2214 lines
81 KiB
C++
2214 lines
81 KiB
C++
//===-- ConstantFolding.cpp - Fold instructions into constants ------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines routines for folding instructions into constants.
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//
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// Also, to supplement the basic IR ConstantExpr simplifications,
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// this file defines some additional folding routines that can make use of
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// DataLayout information. These functions cannot go in IR due to library
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// dependency issues.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/ConstantFolding.h"
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#include "llvm/ADT/APFloat.h"
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#include "llvm/ADT/APInt.h"
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/Analysis/TargetLibraryInfo.h"
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#include "llvm/Analysis/ValueTracking.h"
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#include "llvm/Config/config.h"
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#include "llvm/IR/Constant.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/DerivedTypes.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/GlobalValue.h"
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#include "llvm/IR/GlobalVariable.h"
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#include "llvm/IR/InstrTypes.h"
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#include "llvm/IR/Instruction.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/Operator.h"
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#include "llvm/IR/Type.h"
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#include "llvm/IR/Value.h"
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#include "llvm/Support/Casting.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/KnownBits.h"
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#include "llvm/Support/MathExtras.h"
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#include <cassert>
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#include <cerrno>
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#include <cfenv>
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#include <cmath>
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#include <cstddef>
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#include <cstdint>
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using namespace llvm;
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namespace {
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//===----------------------------------------------------------------------===//
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// Constant Folding internal helper functions
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//===----------------------------------------------------------------------===//
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static Constant *foldConstVectorToAPInt(APInt &Result, Type *DestTy,
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Constant *C, Type *SrcEltTy,
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unsigned NumSrcElts,
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const DataLayout &DL) {
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// Now that we know that the input value is a vector of integers, just shift
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// and insert them into our result.
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unsigned BitShift = DL.getTypeSizeInBits(SrcEltTy);
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for (unsigned i = 0; i != NumSrcElts; ++i) {
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Constant *Element;
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if (DL.isLittleEndian())
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Element = C->getAggregateElement(NumSrcElts - i - 1);
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else
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Element = C->getAggregateElement(i);
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if (Element && isa<UndefValue>(Element)) {
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Result <<= BitShift;
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continue;
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}
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auto *ElementCI = dyn_cast_or_null<ConstantInt>(Element);
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if (!ElementCI)
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return ConstantExpr::getBitCast(C, DestTy);
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Result <<= BitShift;
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Result |= ElementCI->getValue().zextOrSelf(Result.getBitWidth());
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}
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return nullptr;
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}
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/// Constant fold bitcast, symbolically evaluating it with DataLayout.
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/// This always returns a non-null constant, but it may be a
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/// ConstantExpr if unfoldable.
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Constant *FoldBitCast(Constant *C, Type *DestTy, const DataLayout &DL) {
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// Catch the obvious splat cases.
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if (C->isNullValue() && !DestTy->isX86_MMXTy())
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return Constant::getNullValue(DestTy);
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if (C->isAllOnesValue() && !DestTy->isX86_MMXTy() &&
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!DestTy->isPtrOrPtrVectorTy()) // Don't get ones for ptr types!
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return Constant::getAllOnesValue(DestTy);
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if (auto *VTy = dyn_cast<VectorType>(C->getType())) {
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// Handle a vector->scalar integer/fp cast.
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if (isa<IntegerType>(DestTy) || DestTy->isFloatingPointTy()) {
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unsigned NumSrcElts = VTy->getNumElements();
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Type *SrcEltTy = VTy->getElementType();
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// If the vector is a vector of floating point, convert it to vector of int
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// to simplify things.
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if (SrcEltTy->isFloatingPointTy()) {
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unsigned FPWidth = SrcEltTy->getPrimitiveSizeInBits();
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Type *SrcIVTy =
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VectorType::get(IntegerType::get(C->getContext(), FPWidth), NumSrcElts);
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// Ask IR to do the conversion now that #elts line up.
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C = ConstantExpr::getBitCast(C, SrcIVTy);
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}
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APInt Result(DL.getTypeSizeInBits(DestTy), 0);
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if (Constant *CE = foldConstVectorToAPInt(Result, DestTy, C,
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SrcEltTy, NumSrcElts, DL))
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return CE;
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if (isa<IntegerType>(DestTy))
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return ConstantInt::get(DestTy, Result);
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APFloat FP(DestTy->getFltSemantics(), Result);
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return ConstantFP::get(DestTy->getContext(), FP);
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}
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}
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// The code below only handles casts to vectors currently.
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auto *DestVTy = dyn_cast<VectorType>(DestTy);
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if (!DestVTy)
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return ConstantExpr::getBitCast(C, DestTy);
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// If this is a scalar -> vector cast, convert the input into a <1 x scalar>
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// vector so the code below can handle it uniformly.
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if (isa<ConstantFP>(C) || isa<ConstantInt>(C)) {
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Constant *Ops = C; // don't take the address of C!
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return FoldBitCast(ConstantVector::get(Ops), DestTy, DL);
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}
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// If this is a bitcast from constant vector -> vector, fold it.
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if (!isa<ConstantDataVector>(C) && !isa<ConstantVector>(C))
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return ConstantExpr::getBitCast(C, DestTy);
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// If the element types match, IR can fold it.
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unsigned NumDstElt = DestVTy->getNumElements();
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unsigned NumSrcElt = C->getType()->getVectorNumElements();
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if (NumDstElt == NumSrcElt)
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return ConstantExpr::getBitCast(C, DestTy);
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Type *SrcEltTy = C->getType()->getVectorElementType();
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Type *DstEltTy = DestVTy->getElementType();
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// Otherwise, we're changing the number of elements in a vector, which
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// requires endianness information to do the right thing. For example,
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// bitcast (<2 x i64> <i64 0, i64 1> to <4 x i32>)
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// folds to (little endian):
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// <4 x i32> <i32 0, i32 0, i32 1, i32 0>
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// and to (big endian):
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// <4 x i32> <i32 0, i32 0, i32 0, i32 1>
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// First thing is first. We only want to think about integer here, so if
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// we have something in FP form, recast it as integer.
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if (DstEltTy->isFloatingPointTy()) {
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// Fold to an vector of integers with same size as our FP type.
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unsigned FPWidth = DstEltTy->getPrimitiveSizeInBits();
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Type *DestIVTy =
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VectorType::get(IntegerType::get(C->getContext(), FPWidth), NumDstElt);
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// Recursively handle this integer conversion, if possible.
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C = FoldBitCast(C, DestIVTy, DL);
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// Finally, IR can handle this now that #elts line up.
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return ConstantExpr::getBitCast(C, DestTy);
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}
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// Okay, we know the destination is integer, if the input is FP, convert
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// it to integer first.
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if (SrcEltTy->isFloatingPointTy()) {
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unsigned FPWidth = SrcEltTy->getPrimitiveSizeInBits();
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Type *SrcIVTy =
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VectorType::get(IntegerType::get(C->getContext(), FPWidth), NumSrcElt);
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// Ask IR to do the conversion now that #elts line up.
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C = ConstantExpr::getBitCast(C, SrcIVTy);
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// If IR wasn't able to fold it, bail out.
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if (!isa<ConstantVector>(C) && // FIXME: Remove ConstantVector.
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!isa<ConstantDataVector>(C))
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return C;
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}
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// Now we know that the input and output vectors are both integer vectors
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// of the same size, and that their #elements is not the same. Do the
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// conversion here, which depends on whether the input or output has
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// more elements.
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bool isLittleEndian = DL.isLittleEndian();
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SmallVector<Constant*, 32> Result;
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if (NumDstElt < NumSrcElt) {
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// Handle: bitcast (<4 x i32> <i32 0, i32 1, i32 2, i32 3> to <2 x i64>)
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Constant *Zero = Constant::getNullValue(DstEltTy);
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unsigned Ratio = NumSrcElt/NumDstElt;
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unsigned SrcBitSize = SrcEltTy->getPrimitiveSizeInBits();
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unsigned SrcElt = 0;
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for (unsigned i = 0; i != NumDstElt; ++i) {
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// Build each element of the result.
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Constant *Elt = Zero;
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unsigned ShiftAmt = isLittleEndian ? 0 : SrcBitSize*(Ratio-1);
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for (unsigned j = 0; j != Ratio; ++j) {
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Constant *Src = C->getAggregateElement(SrcElt++);
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if (Src && isa<UndefValue>(Src))
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Src = Constant::getNullValue(C->getType()->getVectorElementType());
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else
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Src = dyn_cast_or_null<ConstantInt>(Src);
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if (!Src) // Reject constantexpr elements.
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return ConstantExpr::getBitCast(C, DestTy);
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// Zero extend the element to the right size.
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Src = ConstantExpr::getZExt(Src, Elt->getType());
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// Shift it to the right place, depending on endianness.
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Src = ConstantExpr::getShl(Src,
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ConstantInt::get(Src->getType(), ShiftAmt));
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ShiftAmt += isLittleEndian ? SrcBitSize : -SrcBitSize;
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// Mix it in.
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Elt = ConstantExpr::getOr(Elt, Src);
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}
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Result.push_back(Elt);
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}
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return ConstantVector::get(Result);
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}
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// Handle: bitcast (<2 x i64> <i64 0, i64 1> to <4 x i32>)
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unsigned Ratio = NumDstElt/NumSrcElt;
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unsigned DstBitSize = DL.getTypeSizeInBits(DstEltTy);
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// Loop over each source value, expanding into multiple results.
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for (unsigned i = 0; i != NumSrcElt; ++i) {
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auto *Element = C->getAggregateElement(i);
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if (!Element) // Reject constantexpr elements.
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return ConstantExpr::getBitCast(C, DestTy);
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if (isa<UndefValue>(Element)) {
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// Correctly Propagate undef values.
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Result.append(Ratio, UndefValue::get(DstEltTy));
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continue;
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}
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auto *Src = dyn_cast<ConstantInt>(Element);
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if (!Src)
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return ConstantExpr::getBitCast(C, DestTy);
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unsigned ShiftAmt = isLittleEndian ? 0 : DstBitSize*(Ratio-1);
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for (unsigned j = 0; j != Ratio; ++j) {
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// Shift the piece of the value into the right place, depending on
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// endianness.
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Constant *Elt = ConstantExpr::getLShr(Src,
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ConstantInt::get(Src->getType(), ShiftAmt));
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ShiftAmt += isLittleEndian ? DstBitSize : -DstBitSize;
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// Truncate the element to an integer with the same pointer size and
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// convert the element back to a pointer using a inttoptr.
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if (DstEltTy->isPointerTy()) {
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IntegerType *DstIntTy = Type::getIntNTy(C->getContext(), DstBitSize);
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Constant *CE = ConstantExpr::getTrunc(Elt, DstIntTy);
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Result.push_back(ConstantExpr::getIntToPtr(CE, DstEltTy));
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continue;
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}
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// Truncate and remember this piece.
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Result.push_back(ConstantExpr::getTrunc(Elt, DstEltTy));
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}
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}
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return ConstantVector::get(Result);
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}
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} // end anonymous namespace
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/// If this constant is a constant offset from a global, return the global and
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/// the constant. Because of constantexprs, this function is recursive.
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bool llvm::IsConstantOffsetFromGlobal(Constant *C, GlobalValue *&GV,
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APInt &Offset, const DataLayout &DL) {
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// Trivial case, constant is the global.
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if ((GV = dyn_cast<GlobalValue>(C))) {
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unsigned BitWidth = DL.getPointerTypeSizeInBits(GV->getType());
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Offset = APInt(BitWidth, 0);
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return true;
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}
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// Otherwise, if this isn't a constant expr, bail out.
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auto *CE = dyn_cast<ConstantExpr>(C);
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if (!CE) return false;
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// Look through ptr->int and ptr->ptr casts.
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if (CE->getOpcode() == Instruction::PtrToInt ||
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CE->getOpcode() == Instruction::BitCast)
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return IsConstantOffsetFromGlobal(CE->getOperand(0), GV, Offset, DL);
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// i32* getelementptr ([5 x i32]* @a, i32 0, i32 5)
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auto *GEP = dyn_cast<GEPOperator>(CE);
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if (!GEP)
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return false;
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unsigned BitWidth = DL.getPointerTypeSizeInBits(GEP->getType());
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APInt TmpOffset(BitWidth, 0);
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// If the base isn't a global+constant, we aren't either.
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if (!IsConstantOffsetFromGlobal(CE->getOperand(0), GV, TmpOffset, DL))
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return false;
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// Otherwise, add any offset that our operands provide.
