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author | shadchin <shadchin@yandex-team.ru> | 2022-02-10 16:44:39 +0300 |
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committer | Daniil Cherednik <dcherednik@yandex-team.ru> | 2022-02-10 16:44:39 +0300 |
commit | e9656aae26e0358d5378e5b63dcac5c8dbe0e4d0 (patch) | |
tree | 64175d5cadab313b3e7039ebaa06c5bc3295e274 /contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h | |
parent | 2598ef1d0aee359b4b6d5fdd1758916d5907d04f (diff) | |
download | ydb-e9656aae26e0358d5378e5b63dcac5c8dbe0e4d0.tar.gz |
Restoring authorship annotation for <shadchin@yandex-team.ru>. Commit 2 of 2.
Diffstat (limited to 'contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h')
-rw-r--r-- | contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h | 952 |
1 files changed, 476 insertions, 476 deletions
diff --git a/contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h b/contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h index f457cd8817..1c4b0332d1 100644 --- a/contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h +++ b/contrib/libs/llvm12/include/llvm/IR/FixedPointBuilder.h @@ -1,476 +1,476 @@ -#pragma once - -#ifdef __GNUC__ -#pragma GCC diagnostic push -#pragma GCC diagnostic ignored "-Wunused-parameter" -#endif - -//===- llvm/FixedPointBuilder.h - Builder for fixed-point ops ---*- C++ -*-===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -// -//===----------------------------------------------------------------------===// -// -// This file defines the FixedPointBuilder class, which is used as a convenient -// way to lower fixed-point arithmetic operations to LLVM IR. -// -//===----------------------------------------------------------------------===// - -#ifndef LLVM_IR_FIXEDPOINTBUILDER_H -#define LLVM_IR_FIXEDPOINTBUILDER_H - -#include "llvm/ADT/APFixedPoint.h" -#include "llvm/IR/Constant.h" -#include "llvm/IR/Constants.h" -#include "llvm/IR/IRBuilder.h" -#include "llvm/IR/InstrTypes.h" -#include "llvm/IR/Instruction.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/Intrinsics.h" -#include "llvm/IR/Type.h" -#include "llvm/IR/Value.h" - -namespace llvm { - -template <class IRBuilderTy> class FixedPointBuilder { - IRBuilderTy &B; - - Value *Convert(Value *Src, const FixedPointSemantics &SrcSema, - const FixedPointSemantics &DstSema, bool DstIsInteger) { - unsigned SrcWidth = SrcSema.getWidth(); - unsigned DstWidth = DstSema.getWidth(); - unsigned SrcScale = SrcSema.getScale(); - unsigned DstScale = DstSema.getScale(); - bool SrcIsSigned = SrcSema.isSigned(); - bool DstIsSigned = DstSema.isSigned(); - - Type *DstIntTy = B.getIntNTy(DstWidth); - - Value *Result = Src; - unsigned ResultWidth = SrcWidth; - - // Downscale. - if (DstScale < SrcScale) { - // When converting to integers, we round towards zero. For negative - // numbers, right shifting rounds towards negative infinity. In this case, - // we can just round up before shifting. - if (DstIsInteger && SrcIsSigned) { - Value *Zero = Constant::getNullValue(Result->getType()); - Value *IsNegative = B.CreateICmpSLT(Result, Zero); - Value *LowBits = ConstantInt::get( - B.getContext(), APInt::getLowBitsSet(ResultWidth, SrcScale)); - Value *Rounded = B.CreateAdd(Result, LowBits); - Result = B.CreateSelect(IsNegative, Rounded, Result); - } - - Result = SrcIsSigned - ? B.CreateAShr(Result, SrcScale - DstScale, "downscale") - : B.CreateLShr(Result, SrcScale - DstScale, "downscale"); - } - - if (!DstSema.isSaturated()) { - // Resize. - Result = B.