Disassembler.h revision 263508 
1/*===-- llvm-c/Disassembler.h - Disassembler Public C Interface ---*- 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|* This header provides a public interface to a disassembler library.         *|
11|* LLVM provides an implementation of this interface.                         *|
12|*                                                                            *|
13\*===----------------------------------------------------------------------===*/
14
15#ifndef LLVM_C_DISASSEMBLER_H
16#define LLVM_C_DISASSEMBLER_H
17
18#include "llvm/Support/DataTypes.h"
19#include <stddef.h>
20
21/**
22 * @defgroup LLVMCDisassembler Disassembler
23 * @ingroup LLVMC
24 *
25 * @{
26 */
27
28/**
29 * An opaque reference to a disassembler context.
30 */
31typedef void *LLVMDisasmContextRef;
32
33/**
34 * The type for the operand information call back function.  This is called to
35 * get the symbolic information for an operand of an instruction.  Typically
36 * this is from the relocation information, symbol table, etc.  That block of
37 * information is saved when the disassembler context is created and passed to
38 * the call back in the DisInfo parameter.  The instruction containing operand
39 * is at the PC parameter.  For some instruction sets, there can be more than
40 * one operand with symbolic information.  To determine the symbolic operand
41 * information for each operand, the bytes for the specific operand in the
42 * instruction are specified by the Offset parameter and its byte widith is the
43 * size parameter.  For instructions sets with fixed widths and one symbolic
44 * operand per instruction, the Offset parameter will be zero and Size parameter
45 * will be the instruction width.  The information is returned in TagBuf and is
46 * Triple specific with its specific information defined by the value of
47 * TagType for that Triple.  If symbolic information is returned the function
48 * returns 1, otherwise it returns 0.
49 */
50typedef int (*LLVMOpInfoCallback)(void *DisInfo, uint64_t PC,
51                                  uint64_t Offset, uint64_t Size,
52                                  int TagType, void *TagBuf);
53
54/**
55 * The initial support in LLVM MC for the most general form of a relocatable
56 * expression is "AddSymbol - SubtractSymbol + Offset".  For some Darwin targets
57 * this full form is encoded in the relocation information so that AddSymbol and
58 * SubtractSymbol can be link edited independent of each other.  Many other
59 * platforms only allow a relocatable expression of the form AddSymbol + Offset
60 * to be encoded.
61 *
62 * The LLVMOpInfoCallback() for the TagType value of 1 uses the struct
63 * LLVMOpInfo1.  The value of the relocatable expression for the operand,
64 * including any PC adjustment, is passed in to the call back in the Value
65 * field.  The symbolic information about the operand is returned using all
66 * the fields of the structure with the Offset of the relocatable expression
67 * returned in the Value field.  It is possible that some symbols in the
68 * relocatable expression were assembly temporary symbols, for example
69 * "Ldata - LpicBase + constant", and only the Values of the symbols without
70 * symbol names are present in the relocation information.  The VariantKind
71 * type is one of the Target specific #defines below and is used to print
72 * operands like "_foo@GOT", ":lower16:_foo", etc.
73 */
74struct LLVMOpInfoSymbol1 {
75  uint64_t Present;  /* 1 if this symbol is present */
76  const char *Name;  /* symbol name if not NULL */
77  uint64_t Value;    /* symbol value if name is NULL */
78};
79
80struct LLVMOpInfo1 {
81  struct LLVMOpInfoSymbol1 AddSymbol;
82  struct LLVMOpInfoSymbol1 SubtractSymbol;
83  uint64_t Value;
84  uint64_t VariantKind;
85};
86
87/**
88 * The operand VariantKinds for symbolic disassembly.
89 */
90#define LLVMDisassembler_VariantKind_None 0 /* all targets */
91
92/**
93 * The ARM target VariantKinds.
94 */
95#define LLVMDisassembler_VariantKind_ARM_HI16 1 /* :upper16: */
96#define LLVMDisassembler_VariantKind_ARM_LO16 2 /* :lower16: */
97
98/**
99 * The type for the symbol lookup function.  This may be called by the
100 * disassembler for things like adding a comment for a PC plus a constant
101 * offset load instruction to use a symbol name instead of a load address value.
102 * It is passed the block information is saved when the disassembler context is
103 * created and the ReferenceValue to look up as a symbol.  If no symbol is found
104 * for the ReferenceValue NULL is returned.  The ReferenceType of the
105 * instruction is passed indirectly as is the PC of the instruction in
106 * ReferencePC.  If the output reference can be determined its type is returned
107 * indirectly in ReferenceType along with ReferenceName if any, or that is set
108 * to NULL.
109 */
110typedef const char *(*LLVMSymbolLookupCallback)(void *DisInfo,
111                                                uint64_t ReferenceValue,
112                                                uint64_t *ReferenceType,
113                                                uint64_t ReferencePC,
114                                                const char **ReferenceName);
115/**
116 * The reference types on input and output.
