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  */
31 typedef 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  */
50 typedef 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  */
74 struct 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 
80 struct 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 ARM64 target VariantKinds.
100  */
101 #define LLVMDisassembler_VariantKind_ARM64_PAGE       1 /* @page */
102 #define LLVMDisassembler_VariantKind_ARM64_PAGEOFF    2 /* @pageoff */
103 #define LLVMDisassembler_VariantKind_ARM64_GOTPAGE    3 /* @gotpage */
104 #define LLVMDisassembler_VariantKind_ARM64_GOTPAGEOFF 4 /* @gotpageoff */
105 #define LLVMDisassembler_VariantKind_ARM64_TLVP       5 /* @tvlppage */
106 #define LLVMDisassembler_VariantKind_ARM64_TLVOFF     6 /* @tvlppageoff */
107 
108 /**
109  * The type for the symbol lookup function.  This may be called by the
110  * disassembler for things like adding a comment for a PC plus a constant
111  * offset load instruction to use a symbol name instead of a load address value.
112  * It is passed the block information is saved when the disassembler context is
113  * created and the ReferenceValue to look up as a symbol.  If no symbol is found
114  * for the ReferenceValue NULL is returned.  The ReferenceType of the
115  * instruction is passed indirectly as is the PC of the instruction in
116  * ReferencePC.  If the output reference can be determined its type is returned
117  * indirectly in ReferenceType along with ReferenceName if any, or that is set
118  * to NULL.
119  */
120 typedef const char *(*LLVMSymbolLookupCallback)(void *DisInfo,
121                                                 uint64_t ReferenceValue,
122                                                 uint64_t *ReferenceType,
123                                                 uint64_t ReferencePC,
124                                                 const char **ReferenceName);
125 /**
126  * The reference types on input and output.
127  */
128 /* No input reference type or no output reference type. */
129 #define LLVMDisassembler_ReferenceType_InOut_None 0
130 
131 /* The input reference is from a branch instruction. */
132 #define LLVMDisassembler_ReferenceType_In_Branch 1
133 /* The input reference is from a PC relative load instruction. */
134 #define LLVMDisassembler_ReferenceType_In_PCrel_Load 2
135 
136 /* The input reference is from an ARM64::ADRP instruction. */
137 #define LLVMDisassembler_ReferenceType_In_ARM64_ADRP 0x100000001
138 /* The input reference is from an ARM64::ADDXri instruction. */
139 #define LLVMDisassembler_ReferenceType_In_ARM64_ADDXri 0x100000002
140 /* The input reference is from an ARM64::LDRXui instruction. */
141 #define LLVMDisassembler_ReferenceType_In_ARM64_LDRXui 0x100000003
142 /* The input reference is from an ARM64::LDRXl instruction. */
143 #define LLVMDisassembler_ReferenceType_In_ARM64_LDRXl 0x100000004
144 /* The input reference is from an ARM64::ADR instruction. */
145 #define LLVMDisassembler_ReferenceType_In_ARM64_ADR 0x100000005
146 
147 /* The output reference is to as symbol stub. */
148 #define LLVMDisassembler_ReferenceType_Out_SymbolStub 1
149 /* The output reference is to a symbol address in a literal pool. */
150 #define LLVMDisassembler_ReferenceType_Out_LitPool_SymAddr 2
151 /* The output reference is to a cstring address in a literal pool. */
152 #define LLVMDisassembler_ReferenceType_Out_LitPool_CstrAddr 3
153 
154 /* The output reference is to a Objective-C CoreFoundation string. */
155 #define LLVMDisassembler_ReferenceType_Out_Objc_CFString_Ref 4
156 /* The output reference is to a Objective-C message. */
157 #define LLVMDisassembler_ReferenceType_Out_Objc_Message 5
158 /* The output reference is to a Objective-C message ref. */
159 #define LLVMDisassembler_ReferenceType_Out_Objc_Message_Ref 6
160 /* The output reference is to a Objective-C selector ref. */
161 #define LLVMDisassembler_ReferenceType_Out_Objc_Selector_Ref 7
162 /* The output reference is to a Objective-C class ref. */
163 #define LLVMDisassembler_ReferenceType_Out_Objc_Class_Ref 8
164 
165 /* The output reference is to a C++ symbol name. */
166 #define LLVMDisassembler_ReferenceType_DeMangled_Name 9
167 
168 #ifdef __cplusplus
169 extern "C" {
170 #endif /* !defined(__cplusplus) */
171 
172 /**
173  * Create a disassembler for the TripleName.  Symbolic disassembly is supported
174  * by passing a block of information in the DisInfo parameter and specifying the
175  * TagType and callback functions as described above.  These can all be passed
176  * as NULL.  If successful, this returns a disassembler context.  If not, it
177  * returns NULL. This function is equivalent to calling
178  * LLVMCreateDisasmCPUFeatures() with an empty CPU name and feature set.