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize"); - - // Upscale. - if (DstScale > SrcScale) - Result = B.CreateShl(Result, DstScale - SrcScale, "upscale"); - } else { - // Adjust the number of fractional bits. - if (DstScale > SrcScale) { - // Compare to DstWidth to prevent resizing twice. - ResultWidth = std::max(SrcWidth + DstScale - SrcScale, DstWidth); - Type *UpscaledTy = B.getIntNTy(ResultWidth); - Result = B.CreateIntCast(Result, UpscaledTy, SrcIsSigned, "resize"); - Result = B.CreateShl(Result, DstScale - SrcScale, "upscale"); - } - - // Handle saturation. - bool LessIntBits = DstSema.getIntegralBits() < SrcSema.getIntegralBits(); - if (LessIntBits) { - Value *Max = ConstantInt::get( - B.getContext(), - APFixedPoint::getMax(DstSema).getValue().extOrTrunc(ResultWidth)); - Value *TooHigh = SrcIsSigned ? B.CreateICmpSGT(Result, Max) - : B.CreateICmpUGT(Result, Max); - Result = B.CreateSelect(TooHigh, Max, Result, "satmax"); - } - // Cannot overflow min to dest type if src is unsigned since all fixed - // point types can cover the unsigned min of 0. - if (SrcIsSigned && (LessIntBits || !DstIsSigned)) { - Value *Min = ConstantInt::get( - B.getContext(), - APFixedPoint::getMin(DstSema).getValue().extOrTrunc(ResultWidth)); - Value *TooLow = B.CreateICmpSLT(Result, Min); - Result = B.CreateSelect(TooLow, Min, Result, "satmin"); - } - - // Resize the integer part to get the final destination size. - if (ResultWidth != DstWidth) - Result = B.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize"); - } - return Result; - } - - /// Get the common semantic for two semantics, with the added imposition that - /// saturated padded types retain the padding bit. - FixedPointSemantics - getCommonBinopSemantic(const FixedPointSemantics &LHSSema, - const FixedPointSemantics &RHSSema) { - auto C = LHSSema.getCommonSemantics(RHSSema); - bool BothPadded = - LHSSema.hasUnsignedPadding() && RHSSema.hasUnsignedPadding(); - return FixedPointSemantics( - C.getWidth() + (unsigned)(BothPadded && C.isSaturated()), C.getScale(), - C.isSigned(), C.isSaturated(), BothPadded); - } - - /// Given a floating point type and a fixed-point semantic, return a floating - /// point type which can accommodate the fixed-point semantic. This is either - /// \p Ty, or a floating point type with a larger exponent than Ty. - Type *getAccommodatingFloatType(Type *Ty, const FixedPointSemantics &Sema) { - const fltSemantics *FloatSema = &Ty->getFltSemantics(); - while (!Sema.fitsInFloatSemantics(*FloatSema)) - FloatSema = APFixedPoint::promoteFloatSemantics(FloatSema); - return Type::getFloatingPointTy(Ty->getContext(), *FloatSema); - } - -public: - FixedPointBuilder(IRBuilderTy &Builder) : B(Builder) {} - - /// Convert an integer value representing a fixed-point number from one - /// fixed-point semantic to another fixed-point semantic. - /// \p Src - The source value - /// \p SrcSema - The fixed-point semantic of the source value - /// \p DstSema - The resulting fixed-point semantic - Value *CreateFixedToFixed(Value *Src, const FixedPointSemantics &SrcSema, - const FixedPointSemantics &DstSema) { - return Convert(Src, SrcSema, DstSema, false); - } - - /// Convert an integer value representing a fixed-point number to an integer - /// with the given bit width and signedness. - /// \p Src - The source value - /// \p SrcSema - The fixed-point semantic of the source value - /// \p DstWidth - The bit width of the result value - /// \p DstIsSigned - The signedness of the result value - Value *CreateFixedToInteger(Value *Src, const FixedPointSemantics &SrcSema, - unsigned DstWidth, bool DstIsSigned) { - return Convert( - Src, SrcSema, - FixedPointSemantics::GetIntegerSemantics(DstWidth, DstIsSigned), true); - } - - /// Convert an integer value with the given signedness to an integer value - /// representing the given fixed-point semantic. - /// \p Src - The source value - /// \p SrcIsSigned - The signedness of the source value - /// \p DstSema - The resulting fixed-point semantic - Value *CreateIntegerToFixed(Value *Src, unsigned SrcIsSigned, - const FixedPointSemantics &DstSema) { - return Convert(Src, - FixedPointSemantics::GetIntegerSemantics( - Src->getType()->getScalarSizeInBits(), SrcIsSigned), - DstSema, false); - } - - Value *CreateFixedToFloating(Value *Src, const FixedPointSemantics &SrcSema, - Type *DstTy) { - Value *Result; - Type *OpTy = getAccommodatingFloatType(DstTy, SrcSema); - // Convert the raw fixed-point value directly to floating point. If the - // value is too large to fit, it will be rounded, not truncated. - Result = SrcSema.isSigned() ? B.CreateSIToFP(Src, OpTy) - : B.CreateUIToFP(Src, OpTy); - // Rescale the integral-in-floating point by the scaling factor. This is - // lossless, except for overflow to infinity which is unlikely. - Result = B.CreateFMul(Result, - ConstantFP::get(OpTy, std::pow(2, -(int)SrcSema.getScale()))); - if (OpTy != DstTy) - Result = B.CreateFPTrunc(Result, DstTy); - return Result; - } - - Value *CreateFloatingToFixed(Value *Src, const FixedPointSemantics &DstSema) { - bool UseSigned = DstSema.isSigned() || DstSema.hasUnsignedPadding(); - Value *Result = Src; - Type *OpTy = getAccommodatingFloatType(Src->getType(), DstSema); - if (OpTy != Src->getType()) - Result = B.CreateFPExt(Result, OpTy); - // Rescale the floating point value so that its significant bits (for the - // purposes of the conversion) are in the integral range. - Result = B.CreateFMul(Result, - ConstantFP::get(OpTy, std::pow(2, DstSema.getScale()))); - - Type *ResultTy = B.getIntNTy(DstSema.getWidth()); - if (DstSema.isSaturated()) { - Intrinsic::ID IID = - UseSigned ? Intrinsic::fptosi_sat : Intrinsic::fptoui_sat; - Result = B.CreateIntrinsic(IID, {ResultTy, OpTy}, {Result}); - } else { - Result = UseSigned ? B.CreateFPToSI(Result, ResultTy) - : B.CreateFPToUI(Result, ResultTy); - } - - // When saturating unsigned-with-padding using signed operations, we may - // get negative values. Emit an extra clamp to zero. - if (DstSema.isSaturated() && DstSema.hasUnsignedPadding()) { - Constant *Zero = Constant::getNullValue(Result->getType()); - Result = - B.CreateSelect(B.CreateICmpSLT(Result, Zero), Zero, Result, "satmin"); - } - - return Result; - } - - /// Add two fixed-point values and return the result in their common semantic. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateAdd(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - Value *Result; - if (CommonSema.isSaturated()) { - Intrinsic::ID IID = UseSigned ? Intrinsic::sadd_sat : Intrinsic::uadd_sat; - Result = B.CreateBinaryIntrinsic(IID, WideLHS, WideRHS); - } else { - Result = B.CreateAdd(WideLHS, WideRHS); - } - - return CreateFixedToFixed(Result, CommonSema, - LHSSema.getCommonSemantics(RHSSema)); - } - - /// Subtract two fixed-point values and return the result in their common - /// semantic. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateSub(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - Value *Result; - if (CommonSema.isSaturated()) { - Intrinsic::ID IID = UseSigned ? Intrinsic::ssub_sat : Intrinsic::usub_sat; - Result = B.CreateBinaryIntrinsic(IID, WideLHS, WideRHS); - } else { - Result = B.CreateSub(WideLHS, WideRHS); - } - - // Subtraction can end up below 0 for padded unsigned operations, so emit - // an extra clamp in that case. - if (CommonSema.isSaturated() && CommonSema.hasUnsignedPadding()) { - Constant *Zero = Constant::getNullValue(Result->getType()); - Result = - B.CreateSelect(B.CreateICmpSLT(Result, Zero), Zero, Result, "satmin"); - } - - return CreateFixedToFixed(Result, CommonSema, - LHSSema.getCommonSemantics(RHSSema)); - } - - /// Multiply two fixed-point values and return the result in their common - /// semantic. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateMul(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - Intrinsic::ID IID; - if (CommonSema.isSaturated()) { - IID = UseSigned ? Intrinsic::smul_fix_sat : Intrinsic::umul_fix_sat; - } else { - IID = UseSigned ? Intrinsic::smul_fix : Intrinsic::umul_fix; - } - Value *Result = B.CreateIntrinsic( - IID, {WideLHS->getType()}, - {WideLHS, WideRHS, B.getInt32(CommonSema.getScale())}); - - return CreateFixedToFixed(Result, CommonSema, - LHSSema.getCommonSemantics(RHSSema)); - } - - /// Divide two fixed-point values and return the result in their common - /// semantic. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateDiv(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - Intrinsic::ID IID; - if (CommonSema.isSaturated()) { - IID = UseSigned ? Intrinsic::sdiv_fix_sat : Intrinsic::udiv_fix_sat; - } else { - IID = UseSigned ? Intrinsic::sdiv_fix : Intrinsic::udiv_fix; - } - Value *Result = B.CreateIntrinsic( - IID, {WideLHS->getType()}, - {WideLHS, WideRHS, B.getInt32(CommonSema.getScale())}); - - return CreateFixedToFixed(Result, CommonSema, - LHSSema.getCommonSemantics(RHSSema)); - } - - /// Left shift a fixed-point value by an unsigned integer value. The integer - /// value can be any bit width. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - Value *CreateShl(Value *LHS, const FixedPointSemantics &LHSSema, Value *RHS) { - bool UseSigned = LHSSema.isSigned() || LHSSema.hasUnsignedPadding(); - - RHS = B.CreateIntCast(RHS, LHS->getType(), /*IsSigned=*/false); - - Value *Result; - if (LHSSema.isSaturated()) { - Intrinsic::ID IID = UseSigned ? Intrinsic::sshl_sat : Intrinsic::ushl_sat; - Result = B.CreateBinaryIntrinsic(IID, LHS, RHS); - } else { - Result = B.CreateShl(LHS, RHS); - } - - return Result; - } - - /// Right shift a fixed-point value by an unsigned integer value. The integer - /// value can be any bit width. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - Value *CreateShr(Value *LHS, const FixedPointSemantics &LHSSema, Value *RHS) { - RHS = B.CreateIntCast(RHS, LHS->getType(), false); - - return LHSSema.isSigned() ? B.CreateAShr(LHS, RHS) : B.CreateLShr(LHS, RHS); - } - - /// Compare two fixed-point values for equality. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateEQ(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - return B.CreateICmpEQ(WideLHS, WideRHS); - } - - /// Compare two fixed-point values for inequality. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateNE(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - return B.CreateICmpNE(WideLHS, WideRHS); - } - - /// Compare two fixed-point values as LHS < RHS. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateLT(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - return CommonSema.isSigned() ? B.CreateICmpSLT(WideLHS, WideRHS) - : B.CreateICmpULT(WideLHS, WideRHS); - } - - /// Compare two fixed-point values as LHS <= RHS. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateLE(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - return CommonSema.isSigned() ? B.CreateICmpSLE(WideLHS, WideRHS) - : B.CreateICmpULE(WideLHS, WideRHS); - } - - /// Compare two fixed-point values as LHS > RHS. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateGT(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - return CommonSema.isSigned() ? B.CreateICmpSGT(WideLHS, WideRHS) - : B.CreateICmpUGT(WideLHS, WideRHS); - } - - /// Compare two fixed-point values as LHS >= RHS. - /// \p LHS - The left hand side - /// \p LHSSema - The semantic of the left hand side - /// \p RHS - The right hand side - /// \p RHSSema - The semantic of the right hand side - Value *CreateGE(Value *LHS, const FixedPointSemantics &LHSSema, - Value *RHS, const FixedPointSemantics &RHSSema) { - auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); - - Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); - Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); - - return CommonSema.isSigned() ? B.CreateICmpSGE(WideLHS, WideRHS) - : B.CreateICmpUGE(WideLHS, WideRHS); - } -}; - -} // end namespace llvm - -#endif // LLVM_IR_FIXEDPOINTBUILDER_H - -#ifdef __GNUC__ -#pragma GCC diagnostic pop -#endif +#pragma once + +#ifdef __GNUC__ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wunused-parameter" +#endif + +//===- llvm/FixedPointBuilder.h - Builder for fixed-point ops ---*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file defines the FixedPointBuilder class, which is used as a convenient +// way to lower fixed-point arithmetic operations to LLVM IR. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_IR_FIXEDPOINTBUILDER_H +#define LLVM_IR_FIXEDPOINTBUILDER_H + +#include "llvm/ADT/APFixedPoint.h" +#include "llvm/IR/Constant.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/IRBuilder.h" +#include "llvm/IR/InstrTypes.h" +#include "llvm/IR/Instruction.h" +#include "llvm/IR/IntrinsicInst.h" +#include "llvm/IR/Intrinsics.h" +#include "llvm/IR/Type.h" +#include "llvm/IR/Value.h" + +namespace llvm { + +template <class IRBuilderTy> class FixedPointBuilder { + IRBuilderTy &B; + + Value *Convert(Value *Src, const FixedPointSemantics &SrcSema, + const FixedPointSemantics &DstSema, bool DstIsInteger) { + unsigned SrcWidth = SrcSema.getWidth(); + unsigned DstWidth = DstSema.getWidth(); + unsigned SrcScale = SrcSema.getScale(); + unsigned DstScale = DstSema.getScale(); + bool SrcIsSigned = SrcSema.isSigned(); + bool DstIsSigned = DstSema.isSigned(); + + Type *DstIntTy = B.getIntNTy(DstWidth); + + Value *Result = Src; + unsigned ResultWidth = SrcWidth; + + // Downscale. + if (DstScale < SrcScale) { + // When converting to integers, we round towards zero. For negative + // numbers, right shifting rounds towards negative infinity. In this case, + // we can just round up before shifting. + if (DstIsInteger && SrcIsSigned) { + Value *Zero = Constant::getNullValue(Result->getType()); + Value *IsNegative = B.CreateICmpSLT(Result, Zero); + Value *LowBits = ConstantInt::get( + B.getContext(), APInt::getLowBitsSet(ResultWidth, SrcScale)); + Value *Rounded = B.CreateAdd(Result, LowBits); + Result = B.CreateSelect(IsNegative, Rounded, Result); + } + + Result = SrcIsSigned + ? B.CreateAShr(Result, SrcScale - DstScale, "downscale") + : B.CreateLShr(Result, SrcScale - DstScale, "downscale"); + } + + if (!DstSema.isSaturated()) { + // Resize. + Result = B.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize"); + + // Upscale. + if (DstScale > SrcScale) + Result = B.CreateShl(Result, DstScale - SrcScale, "upscale"); + } else { + // Adjust the number of fractional bits. + if (DstScale > SrcScale) { + // Compare to DstWidth to prevent resizing twice. + ResultWidth = std::max(SrcWidth + DstScale - SrcScale, DstWidth); + Type *UpscaledTy = B.getIntNTy(ResultWidth); + Result = B.CreateIntCast(Result, UpscaledTy, SrcIsSigned, "resize"); + Result = B.CreateShl(Result, DstScale - SrcScale, "upscale"); + } + + // Handle saturation. + bool LessIntBits = DstSema.getIntegralBits() < SrcSema.getIntegralBits(); + if (LessIntBits) { + Value *Max = ConstantInt::get( + B.getContext(), + APFixedPoint::getMax(DstSema).getValue().extOrTrunc(ResultWidth)); + Value *TooHigh = SrcIsSigned ? B.CreateICmpSGT(Result, Max) + : B.CreateICmpUGT(Result, Max); + Result = B.CreateSelect(TooHigh, Max, Result, "satmax"); + } + // Cannot overflow min to dest type if src is unsigned since all fixed + // point types can cover the unsigned min of 0. + if (SrcIsSigned && (LessIntBits || !DstIsSigned)) { + Value *Min = ConstantInt::get( + B.getContext(), + APFixedPoint::getMin(DstSema).getValue().extOrTrunc(ResultWidth)); + Value *TooLow = B.CreateICmpSLT(Result, Min); + Result = B.CreateSelect(TooLow, Min, Result, "satmin"); + } + + // Resize the integer part to get the final destination size. + if (ResultWidth != DstWidth) + Result = B.