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if (!GEP->accumulateConstantOffset(DL, TmpOffset))
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return false;
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Offset = TmpOffset;
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return true;
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}
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namespace {
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/// Recursive helper to read bits out of global. C is the constant being copied
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/// out of. ByteOffset is an offset into C. CurPtr is the pointer to copy
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/// results into and BytesLeft is the number of bytes left in
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/// the CurPtr buffer. DL is the DataLayout.
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bool ReadDataFromGlobal(Constant *C, uint64_t ByteOffset, unsigned char *CurPtr,
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unsigned BytesLeft, const DataLayout &DL) {
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assert(ByteOffset <= DL.getTypeAllocSize(C->getType()) &&
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"Out of range access");
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// If this element is zero or undefined, we can just return since *CurPtr is
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// zero initialized.
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if (isa<ConstantAggregateZero>(C) || isa<UndefValue>(C))
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return true;
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if (auto *CI = dyn_cast<ConstantInt>(C)) {
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if (CI->getBitWidth() > 64 ||
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(CI->getBitWidth() & 7) != 0)
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return false;
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uint64_t Val = CI->getZExtValue();
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unsigned IntBytes = unsigned(CI->getBitWidth()/8);
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for (unsigned i = 0; i != BytesLeft && ByteOffset != IntBytes; ++i) {
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int n = ByteOffset;
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if (!DL.isLittleEndian())
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n = IntBytes - n - 1;
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CurPtr[i] = (unsigned char)(Val >> (n * 8));
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++ByteOffset;
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}
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return true;
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}
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if (auto *CFP = dyn_cast<ConstantFP>(C)) {
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if (CFP->getType()->isDoubleTy()) {
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C = FoldBitCast(C, Type::getInt64Ty(C->getContext()), DL);
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return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
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}
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if (CFP->getType()->isFloatTy()){
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C = FoldBitCast(C, Type::getInt32Ty(C->getContext()), DL);
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return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
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}
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if (CFP->getType()->isHalfTy()){
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C = FoldBitCast(C, Type::getInt16Ty(C->getContext()), DL);
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return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
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}
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return false;
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}
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if (auto *CS = dyn_cast<ConstantStruct>(C)) {
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const StructLayout *SL = DL.getStructLayout(CS->getType());
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unsigned Index = SL->getElementContainingOffset(ByteOffset);
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uint64_t CurEltOffset = SL->getElementOffset(Index);
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ByteOffset -= CurEltOffset;
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while (true) {
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// If the element access is to the element itself and not to tail padding,
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// read the bytes from the element.
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uint64_t EltSize = DL.getTypeAllocSize(CS->getOperand(Index)->getType());
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if (ByteOffset < EltSize &&
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!ReadDataFromGlobal(CS->getOperand(Index), ByteOffset, CurPtr,
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BytesLeft, DL))
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return false;
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++Index;
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// Check to see if we read from the last struct element, if so we're done.
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if (Index == CS->getType()->getNumElements())
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return true;
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// If we read all of the bytes we needed from this element we're done.
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uint64_t NextEltOffset = SL->getElementOffset(Index);
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if (BytesLeft <= NextEltOffset - CurEltOffset - ByteOffset)
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return true;
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// Move to the next element of the struct.
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CurPtr += NextEltOffset - CurEltOffset - ByteOffset;
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BytesLeft -= NextEltOffset - CurEltOffset - ByteOffset;
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ByteOffset = 0;
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CurEltOffset = NextEltOffset;
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}
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// not reached.
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}
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if (isa<ConstantArray>(C) || isa<ConstantVector>(C) ||
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isa<ConstantDataSequential>(C)) {
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Type *EltTy = C->getType()->getSequentialElementType();
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uint64_t EltSize = DL.getTypeAllocSize(EltTy);
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uint64_t Index = ByteOffset / EltSize;
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uint64_t Offset = ByteOffset - Index * EltSize;
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uint64_t NumElts;
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if (auto *AT = dyn_cast<ArrayType>(C->getType()))
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NumElts = AT->getNumElements();
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else
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NumElts = C->getType()->getVectorNumElements();
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for (; Index != NumElts; ++Index) {
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if (!ReadDataFromGlobal(C->getAggregateElement(Index), Offset, CurPtr,
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BytesLeft, DL))
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return false;
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uint64_t BytesWritten = EltSize - Offset;
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assert(BytesWritten <= EltSize && "Not indexing into this element?");
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if (BytesWritten >= BytesLeft)
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return true;
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Offset = 0;
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BytesLeft -= BytesWritten;
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CurPtr += BytesWritten;
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}
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return true;
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}
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if (auto *CE = dyn_cast<ConstantExpr>(C)) {
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if (CE->getOpcode() == Instruction::IntToPtr &&
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CE->getOperand(0)->getType() == DL.getIntPtrType(CE->getType())) {
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return ReadDataFromGlobal(CE->getOperand(0), ByteOffset, CurPtr,
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BytesLeft, DL);
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}
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}
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// Otherwise, unknown initializer type.
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return false;
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}
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Constant *FoldReinterpretLoadFromConstPtr(Constant *C, Type *LoadTy,
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const DataLayout &DL) {
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auto *PTy = cast<PointerType>(C->getType());
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auto *IntType = dyn_cast<IntegerType>(LoadTy);
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// If this isn't an integer load we can't fold it directly.
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if (!IntType) {
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unsigned AS = PTy->getAddressSpace();
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// If this is a float/double load, we can try folding it as an int32/64 load
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// and then bitcast the result. This can be useful for union cases. Note
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// that address spaces don't matter here since we're not going to result in
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// an actual new load.
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Type *MapTy;
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if (LoadTy->isHalfTy())
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MapTy = Type::getInt16Ty(C->getContext());
|
|
else if (LoadTy->isFloatTy())
|
|
MapTy = Type::getInt32Ty(C->getContext());
|
|
else if (LoadTy->isDoubleTy())
|
|
MapTy = Type::getInt64Ty(C->getContext());
|
|
else if (LoadTy->isVectorTy()) {
|
|
MapTy = PointerType::getIntNTy(C->getContext(),
|
|
DL.getTypeAllocSizeInBits(LoadTy));
|
|
} else
|
|
return nullptr;
|
|
|
|
C = FoldBitCast(C, MapTy->getPointerTo(AS), DL);
|
|
if (Constant *Res = FoldReinterpretLoadFromConstPtr(C, MapTy, DL))
|
|
return FoldBitCast(Res, LoadTy, DL);
|
|
return nullptr;
|
|
}
|
|
|
|
unsigned BytesLoaded = (IntType->getBitWidth() + 7) / 8;
|
|
if (BytesLoaded > 32 || BytesLoaded == 0)
|
|
return nullptr;
|
|
|
|
GlobalValue *GVal;
|
|
APInt OffsetAI;
|
|
if (!IsConstantOffsetFromGlobal(C, GVal, OffsetAI, DL))
|
|
return nullptr;
|
|
|
|
auto *GV = dyn_cast<GlobalVariable>(GVal);
|
|
if (!GV || !GV->isConstant() || !GV->hasDefinitiveInitializer() ||
|
|
!GV->getInitializer()->getType()->isSized())
|
|
return nullptr;
|
|
|
|
int64_t Offset = OffsetAI.getSExtValue();
|
|
int64_t InitializerSize = DL.getTypeAllocSize(GV->getInitializer()->getType());
|
|
|
|
// If we're not accessing anything in this constant, the result is undefined.
|
|
if (Offset + BytesLoaded <= 0)
|
|
return UndefValue::get(IntType);
|
|
|
|
// If we're not accessing anything in this constant, the result is undefined.
|
|
if (Offset >= InitializerSize)
|
|
return UndefValue::get(IntType);
|
|
|
|
unsigned char RawBytes[32] = {0};
|
|
unsigned char *CurPtr = RawBytes;
|
|
unsigned BytesLeft = BytesLoaded;
|
|
|
|
// If we're loading off the beginning of the global, some bytes may be valid.
|
|
if (Offset < 0) {
|
|
CurPtr += -Offset;
|
|
BytesLeft += Offset;
|
|
Offset = 0;
|
|
}
|
|
|
|
if (!ReadDataFromGlobal(GV->getInitializer(), Offset, CurPtr, BytesLeft, DL))
|
|
return nullptr;
|
|
|
|
APInt ResultVal = APInt(IntType->getBitWidth(), 0);
|
|
if (DL.isLittleEndian()) {
|
|
ResultVal = RawBytes[BytesLoaded - 1];
|
|
for (unsigned i = 1; i != BytesLoaded; ++i) {
|
|
ResultVal <<= 8;
|
|
ResultVal |= RawBytes[BytesLoaded - 1 - i];
|
|
}
|
|
} else {
|
|
ResultVal = RawBytes[0];
|
|
for (unsigned i = 1; i != BytesLoaded; ++i) {
|
|
ResultVal <<= 8;
|
|
ResultVal |= RawBytes[i];
|
|
}
|
|
}
|
|
|
|
return ConstantInt::get(IntType->getContext(), ResultVal);
|
|
}
|
|
|
|
Constant *ConstantFoldLoadThroughBitcast(ConstantExpr *CE, Type *DestTy,
|
|
const DataLayout &DL) {
|
|
auto *SrcPtr = CE->getOperand(0);
|
|
auto *SrcPtrTy = dyn_cast<PointerType>(SrcPtr->getType());
|
|
if (!SrcPtrTy)
|
|
return nullptr;
|
|
Type *SrcTy = SrcPtrTy->getPointerElementType();
|
|
|
|
Constant *C = ConstantFoldLoadFromConstPtr(SrcPtr, SrcTy, DL);
|
|
if (!C)
|
|
return nullptr;
|
|
|
|
do {
|
|
Type *SrcTy = C->getType();
|
|
|
|
// If the type sizes are the same and a cast is legal, just directly
|
|
// cast the constant.
|
|
if (DL.getTypeSizeInBits(DestTy) == DL.getTypeSizeInBits(SrcTy)) {
|
|
Instruction::CastOps Cast = Instruction::BitCast;
|
|
// If we are going from a pointer to int or vice versa, we spell the cast
|
|
// differently.
|
|
if (SrcTy->isIntegerTy() && DestTy->isPointerTy())
|
|
Cast = Instruction::IntToPtr;
|
|
else if (SrcTy->isPointerTy() && DestTy->isIntegerTy())
|
|
Cast = Instruction::PtrToInt;
|
|
|
|
if (CastInst::castIsValid(Cast, C, DestTy))
|
|
return ConstantExpr::getCast(Cast, C, DestTy);
|
|
}
|
|
|
|
// If this isn't an aggregate type, there is nothing we can do to drill down
|
|
// and find a bitcastable constant.
|
|
if (!SrcTy->isAggregateType())
|
|
return nullptr;
|
|
|
|
// We're simulating a load through a pointer that was bitcast to point to
|
|
// a different type, so we can try to walk down through the initial
|
|
// elements of an aggregate to see if some part of th e aggregate is
|
|
// castable to implement the "load" semantic model.
|
|
C = C->getAggregateElement(0u);
|
|
} while (C);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
} // end anonymous namespace
|
|
|
|
Constant *llvm::ConstantFoldLoadFromConstPtr(Constant *C, Type *Ty,
|
|
const DataLayout &DL) {
|
|
// First, try the easy cases:
|
|
if (auto *GV = dyn_cast<GlobalVariable>(C))
|
|
if (GV->isConstant() && GV->hasDefinitiveInitializer())
|
|
return GV->getInitializer();
|
|
|
|
if (auto *GA = dyn_cast<GlobalAlias>(C))
|
|
if (GA->getAliasee() && !GA->isInterposable())
|
|
return ConstantFoldLoadFromConstPtr(GA->getAliasee(), Ty, DL);
|
|
|
|
// If the loaded value isn't a constant expr, we can't handle it.
|
|
auto *CE = dyn_cast<ConstantExpr>(C);
|
|
if (!CE)
|
|
return nullptr;
|
|
|
|
if (CE->getOpcode() == Instruction::GetElementPtr) {
|
|
if (auto *GV = dyn_cast<GlobalVariable>(CE->getOperand(0))) {
|
|
if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
|
|
if (Constant *V =
|
|
ConstantFoldLoadThroughGEPConstantExpr(GV->getInitializer(), CE))
|
|
return V;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (CE->getOpcode() == Instruction::BitCast)
|
|
if (Constant *LoadedC = ConstantFoldLoadThroughBitcast(CE, Ty, DL))
|
|
return LoadedC;
|
|
|
|
// Instead of loading constant c string, use corresponding integer value
|
|
// directly if string length is small enough.
