1 /*===-- disassemble.c - tool for testing libLLVM and llvm-c API -----------===*\
2 |*                                                                            *|
3 |* Part of the LLVM Project, under the Apache License v2.0 with LLVM          *|
4 |* Exceptions.                                                                *|
5 |* See https://llvm.org/LICENSE.txt for license information.                  *|
6 |* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception                    *|
7 |*                                                                            *|
8 |*===----------------------------------------------------------------------===*|
9 |*                                                                            *|
10 |* This file implements the --disassemble command in llvm-c-test.             *|
11 |* --disassemble reads lines from stdin, parses them as a triple and hex      *|
12 |*  machine code, and prints disassembly of the machine code.                 *|
13 |*                                                                            *|
14 \*===----------------------------------------------------------------------===*/
15 
16 #include "llvm-c-test.h"
17 #include "llvm-c/Disassembler.h"
18 #include "llvm-c/Target.h"
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 
pprint(int pos,unsigned char * buf,int len,const char * disasm)23 static void pprint(int pos, unsigned char *buf, int len, const char *disasm) {
24   int i;
25   printf("%04x:  ", pos);
26   for (i = 0; i < 8; i++) {
27     if (i < len) {
28       printf("%02x ", buf[i]);
29     } else {
30       printf("   ");
31     }
32   }
33 
34   printf("   %s\n", disasm);
35 }
36 
do_disassemble(const char * triple,const char * features,unsigned char * buf,int siz)37 static void do_disassemble(const char *triple, const char *features,
38                            unsigned char *buf, int siz) {
39   LLVMDisasmContextRef D = LLVMCreateDisasmCPUFeatures(triple, "", features,
40                                                        NULL, 0, NULL, NULL);
41   char outline[1024];
42   int pos;
43 
44   if (!D) {
45     printf("ERROR: Couldn't create disassembler for triple %s\n", triple);
46     return;
47   }
48 
49   pos = 0;
50   while (pos < siz) {
51     size_t l = LLVMDisasmInstruction(D, buf + pos, siz - pos, 0, outline,
52                                      sizeof(outline));
53     if (!l) {
54       pprint(pos, buf + pos, 1, "\t???");
55       pos++;
56     } else {
57       pprint(pos, buf + pos, l, outline);
58       pos += l;
59     }
60   }
61 
62   LLVMDisasmDispose(D);
63 }
64 
handle_line(char ** tokens,int ntokens)65 static void handle_line(char **tokens, int ntokens) {
66   unsigned char disbuf[128];
67   size_t disbuflen = 0;
68   const char *triple = tokens[0];
69   const char *features = tokens[1];
70   int i;
71 
72   printf("triple: %s, features: %s\n", triple, features);
73   if (!strcmp(features, "NULL"))
74     features = "";
75 
76   for (i = 2; i < ntokens; i++) {
77     disbuf[disbuflen++] = strtol(tokens[i], NULL, 16);
78     if (disbuflen >= sizeof(disbuf)) {
79       fprintf(stderr, "Warning: Too long line, truncating\n");
80       break;
81     }
82   }
83   do_disassemble(triple, features, disbuf, disbuflen);
84 }
85 
llvm_disassemble(void)86 int llvm_disassemble(void) {
87   LLVMInitializeAllTargetInfos();
88   LLVMInitializeAllTargetMCs();
89   LLVMInitializeAllDisassemblers();
90 
91   llvm_tokenize_stdin(handle_line);
92 
93   return 0;
94 }
95