//===- X86InstrInfo.cpp - X86 Instruction Information -----------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file contains the X86 implementation of the TargetInstrInfo class.
//
#include "X86InstrInfo.h"
#include "X86.h"
-#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
-#define I(ENUM, NAME, BASEOPCODE, FLAGS, TSFLAGS, IMPDEFS, IMPUSES)
-#define IMPREGSLIST(NAME, ...) \
- static const unsigned NAME[] = { __VA_ARGS__ };
-#include "X86InstrInfo.def"
+#include "X86GenInstrInfo.inc"
-
-// X86Insts - Turn the InstrInfo.def file into a bunch of instruction
-// descriptors
-//
-static const TargetInstrDescriptor X86Insts[] = {
-#define I(ENUM, NAME, BASEOPCODE, FLAGS, TSFLAGS, IMPUSES, IMPDEFS) \
- { NAME, \
- -1, /* Always vararg */ \
- ((TSFLAGS) & X86II::Void) ? -1 : 0, /* Result is in 0 */ \
- 0, /* maxImmedConst field */\
- false, /* immedIsSignExtended */\
- 0, /* numDelaySlots */\
- 0, /* latency */\
- 0, /* schedClass */\
- FLAGS, /* Flags */\
- TSFLAGS, /* TSFlags */\
- IMPUSES, /* ImplicitUses */\
- IMPDEFS }, /* ImplicitDefs */
-#include "X86InstrInfo.def"
-};
+using namespace llvm;
X86InstrInfo::X86InstrInfo()
: TargetInstrInfo(X86Insts, sizeof(X86Insts)/sizeof(X86Insts[0]), 0) {
}
-static unsigned char BaseOpcodes[] = {
-#define I(ENUM, NAME, BASEOPCODE, FLAGS, TSFLAGS, IMPDEFS, IMPUSES) BASEOPCODE,
-#include "X86InstrInfo.def"
-};
+// createNOPinstr - returns the target's implementation of NOP, which is
+// usually a pseudo-instruction, implemented by a degenerate version of
+// another instruction, e.g. X86: `xchg ax, ax'; SparcV9: `sethi r0, r0, r0'
+//
+MachineInstr* X86InstrInfo::createNOPinstr() const {
+ return BuildMI(X86::XCHGrr16, 2).addReg(X86::AX, MachineOperand::UseAndDef)
+ .addReg(X86::AX, MachineOperand::UseAndDef);
+}
+
-// getBaseOpcodeFor - This function returns the "base" X86 opcode for the
-// specified opcode number.
+/// isNOPinstr - not having a special NOP opcode, we need to know if a given
+/// instruction is interpreted as an `official' NOP instr, i.e., there may be
+/// more than one way to `do nothing' but only one canonical way to slack off.
//
-unsigned char X86InstrInfo::getBaseOpcodeFor(unsigned Opcode) const {
- assert(Opcode < sizeof(BaseOpcodes)/sizeof(BaseOpcodes[0]) &&
- "Opcode out of range!");
- return BaseOpcodes[Opcode];
+bool X86InstrInfo::isNOPinstr(const MachineInstr &MI) const {
+ // Make sure the instruction is EXACTLY `xchg ax, ax'
+ if (MI.getOpcode() == X86::XCHGrr16) {
+ const MachineOperand &op0 = MI.getOperand(0), &op1 = MI.getOperand(1);
+ if (op0.isRegister() && op0.getReg() == X86::AX &&
+ op1.isRegister() && op1.getReg() == X86::AX) {
+ return true;
+ }
+ }
+ // FIXME: there are several NOOP instructions, we should check for them here.
+ return false;
+}
+
+bool X86InstrInfo::isMoveInstr(const MachineInstr& MI,
+ unsigned& sourceReg,
+ unsigned& destReg) const {
+ MachineOpCode oc = MI.getOpcode();
+ if (oc == X86::MOVrr8 || oc == X86::MOVrr16 || oc == X86::MOVrr32 ||
+ oc == X86::FpMOV) {
+ assert(MI.getNumOperands() == 2 &&
+ MI.getOperand(0).isRegister() &&
+ MI.getOperand(1).isRegister() &&
+ "invalid register-register move instruction");
+ sourceReg = MI.getOperand(1).getReg();
+ destReg = MI.getOperand(0).getReg();
+ return true;
+ }
+ return false;
}