|
|
StringRef Str;
|
|
if (getConstantStringInfo(CE, Str) && !Str.empty()) {
|
|
size_t StrLen = Str.size();
|
|
unsigned NumBits = Ty->getPrimitiveSizeInBits();
|
|
// Replace load with immediate integer if the result is an integer or fp
|
|
// value.
|
|
if ((NumBits >> 3) == StrLen + 1 && (NumBits & 7) == 0 &&
|
|
(isa<IntegerType>(Ty) || Ty->isFloatingPointTy())) {
|
|
APInt StrVal(NumBits, 0);
|
|
APInt SingleChar(NumBits, 0);
|
|
if (DL.isLittleEndian()) {
|
|
for (unsigned char C : reverse(Str.bytes())) {
|
|
SingleChar = static_cast<uint64_t>(C);
|
|
StrVal = (StrVal << 8) | SingleChar;
|
|
}
|
|
} else {
|
|
for (unsigned char C : Str.bytes()) {
|
|
SingleChar = static_cast<uint64_t>(C);
|
|
StrVal = (StrVal << 8) | SingleChar;
|
|
}
|
|
// Append NULL at the end.
|
|
SingleChar = 0;
|
|
StrVal = (StrVal << 8) | SingleChar;
|
|
}
|
|
|
|
Constant *Res = ConstantInt::get(CE->getContext(), StrVal);
|
|
if (Ty->isFloatingPointTy())
|
|
Res = ConstantExpr::getBitCast(Res, Ty);
|
|
return Res;
|
|
}
|
|
}
|
|
|
|
// If this load comes from anywhere in a constant global, and if the global
|
|
// is all undef or zero, we know what it loads.
|
|
if (auto *GV = dyn_cast<GlobalVariable>(GetUnderlyingObject(CE, DL))) {
|
|
if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
|
|
if (GV->getInitializer()->isNullValue())
|
|
return Constant::getNullValue(Ty);
|
|
if (isa<UndefValue>(GV->getInitializer()))
|
|
return UndefValue::get(Ty);
|
|
}
|
|
}
|
|
|
|
// Try hard to fold loads from bitcasted strange and non-type-safe things.
|
|
return FoldReinterpretLoadFromConstPtr(CE, Ty, DL);
|
|
}
|
|
|
|
namespace {
|
|
|
|
Constant *ConstantFoldLoadInst(const LoadInst *LI, const DataLayout &DL) {
|
|
if (LI->isVolatile()) return nullptr;
|
|
|
|
if (auto *C = dyn_cast<Constant>(LI->getOperand(0)))
|
|
return ConstantFoldLoadFromConstPtr(C, LI->getType(), DL);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// One of Op0/Op1 is a constant expression.
|
|
/// Attempt to symbolically evaluate the result of a binary operator merging
|
|
/// these together. If target data info is available, it is provided as DL,
|
|
/// otherwise DL is null.
|
|
Constant *SymbolicallyEvaluateBinop(unsigned Opc, Constant *Op0, Constant *Op1,
|
|
const DataLayout &DL) {
|
|
// SROA
|
|
|
|
// Fold (and 0xffffffff00000000, (shl x, 32)) -> shl.
|
|
// Fold (lshr (or X, Y), 32) -> (lshr [X/Y], 32) if one doesn't contribute
|
|
// bits.
|
|
|
|
if (Opc == Instruction::And) {
|
|
unsigned BitWidth = DL.getTypeSizeInBits(Op0->getType()->getScalarType());
|
|
KnownBits Known0(BitWidth);
|
|
KnownBits Known1(BitWidth);
|
|
computeKnownBits(Op0, Known0, DL);
|
|
computeKnownBits(Op1, Known1, DL);
|
|
if ((Known1.One | Known0.Zero).isAllOnesValue()) {
|
|
// All the bits of Op0 that the 'and' could be masking are already zero.
|
|
return Op0;
|
|
}
|
|
if ((Known0.One | Known1.Zero).isAllOnesValue()) {
|
|
// All the bits of Op1 that the 'and' could be masking are already zero.
|
|
return Op1;
|
|
}
|
|
|
|
Known0.Zero |= Known1.Zero;
|
|
Known0.One &= Known1.One;
|
|
if (Known0.isConstant())
|
|
return ConstantInt::get(Op0->getType(), Known0.getConstant());
|
|
}
|
|
|
|
// If the constant expr is something like &A[123] - &A[4].f, fold this into a
|
|
// constant. This happens frequently when iterating over a global array.
|
|
if (Opc == Instruction::Sub) {
|
|
GlobalValue *GV1, *GV2;
|
|
APInt Offs1, Offs2;
|
|
|
|
if (IsConstantOffsetFromGlobal(Op0, GV1, Offs1, DL))
|
|
if (IsConstantOffsetFromGlobal(Op1, GV2, Offs2, DL) && GV1 == GV2) {
|
|
unsigned OpSize = DL.getTypeSizeInBits(Op0->getType());
|
|
|
|
// (&GV+C1) - (&GV+C2) -> C1-C2, pointer arithmetic cannot overflow.
|
|
// PtrToInt may change the bitwidth so we have convert to the right size
|
|
// first.
|
|
return ConstantInt::get(Op0->getType(), Offs1.zextOrTrunc(OpSize) -
|
|
Offs2.zextOrTrunc(OpSize));
|
|
}
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// If array indices are not pointer-sized integers, explicitly cast them so
|
|
/// that they aren't implicitly casted by the getelementptr.
|
|
Constant *CastGEPIndices(Type *SrcElemTy, ArrayRef<Constant *> Ops,
|
|
Type *ResultTy, Optional<unsigned> InRangeIndex,
|
|
const DataLayout &DL, const TargetLibraryInfo *TLI) {
|
|
Type *IntPtrTy = DL.getIntPtrType(ResultTy);
|
|
Type *IntPtrScalarTy = IntPtrTy->getScalarType();
|
|
|
|
bool Any = false;
|
|
SmallVector<Constant*, 32> NewIdxs;
|
|
for (unsigned i = 1, e = Ops.size(); i != e; ++i) {
|
|
if ((i == 1 ||
|
|
!isa<StructType>(GetElementPtrInst::getIndexedType(
|
|
SrcElemTy, Ops.slice(1, i - 1)))) &&
|
|
Ops[i]->getType()->getScalarType() != IntPtrScalarTy) {
|
|
Any = true;
|
|
Type *NewType = Ops[i]->getType()->isVectorTy()
|
|
? IntPtrTy
|
|
: IntPtrTy->getScalarType();
|
|
NewIdxs.push_back(ConstantExpr::getCast(CastInst::getCastOpcode(Ops[i],
|
|
true,
|
|
NewType,
|
|
true),
|
|
Ops[i], NewType));
|
|
} else
|
|
NewIdxs.push_back(Ops[i]);
|
|
}
|
|
|
|
if (!Any)
|
|
return nullptr;
|
|
|
|
Constant *C = ConstantExpr::getGetElementPtr(
|
|
SrcElemTy, Ops[0], NewIdxs, /*InBounds=*/false, InRangeIndex);
|
|
if (Constant *Folded = ConstantFoldConstant(C, DL, TLI))
|
|
C = Folded;
|
|
|
|
return C;
|
|
}
|
|
|
|
/// Strip the pointer casts, but preserve the address space information.
|
|
Constant* StripPtrCastKeepAS(Constant* Ptr, Type *&ElemTy) {
|
|
assert(Ptr->getType()->isPointerTy() && "Not a pointer type");
|
|
auto *OldPtrTy = cast<PointerType>(Ptr->getType());
|
|
Ptr = Ptr->stripPointerCasts();
|
|
auto *NewPtrTy = cast<PointerType>(Ptr->getType());
|
|
|
|
ElemTy = NewPtrTy->getPointerElementType();
|
|
|
|
// Preserve the address space number of the pointer.
|
|
if (NewPtrTy->getAddressSpace() != OldPtrTy->getAddressSpace()) {
|
|
NewPtrTy = ElemTy->getPointerTo(OldPtrTy->getAddressSpace());
|
|
Ptr = ConstantExpr::getPointerCast(Ptr, NewPtrTy);
|
|
}
|
|
return Ptr;
|
|
}
|
|
|
|
/// If we can symbolically evaluate the GEP constant expression, do so.
|
|
Constant *SymbolicallyEvaluateGEP(const GEPOperator *GEP,
|
|
ArrayRef<Constant *> Ops,
|
|
const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
const GEPOperator *InnermostGEP = GEP;
|
|
bool InBounds = GEP->isInBounds();
|
|
|
|
Type *SrcElemTy = GEP->getSourceElementType();
|
|
Type *ResElemTy = GEP->getResultElementType();
|
|
Type *ResTy = GEP->getType();
|
|
if (!SrcElemTy->isSized())
|
|
return nullptr;
|
|
|
|
if (Constant *C = CastGEPIndices(SrcElemTy, Ops, ResTy,
|
|
GEP->getInRangeIndex(), DL, TLI))
|
|
return C;
|
|
|
|
Constant *Ptr = Ops[0];
|
|
if (!Ptr->getType()->isPointerTy())
|
|
return nullptr;
|
|
|
|
Type *IntPtrTy = DL.getIntPtrType(Ptr->getType());
|
|
|
|
// If this is a constant expr gep that is effectively computing an
|
|
// "offsetof", fold it into 'cast int Size to T*' instead of 'gep 0, 0, 12'
|
|
for (unsigned i = 1, e = Ops.size(); i != e; ++i)
|
|
if (!isa<ConstantInt>(Ops[i])) {
|
|
|
|
// If this is "gep i8* Ptr, (sub 0, V)", fold this as:
|
|
// "inttoptr (sub (ptrtoint Ptr), V)"
|
|
if (Ops.size() == 2 && ResElemTy->isIntegerTy(8)) {
|
|
auto *CE = dyn_cast<ConstantExpr>(Ops[1]);
|
|
assert((!CE || CE->getType() == IntPtrTy) &&
|
|
"CastGEPIndices didn't canonicalize index types!");
|
|
if (CE && CE->getOpcode() == Instruction::Sub &&
|
|
CE->getOperand(0)->isNullValue()) {
|
|
Constant *Res = ConstantExpr::getPtrToInt(Ptr, CE->getType());
|
|
Res = ConstantExpr::getSub(Res, CE->getOperand(1));
|
|
Res = ConstantExpr::getIntToPtr(Res, ResTy);
|
|
if (auto *FoldedRes = ConstantFoldConstant(Res, DL, TLI))
|
|
Res = FoldedRes;
|
|
return Res;
|
|
}
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
unsigned BitWidth = DL.getTypeSizeInBits(IntPtrTy);
|
|
APInt Offset =
|
|
APInt(BitWidth,
|
|
DL.getIndexedOffsetInType(
|
|
SrcElemTy,
|
|
makeArrayRef((Value * const *)Ops.data() + 1, Ops.size() - 1)));
|
|
Ptr = StripPtrCastKeepAS(Ptr, SrcElemTy);
|
|
|
|
// If this is a GEP of a GEP, fold it all into a single GEP.
|
|
while (auto *GEP = dyn_cast<GEPOperator>(Ptr)) {
|
|
InnermostGEP = GEP;
|
|
InBounds &= GEP->isInBounds();
|
|
|
|
SmallVector<Value *, 4> NestedOps(GEP->op_begin() + 1, GEP->op_end());
|
|
|
|
// Do not try the incorporate the sub-GEP if some index is not a number.
|
|
bool AllConstantInt = true;
|
|
for (Value *NestedOp : NestedOps)
|
|
if (!isa<ConstantInt>(NestedOp)) {
|
|
AllConstantInt = false;
|
|
break;
|
|
}
|
|
if (!AllConstantInt)
|
|
break;
|
|
|
|
Ptr = cast<Constant>(GEP->getOperand(0));
|
|
SrcElemTy = GEP->getSourceElementType();
|
|
Offset += APInt(BitWidth, DL.getIndexedOffsetInType(SrcElemTy, NestedOps));
|
|
Ptr = StripPtrCastKeepAS(Ptr, SrcElemTy);
|
|
}
|
|
|
|
// If the base value for this address is a literal integer value, fold the
|
|
// getelementptr to the resulting integer value casted to the pointer type.
