From 6d644ed39642012461fd6b727377d2d774662499 Mon Sep 17 00:00:00 2001 From: Guillaume Chatelet Date: Fri, 20 Sep 2019 13:40:31 +0000 Subject: [PATCH] [Alignment][NFC] migrate DataLayout internal struct to llvm::Align Summary: This is patch is part of a series to introduce an Alignment type. See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html See this patch for the introduction of the type: https://reviews.llvm.org/D64790 With this patch the PointerAlignElem struct goes from 20B to 16B. Reviewers: courbet Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D67400 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@372390 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/IR/DataLayout.h | 28 ++++++------ lib/IR/DataLayout.cpp | 106 +++++++++++++++++++++++-------------------- 2 files changed, 71 insertions(+), 63 deletions(-) diff --git a/include/llvm/IR/DataLayout.h b/include/llvm/IR/DataLayout.h index 918463d3987..7615832830a 100644 --- a/include/llvm/IR/DataLayout.h +++ b/include/llvm/IR/DataLayout.h @@ -72,11 +72,11 @@ struct LayoutAlignElem { /// Alignment type from \c AlignTypeEnum unsigned AlignType : 8; unsigned TypeBitWidth : 24; - unsigned ABIAlign : 16; - unsigned PrefAlign : 16; + llvm::Align ABIAlign; + llvm::Align PrefAlign; - static LayoutAlignElem get(AlignTypeEnum align_type, unsigned abi_align, - unsigned pref_align, uint32_t bit_width); + static LayoutAlignElem get(AlignTypeEnum align_type, llvm::Align abi_align, + llvm::Align pref_align, uint32_t bit_width); bool operator==(const LayoutAlignElem &rhs) const; }; @@ -88,15 +88,15 @@ struct LayoutAlignElem { /// \note The unusual order of elements in the structure attempts to reduce /// padding and make the structure slightly more cache friendly. struct PointerAlignElem { - unsigned ABIAlign; - unsigned PrefAlign; + llvm::Align ABIAlign; + llvm::Align PrefAlign; uint32_t TypeByteWidth; uint32_t AddressSpace; uint32_t IndexWidth; /// Initializer - static PointerAlignElem get(uint32_t AddressSpace, unsigned ABIAlign, - unsigned PrefAlign, uint32_t TypeByteWidth, + static PointerAlignElem get(uint32_t AddressSpace, llvm::Align ABIAlign, + llvm::Align PrefAlign, uint32_t TypeByteWidth, uint32_t IndexWidth); bool operator==(const PointerAlignElem &rhs) const; @@ -173,12 +173,12 @@ private: /// well-defined bitwise representation. SmallVector NonIntegralAddressSpaces; - void setAlignment(AlignTypeEnum align_type, unsigned abi_align, - unsigned pref_align, uint32_t bit_width); + void setAlignment(AlignTypeEnum align_type, llvm::Align abi_align, + llvm::Align pref_align, uint32_t bit_width); unsigned getAlignmentInfo(AlignTypeEnum align_type, uint32_t bit_width, bool ABIAlign, Type *Ty) const; - void setPointerAlignment(uint32_t AddrSpace, unsigned ABIAlign, - unsigned PrefAlign, uint32_t TypeByteWidth, + void setPointerAlignment(uint32_t AddrSpace, llvm::Align ABIAlign, + llvm::Align PrefAlign, uint32_t TypeByteWidth, uint32_t IndexWidth); /// Internal helper method that returns requested alignment for type. @@ -558,7 +558,7 @@ inline LLVMTargetDataRef wrap(const DataLayout *P) { /// based on the DataLayout structure. class StructLayout { uint64_t StructSize; - unsigned StructAlignment; + llvm::Align StructAlignment; unsigned