1 //==- WebAssemblyMCTargetDesc.h - WebAssembly Target Descriptions -*- C++ -*-=//
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 /// \file
11 /// \brief This file provides WebAssembly-specific target descriptions.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_LIB_TARGET_WEBASSEMBLY_MCTARGETDESC_WEBASSEMBLYMCTARGETDESC_H
16 #define LLVM_LIB_TARGET_WEBASSEMBLY_MCTARGETDESC_WEBASSEMBLYMCTARGETDESC_H
17 
18 #include "llvm/MC/MCInstrDesc.h"
19 #include "llvm/Support/DataTypes.h"
20 
21 namespace llvm {
22 
23 class MCAsmBackend;
24 class MCCodeEmitter;
25 class MCContext;
26 class MCInstrInfo;
27 class MCObjectWriter;
28 class MCSubtargetInfo;
29 class Target;
30 class Triple;
31 class raw_pwrite_stream;
32 
33 extern Target TheWebAssemblyTarget32;
34 extern Target TheWebAssemblyTarget64;
35 
36 MCCodeEmitter *createWebAssemblyMCCodeEmitter(const MCInstrInfo &MCII);
37 
38 MCAsmBackend *createWebAssemblyAsmBackend(const Triple &TT);
39 
40 MCObjectWriter *createWebAssemblyELFObjectWriter(raw_pwrite_stream &OS,
41                                                  bool Is64Bit, uint8_t OSABI);
42 
43 namespace WebAssembly {
44 enum OperandType {
45   /// Basic block label in a branch construct.
46   OPERAND_BASIC_BLOCK = MCOI::OPERAND_FIRST_TARGET,
47   /// Floating-point immediate.
48   OPERAND_FPIMM,
49   /// p2align immediate for load and store address alignment.
50   OPERAND_P2ALIGN
51 };
52 
53 /// WebAssembly-specific directive identifiers.
54 enum Directive {
55   // FIXME: This is not the real binary encoding.
56   DotParam = UINT64_MAX - 0,   ///< .param
57   DotResult = UINT64_MAX - 1,  ///< .result
58   DotLocal = UINT64_MAX - 2,   ///< .local
59   DotEndFunc = UINT64_MAX - 3, ///< .endfunc
60 };
61 
62 } // end namespace WebAssembly
63 
64 namespace WebAssemblyII {
65 enum {
66   // For variadic instructions, this flag indicates whether an operand
67   // in the variable_ops range is an immediate value.
68   VariableOpIsImmediate = (1 << 0),
69   // For immediate values in the variable_ops range, this flag indicates
70   // whether the value represents a control-flow label.
71   VariableOpImmediateIsLabel = (1 << 1),
72 };
73 } // end namespace WebAssemblyII
74 
75 } // end namespace llvm
76 
77 // Defines symbolic names for WebAssembly registers. This defines a mapping from
78 // register name to register number.
79 //
80 #define GET_REGINFO_ENUM
81 #include "WebAssemblyGenRegisterInfo.inc"
82 
83 // Defines symbolic names for the WebAssembly instructions.
84 //
85 #define GET_INSTRINFO_ENUM
86 #include "WebAssemblyGenInstrInfo.inc"
87 
88 #define GET_SUBTARGETINFO_ENUM
89 #include "WebAssemblyGenSubtargetInfo.inc"
90 
91 namespace llvm {
92 namespace WebAssembly {
93 
94 /// Return the default p2align value for a load or store with the given opcode.
95 inline unsigned GetDefaultP2Align(unsigned Opcode) {
96   switch (Opcode) {
97   case WebAssembly::LOAD8_S_I32:
98   case WebAssembly::LOAD8_U_I32:
99   case WebAssembly::LOAD8_S_I64:
100   case WebAssembly::LOAD8_U_I64:
101   case WebAssembly::STORE8_I32:
102   case WebAssembly::STORE8_I64:
103     return 0;
104   case WebAssembly::LOAD16_S_I32:
105   case WebAssembly::LOAD16_U_I32:
106   case WebAssembly::LOAD16_S_I64:
107   case WebAssembly::LOAD16_U_I64:
108   case WebAssembly::STORE16_I32:
109   case WebAssembly::STORE16_I64:
110     return 1;
111   case WebAssembly::LOAD_I32:
112   case WebAssembly::LOAD_F32:
113   case WebAssembly::STORE_I32:
114   case WebAssembly::STORE_F32:
115   case WebAssembly::LOAD32_S_I64:
116   case WebAssembly::LOAD32_U_I64:
117   case WebAssembly::STORE32_I64:
118     return 2;
119   case WebAssembly::LOAD_I64:
120   case WebAssembly::LOAD_F64:
121   case WebAssembly::STORE_I64:
122   case WebAssembly::STORE_F64:
123     return 3;
124   default: llvm_unreachable("Only loads and stores have p2align values");
125   }
126 }
127 
128 /// The operand number of the stored value in a store instruction.
129 static const unsigned StoreValueOperandNo = 4;
130 
131 } // end namespace WebAssembly
132 } // end namespace llvm
133 
134 #endif
135