, 4 byte alignment
-; CHECK: @bitset3.bits = private constant [9 x i8] c"\01\00\00\00\00\00\00\00\02"
!5 = !{!"bitset3", i32* @a, i32 0}
; CHECK-NODISCARD-DAG: !{!"bitset3", i32* @a, i32 0}
!6 = !{!"bitset3", i32* @c, i32 0}
@@ -43,6 +42,9 @@ target datalayout = "e-p:32:32"
; CHECK: @c = alias getelementptr inbounds ({ i32, [0 x i8], [63 x i32], [4 x i8], i32, [0 x i8], [2 x i32] }* [[G]], i32 0, i32 4)
; CHECK: @d = alias getelementptr inbounds ({ i32, [0 x i8], [63 x i32], [4 x i8], i32, [0 x i8], [2 x i32] }* [[G]], i32 0, i32 6)
+; CHECK: @bits = private alias getelementptr inbounds ([68 x i8]* [[BA]], i32 0, i32 0)
+; CHECK: @bits1 = private alias getelementptr inbounds ([68 x i8]* [[BA]], i32 0, i32 0)
+
declare i1 @llvm.bitset.test(i8* %ptr, metadata %bitset) nounwind readnone
; CHECK: @foo(i32* [[A0:%[^ ]*]])
@@ -59,15 +61,12 @@ define i1 @foo(i32* %p) {
; CHECK: [[R6:%[^ ]*]] = icmp ult i32 [[R5]], 68
; CHECK: br i1 [[R6]]
- ; CHECK: [[R8:%[^ ]*]] = lshr i32 [[R5]], 5
- ; CHECK: [[R9:%[^ ]*]] = getelementptr i32, i32* bitcast ([9 x i8]* @bitset1.bits to i32*), i32 [[R8]]
- ; CHECK: [[R10:%[^ ]*]] = load i32, i32* [[R9]]
- ; CHECK: [[R11:%[^ ]*]] = and i32 [[R5]], 31
- ; CHECK: [[R12:%[^ ]*]] = shl i32 1, [[R11]]
- ; CHECK: [[R13:%[^ ]*]] = and i32 [[R10]], [[R12]]
- ; CHECK: [[R14:%[^ ]*]] = icmp ne i32 [[R13]], 0
+ ; CHECK: [[R8:%[^ ]*]] = getelementptr i8, i8* @bits, i32 [[R5]]
+ ; CHECK: [[R9:%[^ ]*]] = load i8, i8* [[R8]]
+ ; CHECK: [[R10:%[^ ]*]] = and i8 [[R9]], 1
+ ; CHECK: [[R11:%[^ ]*]] = icmp ne i8 [[R10]], 0
- ; CHECK: [[R16:%[^ ]*]] = phi i1 [ false, {{%[^ ]*}} ], [ [[R14]], {{%[^ ]*}} ]
+ ; CHECK: [[R16:%[^ ]*]] = phi i1 [ false, {{%[^ ]*}} ], [ [[R11]], {{%[^ ]*}} ]
%x = call i1 @llvm.bitset.test(i8* %pi8, metadata !"bitset1")
; CHECK-NOT: llvm.bitset.test
@@ -105,15 +104,12 @@ define i1 @baz(i32* %p) {
; CHECK: [[T6:%[^ ]*]] = icmp ult i32 [[T5]], 66
; CHECK: br i1 [[T6]]
- ; CHECK: [[T8:%[^ ]*]] = lshr i32 [[T5]], 5
- ; CHECK: [[T9:%[^ ]*]] = getelementptr i32, i32* bitcast ([9 x i8]* @bitset3.bits to i32*), i32 [[T8]]
- ; CHECK: [[T10:%[^ ]*]] = load i32, i32* [[T9]]
- ; CHECK: [[T11:%[^ ]*]] = and i32 [[T5]], 31
- ; CHECK: [[T12:%[^ ]*]] = shl i32 1, [[T11]]
- ; CHECK: [[T13:%[^ ]*]] = and i32 [[T10]], [[T12]]
- ; CHECK: [[T14:%[^ ]*]] = icmp ne i32 [[T13]], 0
+ ; CHECK: [[T8:%[^ ]*]] = getelementptr i8, i8* @bits1, i32 [[T5]]
+ ; CHECK: [[T9:%[^ ]*]] = load i8, i8* [[T8]]
+ ; CHECK: [[T10:%[^ ]*]] = and i8 [[T9]], 2
+ ; CHECK: [[T11:%[^ ]*]] = icmp ne i8 [[T10]], 0
- ; CHECK: [[T16:%[^ ]*]] = phi i1 [ false, {{%[^ ]*}} ], [ [[T14]], {{%[^ ]*}} ]
+ ; CHECK: [[T16:%[^ ]*]] = phi i1 [ false, {{%[^ ]*}} ], [ [[T11]], {{%[^ ]*}} ]
%x = call i1 @llvm.bitset.test(i8* %pi8, metadata !"bitset3")
; CHECK: ret i1 [[T16]]
ret i1 %x
Modified: llvm/trunk/unittests/Transforms/IPO/LowerBitSets.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Transforms/IPO/LowerBitSets.cpp?rev=231043&r1=231042&r2=231043&view=diff
==============================================================================
