LLVM 22.0.0git
InstCombineSimplifyDemanded.cpp File Reference

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Macros

#define DEBUG_TYPE   "instcombine"

Functions

static bool ShrinkDemandedConstant (Instruction *I, unsigned OpNo, const APInt &Demanded)
 Check to see if the specified operand of the specified instruction is a constant integer.
static unsigned getBitWidth (Type *Ty, const DataLayout &DL)
 Returns the bitwidth of the given scalar or pointer type.
static ConstantgetFPClassConstant (Type *Ty, FPClassTest Mask)
 For floating-point classes that resolve to a single bit pattern, return that value.

Variables

static cl::opt< boolVerifyKnownBits ("instcombine-verify-known-bits", cl::desc("Verify that computeKnownBits() and " "SimplifyDemandedBits() are consistent"), cl::Hidden, cl::init(false))
static cl::opt< unsignedSimplifyDemandedVectorEltsDepthLimit ("instcombine-simplify-vector-elts-depth", cl::desc("Depth limit when simplifying vector instructions and their operands"), cl::Hidden, cl::init(10))

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE   "instcombine"

Definition at line 25 of file InstCombineSimplifyDemanded.cpp.

Function Documentation

◆ getBitWidth()

unsigned getBitWidth ( Type * Ty,
const DataLayout & DL )
static

Returns the bitwidth of the given scalar or pointer type.

For vector types, returns the element type's bitwidth.

Definition at line 65 of file InstCombineSimplifyDemanded.cpp.

References llvm::BitWidth, and DL.

◆ getFPClassConstant()

Constant * getFPClassConstant ( Type * Ty,
FPClassTest Mask )
static

◆ ShrinkDemandedConstant()

bool ShrinkDemandedConstant ( Instruction * I,
unsigned OpNo,
const APInt & Demanded )
static

Check to see if the specified operand of the specified instruction is a constant integer.

If so, check to see if there are any bits set in the constant that are not demanded. If so, shrink the constant and return true.

Definition at line 42 of file InstCombineSimplifyDemanded.cpp.

References assert(), llvm::CallingConv::C, I, llvm::PatternMatch::m_APInt(), and llvm::PatternMatch::match().

Referenced by llvm::TargetLowering::ShrinkDemandedConstant(), llvm::TargetLowering::SimplifyDemandedBits(), and llvm::InstCombinerImpl::SimplifyDemandedUseBits().

Variable Documentation

◆ SimplifyDemandedVectorEltsDepthLimit

cl::opt< unsigned > SimplifyDemandedVectorEltsDepthLimit("instcombine-simplify-vector-elts-depth", cl::desc( "Depth limit when simplifying vector instructions and their operands"), cl::Hidden, cl::init(10)) ( "instcombine-simplify-vector-elts-depth" ,
cl::desc( "Depth limit when simplifying vector instructions and their operands") ,
cl::Hidden ,
cl::init(10)  )
static

◆ VerifyKnownBits

cl::opt< bool > VerifyKnownBits("instcombine-verify-known-bits", cl::desc("Verify that computeKnownBits() and " "SimplifyDemandedBits() are consistent"), cl::Hidden, cl::init(false)) ( "instcombine-verify-known-bits" ,
cl::desc("Verify that computeKnownBits() and " "SimplifyDemandedBits() are consistent") ,
cl::Hidden ,
cl::init(false)  )
static