|
|
APInt BasePtr(BitWidth, 0);
|
|
if (auto *CE = dyn_cast<ConstantExpr>(Ptr)) {
|
|
if (CE->getOpcode() == Instruction::IntToPtr) {
|
|
if (auto *Base = dyn_cast<ConstantInt>(CE->getOperand(0)))
|
|
BasePtr = Base->getValue().zextOrTrunc(BitWidth);
|
|
}
|
|
}
|
|
|
|
auto *PTy = cast<PointerType>(Ptr->getType());
|
|
if ((Ptr->isNullValue() || BasePtr != 0) &&
|
|
!DL.isNonIntegralPointerType(PTy)) {
|
|
Constant *C = ConstantInt::get(Ptr->getContext(), Offset + BasePtr);
|
|
return ConstantExpr::getIntToPtr(C, ResTy);
|
|
}
|
|
|
|
// Otherwise form a regular getelementptr. Recompute the indices so that
|
|
// we eliminate over-indexing of the notional static type array bounds.
|
|
// This makes it easy to determine if the getelementptr is "inbounds".
|
|
// Also, this helps GlobalOpt do SROA on GlobalVariables.
|
|
Type *Ty = PTy;
|
|
SmallVector<Constant *, 32> NewIdxs;
|
|
|
|
do {
|
|
if (!Ty->isStructTy()) {
|
|
if (Ty->isPointerTy()) {
|
|
// The only pointer indexing we'll do is on the first index of the GEP.
|
|
if (!NewIdxs.empty())
|
|
break;
|
|
|
|
Ty = SrcElemTy;
|
|
|
|
// Only handle pointers to sized types, not pointers to functions.
|
|
if (!Ty->isSized())
|
|
return nullptr;
|
|
} else if (auto *ATy = dyn_cast<SequentialType>(Ty)) {
|
|
Ty = ATy->getElementType();
|
|
} else {
|
|
// We've reached some non-indexable type.
|
|
break;
|
|
}
|
|
|
|
// Determine which element of the array the offset points into.
|
|
APInt ElemSize(BitWidth, DL.getTypeAllocSize(Ty));
|
|
if (ElemSize == 0) {
|
|
// The element size is 0. This may be [0 x Ty]*, so just use a zero
|
|
// index for this level and proceed to the next level to see if it can
|
|
// accommodate the offset.
|
|
NewIdxs.push_back(ConstantInt::get(IntPtrTy, 0));
|
|
} else {
|
|
// The element size is non-zero divide the offset by the element
|
|
// size (rounding down), to compute the index at this level.
|
|
bool Overflow;
|
|
APInt NewIdx = Offset.sdiv_ov(ElemSize, Overflow);
|
|
if (Overflow)
|
|
break;
|
|
Offset -= NewIdx * ElemSize;
|
|
NewIdxs.push_back(ConstantInt::get(IntPtrTy, NewIdx));
|
|
}
|
|
} else {
|
|
auto *STy = cast<StructType>(Ty);
|
|
// If we end up with an offset that isn't valid for this struct type, we
|
|
// can't re-form this GEP in a regular form, so bail out. The pointer
|
|
// operand likely went through casts that are necessary to make the GEP
|
|
// sensible.
|
|
const StructLayout &SL = *DL.getStructLayout(STy);
|
|
if (Offset.isNegative() || Offset.uge(SL.getSizeInBytes()))
|
|
break;
|
|
|
|
// Determine which field of the struct the offset points into. The
|
|
// getZExtValue is fine as we've already ensured that the offset is
|
|
// within the range representable by the StructLayout API.
|
|
unsigned ElIdx = SL.getElementContainingOffset(Offset.getZExtValue());
|
|
NewIdxs.push_back(ConstantInt::get(Type::getInt32Ty(Ty->getContext()),
|
|
ElIdx));
|
|
Offset -= APInt(BitWidth, SL.getElementOffset(ElIdx));
|
|
Ty = STy->getTypeAtIndex(ElIdx);
|
|
}
|
|
} while (Ty != ResElemTy);
|
|
|
|
// If we haven't used up the entire offset by descending the static
|
|
// type, then the offset is pointing into the middle of an indivisible
|
|
// member, so we can't simplify it.
|
|
if (Offset != 0)
|
|
return nullptr;
|
|
|
|
// Preserve the inrange index from the innermost GEP if possible. We must
|
|
// have calculated the same indices up to and including the inrange index.
|
|
Optional<unsigned> InRangeIndex;
|
|
if (Optional<unsigned> LastIRIndex = InnermostGEP->getInRangeIndex())
|
|
if (SrcElemTy == InnermostGEP->getSourceElementType() &&
|
|
NewIdxs.size() > *LastIRIndex) {
|
|
InRangeIndex = LastIRIndex;
|
|
for (unsigned I = 0; I <= *LastIRIndex; ++I)
|
|
if (NewIdxs[I] != InnermostGEP->getOperand(I + 1)) {
|
|
InRangeIndex = None;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Create a GEP.
|
|
Constant *C = ConstantExpr::getGetElementPtr(SrcElemTy, Ptr, NewIdxs,
|
|
InBounds, InRangeIndex);
|
|
assert(C->getType()->getPointerElementType() == Ty &&
|
|
"Computed GetElementPtr has unexpected type!");
|
|
|
|
// If we ended up indexing a member with a type that doesn't match
|
|
// the type of what the original indices indexed, add a cast.
|
|
if (Ty != ResElemTy)
|
|
C = FoldBitCast(C, ResTy, DL);
|
|
|
|
return C;
|
|
}
|
|
|
|
/// Attempt to constant fold an instruction with the
|
|
/// specified opcode and operands. If successful, the constant result is
|
|
/// returned, if not, null is returned. Note that this function can fail when
|
|
/// attempting to fold instructions like loads and stores, which have no
|
|
/// constant expression form.
|
|
///
|
|
/// TODO: This function neither utilizes nor preserves nsw/nuw/inbounds/inrange
|
|
/// etc information, due to only being passed an opcode and operands. Constant
|
|
/// folding using this function strips this information.
|
|
///
|
|
Constant *ConstantFoldInstOperandsImpl(const Value *InstOrCE, unsigned Opcode,
|
|
ArrayRef<Constant *> Ops,
|
|
const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
Type *DestTy = InstOrCE->getType();
|
|
|
|
// Handle easy binops first.
|
|
if (Instruction::isBinaryOp(Opcode))
|
|
return ConstantFoldBinaryOpOperands(Opcode, Ops[0], Ops[1], DL);
|
|
|
|
if (Instruction::isCast(Opcode))
|
|
return ConstantFoldCastOperand(Opcode, Ops[0], DestTy, DL);
|
|
|
|
if (auto *GEP = dyn_cast<GEPOperator>(InstOrCE)) {
|
|
if (Constant *C = SymbolicallyEvaluateGEP(GEP, Ops, DL, TLI))
|
|
return C;
|
|
|
|
return ConstantExpr::getGetElementPtr(GEP->getSourceElementType(), Ops[0],
|
|
Ops.slice(1), GEP->isInBounds(),
|
|
GEP->getInRangeIndex());
|
|
}
|
|
|
|
if (auto *CE = dyn_cast<ConstantExpr>(InstOrCE))
|
|
return CE->getWithOperands(Ops);
|
|
|
|
switch (Opcode) {
|
|
default: return nullptr;
|
|
case Instruction::ICmp:
|
|
case Instruction::FCmp: llvm_unreachable("Invalid for compares");
|
|
case Instruction::Call:
|
|
if (auto *F = dyn_cast<Function>(Ops.back()))
|
|
if (canConstantFoldCallTo(F))
|
|
return ConstantFoldCall(F, Ops.slice(0, Ops.size() - 1), TLI);
|
|
return nullptr;
|
|
case Instruction::Select:
|
|
return ConstantExpr::getSelect(Ops[0], Ops[1], Ops[2]);
|
|
case Instruction::ExtractElement:
|
|
return ConstantExpr::getExtractElement(Ops[0], Ops[1]);
|
|
case Instruction::InsertElement:
|
|
return ConstantExpr::getInsertElement(Ops[0], Ops[1], Ops[2]);
|
|
case Instruction::ShuffleVector:
|
|
return ConstantExpr::getShuffleVector(Ops[0], Ops[1], Ops[2]);
|
|
}
|
|
}
|
|
|
|
} // end anonymous namespace
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Constant Folding public APIs
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
|
|
Constant *
|
|
ConstantFoldConstantImpl(const Constant *C, const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI,
|
|
SmallDenseMap<Constant *, Constant *> &FoldedOps) {
|
|
if (!isa<ConstantVector>(C) && !isa<ConstantExpr>(C))
|
|
return nullptr;
|
|
|
|
SmallVector<Constant *, 8> Ops;
|
|
for (const Use &NewU : C->operands()) {
|
|
auto *NewC = cast<Constant>(&NewU);
|
|
// Recursively fold the ConstantExpr's operands. If we have already folded
|
|
// a ConstantExpr, we don't have to process it again.
|
|
if (isa<ConstantVector>(NewC) || isa<ConstantExpr>(NewC)) {
|
|
auto It = FoldedOps.find(NewC);
|
|
if (It == FoldedOps.end()) {
|
|
if (auto *FoldedC =
|
|
ConstantFoldConstantImpl(NewC, DL, TLI, FoldedOps)) {
|
|
FoldedOps.insert({NewC, FoldedC});
|
|
NewC = FoldedC;
|
|
} else {
|
|
FoldedOps.insert({NewC, NewC});
|
|
}
|
|
} else {
|
|
NewC = It->second;
|
|
}
|
|
}
|
|
Ops.push_back(NewC);
|
|
}
|
|
|
|
if (auto *CE = dyn_cast<ConstantExpr>(C)) {
|
|
if (CE->isCompare())
|
|
return ConstantFoldCompareInstOperands(CE->getPredicate(), Ops[0], Ops[1],
|
|
DL, TLI);
|
|
|
|
return ConstantFoldInstOperandsImpl(CE, CE->getOpcode(), Ops, DL, TLI);
|
|
}
|
|
|
|
assert(isa<ConstantVector>(C));
|
|
return ConstantVector::get(Ops);
|
|
}
|
|
|
|
} // end anonymous namespace
|
|
|
|
Constant *llvm::ConstantFoldInstruction(Instruction *I, const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
// Handle PHI nodes quickly here...
|
|
if (auto *PN = dyn_cast<PHINode>(I)) {
|
|
Constant *CommonValue = nullptr;
|
|
|
|
SmallDenseMap<Constant *, Constant *> FoldedOps;
|
|
for (Value *Incoming : PN->incoming_values()) {
|
|
// If the incoming value is undef then skip it. Note that while we could
|
|
// skip the value if it is equal to the phi node itself we choose not to
|
|
// because that would break the rule that constant folding only applies if
|
|
// all operands are constants.
|
|
if (isa<UndefValue>(Incoming))
|
|
continue;
|
|
// If the incoming value is not a constant, then give up.
|
|
auto *C = dyn_cast<Constant>(Incoming);
|
|
if (!C)
|
|
return nullptr;
|
|
// Fold the PHI's operands.
|
|
if (auto *FoldedC = ConstantFoldConstantImpl(C, DL, TLI, FoldedOps))
|
|
C = FoldedC;
|
|
// If the incoming value is a different constant to
|
|
// the one we saw previously, then give up.
|
|
if (CommonValue && C != CommonValue)
|
|
return nullptr;
|
|
CommonValue = C;
|
|
}
|
|
|
|
// If we reach here, all incoming values are the same constant or undef.
|
|
return CommonValue ? CommonValue : UndefValue::get(PN->getType());
|
|
}
|
|
|
|
// Scan the operand list, checking to see if they are all constants, if so,
|
|
// hand off to ConstantFoldInstOperandsImpl.
|
|
if (!all_of(I->operands(), [](Use &U) { return isa<Constant>(U); }))
|
|
return nullptr;
|
|
|
|
SmallDenseMap<Constant *, Constant *> FoldedOps;
|
|
SmallVector<Constant *, 8> Ops;
|
|
for (const Use &OpU : I->operands()) {
|
|
auto *Op = cast<Constant>(&OpU);
|
|
// Fold the Instruction's operands.
