1//===-- MipsMCExpr.cpp - Mips specific MC expression classes --------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "MipsMCExpr.h"
11#include "llvm/MC/MCAsmInfo.h"
12#include "llvm/MC/MCAssembler.h"
13#include "llvm/MC/MCContext.h"
14#include "llvm/MC/MCObjectStreamer.h"
15
16using namespace llvm;
17
18#define DEBUG_TYPE "mipsmcexpr"
19
20bool MipsMCExpr::isSupportedBinaryExpr(MCSymbolRefExpr::VariantKind VK,
21                                       const MCBinaryExpr *BE) {
22  switch (VK) {
23  case MCSymbolRefExpr::VK_Mips_ABS_LO:
24  case MCSymbolRefExpr::VK_Mips_ABS_HI:
25  case MCSymbolRefExpr::VK_Mips_HIGHER:
26  case MCSymbolRefExpr::VK_Mips_HIGHEST:
27    break;
28  default:
29    return false;
30  }
31
32  // We support expressions of the form "(sym1 binop1 sym2) binop2 const",
33  // where "binop2 const" is optional.
34  if (isa<MCBinaryExpr>(BE->getLHS())) {
35    if (!isa<MCConstantExpr>(BE->getRHS()))
36      return false;
37    BE = cast<MCBinaryExpr>(BE->getLHS());
38  }
39  return (isa<MCSymbolRefExpr>(BE->getLHS())
40          && isa<MCSymbolRefExpr>(BE->getRHS()));
41}
42
43const MipsMCExpr*
44MipsMCExpr::Create(MCSymbolRefExpr::VariantKind VK, const MCExpr *Expr,
45                   MCContext &Ctx) {
46  VariantKind Kind;
47  switch (VK) {
48  case MCSymbolRefExpr::VK_Mips_ABS_LO:
49    Kind = VK_Mips_LO;
50    break;
51  case MCSymbolRefExpr::VK_Mips_ABS_HI:
52    Kind = VK_Mips_HI;
53    break;
54  case MCSymbolRefExpr::VK_Mips_HIGHER:
55    Kind = VK_Mips_HIGHER;
56    break;
57  case MCSymbolRefExpr::VK_Mips_HIGHEST:
58    Kind = VK_Mips_HIGHEST;
59    break;
60  default:
61    llvm_unreachable("Invalid kind!");
62  }
63
64  return new (Ctx) MipsMCExpr(Kind, Expr);
65}
66
67void MipsMCExpr::PrintImpl(raw_ostream &OS) const {
68  switch (Kind) {
69  default: llvm_unreachable("Invalid kind!");
70  case VK_Mips_LO: OS << "%lo"; break;
71  case VK_Mips_HI: OS << "%hi"; break;
72  case VK_Mips_HIGHER: OS << "%higher"; break;
73  case VK_Mips_HIGHEST: OS << "%highest"; break;
74  }
75
76  OS << '(';
77  Expr->print(OS);
78  OS << ')';
79}
80
81bool
82MipsMCExpr::EvaluateAsRelocatableImpl(MCValue &Res,
83                                      const MCAsmLayout *Layout) const {
84  return getSubExpr()->EvaluateAsRelocatable(Res, Layout);
85}
86
87void MipsMCExpr::visitUsedExpr(MCStreamer &Streamer) const {
88  Streamer.visitUsedExpr(*getSubExpr());
89}
90