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize"); + } + return Result; + } + + /// Get the common semantic for two semantics, with the added imposition that + /// saturated padded types retain the padding bit. + FixedPointSemantics + getCommonBinopSemantic(const FixedPointSemantics &LHSSema, + const FixedPointSemantics &RHSSema) { + auto C = LHSSema.getCommonSemantics(RHSSema); + bool BothPadded = + LHSSema.hasUnsignedPadding() && RHSSema.hasUnsignedPadding(); + return FixedPointSemantics( + C.getWidth() + (unsigned)(BothPadded && C.isSaturated()), C.getScale(), + C.isSigned(), C.isSaturated(), BothPadded); + } + + /// Given a floating point type and a fixed-point semantic, return a floating + /// point type which can accommodate the fixed-point semantic. This is either + /// \p Ty, or a floating point type with a larger exponent than Ty. + Type *getAccommodatingFloatType(Type *Ty, const FixedPointSemantics &Sema) { + const fltSemantics *FloatSema = &Ty->getFltSemantics(); + while (!Sema.fitsInFloatSemantics(*FloatSema)) + FloatSema = APFixedPoint::promoteFloatSemantics(FloatSema); + return Type::getFloatingPointTy(Ty->getContext(), *FloatSema); + } + +public: + FixedPointBuilder(IRBuilderTy &Builder) : B(Builder) {} + + /// Convert an integer value representing a fixed-point number from one + /// fixed-point semantic to another fixed-point semantic. + /// \p Src - The source value + /// \p SrcSema - The fixed-point semantic of the source value + /// \p DstSema - The resulting fixed-point semantic + Value *CreateFixedToFixed(Value *Src, const FixedPointSemantics &SrcSema, + const FixedPointSemantics &DstSema) { + return Convert(Src, SrcSema, DstSema, false); + } + + /// Convert an integer value representing a fixed-point number to an integer + /// with the given bit width and signedness. + /// \p Src - The source value + /// \p SrcSema - The fixed-point semantic of the source value + /// \p DstWidth - The bit width of the result value + /// \p DstIsSigned - The signedness of the result value + Value *CreateFixedToInteger(Value *Src, const FixedPointSemantics &SrcSema, + unsigned DstWidth, bool DstIsSigned) { + return Convert( + Src, SrcSema, + FixedPointSemantics::GetIntegerSemantics(DstWidth, DstIsSigned), true); + } + + /// Convert an integer value with the given signedness to an integer value + /// representing the given fixed-point semantic. + /// \p Src - The source value + /// \p SrcIsSigned - The signedness of the source value + /// \p DstSema - The resulting fixed-point semantic + Value *CreateIntegerToFixed(Value *Src, unsigned SrcIsSigned, + const FixedPointSemantics &DstSema) { + return Convert(Src, + FixedPointSemantics::GetIntegerSemantics( + Src->getType()->getScalarSizeInBits(), SrcIsSigned), + DstSema, false); + } + + Value *CreateFixedToFloating(Value *Src, const FixedPointSemantics &SrcSema, + Type *DstTy) { + Value *Result; + Type *OpTy = getAccommodatingFloatType(DstTy, SrcSema); + // Convert the raw fixed-point value directly to floating point. If the + // value is too large to fit, it will be rounded, not truncated. + Result = SrcSema.isSigned() ? B.CreateSIToFP(Src, OpTy) + : B.CreateUIToFP(Src, OpTy); + // Rescale