IsPadded : 1; unsigned NumElements : 31; uint64_t MemberOffsets[1]; // variable sized array! @@ -568,7 +568,7 @@ public: uint64_t getSizeInBits() const { return 8 * StructSize; } - unsigned getAlignment() const { return StructAlignment; } + unsigned getAlignment() const { return StructAlignment.value(); } /// Returns whether the struct has padding or not between its fields. /// NB: Padding in nested element is not taken into account. diff --git a/lib/IR/DataLayout.cpp b/lib/IR/DataLayout.cpp index d56cd8ea5ab..0b59939f8c3 100644 --- a/lib/IR/DataLayout.cpp +++ b/lib/IR/DataLayout.cpp @@ -44,7 +44,6 @@ using namespace llvm; StructLayout::StructLayout(StructType *ST, const DataLayout &DL) { assert(!ST->isOpaque() && "Cannot get layout of opaque structs"); - StructAlignment = 0; StructSize = 0; IsPadded = false; NumElements = ST->getNumElements(); @@ -52,10 +51,10 @@ StructLayout::StructLayout(StructType *ST, const DataLayout &DL) { // Loop over each of the elements, placing them in memory. for (unsigned i = 0, e = NumElements; i != e; ++i) { Type *Ty = ST->getElementType(i); - unsigned TyAlign = ST->isPacked() ? 1 : DL.getABITypeAlignment(Ty); + const llvm::Align TyAlign(ST->isPacked() ? 1 : DL.getABITypeAlignment(Ty)); // Add padding if necessary to align the data element properly. - if ((StructSize & (TyAlign-1)) != 0) { + if (!isAligned(TyAlign, StructSize)) { IsPadded = true; StructSize = alignTo(StructSize, TyAlign); } @@ -67,12 +66,9 @@ StructLayout::StructLayout(StructType *ST, const DataLayout &DL) { StructSize += DL.getTypeAllocSize(Ty); // Consume space for this data item } - // Empty structures have alignment of 1 byte. - if (StructAlignment == 0) StructAlignment = 1; - // Add padding to the end of the struct so that it could be put in an array // and all array elements would be aligned correctly. - if ((StructSize & (StructAlignment-1)) != 0) { + if (!isAligned(StructAlignment, StructSize)) { IsPadded = true; StructSize = alignTo(StructSize, StructAlignment); } @@ -102,9 +98,10 @@ unsigned StructLayout::getElementContainingOffset(uint64_t Offset) const { // LayoutAlignElem, LayoutAlign support //===----------------------------------------------------------------------===// -LayoutAlignElem -LayoutAlignElem::get(AlignTypeEnum align_type, unsigned abi_align, - unsigned pref_align, uint32_t bit_width) { +LayoutAlignElem LayoutAlignElem::get(AlignTypeEnum align_type, + llvm::Align abi_align, + llvm::Align pref_align, + uint32_t bit_width) { assert(abi_align <= pref_align && "Preferred alignment worse than ABI!"); LayoutAlignElem retval; retval.AlignType = align_type; @@ -126,10 +123,11 @@ LayoutAlignElem::operator==(const LayoutAlignElem &rhs) const { // PointerAlignElem, PointerAlign support //===----------------------------------------------------------------------===// -PointerAlignElem -PointerAlignElem::get(uint32_t AddressSpace, unsigned ABIAlign, - unsigned PrefAlign, uint32_t TypeByteWidth, - uint32_t IndexWidth) { +PointerAlignElem PointerAlignElem::get(uint32_t AddressSpace, + llvm::Align ABIAlign, + llvm::Align PrefAlign, + uint32_t TypeByteWidth, + uint32_t IndexWidth) { assert(ABIAlign <= PrefAlign && "Preferred alignment worse than ABI!"); PointerAlignElem