117 */
118/* No input reference type or no output reference type. */
119#define LLVMDisassembler_ReferenceType_InOut_None 0
120
121/* The input reference is from a branch instruction. */
122#define LLVMDisassembler_ReferenceType_In_Branch 1
123/* The input reference is from a PC relative load instruction. */
124#define LLVMDisassembler_ReferenceType_In_PCrel_Load 2
125
126/* The output reference is to as symbol stub. */
127#define LLVMDisassembler_ReferenceType_Out_SymbolStub 1
128/* The output reference is to a symbol address in a literal pool. */
129#define LLVMDisassembler_ReferenceType_Out_LitPool_SymAddr 2
130/* The output reference is to a cstring address in a literal pool. */
131#define LLVMDisassembler_ReferenceType_Out_LitPool_CstrAddr 3
132
133/* The output reference is to a Objective-C CoreFoundation string. */
134#define LLVMDisassembler_ReferenceType_Out_Objc_CFString_Ref 4
135/* The output reference is to a Objective-C message. */
136#define LLVMDisassembler_ReferenceType_Out_Objc_Message 5
137/* The output reference is to a Objective-C message ref. */
138#define LLVMDisassembler_ReferenceType_Out_Objc_Message_Ref 6
139/* The output reference is to a Objective-C selector ref. */
140#define LLVMDisassembler_ReferenceType_Out_Objc_Selector_Ref 7
141/* The output reference is to a Objective-C class ref. */
142#define LLVMDisassembler_ReferenceType_Out_Objc_Class_Ref 8
143
144#ifdef __cplusplus
145extern "C" {
146#endif /* !defined(__cplusplus) */
147
148/**
149 * Create a disassembler for the TripleName.  Symbolic disassembly is supported
150 * by passing a block of information in the DisInfo parameter and specifying the
151 * TagType and callback functions as described above.  These can all be passed
152 * as NULL.  If successful, this returns a disassembler context.  If not, it
153 * returns NULL. This function is equivalent to calling LLVMCreateDisasmCPU()
154 * with an empty CPU name.
155 */
156LLVMDisasmContextRef LLVMCreateDisasm(const char *TripleName, void *DisInfo,
157                                      int TagType, LLVMOpInfoCallback GetOpInfo,
158                                      LLVMSymbolLookupCallback SymbolLookUp);
159
160/**
161 * Create a disassembler for the TripleName and a specific CPU.  Symbolic
162 * disassembly is supported by passing a block of information in the DisInfo
163 * parameter and specifying the TagType and callback functions as described
164 * above.  These can all be passed * as NULL.  If successful, this returns a
165 * disassembler context.  If not, it returns NULL.
166 */
167LLVMDisasmContextRef LLVMCreateDisasmCPU(const char *Triple, const char *CPU,
168                                         void *DisInfo, int TagType,
169                                         LLVMOpInfoCallback GetOpInfo,
170                                         LLVMSymbolLookupCallback SymbolLookUp);
171
172/**
173 * Set the disassembler's options.  Returns 1 if it can set the Options and 0
174 * otherwise.
175 */
176int LLVMSetDisasmOptions(LLVMDisasmContextRef DC, uint64_t Options);
177
178/* The option to produce marked up assembly. */
179#define LLVMDisassembler_Option_UseMarkup 1
180/* The option to print immediates as hex. */
181#define LLVMDisassembler_Option_PrintImmHex 2
182/* The option use the other assembler printer variant */
183#define LLVMDisassembler_Option_AsmPrinterVariant 4
184/* The option to set comment on instructions */
185#define LLVMDisassembler_Option_SetInstrComments 8
186  /* The option to print latency information alongside instructions */
187#define LLVMDisassembler_Option_PrintLatency 16
188
189/**
190 * Dispose of a disassembler context.
191 */
192void LLVMDisasmDispose(LLVMDisasmContextRef DC);
193
194/**
195 * Disassemble a single instruction using the disassembler context specified in
196 * the parameter DC.  The bytes of the instruction are specified in the
197 * parameter Bytes, and contains at least BytesSize number of bytes.  The
198 * instruction is at the address specified by the PC parameter.  If a valid
199 * instruction can be disassembled, its string is returned indirectly in
200 * OutString whose size is specified in the parameter OutStringSize.  This
201 * function returns the number of bytes in the instruction or zero if there was
202 * no valid instruction.
203 */
204size_t LLVMDisasmInstruction(LLVMDisasmContextRef DC, uint8_t *Bytes,
205                             uint64_t BytesSize, uint64_t PC,
206                             char *OutString, size_t OutStringSize);
207
208/**
209 * @}
210 */
211
212#ifdef __cplusplus
213}
214#endif /* !defined(__cplusplus) */
215
216#endif /* !defined(LLVM_C_DISASSEMBLER_H) */
217