the integral-in-floating point by the scaling factor. This is + // lossless, except for overflow to infinity which is unlikely. + Result = B.CreateFMul(Result, + ConstantFP::get(OpTy, std::pow(2, -(int)SrcSema.getScale()))); + if (OpTy != DstTy) + Result = B.CreateFPTrunc(Result, DstTy); + return Result; + } + + Value *CreateFloatingToFixed(Value *Src, const FixedPointSemantics &DstSema) { + bool UseSigned = DstSema.isSigned() || DstSema.hasUnsignedPadding(); + Value *Result = Src; + Type *OpTy = getAccommodatingFloatType(Src->getType(), DstSema); + if (OpTy != Src->getType()) + Result = B.CreateFPExt(Result, OpTy); + // Rescale the floating point value so that its significant bits (for the + // purposes of the conversion) are in the integral range. + Result = B.CreateFMul(Result, + ConstantFP::get(OpTy, std::pow(2, DstSema.getScale()))); + + Type *ResultTy = B.getIntNTy(DstSema.getWidth()); + if (DstSema.isSaturated()) { + Intrinsic::ID IID = + UseSigned ? Intrinsic::fptosi_sat : Intrinsic::fptoui_sat; + Result = B.CreateIntrinsic(IID, {ResultTy, OpTy}, {Result}); + } else { + Result = UseSigned ? B.CreateFPToSI(Result, ResultTy) + : B.CreateFPToUI(Result, ResultTy); + } + + // When saturating unsigned-with-padding using signed operations, we may + // get negative values. Emit an extra clamp to zero. + if (DstSema.isSaturated() && DstSema.hasUnsignedPadding()) { + Constant *Zero = Constant::getNullValue(Result->getType()); + Result = + B.CreateSelect(B.CreateICmpSLT(Result, Zero), Zero, Result, "satmin"); + } + + return Result; + } + + /// Add two fixed-point values and return the result in their common semantic. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateAdd(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + Value *Result; + if (CommonSema.isSaturated()) { + Intrinsic::ID IID = UseSigned ? Intrinsic::sadd_sat : Intrinsic::uadd_sat; + Result = B.CreateBinaryIntrinsic(IID, WideLHS, WideRHS); + } else { + Result = B.CreateAdd(WideLHS, WideRHS); + } + + return CreateFixedToFixed(Result, CommonSema, + LHSSema.getCommonSemantics(RHSSema)); + } + + /// Subtract two fixed-point values and return the result in their common + /// semantic. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateSub(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + Value *Result; + if (CommonSema.isSaturated()) { + Intrinsic::ID IID = UseSigned ? Intrinsic::ssub_sat : Intrinsic::usub_sat; + Result = B.CreateBinaryIntrinsic(IID, WideLHS, WideRHS); + } else { + Result = B.CreateSub(WideLHS, WideRHS); + } + + // Subtraction can end up below 0 for padded unsigned operations, so emit + // an extra clamp in that case. + if (CommonSema.isSaturated() && CommonSema.hasUnsignedPadding()) { + Constant *Zero = Constant::getNullValue(Result->getType()); + Result = + B.CreateSelect(B.CreateICmpSLT(Result, Zero), Zero, Result, "satmin"); + } + + return CreateFixedToFixed(Result, CommonSema, + LHSSema.getCommonSemantics(RHSSema)); + } + + /// Multiply two fixed-point values and return the result in their common + /// semantic. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateMul(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + Intrinsic::ID IID; + if (CommonSema.isSaturated()) { + IID = UseSigned ? Intrinsic::smul_fix_sat : Intrinsic::umul_fix_sat; + } else { + IID = UseSigned ? Intrinsic::smul_fix : Intrinsic::umul_fix; + } + Value *Result = B.CreateIntrinsic( + IID, {WideLHS->getType()}, + {WideLHS, WideRHS, B.getInt32(CommonSema.getScale())}); + + return CreateFixedToFixed(Result, CommonSema, + LHSSema.getCommonSemantics(RHSSema)); + } + + /// Divide two fixed-point values and return the result in their common + /// semantic. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateDiv(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + bool UseSigned = CommonSema.isSigned() || CommonSema.hasUnsignedPadding(); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + Intrinsic::ID IID; + if (CommonSema.isSaturated()) { + IID = UseSigned ? Intrinsic::sdiv_fix_sat : Intrinsic::udiv_fix_sat; + } else { + IID = UseSigned ? Intrinsic::sdiv_fix : Intrinsic::udiv_fix; + } + Value *Result = B.CreateIntrinsic( + IID, {WideLHS->getType()}, + {WideLHS, WideRHS, B.getInt32(CommonSema.getScale())}); + + return CreateFixedToFixed(Result, CommonSema, + LHSSema.getCommonSemantics(RHSSema)); + } + + /// Left shift a fixed-point value by an unsigned integer value. The integer + /// value can be any bit width. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + Value *CreateShl(Value *LHS, const FixedPointSemantics &LHSSema, Value *RHS) { + bool UseSigned = LHSSema.isSigned() || LHSSema.hasUnsignedPadding(); + + RHS = B.CreateIntCast(RHS, LHS->getType(), /*IsSigned=*/false); + + Value *Result; + if (LHSSema.isSaturated()) { + Intrinsic::ID IID = UseSigned ? Intrinsic::sshl_sat : Intrinsic::ushl_sat; + Result = B.CreateBinaryIntrinsic(IID, LHS, RHS); + } else { + Result = B.CreateShl(LHS, RHS); + } + + return Result; + } + + /// Right shift a fixed-point value by an unsigned integer value. The integer + /// value can be any bit width. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + Value *CreateShr(Value *LHS, const FixedPointSemantics &LHSSema, Value *RHS) { + RHS = B.CreateIntCast(RHS, LHS->getType(), false); + + return LHSSema.isSigned() ? B.CreateAShr(LHS, RHS) : B.CreateLShr(LHS, RHS); + } + + /// Compare two fixed-point values for equality. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateEQ(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + return B.CreateICmpEQ(WideLHS, WideRHS); + } + + /// Compare two fixed-point values for inequality. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateNE(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + return B.CreateICmpNE(WideLHS, WideRHS); + } + + /// Compare two fixed-point values as LHS < RHS. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateLT(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + return CommonSema.isSigned() ? B.CreateICmpSLT(WideLHS, WideRHS) + : B.CreateICmpULT(WideLHS, WideRHS); + } + + /// Compare two fixed-point values as LHS <= RHS. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateLE(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + return CommonSema.isSigned() ? B.CreateICmpSLE(WideLHS, WideRHS) + : B.CreateICmpULE(WideLHS, WideRHS); + } + + /// Compare two fixed-point values as LHS > RHS. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateGT(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + return CommonSema.isSigned() ? B.CreateICmpSGT(WideLHS, WideRHS) + : B.CreateICmpUGT(WideLHS, WideRHS); + } + + /// Compare two fixed-point values as LHS >= RHS. + /// \p LHS - The left hand side + /// \p LHSSema - The semantic of the left hand side + /// \p RHS - The right hand side + /// \p RHSSema - The semantic of the right hand side + Value *CreateGE(Value *LHS, const FixedPointSemantics &LHSSema, + Value *RHS, const FixedPointSemantics &RHSSema) { + auto CommonSema = getCommonBinopSemantic(LHSSema, RHSSema); + + Value *WideLHS = CreateFixedToFixed(LHS, LHSSema, CommonSema); + Value *WideRHS = CreateFixedToFixed(RHS, RHSSema, CommonSema); + + return CommonSema.isSigned() ? B.CreateICmpSGE(WideLHS, WideRHS) + : B.CreateICmpUGE(WideLHS, WideRHS); + } +}; + +} // end namespace llvm + +#endif // LLVM_IR_FIXEDPOINTBUILDER_H + +#ifdef __GNUC__ +#pragma GCC diagnostic pop +#endif |