llvm::SignedDivisionByConstantInfo Struct Reference

Magic data for optimising signed division by a constant. More...

#include "llvm/Support/DivisionByConstantInfo.h"

Static Public Member Functions
static SignedDivisionByConstantInfo	get (const APInt &D)
	Calculate the magic numbers required to implement a signed integer division by a constant as a sequence of multiplies, adds and shifts.

Public Attributes
APInt	Magic
	magic number
unsigned	ShiftAmount
	shift amount

Detailed Description

Magic data for optimising signed division by a constant.

Definition at line 21 of file DivisionByConstantInfo.h.

Member Function Documentation

get()

SignedDivisionByConstantInfo SignedDivisionByConstantInfo::get ( const APInt &  D )

static

Calculate the magic numbers required to implement a signed integer division by a constant as a sequence of multiplies, adds and shifts.

Requires that the divisor not be 0, 1, or -1. Taken from "Hacker's Delight", Henry S. Warren, Jr., Chapter 10.

Definition at line 21 of file DivisionByConstantInfo.cpp.

References assert(), D, llvm::APInt::getSignedMinValue(), llvm::APInt::isZero(), Magic, llvm::APInt::negate(), P, R2, ShiftAmount, llvm::APInt::udivrem(), llvm::APInt::uge(), and llvm::APInt::ult().

Referenced by llvm::TargetLowering::BuildSDIV().

Member Data Documentation

Magic

APInt llvm::SignedDivisionByConstantInfo::Magic

magic number

Definition at line 23 of file DivisionByConstantInfo.h.

Referenced by llvm::TargetLowering::BuildSDIV(), and get().

ShiftAmount

unsigned llvm::SignedDivisionByConstantInfo::ShiftAmount

shift amount

Definition at line 24 of file DivisionByConstantInfo.h.

Referenced by llvm::TargetLowering::BuildSDIV(), and get().

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The documentation for this struct was generated from the following files:

• include/llvm/Support/DivisionByConstantInfo.h
• lib/Support/DivisionByConstantInfo.cpp