1 //===-- AVRMCInstLower.cpp - Convert AVR MachineInstr to an MCInst --------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains code to lower AVR MachineInstrs to their corresponding
10 // MCInst records.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "AVRMCInstLower.h"
15 #include "AVRInstrInfo.h"
16 #include "MCTargetDesc/AVRMCAsmInfo.h"
17
18 #include "llvm/CodeGen/AsmPrinter.h"
19 #include "llvm/IR/Mangler.h"
20 #include "llvm/MC/MCInst.h"
21 #include "llvm/Support/ErrorHandling.h"
22
23 namespace llvm {
24
25 MCOperand
lowerSymbolOperand(const MachineOperand & MO,MCSymbol * Sym,const AVRSubtarget & Subtarget) const26 AVRMCInstLower::lowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym,
27 const AVRSubtarget &Subtarget) const {
28 unsigned char TF = MO.getTargetFlags();
29 const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx);
30
31 bool IsNegated = false;
32 if (TF & AVRII::MO_NEG) {
33 IsNegated = true;
34 }
35
36 if (!MO.isJTI() && MO.getOffset()) {
37 Expr = MCBinaryExpr::createAdd(
38 Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
39 }
40
41 bool IsFunction = MO.isGlobal() && isa<Function>(MO.getGlobal());
42
43 if (TF & AVRII::MO_LO) {
44 if (IsFunction) {
45 Expr = AVRMCExpr::create(Subtarget.hasEIJMPCALL() ? AVR::S_LO8_GS
46 : AVR::S_PM_LO8,
47 Expr, IsNegated, Ctx);
48 } else {
49 Expr = AVRMCExpr::create(AVR::S_LO8, Expr, IsNegated, Ctx);
50 }
51 } else if (TF & AVRII::MO_HI) {
52 if (IsFunction) {
53 Expr = AVRMCExpr::create(Subtarget.hasEIJMPCALL() ? AVR::S_HI8_GS
54 : AVR::S_PM_HI8,
55 Expr, IsNegated, Ctx);
56 } else {
57 Expr = AVRMCExpr::create(AVR::S_HI8, Expr, IsNegated, Ctx);
58 }
59 } else if (TF != 0) {
60 llvm_unreachable("Unknown target flag on symbol operand");
61 }
62
63 return MCOperand::createExpr(Expr);
64 }
65
lowerInstruction(const MachineInstr & MI,MCInst & OutMI) const66 void AVRMCInstLower::lowerInstruction(const MachineInstr &MI,
67 MCInst &OutMI) const {
68 auto &Subtarget = MI.getParent()->getParent()->getSubtarget<AVRSubtarget>();
69 OutMI.setOpcode(MI.getOpcode());
70
71 for (MachineOperand const &MO : MI.operands()) {
72 MCOperand MCOp;
73
74 switch (MO.getType()) {
75 default:
76 MI.print(errs());
77 llvm_unreachable("unknown operand type");
78 case MachineOperand::MO_Register:
79 // Ignore all implicit register operands.
80 if (MO.isImplicit())
81 continue;
82 MCOp = MCOperand::createReg(MO.getReg());
83 break;
84 case MachineOperand::MO_Immediate:
85 MCOp = MCOperand::createImm(MO.getImm());
86 break;
87 case MachineOperand::MO_GlobalAddress:
88 MCOp =
89 lowerSymbolOperand(MO, Printer.getSymbol(MO.getGlobal()), Subtarget);
90 break;
91 case MachineOperand::MO_ExternalSymbol:
92 MCOp = lowerSymbolOperand(
93 MO, Printer.GetExternalSymbolSymbol(MO.getSymbolName()), Subtarget);
94 break;
95 case MachineOperand::MO_MachineBasicBlock:
96 MCOp = MCOperand::createExpr(
97 MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
98 break;
99 case MachineOperand::MO_RegisterMask:
100 continue;
101 case MachineOperand::MO_BlockAddress:
102 MCOp = lowerSymbolOperand(
103 MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()), Subtarget);
104 break;
105 case MachineOperand::MO_JumpTableIndex:
106 MCOp = lowerSymbolOperand(MO, Printer.GetJTISymbol(MO.getIndex()),
107 Subtarget);
108 break;
109 case MachineOperand::MO_ConstantPoolIndex:
110 MCOp = lowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()),
111 Subtarget);
112 break;
113 }
114
115 OutMI.addOperand(MCOp);
116 }
117 }
118
119 } // end of namespace llvm
120