¶Optional<llvm::ValueAndVReg>
getConstantVRegValWithLookThrough(
    unsigned int VReg,
    const llvm::MachineRegisterInfo& MRI,
    bool LookThroughInstrs = true,
    bool HandleFConstants = true)

Description

If \p VReg is defined by a statically evaluable chain of instructions rooted on a G_F/CONSTANT (\p LookThroughInstrs == true) and that constant fits in int64_t, returns its value as well as the virtual register defined by this G_F/CONSTANT. When \p LookThroughInstrs == false this function behaves like getConstantVRegVal. When \p HandleFConstants == false the function bails on G_FCONSTANTs.

Declared at: llvm/include/llvm/CodeGen/GlobalISel/Utils.h:129

Parameters

unsigned int VReg

const llvm::MachineRegisterInfo& MRI

bool LookThroughInstrs = true

bool HandleFConstants = true