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Show First 20 Lines • Show All 156 Lines • ▼ Show 20 Lines	if (label == kInitializingLabel) {
Die();		Die();
}		}
}		}

// Resolves the union of two unequal labels. Nonequality is a precondition for		// Resolves the union of two unequal labels. Nonequality is a precondition for
// this function (the instrumentation pass inlines the equality test).		// this function (the instrumentation pass inlines the equality test).
extern "C" SANITIZER_INTERFACE_ATTRIBUTE		extern "C" SANITIZER_INTERFACE_ATTRIBUTE
dfsan_label __dfsan_union(dfsan_label l1, dfsan_label l2) {		dfsan_label __dfsan_union(dfsan_label l1, dfsan_label l2) {
		if (flags().fast16labels)
		return l1 \| l2;
DCHECK_NE(l1, l2);		DCHECK_NE(l1, l2);

if (l1 == 0)		if (l1 == 0)
return l2;		return l2;
if (l2 == 0)		if (l2 == 0)
return l1;		return l1;

if (l1 > l2)		if (l1 > l2)
▲ Show 20 Lines • Show All 280 Lines • Show Last 20 Lines

lib/dfsan/dfsan_flags.inc

Show All 23 Lines	DFSAN_FLAG(
bool, strict_data_dependencies, true,		bool, strict_data_dependencies, true,
"Whether to propagate labels only when there is an obvious data dependency"		"Whether to propagate labels only when there is an obvious data dependency"
"(e.g., when comparing strings, ignore the fact that the output of the"		"(e.g., when comparing strings, ignore the fact that the output of the"
"comparison might be data-dependent on the content of the strings). This"		"comparison might be data-dependent on the content of the strings). This"
"applies only to the custom functions defined in 'custom.c'.")		"applies only to the custom functions defined in 'custom.c'.")
DFSAN_FLAG(const char *, dump_labels_at_exit, "", "The path of the file where "		DFSAN_FLAG(const char *, dump_labels_at_exit, "", "The path of the file where "
"to dump the labels when the "		"to dump the labels when the "
"program terminates.")		"program terminates.")
		DFSAN_FLAG(bool, fast16labels, false,
		"Enables experimental mode where DFSan supports only 16 power-of-2 labels "
		"(1, 2, 4, 8, ... 32768) and the label union is computed as a bit-wise OR."
		)

				// RUN: %clang_dfsan %s -o %t && DFSAN_OPTIONS=fast16labels=1 %run %t
				//
				// Tests DFSAN_OPTIONS=fast16labels=1
				//
				#include <sanitizer/dfsan_interface.h>

				#include <assert.h>
				#include <stdio.h>

				int foo(int a, int b) {
				return a + b;
				}

				int main() {
				int a = 10;
				int b = 20;
				dfsan_set_label(8, &a, sizeof(a));
				dfsan_set_label(512, &b, sizeof(b));
				int c = foo(a, b);
				printf("A: 0x%x\n", dfsan_get_label(a));
				printf("B: 0x%x\n", dfsan_get_label(b));
				dfsan_label l = dfsan_get_label(c);
				printf("C: 0x%x\n", l);
				assert(l == 520); // OR of the other two labels.
				}