|
|
if (auto *FoldedOp = ConstantFoldConstantImpl(Op, DL, TLI, FoldedOps))
|
|
Op = FoldedOp;
|
|
|
|
Ops.push_back(Op);
|
|
}
|
|
|
|
if (const auto *CI = dyn_cast<CmpInst>(I))
|
|
return ConstantFoldCompareInstOperands(CI->getPredicate(), Ops[0], Ops[1],
|
|
DL, TLI);
|
|
|
|
if (const auto *LI = dyn_cast<LoadInst>(I))
|
|
return ConstantFoldLoadInst(LI, DL);
|
|
|
|
if (auto *IVI = dyn_cast<InsertValueInst>(I)) {
|
|
return ConstantExpr::getInsertValue(
|
|
cast<Constant>(IVI->getAggregateOperand()),
|
|
cast<Constant>(IVI->getInsertedValueOperand()),
|
|
IVI->getIndices());
|
|
}
|
|
|
|
if (auto *EVI = dyn_cast<ExtractValueInst>(I)) {
|
|
return ConstantExpr::getExtractValue(
|
|
cast<Constant>(EVI->getAggregateOperand()),
|
|
EVI->getIndices());
|
|
}
|
|
|
|
return ConstantFoldInstOperands(I, Ops, DL, TLI);
|
|
}
|
|
|
|
Constant *llvm::ConstantFoldConstant(const Constant *C, const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
SmallDenseMap<Constant *, Constant *> FoldedOps;
|
|
return ConstantFoldConstantImpl(C, DL, TLI, FoldedOps);
|
|
}
|
|
|
|
Constant *llvm::ConstantFoldInstOperands(Instruction *I,
|
|
ArrayRef<Constant *> Ops,
|
|
const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
return ConstantFoldInstOperandsImpl(I, I->getOpcode(), Ops, DL, TLI);
|
|
}
|
|
|
|
Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
|
|
Constant *Ops0, Constant *Ops1,
|
|
const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
// fold: icmp (inttoptr x), null -> icmp x, 0
|
|
// fold: icmp (ptrtoint x), 0 -> icmp x, null
|
|
// fold: icmp (inttoptr x), (inttoptr y) -> icmp trunc/zext x, trunc/zext y
|
|
// fold: icmp (ptrtoint x), (ptrtoint y) -> icmp x, y
|
|
//
|
|
// FIXME: The following comment is out of data and the DataLayout is here now.
|
|
// ConstantExpr::getCompare cannot do this, because it doesn't have DL
|
|
// around to know if bit truncation is happening.
|
|
if (auto *CE0 = dyn_cast<ConstantExpr>(Ops0)) {
|
|
if (Ops1->isNullValue()) {
|
|
if (CE0->getOpcode() == Instruction::IntToPtr) {
|
|
Type *IntPtrTy = DL.getIntPtrType(CE0->getType());
|
|
// Convert the integer value to the right size to ensure we get the
|
|
// proper extension or truncation.
|
|
Constant *C = ConstantExpr::getIntegerCast(CE0->getOperand(0),
|
|
IntPtrTy, false);
|
|
Constant *Null = Constant::getNullValue(C->getType());
|
|
return ConstantFoldCompareInstOperands(Predicate, C, Null, DL, TLI);
|
|
}
|
|
|
|
// Only do this transformation if the int is intptrty in size, otherwise
|
|
// there is a truncation or extension that we aren't modeling.
|
|
if (CE0->getOpcode() == Instruction::PtrToInt) {
|
|
Type *IntPtrTy = DL.getIntPtrType(CE0->getOperand(0)->getType());
|
|
if (CE0->getType() == IntPtrTy) {
|
|
Constant *C = CE0->getOperand(0);
|
|
Constant *Null = Constant::getNullValue(C->getType());
|
|
return ConstantFoldCompareInstOperands(Predicate, C, Null, DL, TLI);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (auto *CE1 = dyn_cast<ConstantExpr>(Ops1)) {
|
|
if (CE0->getOpcode() == CE1->getOpcode()) {
|
|
if (CE0->getOpcode() == Instruction::IntToPtr) {
|
|
Type *IntPtrTy = DL.getIntPtrType(CE0->getType());
|
|
|
|
// Convert the integer value to the right size to ensure we get the
|
|
// proper extension or truncation.
|
|
Constant *C0 = ConstantExpr::getIntegerCast(CE0->getOperand(0),
|
|
IntPtrTy, false);
|
|
Constant *C1 = ConstantExpr::getIntegerCast(CE1->getOperand(0),
|
|
IntPtrTy, false);
|
|
return ConstantFoldCompareInstOperands(Predicate, C0, C1, DL, TLI);
|
|
}
|
|
|
|
// Only do this transformation if the int is intptrty in size, otherwise
|
|
// there is a truncation or extension that we aren't modeling.
|
|
if (CE0->getOpcode() == Instruction::PtrToInt) {
|
|
Type *IntPtrTy = DL.getIntPtrType(CE0->getOperand(0)->getType());
|
|
if (CE0->getType() == IntPtrTy &&
|
|
CE0->getOperand(0)->getType() == CE1->getOperand(0)->getType()) {
|
|
return ConstantFoldCompareInstOperands(
|
|
Predicate, CE0->getOperand(0), CE1->getOperand(0), DL, TLI);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// icmp eq (or x, y), 0 -> (icmp eq x, 0) & (icmp eq y, 0)
|
|
// icmp ne (or x, y), 0 -> (icmp ne x, 0) | (icmp ne y, 0)
|
|
if ((Predicate == ICmpInst::ICMP_EQ || Predicate == ICmpInst::ICMP_NE) &&
|
|
CE0->getOpcode() == Instruction::Or && Ops1->isNullValue()) {
|
|
Constant *LHS = ConstantFoldCompareInstOperands(
|
|
Predicate, CE0->getOperand(0), Ops1, DL, TLI);
|
|
Constant *RHS = ConstantFoldCompareInstOperands(
|
|
Predicate, CE0->getOperand(1), Ops1, DL, TLI);
|
|
unsigned OpC =
|
|
Predicate == ICmpInst::ICMP_EQ ? Instruction::And : Instruction::Or;
|
|
return ConstantFoldBinaryOpOperands(OpC, LHS, RHS, DL);
|
|
}
|
|
}
|
|
|
|
return ConstantExpr::getCompare(Predicate, Ops0, Ops1);
|
|
}
|
|
|
|
Constant *llvm::ConstantFoldBinaryOpOperands(unsigned Opcode, Constant *LHS,
|
|
Constant *RHS,
|
|
const DataLayout &DL) {
|
|
assert(Instruction::isBinaryOp(Opcode));
|
|
if (isa<ConstantExpr>(LHS) || isa<ConstantExpr>(RHS))
|
|
if (Constant *C = SymbolicallyEvaluateBinop(Opcode, LHS, RHS, DL))
|
|
return C;
|
|
|
|
return ConstantExpr::get(Opcode, LHS, RHS);
|
|
}
|
|
|
|
Constant *llvm::ConstantFoldCastOperand(unsigned Opcode, Constant *C,
|
|
Type *DestTy, const DataLayout &DL) {
|
|
assert(Instruction::isCast(Opcode));
|
|
switch (Opcode) {
|
|
default:
|
|
llvm_unreachable("Missing case");
|
|
case Instruction::PtrToInt:
|
|
// If the input is a inttoptr, eliminate the pair. This requires knowing
|
|
// the width of a pointer, so it can't be done in ConstantExpr::getCast.
|
|
if (auto *CE = dyn_cast<ConstantExpr>(C)) {
|
|
if (CE->getOpcode() == Instruction::IntToPtr) {
|
|
Constant *Input = CE->getOperand(0);
|
|
unsigned InWidth = Input->getType()->getScalarSizeInBits();
|
|
unsigned PtrWidth = DL.getPointerTypeSizeInBits(CE->getType());
|
|
if (PtrWidth < InWidth) {
|
|
Constant *Mask =
|
|
ConstantInt::get(CE->getContext(),
|
|
APInt::getLowBitsSet(InWidth, PtrWidth));
|
|
Input = ConstantExpr::getAnd(Input, Mask);
|
|
}
|
|
// Do a zext or trunc to get to the dest size.
|
|
return ConstantExpr::getIntegerCast(Input, DestTy, false);
|
|
}
|
|
}
|
|
return ConstantExpr::getCast(Opcode, C, DestTy);
|
|
case Instruction::IntToPtr:
|
|
// If the input is a ptrtoint, turn the pair into a ptr to ptr bitcast if
|
|
// the int size is >= the ptr size and the address spaces are the same.
|
|
// This requires knowing the width of a pointer, so it can't be done in
|
|
// ConstantExpr::getCast.
|
|
if (auto *CE = dyn_cast<ConstantExpr>(C)) {
|
|
if (CE->getOpcode() == Instruction::PtrToInt) {
|
|
Constant *SrcPtr = CE->getOperand(0);
|
|
unsigned SrcPtrSize = DL.getPointerTypeSizeInBits(SrcPtr->getType());
|
|
unsigned MidIntSize = CE->getType()->getScalarSizeInBits();
|
|
|
|
if (MidIntSize >= SrcPtrSize) {
|
|
unsigned SrcAS = SrcPtr->getType()->getPointerAddressSpace();
|
|
if (SrcAS == DestTy->getPointerAddressSpace())
|
|
return FoldBitCast(CE->getOperand(0), DestTy, DL);
|
|
}
|
|
}
|
|
}
|
|
|
|
return ConstantExpr::getCast(Opcode, C, DestTy);
|
|
case Instruction::Trunc:
|
|
case Instruction::ZExt:
|
|
case Instruction::SExt:
|
|
case Instruction::FPTrunc:
|
|
case Instruction::FPExt:
|
|
case Instruction::UIToFP:
|
|
case Instruction::SIToFP:
|
|
case Instruction::FPToUI:
|
|
case Instruction::FPToSI:
|
|
case Instruction::AddrSpaceCast:
|
|
return ConstantExpr::getCast(Opcode, C, DestTy);
|
|
case Instruction::BitCast:
|
|
return FoldBitCast(C, DestTy, DL);
|
|
}
|
|
}
|
|
|
|
Constant *llvm::ConstantFoldLoadThroughGEPConstantExpr(Constant *C,
|
|
ConstantExpr *CE) {
|
|
if (!CE->getOperand(1)->isNullValue())
|
|
return nullptr; // Do not allow stepping over the value!
|
|
|
|
// Loop over all of the operands, tracking down which value we are
|
|
// addressing.
|
|
for (unsigned i = 2, e = CE->getNumOperands(); i != e; ++i) {
|
|
C = C->getAggregateElement(CE->getOperand(i));
|
|
if (!C)
|
|
return nullptr;
|
|
}
|
|
return C;
|
|
}
|
|
|
|
Constant *
|
|
llvm::ConstantFoldLoadThroughGEPIndices(Constant *C,
|
|
ArrayRef<Constant *> Indices) {
|
|
// Loop over all of the operands, tracking down which value we are
|
|
// addressing.
|
|
for (Constant *Index : Indices) {
|
|
C = C->getAggregateElement(Index);
|
|
if (!C)
|
|
return nullptr;
|
|
}
|
|
return C;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Constant Folding for Calls
|
|
//
|
|
|
|
bool llvm::canConstantFoldCallTo(const Function *F) {
|
|
switch (F->getIntrinsicID()) {
|
|
case Intrinsic::fabs:
|
|
case Intrinsic::minnum:
|
|
case Intrinsic::maxnum:
|
|
case Intrinsic::log:
|
|
case Intrinsic::log2:
|
|
case Intrinsic::log10:
|
|
case Intrinsic::exp:
|
|
case Intrinsic::exp2:
|
|
case Intrinsic::floor:
|
|
case Intrinsic::ceil:
|
|
case Intrinsic::sqrt:
|
|
case Intrinsic::sin:
|
|
case Intrinsic::cos:
|
|
case Intrinsic::trunc:
|
|
case Intrinsic::rint:
|
|
case Intrinsic::nearbyint:
|
|
case Intrinsic::pow:
|
|
case Intrinsic::powi:
|
|
case Intrinsic::bswap:
|
|
case Intrinsic::ctpop:
|
|
case Intrinsic::ctlz:
|
|
case Intrinsic::cttz:
|
|
case Intrinsic::fma:
|
|
case Intrinsic::fmuladd:
|
|
case Intrinsic::copysign:
|
|
case Intrinsic::round:
|
|
case Intrinsic::masked_load:
|
|
case Intrinsic::sadd_with_overflow:
|
|
case Intrinsic::uadd_with_overflow:
|
|
case Intrinsic::ssub_with_overflow:
|
|
case Intrinsic::usub_with_overflow:
|
|
case Intrinsic::smul_with_overflow:
|
|
case Intrinsic::umul_with_overflow:
|
|
case Intrinsic::convert_from_fp16:
|
|
case Intrinsic::convert_to_fp16:
|
|
case Intrinsic::bitreverse:
|
|
case Intrinsic::x86_sse_cvtss2si:
|
|
case Intrinsic::x86_sse_cvtss2si64:
|
|
case Intrinsic::x86_sse_cvttss2si:
|
|
case Intrinsic::x86_sse_cvttss2si64:
|
|
case Intrinsic::x86_sse2_cvtsd2si:
|
|
case Intrinsic::x86_sse2_cvtsd2si64:
|
|
case Intrinsic::x86_sse2_cvttsd2si:
|
|
case Intrinsic::x86_sse2_cvttsd2si64:
|
|
return true;
|
|
default:
|
|
return false;
|
|
case Intrinsic::not_intrinsic: break;
|
|
}
|
|
|
|
if (!F->hasName())
|
|
return false;
|
|
StringRef Name = F->getName();
|
|
|
|
// In these cases, the check of the length is required. We don't want to
|
|
// return true for a name like "cos\0blah" which strcmp would return equal to
|
|
// "cos", but has length 8.