retval; retval.AddressSpace = AddressSpace; @@ -162,18 +160,19 @@ const char *DataLayout::getManglingComponent(const Triple &T) { } static const LayoutAlignElem DefaultAlignments[] = { - { INTEGER_ALIGN, 1, 1, 1 }, // i1 - { INTEGER_ALIGN, 8, 1, 1 }, // i8 - { INTEGER_ALIGN, 16, 2, 2 }, // i16 - { INTEGER_ALIGN, 32, 4, 4 }, // i32 - { INTEGER_ALIGN, 64, 4, 8 }, // i64 - { FLOAT_ALIGN, 16, 2, 2 }, // half - { FLOAT_ALIGN, 32, 4, 4 }, // float - { FLOAT_ALIGN, 64, 8, 8 }, // double - { FLOAT_ALIGN, 128, 16, 16 }, // ppcf128, quad, ... - { VECTOR_ALIGN, 64, 8, 8 }, // v2i32, v1i64, ... - { VECTOR_ALIGN, 128, 16, 16 }, // v16i8, v8i16, v4i32, ... - { AGGREGATE_ALIGN, 0, 0, 8 } // struct + {INTEGER_ALIGN, 1, llvm::Align(1), llvm::Align(1)}, // i1 + {INTEGER_ALIGN, 8, llvm::Align(1), llvm::Align(1)}, // i8 + {INTEGER_ALIGN, 16, llvm::Align(2), llvm::Align(2)}, // i16 + {INTEGER_ALIGN, 32, llvm::Align(4), llvm::Align(4)}, // i32 + {INTEGER_ALIGN, 64, llvm::Align(4), llvm::Align(8)}, // i64 + {FLOAT_ALIGN, 16, llvm::Align(2), llvm::Align(2)}, // half + {FLOAT_ALIGN, 32, llvm::Align(4), llvm::Align(4)}, // float + {FLOAT_ALIGN, 64, llvm::Align(8), llvm::Align(8)}, // double + {FLOAT_ALIGN, 128, llvm::Align(16), llvm::Align(16)}, // ppcf128, quad, ... + {VECTOR_ALIGN, 64, llvm::Align(8), llvm::Align(8)}, // v2i32, v1i64, ... + {VECTOR_ALIGN, 128, llvm::Align(16), + llvm::Align(16)}, // v16i8, v8i16, v4i32, ... + {AGGREGATE_ALIGN, 0, llvm::Align(1), llvm::Align(8)} // struct }; void DataLayout::reset(StringRef Desc) { @@ -194,7 +193,7 @@ void DataLayout::reset(StringRef Desc) { setAlignment((AlignTypeEnum)E.AlignType, E.ABIAlign, E.PrefAlign, E.TypeBitWidth); } - setPointerAlignment(0, 8, 8, 8, 8); + setPointerAlignment(0, llvm::Align(8), llvm::Align(8), 8, 8); parseSpecifier(Desc); } @@ -320,8 +319,9 @@ void DataLayout::parseSpecifier(StringRef Desc) { report_fatal_error("Invalid index size of 0 bytes"); } } - setPointerAlignment(AddrSpace, PointerABIAlign, PointerPrefAlign, - PointerMemSize, IndexSize); + setPointerAlignment(AddrSpace, assumeAligned(PointerABIAlign), + assumeAligned(PointerPrefAlign), PointerMemSize, + IndexSize); break; } case 'i': @@ -349,11 +349,16 @@ void DataLayout::parseSpecifier(StringRef Desc) { report_fatal_error( "Missing alignment specification in datalayout string"); Split = split(Rest, ':'); - unsigned ABIAlign = inBytes(getInt(Tok)); + const unsigned ABIAlign = inBytes(getInt(Tok)); if (AlignType != AGGREGATE_ALIGN && !ABIAlign) report_fatal_error( "ABI alignment specification must be >0 for non-aggregate types"); + if (!isUInt<16>(ABIAlign)) + report_fatal_error("Invalid ABI alignment, must be a 16bit integer"); + if (ABIAlign != 0 && !isPowerOf2_64(ABIAlign)) + report_fatal_error("Invalid ABI alignment, must be a power of 2"); + // Preferred alignment. unsigned PrefAlign = ABIAlign; if (!Rest.empty()) { @@ -361,7 +366,14 @@ void DataLayout::parseSpecifier(StringRef Desc) { PrefAlign = inBytes(getInt(Tok)); } - setAlignment(AlignType, ABIAlign, PrefAlign, Size); + if (!isUInt<16>(PrefAlign)) + report_fatal_error( + "Invalid preferred alignment, must be a 16bit integer"); + if (PrefAlign != 0 && !isPowerOf2_64(PrefAlign)) + report_fatal_error("Invalid preferred alignment, must be