1 //===-- MSP430InstPrinter.cpp - Convert MSP430 MCInst to assembly syntax --===//
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 class prints an MSP430 MCInst to a .s file.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "MSP430InstPrinter.h"
14 #include "MSP430.h"
15 #include "llvm/MC/MCAsmInfo.h"
16 #include "llvm/MC/MCExpr.h"
17 #include "llvm/MC/MCInst.h"
18 #include "llvm/MC/MCInstrInfo.h"
19 #include "llvm/Support/ErrorHandling.h"
20 #include "llvm/Support/FormattedStream.h"
21 using namespace llvm;
22 
23 #define DEBUG_TYPE "asm-printer"
24 
25 // Include the auto-generated portion of the assembly writer.
26 #define PRINT_ALIAS_INSTR
27 #include "MSP430GenAsmWriter.inc"
28 
29 void MSP430InstPrinter::printInst(const MCInst *MI, uint64_t Address,
30                                   StringRef Annot, const MCSubtargetInfo &STI,
31                                   raw_ostream &O) {
32   if (!printAliasInstr(MI, O))
33     printInstruction(MI, Address, O);
34   printAnnotation(O, Annot);
35 }
36 
37 void MSP430InstPrinter::printPCRelImmOperand(const MCInst *MI, unsigned OpNo,
38                                              raw_ostream &O) {
39   const MCOperand &Op = MI->getOperand(OpNo);
40   if (Op.isImm()) {
41     int64_t Imm = Op.getImm() * 2 + 2;
42     O << "$";
43     if (Imm >= 0)
44       O << '+';
45     O << Imm;
46   } else {
47     assert(Op.isExpr() && "unknown pcrel immediate operand");
48     Op.getExpr()->print(O, &MAI);
49   }
50 }
51 
52 void MSP430InstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
53                                      raw_ostream &O, const char *Modifier) {
54   assert((Modifier == nullptr || Modifier[0] == 0) && "No modifiers supported");
55   const MCOperand &Op = MI->getOperand(OpNo);
56   if (Op.isReg()) {
57     O << getRegisterName(Op.getReg());
58   } else if (Op.isImm()) {
59     O << '#' << Op.getImm();
60   } else {
61     assert(Op.isExpr() && "unknown operand kind in printOperand");
62     O << '#';
63     Op.getExpr()->print(O, &MAI);
64   }
65 }
66 
67 void MSP430InstPrinter::printSrcMemOperand(const MCInst *MI, unsigned OpNo,
68                                            raw_ostream &O,
69                                            const char *Modifier) {
70   const MCOperand &Base = MI->getOperand(OpNo);
71   const MCOperand &Disp = MI->getOperand(OpNo+1);
72 
73   // Print displacement first
74 
75   // If the global address expression is a part of displacement field with a
76   // register base, we should not emit any prefix symbol here, e.g.
77   //   mov.w &foo, r1
78   // vs
79   //   mov.w glb(r1), r2
80   // Otherwise (!) msp430-as will silently miscompile the output :(
81   if (Base.getReg() == MSP430::SR)
82     O << '&';
83 
84   if (Disp.isExpr())
85     Disp.getExpr()->print(O, &MAI);
86   else {
87     assert(Disp.isImm() && "Expected immediate in displacement field");
88     O << Disp.getImm();
89   }
90 
91   // Print register base field
92   if ((Base.getReg() != MSP430::SR) &&
93       (Base.getReg() != MSP430::PC))
94     O << '(' << getRegisterName(Base.getReg()) << ')';
95 }
96 
97 void MSP430InstPrinter::printIndRegOperand(const MCInst *MI, unsigned OpNo,
98                                            raw_ostream &O) {
99   const MCOperand &Base = MI->getOperand(OpNo);
100   O << "@" << getRegisterName(Base.getReg());
101 }
102 
103 void MSP430InstPrinter::printPostIndRegOperand(const MCInst *MI, unsigned OpNo,
104                                                raw_ostream &O) {
105   const MCOperand &Base = MI->getOperand(OpNo);
106   O << "@" << getRegisterName(Base.getReg()) << "+";
107 }
108 
109 void MSP430InstPrinter::printCCOperand(const MCInst *MI, unsigned OpNo,
110                                        raw_ostream &O) {
111   unsigned CC = MI->getOperand(OpNo).getImm();
112 
113   switch (CC) {
114   default:
115    llvm_unreachable("Unsupported CC code");
116   case MSP430CC::COND_E:
117    O << "eq";
118    break;
119   case MSP430CC::COND_NE:
120    O << "ne";
121    break;
122   case MSP430CC::COND_HS:
123    O << "hs";
124    break;
125   case MSP430CC::COND_LO:
126    O << "lo";
127    break;
128   case MSP430CC::COND_GE:
129    O << "ge";
130    break;
131   case MSP430CC::COND_L:
132    O << 'l';
133    break;
134   case MSP430CC::COND_N:
135    O << 'n';
136    break;
137   }
138 }
139