|
|
switch (Name[0]) {
|
|
default:
|
|
return false;
|
|
case 'a':
|
|
return Name == "acos" || Name == "asin" || Name == "atan" ||
|
|
Name == "atan2" || Name == "acosf" || Name == "asinf" ||
|
|
Name == "atanf" || Name == "atan2f";
|
|
case 'c':
|
|
return Name == "ceil" || Name == "cos" || Name == "cosh" ||
|
|
Name == "ceilf" || Name == "cosf" || Name == "coshf";
|
|
case 'e':
|
|
return Name == "exp" || Name == "exp2" || Name == "expf" || Name == "exp2f";
|
|
case 'f':
|
|
return Name == "fabs" || Name == "floor" || Name == "fmod" ||
|
|
Name == "fabsf" || Name == "floorf" || Name == "fmodf";
|
|
case 'l':
|
|
return Name == "log" || Name == "log10" || Name == "logf" ||
|
|
Name == "log10f";
|
|
case 'p':
|
|
return Name == "pow" || Name == "powf";
|
|
case 'r':
|
|
return Name == "round" || Name == "roundf";
|
|
case 's':
|
|
return Name == "sin" || Name == "sinh" || Name == "sqrt" ||
|
|
Name == "sinf" || Name == "sinhf" || Name == "sqrtf";
|
|
case 't':
|
|
return Name == "tan" || Name == "tanh" || Name == "tanf" || Name == "tanhf";
|
|
case '_':
|
|
|
|
// Check for various function names that get used for the math functions
|
|
// when the header files are preprocessed with the macro
|
|
// __FINITE_MATH_ONLY__ enabled.
|
|
// The '12' here is the length of the shortest name that can match.
|
|
// We need to check the size before looking at Name[1] and Name[2]
|
|
// so we may as well check a limit that will eliminate mismatches.
|
|
if (Name.size() < 12 || Name[1] != '_')
|
|
return false;
|
|
switch (Name[2]) {
|
|
default:
|
|
return false;
|
|
case 'a':
|
|
return Name == "__acos_finite" || Name == "__acosf_finite" ||
|
|
Name == "__asin_finite" || Name == "__asinf_finite" ||
|
|
Name == "__atan2_finite" || Name == "__atan2f_finite";
|
|
case 'c':
|
|
return Name == "__cosh_finite" || Name == "__coshf_finite";
|
|
case 'e':
|
|
return Name == "__exp_finite" || Name == "__expf_finite" ||
|
|
Name == "__exp2_finite" || Name == "__exp2f_finite";
|
|
case 'l':
|
|
return Name == "__log_finite" || Name == "__logf_finite" ||
|
|
Name == "__log10_finite" || Name == "__log10f_finite";
|
|
case 'p':
|
|
return Name == "__pow_finite" || Name == "__powf_finite";
|
|
case 's':
|
|
return Name == "__sinh_finite" || Name == "__sinhf_finite";
|
|
}
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
|
|
Constant *GetConstantFoldFPValue(double V, Type *Ty) {
|
|
if (Ty->isHalfTy()) {
|
|
APFloat APF(V);
|
|
bool unused;
|
|
APF.convert(APFloat::IEEEhalf(), APFloat::rmNearestTiesToEven, &unused);
|
|
return ConstantFP::get(Ty->getContext(), APF);
|
|
}
|
|
if (Ty->isFloatTy())
|
|
return ConstantFP::get(Ty->getContext(), APFloat((float)V));
|
|
if (Ty->isDoubleTy())
|
|
return ConstantFP::get(Ty->getContext(), APFloat(V));
|
|
llvm_unreachable("Can only constant fold half/float/double");
|
|
}
|
|
|
|
/// Clear the floating-point exception state.
|
|
inline void llvm_fenv_clearexcept() {
|
|
#if defined(HAVE_FENV_H) && HAVE_DECL_FE_ALL_EXCEPT
|
|
feclearexcept(FE_ALL_EXCEPT);
|
|
#endif
|
|
errno = 0;
|
|
}
|
|
|
|
/// Test if a floating-point exception was raised.
|
|
inline bool llvm_fenv_testexcept() {
|
|
int errno_val = errno;
|
|
if (errno_val == ERANGE || errno_val == EDOM)
|
|
return true;
|
|
#if defined(HAVE_FENV_H) && HAVE_DECL_FE_ALL_EXCEPT && HAVE_DECL_FE_INEXACT
|
|
if (fetestexcept(FE_ALL_EXCEPT & ~FE_INEXACT))
|
|
return true;
|
|
#endif
|
|
return false;
|
|
}
|
|
|
|
Constant *ConstantFoldFP(double (*NativeFP)(double), double V, Type *Ty) {
|
|
llvm_fenv_clearexcept();
|
|
V = NativeFP(V);
|
|
if (llvm_fenv_testexcept()) {
|
|
llvm_fenv_clearexcept();
|
|
return nullptr;
|
|
}
|
|
|
|
return GetConstantFoldFPValue(V, Ty);
|
|
}
|
|
|
|
Constant *ConstantFoldBinaryFP(double (*NativeFP)(double, double), double V,
|
|
double W, Type *Ty) {
|
|
llvm_fenv_clearexcept();
|
|
V = NativeFP(V, W);
|
|
if (llvm_fenv_testexcept()) {
|
|
llvm_fenv_clearexcept();
|
|
return nullptr;
|
|
}
|
|
|
|
return GetConstantFoldFPValue(V, Ty);
|
|
}
|
|
|
|
/// Attempt to fold an SSE floating point to integer conversion of a constant
|
|
/// floating point. If roundTowardZero is false, the default IEEE rounding is
|
|
/// used (toward nearest, ties to even). This matches the behavior of the
|
|
/// non-truncating SSE instructions in the default rounding mode. The desired
|
|
/// integer type Ty is used to select how many bits are available for the
|
|
/// result. Returns null if the conversion cannot be performed, otherwise
|
|
/// returns the Constant value resulting from the conversion.
|
|
Constant *ConstantFoldSSEConvertToInt(const APFloat &Val, bool roundTowardZero,
|
|
Type *Ty) {
|
|
// All of these conversion intrinsics form an integer of at most 64bits.
|
|
unsigned ResultWidth = Ty->getIntegerBitWidth();
|
|
assert(ResultWidth <= 64 &&
|
|
"Can only constant fold conversions to 64 and 32 bit ints");
|
|
|
|
uint64_t UIntVal;
|
|
bool isExact = false;
|
|
APFloat::roundingMode mode = roundTowardZero? APFloat::rmTowardZero
|
|
: APFloat::rmNearestTiesToEven;
|
|
APFloat::opStatus status =
|
|
Val.convertToInteger(makeMutableArrayRef(UIntVal), ResultWidth,
|
|
/*isSigned=*/true, mode, &isExact);
|
|
if (status != APFloat::opOK &&
|
|
(!roundTowardZero || status != APFloat::opInexact))
|
|
return nullptr;
|
|
return ConstantInt::get(Ty, UIntVal, /*isSigned=*/true);
|
|
}
|
|
|
|
double getValueAsDouble(ConstantFP *Op) {
|
|
Type *Ty = Op->getType();
|
|
|
|
if (Ty->isFloatTy())
|
|
return Op->getValueAPF().convertToFloat();
|
|
|
|
if (Ty->isDoubleTy())
|
|
return Op->getValueAPF().convertToDouble();
|
|
|
|
bool unused;
|
|
APFloat APF = Op->getValueAPF();
|
|
APF.convert(APFloat::IEEEdouble(), APFloat::rmNearestTiesToEven, &unused);
|
|
return APF.convertToDouble();
|
|
}
|
|
|
|
Constant *ConstantFoldScalarCall(StringRef Name, unsigned IntrinsicID, Type *Ty,
|
|
ArrayRef<Constant *> Operands,
|
|
const TargetLibraryInfo *TLI) {
|
|
if (Operands.size() == 1) {
|
|
if (isa<UndefValue>(Operands[0])) {
|
|
// cosine(arg) is between -1 and 1. cosine(invalid arg) is NaN
|
|
if (IntrinsicID == Intrinsic::cos)
|
|
return Constant::getNullValue(Ty);
|
|
}
|
|
if (auto *Op = dyn_cast<ConstantFP>(Operands[0])) {
|
|
if (IntrinsicID == Intrinsic::convert_to_fp16) {
|
|
APFloat Val(Op->getValueAPF());
|
|
|
|
bool lost = false;
|
|
Val.convert(APFloat::IEEEhalf(), APFloat::rmNearestTiesToEven, &lost);
|
|
|
|
return ConstantInt::get(Ty->getContext(), Val.bitcastToAPInt());
|
|
}
|
|
|
|
if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
|
|
return nullptr;
|
|
|
|
if (IntrinsicID == Intrinsic::round) {
|
|
APFloat V = Op->getValueAPF();
|
|
V.roundToIntegral(APFloat::rmNearestTiesToAway);
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::floor) {
|
|
APFloat V = Op->getValueAPF();
|
|
V.roundToIntegral(APFloat::rmTowardNegative);
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::ceil) {
|
|
APFloat V = Op->getValueAPF();
|
|
V.roundToIntegral(APFloat::rmTowardPositive);
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::trunc) {
|
|
APFloat V = Op->getValueAPF();
|
|
V.roundToIntegral(APFloat::rmTowardZero);
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::rint) {
|
|
APFloat V = Op->getValueAPF();
|
|
V.roundToIntegral(APFloat::rmNearestTiesToEven);
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::nearbyint) {
|
|
APFloat V = Op->getValueAPF();
|
|
V.roundToIntegral(APFloat::rmNearestTiesToEven);
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
}
|
|
|
|
/// We only fold functions with finite arguments. Folding NaN and inf is
|
|
/// likely to be aborted with an exception anyway, and some host libms
|
|
/// have known errors raising exceptions.
|
|
if (Op->getValueAPF().isNaN() || Op->getValueAPF().isInfinity())
|
|
return nullptr;
|
|
|
|
/// Currently APFloat versions of these functions do not exist, so we use
|
|
/// the host native double versions. Float versions are not called
|
|
/// directly but for all these it is true (float)(f((double)arg)) ==
|
|
/// f(arg). Long double not supported yet.
