1 //===-- nsan.cc -----------------------------------------------------------===//
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
12 //  - The public nsan interface (include/sanitizer/nsan_interface.h).
13 //  - The private nsan interface (./nsan.h).
14 //  - The internal instrumentation interface. These are function emitted by the
25 //          on the runtime configuration. The middle part indicates the type of
27 //          shadow, and depends on the instrumentation configuration.
31 //===----------------------------------------------------------------------===//
57 // FIXME: We could provide fixed-size versions that would nicely
67 // FIXME: We could provide fixed-size versions that would nicely
111   const char *Name() { return Green(); }  in Name()
124     snprintf(result.Buffer, sizeof(result.Buffer) - 1, "%.20f", value);  in dec()
129     snprintf(result.Buffer, sizeof(result.Buffer) - 1, "%.20a", value);  in hex()
139     snprintf(result.Buffer, sizeof(result.Buffer) - 1, "%.20Lf", value);  in dec()
144     snprintf(result.Buffer, sizeof(result.Buffer) - 1, "%.20La", value);  in hex()
161 template <typename FT> inline FT ftAbs(FT v) { return v >= FT{0} ? v : -v; }  in ftAbs()
189     nsan_stats->Print();  in __nsan_print_accumulated_stats()
200 // storing ourselves because it avoids having to rely on the calling convention
254           // Warn only if the value is non-zero. Zero is special because  in getShadowPtrForLoad()
259             nsan_stats->AddUnknownLoadTrackingEvent(pc, bp);  in getShadowPtrForLoad()
263           nsan_stats->AddInvalidLoadTrackingEvent(pc, bp);  in getShadowPtrForLoad()
313     const u8 T = *(shadow_type - pos + i);  in checkValueConsistency()
336   int LastPos = -1;  in __nsan_dump_shadow_mem()
338   for (size_t R = 0; R < (size_bytes + bytes_per_line - 1) / bytes_per_line;  in __nsan_dump_shadow_mem()
348         LastPos = pos == 0 ? 0 : -1;  in __nsan_dump_shadow_mem()
357         if (LastPos == sizeof(float) - 1) {  in __nsan_dump_shadow_mem()
359               ReadShadow(shadow + kShadowScale * (Offset + 1 - sizeof(float)),  in __nsan_dump_shadow_mem()
366         if (LastPos == sizeof(double) - 1) {  in __nsan_dump_shadow_mem()
368               shadow + kShadowScale * (Offset + 1 - sizeof(double)),  in __nsan_dump_shadow_mem()
375         if (LastPos == sizeof(long double) - 1) {  in __nsan_dump_shadow_mem()
377               shadow + kShadowScale * (Offset + 1 - sizeof(long double)),  in __nsan_dump_shadow_mem()
411 enum ContinuationType { // Keep in sync with instrumentation pass.
430   // https://randomascii.wordpress.com/2012/02/25/comparing-floating-point-numbers-2012-edition/  in checkFT()
433   const InternalFT abs_err = ftAbs(check_value - check_shadow);  in checkFT()
437     // We are re-computing `largest` here because this is a cold branch, and we  in checkFT()
441     nsan_stats->AddCheck(CheckType, pc, bp, abs_err / largest);  in checkFT()
445   // (value and shadow are inf or -inf), we pass the test.  in checkFT()
468       snprintf(RelErrBuf, sizeof(RelErrBuf) - 1, "%.20Lf%% (2^%.0Lf epsilons)",  in checkFT()
478           shadow_ulp_diff / (u64{1} << (FTInfo<InternalFT>::kMantissaBits -  in checkFT()
480       snprintf(ulp_err_buf, sizeof(ulp_err_buf) - 1,  in checkFT()
510       Printf(" in user-initiated check");  in checkFT()
518            "%-12s precision  (native): dec: %s  hex: %s\n"  in checkFT()
519            "%-12s precision  (shadow): dec: %s  hex: %s\n"  in checkFT()
520            "shadow truncated to %-12s: dec: %s  hex: %s\n"  in checkFT()
535     nsan_stats->AddWarning(CheckType, pc, bp, abs_err / largest);  in checkFT()
539     if (common_flags()->abort_on_error)  in checkFT()
631     nsan_stats->AddWarning(CheckTypeT::kFcmp, pc, bp, 0.0);  in fCmpFailFT()
644   Printf("WARNING: NumericalStabilitySanitizer: floating-point comparison "  in fCmpFailFT()
645          "results depend on precision\n");  in fCmpFailFT()
647   Printf("%-12s precision dec (native): %s %s %s (%s)\n"  in fCmpFailFT()
648          "%-12s precision dec (shadow): %s %s %s (%s)\n"  in fCmpFailFT()
649          "%-12s precision hex (native): %s %s %s (%s)\n"  in fCmpFailFT()
650          "%-12s precision hex (shadow): %s %s %s (%s)\n"  in fCmpFailFT()
708   // the instrumentation will have placed the shadow value on the shadow stack.  in checkFTFromShadowStack()
719          "__nsan_check_float called from non-instrumented function");  in __nsan_check_float()
726          "__nsan_check_double called from non-instrumented function");  in __nsan_check_double()
733          "__nsan_check_longdouble called from non-instrumented function");  in __nsan_check_longdouble()
740   // the instrumentation will have placed the shadow value on the shadow stack.  in dumpFTFromShadowStack()
754          "__nsan_dump_float called from non-instrumented function");  in __nsan_dump_float()
760          "__nsan_dump_double called from non-instrumented function");  in __nsan_dump_double()
767          "__nsan_dump_longdouble called from non-instrumented function");  in __nsan_dump_longdouble()
798   if (!MmapFixedNoReserve(TypesAddr(), UnusedAddr() - TypesAddr()))  in __nsan_init()