1//===-- BPFInstPrinter.cpp - Convert BPF MCInst to asm 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 BPF MCInst to a .s file.
10//
11//===----------------------------------------------------------------------===//
12
13#include "MCTargetDesc/BPFInstPrinter.h"
14#include "BPF.h"
15#include "llvm/MC/MCAsmInfo.h"
16#include "llvm/MC/MCExpr.h"
17#include "llvm/MC/MCInst.h"
18#include "llvm/MC/MCSymbol.h"
19#include "llvm/Support/Casting.h"
20#include "llvm/Support/ErrorHandling.h"
21using namespace llvm;
22
23#define DEBUG_TYPE "asm-printer"
24
25// Include the auto-generated portion of the assembly writer.
26#include "BPFGenAsmWriter.inc"
27
28void BPFInstPrinter::printInst(const MCInst *MI, uint64_t Address,
29 StringRef Annot, const MCSubtargetInfo &STI,
30 raw_ostream &O) {
31 printInstruction(MI, Address, O);
32 printAnnotation(OS&: O, Annot);
33}
34
35void BPFInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
36 raw_ostream &O) {
37 const MCOperand &Op = MI->getOperand(i: OpNo);
38 if (Op.isReg()) {
39 O << getRegisterName(Reg: Op.getReg());
40 } else if (Op.isImm()) {
41 O << formatImm(Value: (int32_t)Op.getImm());
42 } else {
43 assert(Op.isExpr() && "Expected an expression");
44 MAI.printExpr(O, *Op.getExpr());
45 }
46}
47
48void BPFInstPrinter::printMemOperand(const MCInst *MI, int OpNo,
49 raw_ostream &O) {
50 const MCOperand &RegOp = MI->getOperand(i: OpNo);
51 const MCOperand &OffsetOp = MI->getOperand(i: OpNo + 1);
52
53 // register
54 assert(RegOp.isReg() && "Register operand not a register");
55 O << getRegisterName(Reg: RegOp.getReg());
56
57 // offset
58 if (OffsetOp.isImm()) {
59 auto Imm = OffsetOp.getImm();
60 if (Imm >= 0)
61 O << " + " << formatImm(Value: Imm);
62 else
63 O << " - " << formatImm(Value: -Imm);
64 } else {
65 assert(0 && "Expected an immediate");
66 }
67}
68
69void BPFInstPrinter::printImm64Operand(const MCInst *MI, unsigned OpNo,
70 raw_ostream &O) {
71 const MCOperand &Op = MI->getOperand(i: OpNo);
72 if (Op.isImm())
73 O << formatImm(Value: Op.getImm());
74 else if (Op.isExpr())
75 MAI.printExpr(O, *Op.getExpr());
76 else
77 O << Op;
78}
79
80void BPFInstPrinter::printBrTargetOperand(const MCInst *MI, unsigned OpNo,
81 raw_ostream &O) {
82 const MCOperand &Op = MI->getOperand(i: OpNo);
83 if (Op.isImm()) {
84 if (MI->getOpcode() == BPF::JMPL) {
85 int32_t Imm = Op.getImm();
86 O << ((Imm >= 0) ? "+" : "") << formatImm(Value: Imm);
87 } else {
88 int16_t Imm = Op.getImm();
89 O << ((Imm >= 0) ? "+" : "") << formatImm(Value: Imm);
90 }
91 } else if (Op.isExpr()) {
92 MAI.printExpr(O, *Op.getExpr());
93 } else {
94 O << Op;
95 }
96}
97