|
|
double V = getValueAsDouble(Op);
|
|
|
|
switch (IntrinsicID) {
|
|
default: break;
|
|
case Intrinsic::fabs:
|
|
return ConstantFoldFP(fabs, V, Ty);
|
|
case Intrinsic::log2:
|
|
return ConstantFoldFP(Log2, V, Ty);
|
|
case Intrinsic::log:
|
|
return ConstantFoldFP(log, V, Ty);
|
|
case Intrinsic::log10:
|
|
return ConstantFoldFP(log10, V, Ty);
|
|
case Intrinsic::exp:
|
|
return ConstantFoldFP(exp, V, Ty);
|
|
case Intrinsic::exp2:
|
|
return ConstantFoldFP(exp2, V, Ty);
|
|
case Intrinsic::sin:
|
|
return ConstantFoldFP(sin, V, Ty);
|
|
case Intrinsic::cos:
|
|
return ConstantFoldFP(cos, V, Ty);
|
|
case Intrinsic::sqrt:
|
|
return ConstantFoldFP(sqrt, V, Ty);
|
|
}
|
|
|
|
if (!TLI)
|
|
return nullptr;
|
|
|
|
char NameKeyChar = Name[0];
|
|
if (Name[0] == '_' && Name.size() > 2 && Name[1] == '_')
|
|
NameKeyChar = Name[2];
|
|
|
|
switch (NameKeyChar) {
|
|
case 'a':
|
|
if ((Name == "acos" && TLI->has(LibFunc_acos)) ||
|
|
(Name == "acosf" && TLI->has(LibFunc_acosf)) ||
|
|
(Name == "__acos_finite" && TLI->has(LibFunc_acos_finite)) ||
|
|
(Name == "__acosf_finite" && TLI->has(LibFunc_acosf_finite)))
|
|
return ConstantFoldFP(acos, V, Ty);
|
|
else if ((Name == "asin" && TLI->has(LibFunc_asin)) ||
|
|
(Name == "asinf" && TLI->has(LibFunc_asinf)) ||
|
|
(Name == "__asin_finite" && TLI->has(LibFunc_asin_finite)) ||
|
|
(Name == "__asinf_finite" && TLI->has(LibFunc_asinf_finite)))
|
|
return ConstantFoldFP(asin, V, Ty);
|
|
else if ((Name == "atan" && TLI->has(LibFunc_atan)) ||
|
|
(Name == "atanf" && TLI->has(LibFunc_atanf)))
|
|
return ConstantFoldFP(atan, V, Ty);
|
|
break;
|
|
case 'c':
|
|
if ((Name == "ceil" && TLI->has(LibFunc_ceil)) ||
|
|
(Name == "ceilf" && TLI->has(LibFunc_ceilf)))
|
|
return ConstantFoldFP(ceil, V, Ty);
|
|
else if ((Name == "cos" && TLI->has(LibFunc_cos)) ||
|
|
(Name == "cosf" && TLI->has(LibFunc_cosf)))
|
|
return ConstantFoldFP(cos, V, Ty);
|
|
else if ((Name == "cosh" && TLI->has(LibFunc_cosh)) ||
|
|
(Name == "coshf" && TLI->has(LibFunc_coshf)) ||
|
|
(Name == "__cosh_finite" && TLI->has(LibFunc_cosh_finite)) ||
|
|
(Name == "__coshf_finite" && TLI->has(LibFunc_coshf_finite)))
|
|
return ConstantFoldFP(cosh, V, Ty);
|
|
break;
|
|
case 'e':
|
|
if ((Name == "exp" && TLI->has(LibFunc_exp)) ||
|
|
(Name == "expf" && TLI->has(LibFunc_expf)) ||
|
|
(Name == "__exp_finite" && TLI->has(LibFunc_exp_finite)) ||
|
|
(Name == "__expf_finite" && TLI->has(LibFunc_expf_finite)))
|
|
return ConstantFoldFP(exp, V, Ty);
|
|
if ((Name == "exp2" && TLI->has(LibFunc_exp2)) ||
|
|
(Name == "exp2f" && TLI->has(LibFunc_exp2f)) ||
|
|
(Name == "__exp2_finite" && TLI->has(LibFunc_exp2_finite)) ||
|
|
(Name == "__exp2f_finite" && TLI->has(LibFunc_exp2f_finite)))
|
|
// Constant fold exp2(x) as pow(2,x) in case the host doesn't have a
|
|
// C99 library.
|
|
return ConstantFoldBinaryFP(pow, 2.0, V, Ty);
|
|
break;
|
|
case 'f':
|
|
if ((Name == "fabs" && TLI->has(LibFunc_fabs)) ||
|
|
(Name == "fabsf" && TLI->has(LibFunc_fabsf)))
|
|
return ConstantFoldFP(fabs, V, Ty);
|
|
else if ((Name == "floor" && TLI->has(LibFunc_floor)) ||
|
|
(Name == "floorf" && TLI->has(LibFunc_floorf)))
|
|
return ConstantFoldFP(floor, V, Ty);
|
|
break;
|
|
case 'l':
|
|
if ((Name == "log" && V > 0 && TLI->has(LibFunc_log)) ||
|
|
(Name == "logf" && V > 0 && TLI->has(LibFunc_logf)) ||
|
|
(Name == "__log_finite" && V > 0 &&
|
|
TLI->has(LibFunc_log_finite)) ||
|
|
(Name == "__logf_finite" && V > 0 &&
|
|
TLI->has(LibFunc_logf_finite)))
|
|
return ConstantFoldFP(log, V, Ty);
|
|
else if ((Name == "log10" && V > 0 && TLI->has(LibFunc_log10)) ||
|
|
(Name == "log10f" && V > 0 && TLI->has(LibFunc_log10f)) ||
|
|
(Name == "__log10_finite" && V > 0 &&
|
|
TLI->has(LibFunc_log10_finite)) ||
|
|
(Name == "__log10f_finite" && V > 0 &&
|
|
TLI->has(LibFunc_log10f_finite)))
|
|
return ConstantFoldFP(log10, V, Ty);
|
|
break;
|
|
case 'r':
|
|
if ((Name == "round" && TLI->has(LibFunc_round)) ||
|
|
(Name == "roundf" && TLI->has(LibFunc_roundf)))
|
|
return ConstantFoldFP(round, V, Ty);
|
|
case 's':
|
|
if ((Name == "sin" && TLI->has(LibFunc_sin)) ||
|
|
(Name == "sinf" && TLI->has(LibFunc_sinf)))
|
|
return ConstantFoldFP(sin, V, Ty);
|
|
else if ((Name == "sinh" && TLI->has(LibFunc_sinh)) ||
|
|
(Name == "sinhf" && TLI->has(LibFunc_sinhf)) ||
|
|
(Name == "__sinh_finite" && TLI->has(LibFunc_sinh_finite)) ||
|
|
(Name == "__sinhf_finite" && TLI->has(LibFunc_sinhf_finite)))
|
|
return ConstantFoldFP(sinh, V, Ty);
|
|
else if ((Name == "sqrt" && V >= 0 && TLI->has(LibFunc_sqrt)) ||
|
|
(Name == "sqrtf" && V >= 0 && TLI->has(LibFunc_sqrtf)))
|
|
return ConstantFoldFP(sqrt, V, Ty);
|
|
break;
|
|
case 't':
|
|
if ((Name == "tan" && TLI->has(LibFunc_tan)) ||
|
|
(Name == "tanf" && TLI->has(LibFunc_tanf)))
|
|
return ConstantFoldFP(tan, V, Ty);
|
|
else if ((Name == "tanh" && TLI->has(LibFunc_tanh)) ||
|
|
(Name == "tanhf" && TLI->has(LibFunc_tanhf)))
|
|
return ConstantFoldFP(tanh, V, Ty);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
if (auto *Op = dyn_cast<ConstantInt>(Operands[0])) {
|
|
switch (IntrinsicID) {
|
|
case Intrinsic::bswap:
|
|
return ConstantInt::get(Ty->getContext(), Op->getValue().byteSwap());
|
|
case Intrinsic::ctpop:
|
|
return ConstantInt::get(Ty, Op->getValue().countPopulation());
|
|
case Intrinsic::bitreverse:
|
|
return ConstantInt::get(Ty->getContext(), Op->getValue().reverseBits());
|
|
case Intrinsic::convert_from_fp16: {
|
|
APFloat Val(APFloat::IEEEhalf(), Op->getValue());
|
|
|
|
bool lost = false;
|
|
APFloat::opStatus status = Val.convert(
|
|
Ty->getFltSemantics(), APFloat::rmNearestTiesToEven, &lost);
|
|
|
|
// Conversion is always precise.
|
|
(void)status;
|
|
assert(status == APFloat::opOK && !lost &&
|
|
"Precision lost during fp16 constfolding");
|
|
|
|
return ConstantFP::get(Ty->getContext(), Val);
|
|
}
|
|
default:
|
|
return nullptr;
|
|
}
|
|
}
|
|
|
|
// Support ConstantVector in case we have an Undef in the top.
|
|
if (isa<ConstantVector>(Operands[0]) ||
|
|
isa<ConstantDataVector>(Operands[0])) {
|
|
auto *Op = cast<Constant>(Operands[0]);
|
|
switch (IntrinsicID) {
|
|
default: break;
|
|
case Intrinsic::x86_sse_cvtss2si:
|
|
case Intrinsic::x86_sse_cvtss2si64:
|
|
case Intrinsic::x86_sse2_cvtsd2si:
|
|
case Intrinsic::x86_sse2_cvtsd2si64:
|
|
if (ConstantFP *FPOp =
|
|
dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
|
|
return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
|
|
/*roundTowardZero=*/false, Ty);
|
|
case Intrinsic::x86_sse_cvttss2si:
|
|
case Intrinsic::x86_sse_cvttss2si64:
|
|
case Intrinsic::x86_sse2_cvttsd2si:
|
|
case Intrinsic::x86_sse2_cvttsd2si64:
|
|
if (ConstantFP *FPOp =
|
|
dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
|
|
return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
|
|
/*roundTowardZero=*/true, Ty);
|
|
}
|
|
}
|
|
|
|
if (isa<UndefValue>(Operands[0])) {
|
|
if (IntrinsicID == Intrinsic::bswap ||
|
|
IntrinsicID == Intrinsic::bitreverse)
|
|
return Operands[0];
|
|
return nullptr;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
if (Operands.size() == 2) {
|
|
if (auto *Op1 = dyn_cast<ConstantFP>(Operands[0])) {
|
|
if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
|
|
return nullptr;
|
|
double Op1V = getValueAsDouble(Op1);
|
|
|
|
if (auto *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
|
|
if (Op2->getType() != Op1->getType())
|
|
return nullptr;
|
|
|
|
double Op2V = getValueAsDouble(Op2);
|
|
if (IntrinsicID == Intrinsic::pow) {
|
|
return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
|
|
}
|
|
if (IntrinsicID == Intrinsic::copysign) {
|
|
APFloat V1 = Op1->getValueAPF();
|
|
const APFloat &V2 = Op2->getValueAPF();
|
|
V1.copySign(V2);
|
|
return ConstantFP::get(Ty->getContext(), V1);
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::minnum) {
|
|
const APFloat &C1 = Op1->getValueAPF();
|
|
const APFloat &C2 = Op2->getValueAPF();
|
|
return ConstantFP::get(Ty->getContext(), minnum(C1, C2));
|
|
}
|
|
|
|
if (IntrinsicID == Intrinsic::maxnum) {
|
|
const APFloat &C1 = Op1->getValueAPF();
|
|
const APFloat &C2 = Op2->getValueAPF();
|
|
return ConstantFP::get(Ty->getContext(), maxnum(C1, C2));
|
|
}
|
|
|
|
if (!TLI)
|
|
return nullptr;
|
|
if ((Name == "pow" && TLI->has(LibFunc_pow)) ||
|
|
(Name == "powf" && TLI->has(LibFunc_powf)) ||
|
|
(Name == "__pow_finite" && TLI->has(LibFunc_pow_finite)) ||
|
|
(Name == "__powf_finite" && TLI->has(LibFunc_powf_finite)))
|
|
return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
|
|
if ((Name == "fmod" && TLI->has(LibFunc_fmod)) ||
|
|
(Name == "fmodf" && TLI->has(LibFunc_fmodf)))
|
|
return ConstantFoldBinaryFP(fmod, Op1V, Op2V, Ty);
|
|
if ((Name == "atan2" && TLI->has(LibFunc_atan2)) ||
|
|
(Name == "atan2f" && TLI->has(LibFunc_atan2f)) ||
|
|
(Name == "__atan2_finite" && TLI->has(LibFunc_atan2_finite)) ||
|
|
(Name == "__atan2f_finite" && TLI->has(LibFunc_atan2f_finite)))
|
|
return ConstantFoldBinaryFP(atan2, Op1V, Op2V, Ty);
|
|
} else if (auto *Op2C = dyn_cast<ConstantInt>(Operands[1])) {
|
|
if (IntrinsicID == Intrinsic::powi && Ty->isHalfTy())
|
|
return ConstantFP::get(Ty->getContext(),
|
|
APFloat((float)std::pow((float)Op1V,
|
|
(int)Op2C->getZExtValue())));
|
|
if (IntrinsicID == Intrinsic::powi && Ty->isFloatTy())
|
|
return ConstantFP::get(Ty->getContext(),
|
|
APFloat((float)std::pow((float)Op1V,
|
|
(int)Op2C->getZExtValue())));
|
|
if (IntrinsicID == Intrinsic::powi && Ty->isDoubleTy())
|
|
return ConstantFP::get(Ty->getContext(),
|
|
APFloat((double)std::pow((double)Op1V,
|
|
(int)Op2C->getZExtValue())));
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
if (auto *Op1 = dyn_cast<ConstantInt>(Operands[0])) {
|
|
if (auto *Op2 = dyn_cast<ConstantInt>(Operands[1])) {
|
|
switch (IntrinsicID) {
|
|
default: break;
|
|
case Intrinsic::sadd_with_overflow:
|
|
case Intrinsic::uadd_with_overflow:
|
|
case Intrinsic::ssub_with_overflow:
|
|
case Intrinsic::usub_with_overflow:
|
|
case Intrinsic::smul_with_overflow:
|
|
case Intrinsic::umul_with_overflow: {
|
|
APInt Res;
|
|
bool Overflow;
|
|
switch (IntrinsicID) {
|
|
default: llvm_unreachable("Invalid case");
|
|
case Intrinsic::sadd_with_overflow:
|
|
Res = Op1->getValue().sadd_ov(Op2->getValue(), Overflow);
|
|
break;
|
|
case Intrinsic::uadd_with_overflow:
|
|
Res = Op1->getValue().uadd_ov(Op2->getValue(), Overflow);
|
|
break;
|
|
case Intrinsic::ssub_with_overflow:
|
|
Res = Op1->getValue().ssub_ov(Op2->getValue(), Overflow);
|
|
break;
|
|
case Intrinsic::usub_with_overflow:
|
|
Res = Op1->getValue().usub_ov(Op2->getValue(), Overflow);
|
|
break;
|
|
case Intrinsic::smul_with_overflow:
|
|
Res = Op1->getValue().smul_ov(Op2->getValue(), Overflow);
|
|
break;
|
|
case Intrinsic::umul_with_overflow:
|
|
Res = Op1->getValue().umul_ov(Op2->getValue(), Overflow);
|
|
break;
|
|
}
|
|
Constant *Ops[] = {
|
|
ConstantInt::get(Ty->getContext(), Res),
|
|
ConstantInt::get(Type::getInt1Ty(Ty->getContext()), Overflow)
|
|
};
|
|
return ConstantStruct::get(cast<StructType>(Ty), Ops);
|
|
}
|
|
case Intrinsic::cttz:
|
|
if (Op2->isOne() && Op1->isZero()) // cttz(0, 1) is undef.
