1 //===-- TargetInstrInfo.cpp - Target Instruction Information --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the TargetInstrInfo class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Target/TargetInstrInfo.h"
15 #include "llvm/CodeGen/MachineInstr.h"
16 #include "llvm/Constant.h"
17 #include "llvm/DerivedTypes.h"
21 // External object describing the machine instructions Initialized only when
22 // the TargetMachine class is created and reset when that class is destroyed.
24 // FIXME: UGLY SPARCV9 HACK!
25 const TargetInstrDescriptor* TargetInstrDescriptors = 0;
28 TargetInstrInfo::TargetInstrInfo(const TargetInstrDescriptor* Desc,
30 : desc(Desc), NumOpcodes(numOpcodes) {
31 // FIXME: TargetInstrDescriptors should not be global
32 assert(TargetInstrDescriptors == NULL && desc != NULL
33 && "TargetMachine data structure corrupt; maybe you tried to create another TargetMachine? (only one may exist in a program)");
34 TargetInstrDescriptors = desc; // initialize global variable
37 TargetInstrInfo::~TargetInstrInfo() {
38 TargetInstrDescriptors = NULL; // reset global variable
41 // FIXME: SPARCV9 SPECIFIC!
42 bool TargetInstrInfo::constantFitsInImmedField(MachineOpCode opCode,
43 int64_t intValue) const {
44 // First, check if opCode has an immed field.
46 uint64_t maxImmedValue = maxImmedConstant(opCode, isSignExtended);
47 if (maxImmedValue != 0)
49 // NEED TO HANDLE UNSIGNED VALUES SINCE THEY MAY BECOME MUCH
50 // SMALLER AFTER CASTING TO SIGN-EXTENDED int, short, or char.
51 // See CreateUIntSetInstruction in SparcInstrInfo.cpp.
53 // Now check if the constant fits
54 if (intValue <= (int64_t) maxImmedValue &&
55 intValue >= -((int64_t) maxImmedValue+1))
62 // commuteInstruction - The default implementation of this method just exchanges
64 MachineInstr *TargetInstrInfo::commuteInstruction(MachineInstr *MI) const {
65 assert(MI->getOperand(1).isRegister() && MI->getOperand(2).isRegister() &&
66 "This only knows how to commute register operands so far");
67 unsigned Reg1 = MI->getOperand(1).getReg();
68 unsigned Reg2 = MI->getOperand(1).getReg();
69 MI->SetMachineOperandReg(2, Reg1);
70 MI->SetMachineOperandReg(1, Reg2);