1 /*===- DataFlowCallbacks.cpp - a standalone DataFlow trace -------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 // Instrumentation callbacks for DataFlow.cpp.
9 // These functions should not be instrumented by DFSan, so we
10 // keep them in a separate file and compile it w/o DFSan.
11 //===----------------------------------------------------------------------===*/
12 #include "DataFlow.h"
13
14 #include <cassert>
15 #include <cstdio>
16 #include <cstdlib>
17
18 static __thread size_t CurrentFunc;
19 static uint32_t *GuardsBeg, *GuardsEnd;
BlockIsEntry(size_t BlockIdx)20 static inline bool BlockIsEntry(size_t BlockIdx) {
21 return __dft.PCsBeg[BlockIdx * 2 + 1] & PCFLAG_FUNC_ENTRY;
22 }
23
24 extern "C" {
25
__sanitizer_cov_trace_pc_guard_init(uint32_t * start,uint32_t * stop)26 void __sanitizer_cov_trace_pc_guard_init(uint32_t *start,
27 uint32_t *stop) {
28 assert(__dft.NumFuncs == 0 && "This tool does not support DSOs");
29 assert(start < stop && "The code is not instrumented for coverage");
30 if (start == stop || *start) return; // Initialize only once.
31 GuardsBeg = start;
32 GuardsEnd = stop;
33 }
34
__sanitizer_cov_pcs_init(const uintptr_t * pcs_beg,const uintptr_t * pcs_end)35 void __sanitizer_cov_pcs_init(const uintptr_t *pcs_beg,
36 const uintptr_t *pcs_end) {
37 if (__dft.NumGuards) return; // Initialize only once.
38 __dft.NumGuards = GuardsEnd - GuardsBeg;
39 __dft.PCsBeg = pcs_beg;
40 __dft.PCsEnd = pcs_end;
41 assert(__dft.NumGuards == (__dft.PCsEnd - __dft.PCsBeg) / 2);
42 for (size_t i = 0; i < __dft.NumGuards; i++) {
43 if (BlockIsEntry(i)) {
44 __dft.NumFuncs++;
45 GuardsBeg[i] = __dft.NumFuncs;
46 }
47 }
48 __dft.BBExecuted = (bool*)calloc(__dft.NumGuards, sizeof(bool));
49 fprintf(stderr, "INFO: %zd instrumented function(s) observed "
50 "and %zd basic blocks\n", __dft.NumFuncs, __dft.NumGuards);
51 }
52
__sanitizer_cov_trace_pc_indir(uint64_t x)53 void __sanitizer_cov_trace_pc_indir(uint64_t x){} // unused.
54
__sanitizer_cov_trace_pc_guard(uint32_t * guard)55 void __sanitizer_cov_trace_pc_guard(uint32_t *guard) {
56 size_t GuardIdx = guard - GuardsBeg;
57 // assert(GuardIdx < __dft.NumGuards);
58 __dft.BBExecuted[GuardIdx] = true;
59 if (!*guard) return; // not a function entry.
60 uint32_t FuncNum = *guard - 1; // Guards start from 1.
61 // assert(FuncNum < __dft.NumFuncs);
62 CurrentFunc = FuncNum;
63 }
64
__dfsw___sanitizer_cov_trace_switch(uint64_t Val,uint64_t * Cases,dfsan_label L1,dfsan_label UnusedL)65 void __dfsw___sanitizer_cov_trace_switch(uint64_t Val, uint64_t *Cases,
66 dfsan_label L1, dfsan_label UnusedL) {
67 assert(CurrentFunc < __dft.NumFuncs);
68 __dft.FuncLabels[CurrentFunc] |= L1;
69 }
70
71 #define HOOK(Name, Type) \
72 void Name(Type Arg1, Type Arg2, dfsan_label L1, dfsan_label L2) { \
73 __dft.FuncLabels[CurrentFunc] |= L1 | L2; \
74 }
75 //assert(CurrentFunc < __dft.NumFuncs);
76
77 HOOK(__dfsw___sanitizer_cov_trace_const_cmp1, uint8_t)
78 HOOK(__dfsw___sanitizer_cov_trace_const_cmp2, uint16_t)
79 HOOK(__dfsw___sanitizer_cov_trace_const_cmp4, uint32_t)
80 HOOK(__dfsw___sanitizer_cov_trace_const_cmp8, uint64_t)
81 HOOK(__dfsw___sanitizer_cov_trace_cmp1, uint8_t)
82 HOOK(__dfsw___sanitizer_cov_trace_cmp2, uint16_t)
83 HOOK(__dfsw___sanitizer_cov_trace_cmp4, uint32_t)
84 HOOK(__dfsw___sanitizer_cov_trace_cmp8, uint64_t)
85
86 } // extern "C"
87