llvm-project

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// REQUIRES: target={{x86_64-.*}}
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// RUN: %clang_dfsan -gmlt -mllvm -dfsan-track-origins=1 %s -o %t && \
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// RUN:     %run %t >%t.out 2>&1
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// RUN: FileCheck %s < %t.out
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#include <sanitizer/dfsan_interface.h>
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int main(int argc, char *argv[]) {
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  uint64_t a = 10;
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  dfsan_set_label(1, &a, sizeof(a));
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  // Manually compute origin address for &a.
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  // See x86 MEM_TO_ORIGIN macro for logic to replicate here.
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  // Alignment is also needed after to MEM_TO_ORIGIN.
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  uint64_t origin_addr =
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      (((uint64_t)&a ^ 0x500000000000ULL) + 0x100000000000ULL) & ~0x3ULL;
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  // Take the address we computed, and store 0 in it to mess it up.
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  asm("mov %0, %%rax": :"r"(origin_addr));
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  asm("movq $0, (%rax)");
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  dfsan_print_origin_trace(&a, "invalid");
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}
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// CHECK: Taint value 0x1 (at {{.*}}) origin tracking (invalid)
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// CHECK: Taint value 0x1 (at {{.*}}) has invalid origin tracking. This can be a DFSan bug.
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