--- llvm/trunk/unittests/Transforms/IPO/LowerBitSets.cpp (original)
+++ llvm/trunk/unittests/Transforms/IPO/LowerBitSets.cpp Mon Mar 2 18:49:28 2015
@@ -15,27 +15,39 @@ using namespace llvm;
TEST(LowerBitSets, BitSetBuilder) {
struct {
std::vector<uint64_t> Offsets;
- std::vector<uint8_t> Bits;
+ std::set<uint64_t> Bits;
uint64_t ByteOffset;
uint64_t BitSize;
unsigned AlignLog2;
bool IsSingleOffset;
bool IsAllOnes;
} BSBTests[] = {
- {{}, {0}, 0, 1, 0, false, false},
- {{0}, {1}, 0, 1, 0, true, true},
- {{4}, {1}, 4, 1, 0, true, true},
- {{37}, {1}, 37, 1, 0, true, true},
- {{0, 1}, {3}, 0, 2, 0, false, true},
- {{0, 4}, {3}, 0, 2, 2, false, true},
- {{0, uint64_t(1) << 33}, {3}, 0, 2, 33, false, true},
- {{3, 7}, {3}, 3, 2, 2, false, true},
- {{0, 1, 7}, {131}, 0, 8, 0, false, false},
- {{0, 2, 14}, {131}, 0, 8, 1, false, false},
- {{0, 1, 8}, {3, 1}, 0, 9, 0, false, false},
- {{0, 2, 16}, {3, 1}, 0, 9, 1, false, false},
- {{0, 1, 2, 3, 4, 5, 6, 7}, {255}, 0, 8, 0, false, true},
- {{0, 1, 2, 3, 4, 5, 6, 7, 8}, {255, 1}, 0, 9, 0, false, true},
+ {{}, {}, 0, 1, 0, false, false},
+ {{0}, {0}, 0, 1, 0, true, true},
+ {{4}, {0}, 4, 1, 0, true, true},
+ {{37}, {0}, 37, 1, 0, true, true},
+ {{0, 1}, {0, 1}, 0, 2, 0, false, true},
+ {{0, 4}, {0, 1}, 0, 2, 2, false, true},
+ {{0, uint64_t(1) << 33}, {0, 1}, 0, 2, 33, false, true},
+ {{3, 7}, {0, 1}, 3, 2, 2, false, true},
+ {{0, 1, 7}, {0, 1, 7}, 0, 8, 0, false, false},
+ {{0, 2, 14}, {0, 1, 7}, 0, 8, 1, false, false},
+ {{0, 1, 8}, {0, 1, 8}, 0, 9, 0, false, false},
+ {{0, 2, 16}, {0, 1, 8}, 0, 9, 1, false, false},
+ {{0, 1, 2, 3, 4, 5, 6, 7},
+ {0, 1, 2, 3, 4, 5, 6, 7},
+ 0,
+ 8,
+ 0,
+ false,
+ true},
+ {{0, 1, 2, 3, 4, 5, 6, 7, 8},
+ {0, 1, 2, 3, 4, 5, 6, 7, 8},
+ 0,
+ 9,
+ 0,
+ false,
+ true},
};
for (auto &&T : BSBTests) {
@@ -93,3 +105,51 @@ TEST(LowerBitSets, GlobalLayoutBuilder)
EXPECT_EQ(T.WantLayout, ComputedLayout);
}
}
+
+TEST(LowerBitSets, ByteArrayBuilder) {
+ struct BABAlloc {
+ std::set<uint64_t> Bits;
+ uint64_t BitSize;
+ uint64_t WantByteOffset;
+ uint8_t WantMask;
+ };
+
+ struct {
+ std::vector<BABAlloc> Allocs;
+ std::vector<uint8_t> WantBytes;
+ } BABTests[] = {
+ {{{{0}, 1, 0, 1}, {{0}, 1, 0, 2}}, {3}},
+ {{{{0}, 16, 0, 1},
+ {{1}, 15, 0, 2},
+ {{2}, 14, 0, 4},
+ {{3}, 13, 0, 8},
+ {{4}, 12, 0, 0x10},
+ {{5}, 11, 0, 0x20},
+ {{6}, 10, 0, 0x40},
+ {{7}, 9, 0, 0x80},
+ {{0}, 7, 9, 0x80},
+ {{0}, 6, 10, 0x40},
+ {{0}, 5, 11, 0x20},
+ {{0}, 4, 12, 0x10},
+ {{0}, 3, 13, 8},
+ {{0}, 2, 14, 4},
+ {{0}, 1, 15, 2}},
+ {1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80, 0, 0x80, 0x40, 0x20, 0x10, 8, 4,
+ 2}},
+ };
+
+ for (auto &&T : BABTests) {
+ ByteArrayBuilder BABuilder;
+
+ for (auto &&A : T.Allocs) {
+ uint64_t GotByteOffset;
+ uint8_t GotMask;
+
+ BABuilder.allocate(A.Bits, A.BitSize, GotByteOffset, GotMask);
+ EXPECT_EQ(A.WantByteOffset, GotByteOffset);
+ EXPECT_EQ(A.WantMask, GotMask);
+ }
+
+ EXPECT_EQ(T.WantBytes, BABuilder.Bytes);
+ }
+}
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