179  */
180 LLVMDisasmContextRef LLVMCreateDisasm(const char *TripleName, void *DisInfo,
181                                       int TagType, LLVMOpInfoCallback GetOpInfo,
182                                       LLVMSymbolLookupCallback SymbolLookUp);
183 
184 /**
185  * Create a disassembler for the TripleName and a specific CPU.  Symbolic
186  * disassembly is supported by passing a block of information in the DisInfo
187  * parameter and specifying the TagType and callback functions as described
188  * above.  These can all be passed * as NULL.  If successful, this returns a
189  * disassembler context.  If not, it returns NULL. This function is equivalent
190  * to calling LLVMCreateDisasmCPUFeatures() with an empty feature set.
191  */
192 LLVMDisasmContextRef LLVMCreateDisasmCPU(const char *Triple, const char *CPU,
193                                          void *DisInfo, int TagType,
194                                          LLVMOpInfoCallback GetOpInfo,
195                                          LLVMSymbolLookupCallback SymbolLookUp);
196 
197 /**
198  * Create a disassembler for the TripleName, a specific CPU and specific feature
199  * string.  Symbolic disassembly is supported by passing a block of information
200  * in the DisInfo parameter and specifying the TagType and callback functions as
201  * described above.  These can all be passed * as NULL.  If successful, this
202  * returns a disassembler context.  If not, it returns NULL.
203  */
204 LLVMDisasmContextRef
205 LLVMCreateDisasmCPUFeatures(const char *Triple, const char *CPU,
206                             const char *Features, void *DisInfo, int TagType,
207                             LLVMOpInfoCallback GetOpInfo,
208                             LLVMSymbolLookupCallback SymbolLookUp);
209 
210 /**
211  * Set the disassembler's options.  Returns 1 if it can set the Options and 0
212  * otherwise.
213  */
214 int LLVMSetDisasmOptions(LLVMDisasmContextRef DC, uint64_t Options);
215 
216 /* The option to produce marked up assembly. */
217 #define LLVMDisassembler_Option_UseMarkup 1
218 /* The option to print immediates as hex. */
219 #define LLVMDisassembler_Option_PrintImmHex 2
220 /* The option use the other assembler printer variant */
221 #define LLVMDisassembler_Option_AsmPrinterVariant 4
222 /* The option to set comment on instructions */
223 #define LLVMDisassembler_Option_SetInstrComments 8
224   /* The option to print latency information alongside instructions */
225 #define LLVMDisassembler_Option_PrintLatency 16
226 
227 /**
228  * Dispose of a disassembler context.
229  */
230 void LLVMDisasmDispose(LLVMDisasmContextRef DC);
231 
232 /**
233  * Disassemble a single instruction using the disassembler context specified in
234  * the parameter DC.  The bytes of the instruction are specified in the
235  * parameter Bytes, and contains at least BytesSize number of bytes.  The
236  * instruction is at the address specified by the PC parameter.  If a valid
237  * instruction can be disassembled, its string is returned indirectly in
238  * OutString whose size is specified in the parameter OutStringSize.  This
239  * function returns the number of bytes in the instruction or zero if there was
240  * no valid instruction.
241  */
242 size_t LLVMDisasmInstruction(LLVMDisasmContextRef DC, uint8_t *Bytes,
243                              uint64_t BytesSize, uint64_t PC,
244                              char *OutString, size_t OutStringSize);
245 
246 /**
247  * @}
248  */
249 
250 #ifdef __cplusplus
251 }
252 #endif /* !defined(__cplusplus) */
253 
254 #endif /* !defined(LLVM_C_DISASSEMBLER_H) */
255