a power of 2"); + + setAlignment(AlignType, assumeAligned(ABIAlign), assumeAligned(PrefAlign), + Size); break; } @@ -474,20 +486,15 @@ DataLayout::findAlignmentLowerBound(AlignTypeEnum AlignType, }); } -void -DataLayout::setAlignment(AlignTypeEnum align_type, unsigned abi_align, - unsigned pref_align, uint32_t bit_width) { +void DataLayout::setAlignment(AlignTypeEnum align_type, llvm::Align abi_align, + llvm::Align pref_align, uint32_t bit_width) { + // AlignmentsTy::ABIAlign and AlignmentsTy::PrefAlign were once stored as + // uint16_t, it is unclear if there are requirements for alignment to be less + // than 2^16 other than storage. In the meantime we leave the restriction as + // an assert. See D67400 for context. + assert(Log2(abi_align) < 16 && Log2(pref_align) < 16 && "Alignment too big"); if (!isUInt<24>(bit_width)) report_fatal_error("Invalid bit width, must be a 24bit integer"); - if (!isUInt<16>(abi_align)) - report_fatal_error("Invalid ABI alignment, must be a 16bit integer"); - if (!isUInt<16>(pref_align)) - report_fatal_error("Invalid preferred alignment, must be a 16bit integer"); - if (abi_align != 0 && !isPowerOf2_64(abi_align)) - report_fatal_error("Invalid ABI alignment, must be a power of 2"); - if (pref_align != 0 && !isPowerOf2_64(pref_align)) - report_fatal_error("Invalid preferred alignment, must be a power of 2"); - if (pref_align < abi_align) report_fatal_error( "Preferred alignment cannot be less than the ABI alignment"); @@ -513,8 +520,9 @@ DataLayout::findPointerLowerBound(uint32_t AddressSpace) { }); } -void DataLayout::setPointerAlignment(uint32_t AddrSpace, unsigned ABIAlign, - unsigned PrefAlign, uint32_t TypeByteWidth, +void DataLayout::setPointerAlignment(uint32_t AddrSpace, llvm::Align ABIAlign, + llvm::Align PrefAlign, + uint32_t TypeByteWidth, uint32_t IndexWidth) { if (PrefAlign < ABIAlign) report_fatal_error( @@ -543,14 +551,14 @@ unsigned DataLayout::getAlignmentInfo(AlignTypeEnum AlignType, // the lower_bound will point to when it fails an exact match. if (I != Alignments.end() && I->AlignType == (unsigned)AlignType && (I->TypeBitWidth == BitWidth || AlignType == INTEGER_ALIGN)) - return ABIInfo ? I->ABIAlign : I->PrefAlign; + return (ABIInfo ? I->ABIAlign : I->PrefAlign).value(); if (AlignType == INTEGER_ALIGN) { // If we didn't have a larger value try the largest value we have. if (I != Alignments.begin()) { --I; // Go to the previous entry and see if its an integer. if (I->AlignType == INTEGER_ALIGN) - return ABIInfo ? I->ABIAlign : I->PrefAlign; + return (ABIInfo ? I->ABIAlign : I->PrefAlign).value(); } } else if (AlignType == VECTOR_ALIGN) { // By default, use natural alignment for vector types. This is consistent @@ -636,7 +644,7 @@ unsigned DataLayout::getPointerABIAlignment(unsigned AS) const { I = findPointerLowerBound(0); assert(I->AddressSpace == 0); } - return I->ABIAlign; + return I->ABIAlign.value(); } unsigned DataLayout::getPointerPrefAlignment(unsigned AS) const { @@ -645,7 +653,7 @@ unsigned DataLayout::getPointerPrefAlignment(unsigned AS) const { I = findPointerLowerBound(0); assert(I->AddressSpace == 0); } - return I->PrefAlign; + return I->PrefAlign.value(); } unsigned DataLayout::getPointerSize(unsigned AS) const { -- 2.11.4.GIT