|
|
return UndefValue::get(Ty);
|
|
return ConstantInt::get(Ty, Op1->getValue().countTrailingZeros());
|
|
case Intrinsic::ctlz:
|
|
if (Op2->isOne() && Op1->isZero()) // ctlz(0, 1) is undef.
|
|
return UndefValue::get(Ty);
|
|
return ConstantInt::get(Ty, Op1->getValue().countLeadingZeros());
|
|
}
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
if (Operands.size() != 3)
|
|
return nullptr;
|
|
|
|
if (const auto *Op1 = dyn_cast<ConstantFP>(Operands[0])) {
|
|
if (const auto *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
|
|
if (const auto *Op3 = dyn_cast<ConstantFP>(Operands[2])) {
|
|
switch (IntrinsicID) {
|
|
default: break;
|
|
case Intrinsic::fma:
|
|
case Intrinsic::fmuladd: {
|
|
APFloat V = Op1->getValueAPF();
|
|
APFloat::opStatus s = V.fusedMultiplyAdd(Op2->getValueAPF(),
|
|
Op3->getValueAPF(),
|
|
APFloat::rmNearestTiesToEven);
|
|
if (s != APFloat::opInvalidOp)
|
|
return ConstantFP::get(Ty->getContext(), V);
|
|
|
|
return nullptr;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Constant *ConstantFoldVectorCall(StringRef Name, unsigned IntrinsicID,
|
|
VectorType *VTy, ArrayRef<Constant *> Operands,
|
|
const DataLayout &DL,
|
|
const TargetLibraryInfo *TLI) {
|
|
SmallVector<Constant *, 4> Result(VTy->getNumElements());
|
|
SmallVector<Constant *, 4> Lane(Operands.size());
|
|
Type *Ty = VTy->getElementType();
|
|
|
|
if (IntrinsicID == Intrinsic::masked_load) {
|
|
auto *SrcPtr = Operands[0];
|
|
auto *Mask = Operands[2];
|
|
auto *Passthru = Operands[3];
|
|
|
|
Constant *VecData = ConstantFoldLoadFromConstPtr(SrcPtr, VTy, DL);
|
|
|
|
SmallVector<Constant *, 32> NewElements;
|
|
for (unsigned I = 0, E = VTy->getNumElements(); I != E; ++I) {
|
|
auto *MaskElt = Mask->getAggregateElement(I);
|
|
if (!MaskElt)
|
|
break;
|
|
auto *PassthruElt = Passthru->getAggregateElement(I);
|
|
auto *VecElt = VecData ? VecData->getAggregateElement(I) : nullptr;
|
|
if (isa<UndefValue>(MaskElt)) {
|
|
if (PassthruElt)
|
|
NewElements.push_back(PassthruElt);
|
|
else if (VecElt)
|
|
NewElements.push_back(VecElt);
|
|
else
|
|
return nullptr;
|
|
}
|
|
if (MaskElt->isNullValue()) {
|
|
if (!PassthruElt)
|
|
return nullptr;
|
|
NewElements.push_back(PassthruElt);
|
|
} else if (MaskElt->isOneValue()) {
|
|
if (!VecElt)
|
|
return nullptr;
|
|
NewElements.push_back(VecElt);
|
|
} else {
|
|
return nullptr;
|
|
}
|
|
}
|
|
if (NewElements.size() != VTy->getNumElements())
|
|
return nullptr;
|
|
return ConstantVector::get(NewElements);
|
|
}
|
|
|
|
for (unsigned I = 0, E = VTy->getNumElements(); I != E; ++I) {
|
|
// Gather a column of constants.
|
|
for (unsigned J = 0, JE = Operands.size(); J != JE; ++J) {
|
|
Constant *Agg = Operands[J]->getAggregateElement(I);
|
|
if (!Agg)
|
|
return nullptr;
|
|
|
|
Lane[J] = Agg;
|
|
}
|
|
|
|
// Use the regular scalar folding to simplify this column.
|
|
Constant *Folded = ConstantFoldScalarCall(Name, IntrinsicID, Ty, Lane, TLI);
|
|
if (!Folded)
|
|
return nullptr;
|
|
Result[I] = Folded;
|
|
}
|
|
|
|
return ConstantVector::get(Result);
|
|
}
|
|
|
|
} // end anonymous namespace
|
|
|
|
Constant *
|
|
llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands,
|
|
const TargetLibraryInfo *TLI) {
|
|
if (!F->hasName())
|
|
return nullptr;
|
|
StringRef Name = F->getName();
|
|
|
|
Type *Ty = F->getReturnType();
|
|
|
|
if (auto *VTy = dyn_cast<VectorType>(Ty))
|
|
return ConstantFoldVectorCall(Name, F->getIntrinsicID(), VTy, Operands,
|
|
F->getParent()->getDataLayout(), TLI);
|
|
|
|
return ConstantFoldScalarCall(Name, F->getIntrinsicID(), Ty, Operands, TLI);
|
|
}
|
|
|
|
bool llvm::isMathLibCallNoop(CallSite CS, const TargetLibraryInfo *TLI) {
|
|
// FIXME: Refactor this code; this duplicates logic in LibCallsShrinkWrap
|
|
// (and to some extent ConstantFoldScalarCall).
|
|
Function *F = CS.getCalledFunction();
|
|
if (!F)
|
|
return false;
|
|
|
|
LibFunc Func;
|
|
if (!TLI || !TLI->getLibFunc(*F, Func))
|
|
return false;
|
|
|
|
if (CS.getNumArgOperands() == 1) {
|
|
if (ConstantFP *OpC = dyn_cast<ConstantFP>(CS.getArgOperand(0))) {
|
|
const APFloat &Op = OpC->getValueAPF();
|
|
switch (Func) {
|
|
case LibFunc_logl:
|
|
case LibFunc_log:
|
|
case LibFunc_logf:
|
|
case LibFunc_log2l:
|
|
case LibFunc_log2:
|
|
case LibFunc_log2f:
|
|
case LibFunc_log10l:
|
|
case LibFunc_log10:
|
|
case LibFunc_log10f:
|
|
return Op.isNaN() || (!Op.isZero() && !Op.isNegative());
|
|
|
|
case LibFunc_expl:
|
|
case LibFunc_exp:
|
|
case LibFunc_expf:
|
|
// FIXME: These boundaries are slightly conservative.
|
|
if (OpC->getType()->isDoubleTy())
|
|
return Op.compare(APFloat(-745.0)) != APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(709.0)) != APFloat::cmpGreaterThan;
|
|
if (OpC->getType()->isFloatTy())
|
|
return Op.compare(APFloat(-103.0f)) != APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(88.0f)) != APFloat::cmpGreaterThan;
|
|
break;
|
|
|
|
case LibFunc_exp2l:
|
|
case LibFunc_exp2:
|
|
case LibFunc_exp2f:
|
|
// FIXME: These boundaries are slightly conservative.
|
|
if (OpC->getType()->isDoubleTy())
|
|
return Op.compare(APFloat(-1074.0)) != APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(1023.0)) != APFloat::cmpGreaterThan;
|
|
if (OpC->getType()->isFloatTy())
|
|
return Op.compare(APFloat(-149.0f)) != APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(127.0f)) != APFloat::cmpGreaterThan;
|
|
break;
|
|
|
|
case LibFunc_sinl:
|
|
case LibFunc_sin:
|
|
case LibFunc_sinf:
|
|
case LibFunc_cosl:
|
|
case LibFunc_cos:
|
|
case LibFunc_cosf:
|
|
return !Op.isInfinity();
|
|
|
|
case LibFunc_tanl:
|
|
case LibFunc_tan:
|
|
case LibFunc_tanf: {
|
|
// FIXME: Stop using the host math library.
|
|
// FIXME: The computation isn't done in the right precision.
|
|
Type *Ty = OpC->getType();
|
|
if (Ty->isDoubleTy() || Ty->isFloatTy() || Ty->isHalfTy()) {
|
|
double OpV = getValueAsDouble(OpC);
|
|
return ConstantFoldFP(tan, OpV, Ty) != nullptr;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case LibFunc_asinl:
|
|
case LibFunc_asin:
|
|
case LibFunc_asinf:
|
|
case LibFunc_acosl:
|
|
case LibFunc_acos:
|
|
case LibFunc_acosf:
|
|
return Op.compare(APFloat(Op.getSemantics(), "-1")) !=
|
|
APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(Op.getSemantics(), "1")) !=
|
|
APFloat::cmpGreaterThan;
|
|
|
|
case LibFunc_sinh:
|
|
case LibFunc_cosh:
|
|
case LibFunc_sinhf:
|
|
case LibFunc_coshf:
|
|
case LibFunc_sinhl:
|
|
case LibFunc_coshl:
|
|
// FIXME: These boundaries are slightly conservative.
|
|
if (OpC->getType()->isDoubleTy())
|
|
return Op.compare(APFloat(-710.0)) != APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(710.0)) != APFloat::cmpGreaterThan;
|
|
if (OpC->getType()->isFloatTy())
|
|
return Op.compare(APFloat(-89.0f)) != APFloat::cmpLessThan &&
|
|
Op.compare(APFloat(89.0f)) != APFloat::cmpGreaterThan;
|
|
break;
|
|
|
|
case LibFunc_sqrtl:
|
|
case LibFunc_sqrt:
|
|
case LibFunc_sqrtf:
|
|
return Op.isNaN() || Op.isZero() || !Op.isNegative();
|
|
|
|
// FIXME: Add more functions: sqrt_finite, atanh, expm1, log1p,
|
|
// maybe others?
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (CS.getNumArgOperands() == 2) {
|
|
ConstantFP *Op0C = dyn_cast<ConstantFP>(CS.getArgOperand(0));
|
|
ConstantFP *Op1C = dyn_cast<ConstantFP>(CS.getArgOperand(1));
|
|
if (Op0C && Op1C) {
|
|
const APFloat &Op0 = Op0C->getValueAPF();
|
|
const APFloat &Op1 = Op1C->getValueAPF();
|
|
|
|
switch (Func) {
|
|
case LibFunc_powl:
|
|
case LibFunc_pow:
|
|
case LibFunc_powf: {
|
|
// FIXME: Stop using the host math library.
|
|
// FIXME: The computation isn't done in the right precision.
|
|
Type *Ty = Op0C->getType();
|
|
if (Ty->isDoubleTy() || Ty->isFloatTy() || Ty->isHalfTy()) {
|
|
if (Ty == Op1C->getType()) {
|
|
double Op0V = getValueAsDouble(Op0C);
|
|
double Op1V = getValueAsDouble(Op1C);
|
|
return ConstantFoldBinaryFP(pow, Op0V, Op1V, Ty) != nullptr;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
case LibFunc_fmodl:
|
|
case LibFunc_fmod:
|
|
case LibFunc_fmodf:
|
|
return Op0.isNaN() || Op1.isNaN() ||
|
|
(!Op0.isInfinity() && !Op1.isZero());
|
|
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|