1 //===- llvm/Analysis/Expressions.h - Expression Analysis Utils ---*- C++ -*--=//
3 // This file defines a package of expression analysis utilties:
5 // ClassifyExpression: Analyze an expression to determine the complexity of the
6 // expression, and which other variables it depends on.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLVM_ANALYSIS_EXPRESSIONS_H
11 #define LLVM_ANALYSIS_EXPRESSIONS_H
19 // ClassifyExpression: Analyze an expression to determine the complexity of the
20 // expression, and which other values it depends on.
22 ExprType ClassifyExpression(Value *Expr);
24 // ExprType - Represent an expression of the form CONST*VAR+CONST
25 // or simpler. The expression form that yields the least information about the
26 // expression is just the Linear form with no offset.
30 Constant, // Expr is a simple constant, Offset is value
31 Linear, // Expr is linear expr, Value is Var+Offset
32 ScaledLinear, // Expr is scaled linear exp, Value is Scale*Var+Offset
35 const ConstantInt *Offset; // Offset of expr, or null if 0
36 Value *Var; // Var referenced, if Linear or above (null if 0)
37 const ConstantInt *Scale; // Scale of var if ScaledLinear expr (null if 1)
39 inline ExprType(const ConstantInt *CPV = 0) {
40 Offset = CPV; Var = 0; Scale = 0;
43 ExprType(Value *Val); // Create a linear or constant expression
44 ExprType(const ConstantInt *scale, Value *var, const ConstantInt *offset);
46 // If this expression has an intrinsic type, return it. If it is zero, return
47 // the specified type.
49 const Type *getExprType(const Type *Default) const;